Spinal instrumentation in infants, children, and adolescents: a review

JNSPG 75th Anniversary Invited Review Article

Free access

OBJECTIVE

The evolution of pediatric spinal instrumentation has progressed in the last 70 years since the popularization of the Harrington rod showing the feasibility of placing spinal instrumentation into the pediatric spine. Although lacking in pediatric-specific spinal instrumentation, when possible, adult instrumentation techniques and tools have been adapted for the pediatric spine. A new generation of pediatric neurosurgeons with interest in complex spine disorder has pushed the field forward, while keeping the special nuances of the growing immature spine in mind. The authors sought to review their own experience with various types of spinal instrumentation in the pediatric spine and document the state of the art for pediatric spine surgery.

METHODS

The authors retrospectively reviewed patients in their practice who underwent complex spine surgery. Patient demographics, operative data, and perioperative complications were recorded. At the same time, the authors surveyed the literature for spinal instrumentation techniques that have been utilized in the pediatric spine. The authors chronicle the past and present of pediatric spinal instrumentation, and speculate about its future.

RESULTS

The medical records of the first 361 patients who underwent 384 procedures involving spinal instrumentation from July 1, 2007, to May 31, 2018, were analyzed. The mean age at surgery was 12 years and 6 months (range 3 months to 21 years and 4 months). The types of spinal instrumentation utilized included occipital screws (94 cases); C1 lateral mass screws (115 cases); C2 pars/translaminar screws (143 cases); subaxial cervical lateral mass screws (95 cases); thoracic and lumbar spine traditional-trajectory and cortical-trajectory pedicle screws (234 cases); thoracic and lumbar sublaminar, subtransverse, and subcostal polyester bands (65 cases); S1 pedicle screws (103 cases); and S2 alar-iliac/iliac screws (56 cases). Complications related to spinal instrumentation included hardware-related skin breakdown (1.8%), infection (1.8%), proximal junctional kyphosis (1.0%), pseudarthroses (1.0%), screw malpositioning (0.5%), CSF leak (0.5%), hardware failure (0.5%), graft migration (0.3%), nerve root injury (0.3%), and vertebral artery injury (0.3%).

CONCLUSIONS

Pediatric neurosurgeons with an interest in complex spine disorders in children should develop a comprehensive armamentarium of safe techniques for placing rigid and nonrigid spinal instrumentation even in the smallest of children, with low complication rates. The authors’ review provides some benchmarks and outcomes for comparison, and furnishes a historical perspective of the past and future of pediatric spine surgery.

ABBREVIATIONS BMP = bone morphogenetic protein; PEEK = polyetheretherketone.

Abstract

OBJECTIVE

The evolution of pediatric spinal instrumentation has progressed in the last 70 years since the popularization of the Harrington rod showing the feasibility of placing spinal instrumentation into the pediatric spine. Although lacking in pediatric-specific spinal instrumentation, when possible, adult instrumentation techniques and tools have been adapted for the pediatric spine. A new generation of pediatric neurosurgeons with interest in complex spine disorder has pushed the field forward, while keeping the special nuances of the growing immature spine in mind. The authors sought to review their own experience with various types of spinal instrumentation in the pediatric spine and document the state of the art for pediatric spine surgery.

METHODS

The authors retrospectively reviewed patients in their practice who underwent complex spine surgery. Patient demographics, operative data, and perioperative complications were recorded. At the same time, the authors surveyed the literature for spinal instrumentation techniques that have been utilized in the pediatric spine. The authors chronicle the past and present of pediatric spinal instrumentation, and speculate about its future.

RESULTS

The medical records of the first 361 patients who underwent 384 procedures involving spinal instrumentation from July 1, 2007, to May 31, 2018, were analyzed. The mean age at surgery was 12 years and 6 months (range 3 months to 21 years and 4 months). The types of spinal instrumentation utilized included occipital screws (94 cases); C1 lateral mass screws (115 cases); C2 pars/translaminar screws (143 cases); subaxial cervical lateral mass screws (95 cases); thoracic and lumbar spine traditional-trajectory and cortical-trajectory pedicle screws (234 cases); thoracic and lumbar sublaminar, subtransverse, and subcostal polyester bands (65 cases); S1 pedicle screws (103 cases); and S2 alar-iliac/iliac screws (56 cases). Complications related to spinal instrumentation included hardware-related skin breakdown (1.8%), infection (1.8%), proximal junctional kyphosis (1.0%), pseudarthroses (1.0%), screw malpositioning (0.5%), CSF leak (0.5%), hardware failure (0.5%), graft migration (0.3%), nerve root injury (0.3%), and vertebral artery injury (0.3%).

CONCLUSIONS

Pediatric neurosurgeons with an interest in complex spine disorders in children should develop a comprehensive armamentarium of safe techniques for placing rigid and nonrigid spinal instrumentation even in the smallest of children, with low complication rates. The authors’ review provides some benchmarks and outcomes for comparison, and furnishes a historical perspective of the past and future of pediatric spine surgery.

The pediatric spine may be affected by various pathologies, which can be categorized as congenital, developmental, and acquired. These etiologies of pediatric spine disease represent an important distinction from those in adults. The inherent properties of the pediatric spine, such as diminutive anatomy, absence of pediatric-specific instrumentation, and inability to extrapolate adult techniques to a child, make the insertion of pediatric instrumentation challenging. A singular problem in the pediatric age group is the restrictive, unwanted effects of spinal instrumentation on the skeletally immature spine. Fusing the skeletally immature spine may lead to far more serious issues beyond growth retardation. These issues may include restrictive lung disease, pulmonary hypertension, right heart failure, and death.

This review of our experience and series of pediatric patients describes seldom-used anterior and more often used posterior approaches for the placement of spinal instrumentation in the pediatric spine. It surveys the history of spinal instrumentation in children, beginning with Paul Harrington and his revolutionary treatment for scoliosis in children with polio. Various biomaterials and other surgical adjuncts, such as intraoperative navigation, are considered. Lastly, we briefly survey future directions for pediatric spinal instrumentation.

Methods

Our experience with the first 384 spinal fusions with instrumentation in children (age ≤ 21 years) was reviewed from July 1, 2007, to May 31, 2018. Up until July 31, 2016, surgeries were performed at Texas Children’s Hospital in Houston, Texas (299 cases); thereafter, procedures were performed at Riley Hospital for Children in Indianapolis, Indiana (85 cases).

Patient Demographics

There were 361 patients who underwent 384 operative procedures involving spinal instrumentation. Boys accounted for 48.2% of the population. The mean age at the time of surgery was 12 years and 6 months (range 3 months to 21 years and 4 months). The indications for spinal fusion can be divided into degenerative, congenital, trauma, and tumor (Table 1).

TABLE 1.

Patient demographics and operative data

Value
Patient demographics
 Patients, n361
 Spinal fusions, n384
 Mean age (range), yrs12.5 (0.3–21.3)
 Male, n (%)185 (48)
Indications for spinal fusion
 Degenerative, n (%)59 (15)
 Congenital, n (%)215 (56)
 Trauma, n (%)76 (20)
 Tumor, n (%)34 (9)
Location of spinal fusion
 Craniocervical junction (Oc–C2), n142
 Subaxial cervical spine (C3–7), n99
 Thoracic spine (T1–9), n129
 Thoracolumbar junction (T10–L2), n142
 Lumbar spine (L3–5), n165
 Sacrum, n105
 Pelvis, n57
Approach to the spine
 Posterior, n (%)360 (93)
 Anterior, n (%)10 (3)
 Combined, n (%)14 (4)
Spinal fixation devices & techniques
 Occipital screws, n94
 C1 lateral mass screws, n115
 C2 pars/translaminar screws, n143
 Subaxial cervical lateral mass screws, n95
 Thoracic/lumbar pedicle screws, n234
 Sublaminar polyester bands, n65
 S1 pedicle screws, n103
 S2 alar-iliac/iliac screws, n56

Oc = occiput.

Operative Data

Among surgeries performed, spinal instrumentation was placed at the craniocervical junction (occiput–C2; 142 cases), subaxial cervical spine (C3–7; 99 cases), thoracic spine (T1–9; 129 cases), thoracolumbar junction (T10–L2; 142 cases), lumbar spine (L3–5; 165 cases), sacrum (105 cases), and pelvis (57 cases) (Table 1). Of the 384 cases, 360 were performed from a posterior-only approach, 14 cases were performed from combined anterior and posterior approaches, and 10 cases were performed from an anterior-only approach. It is important to note that anterior-only approaches were limited to cervical spine cases.

The types of spinal fixation devices and techniques used included occipital screws (94 cases); C1 lateral mass screws (115 cases); C2 pars/translaminar screws (143 cases); subaxial cervical lateral mass screws (95 cases); thoracic and lumbar spine traditional-trajectory and cortical-trajectory pedicle screws (234 cases); thoracic and lumbar sublaminar, subtransverse, and subcostal polyester bands (65 cases); S1 pedicle screws (103 cases); and S2 alar-iliac/iliac screws (56 cases) (Table 1). Based on our experience with spinal instrumentation in children, we describe our personal biases in selecting and placing anchor points in the spine of young children. Stepwise instruction and surgical indications for placement of spinal instrumentation in a child are included in our prior publications.34

Description of Techniques

Posterior Spinal Instrumentation

Craniocervical Junction (occiput–C2)

Occipital Fixation. The zone of failure for occipitocervical instrumentation is usually at the point of fixation to the occiput. A child’s head is disproportionately large compared with that of adults, especially in the occipital region. Moreover, the necessity to keep the head and neck in a neutral position rather than flexed, or in a military tuck position, produces an acute angle between the slope of the occiput and the line of the cervical spine.106,112,123 These geometric constraints require extreme bends in the rods and subsequent notching of the rods that span occipitocervical fusions. Additionally, the average skull thickness in the occipital region in children is 3.8 mm compared with 6.7 mm in adults.4 Because of poor screw purchase, thin bone stock, and rod notching, children may be more prone to instrumentation failure at its attachment to the skull.46,47,110

Bicortical screw placement between the superior and inferior nuchal lines seems to be superior to unicortical placement in biomechanical studies.56,160 On the other hand, bicortical screw placement carries higher risk than unicortical screw placement. With bicortical screw placement, there are risks of durotomy, CSF leakage, dural venous sinus injury, and intracranial hemorrhage.63,127 CSF leakage and venous bleeding from an injured sinus may be stopped by working quickly to place the screw or plugging the hole in the skull with bone wax. Our occipital fixation technique is illustrated in Fig. 1.

Fig. 1.
Fig. 1.

Occipital fixation. Tapping (A) and placement (B) of occipital screws. The stop-drill technique, which consists of triangulating toward the midline, performed slowly until penetration of the inner table of the skull, is routinely used to prevent dural and sinus laceration. Right- and left-sided screw trajectories are staggered to prevent screw paths from intersecting. Screws are typically placed between the inferior and superior nuchal lines. Screws may be placed in a unicortical fashion near the superior nuchal line to prevent penetration of the transverse sinus. Image created by Katherine Relyea, MS, CMI, and printed with permission from Baylor College of Medicine; first appeared in Chern JJ, et al: Instrumentation and stabilization of the pediatric spine: technical nuances and age-specific considerations, in Quinones-Hinojosa A (ed): Schmidek & Sweet: Operative Neurosurgical Techniques: Indications, Methods, and Results, ed 6. Philadelphia: Elsevier Saunders, 2012, Vol 1, pp 759–767.

C1 Lateral Mass Screws and C1–2 Transarticular Screws. The biomechanically sound Magerl technique69 for C1–2 transarticular screw placement traverses 4 cortical surfaces and the C1–2 joint (Fig. 2). However, it is technically demanding and places the vertebral arteries at risk. The rates of vertebral artery injury (2%–8%) are likely underreported in the literature.39,45,52,93 The use of this technique has been infrequently described in the pediatric spine.52,94,109,145

Fig. 2.
Fig. 2.

C1–2 transarticular screw technique. Note the screw proximity to the vertebral arteries, making this a very challenging stabilization technique in children. Image created by Katherine Relyea, MS, CMI, and printed with permission from Baylor College of Medicine; first appeared in Chern JJ, et al: Instrumentation and stabilization of the pediatric spine: technical nuances and age-specific considerations, in Quinones-Hinojosa A (ed): Schmidek & Sweet: Operative Neurosurgical Techniques: Indications, Methods, and Results, ed 6. Philadelphia: Elsevier Saunders, 2012, Vol 1, pp 759–767.

Because of the prohibitive technical and anatomical requirements for the Magerl technique, C1–2 transarticular screws have given way to C1–2 screw-plate or screw-rod constructs as described by Goel and Laheri,53,55 and Harms and Melcher,57 respectively. The Goel/Harms technique for C1–2 posterior instrumented fusion may be more applicable even in the smallest of children or those with anatomical variants (Fig. 3).

Fig. 3.
Fig. 3.

C1 lateral mass crew technique. The entry point of the C1 lateral mass screw is deep at the confluence of the C1 lamina and C1 lateral mass to avoid the vertebral artery in the more superficial sulcus arteriosus. The medial surface of the C1 lateral mass should be palpated as an important landmark. The entry point should be 2–3 mm from the medial aspect of the C1 lateral mass. The lateral aspect of the lateral mass should be avoided, as this is where the vertebral artery resides. Bicortical screw purchase is desired to increase pullout strength. To help with exposure of the bony landmarks for C1 lateral mass screw placement, we recommend sectioning the C2 nerve root. Judicious (and continuous) bipolar coagulation of the venous plexus surrounding the C2 nerve root should be performed. Stepwise division of the C2 nerve root proximal to the dorsal root ganglion. There is no reason to rush this portion of the procedure if acceptable blood loss is a goal of surgery. Image created by Katherine Relyea, MS, CMI, and printed with permission from Baylor College of Medicine; first appeared in Chern JJ, et al: Instrumentation and stabilization of the pediatric spine: technical nuances and age-specific considerations, in Quinones-Hinojosa A (ed): Schmidek & Sweet: Operative Neurosurgical Techniques: Indications, Methods, and Results, ed 6. Philadelphia: Elsevier Saunders, 2012, Vol 1, pp 759–767.

C1 lateral mass screw placement may itself carry the risks of vertebral artery injury, but our experience and that of others53,57,68,139 show that it can be performed safely and be an efficacious part of an atlantoaxial or occipitocervical construct in children.

C2 Pars/Pedicle and Translaminar Screws. C2 pars/pedicle screw placement carries a smaller risk of vertebral artery injury than C1–2 transarticular screw placement.65 However, the risk to the vertebral arteries and spinal cord is still definable (Fig. 4).119

Fig. 4.
Fig. 4.

C2 pars/pedicle screw technique. Note the proximity of the spinal canal and vertebral artery in comparison with the translaminar screw in Fig. 5. Image created by Katherine Relyea, MS, CMI, and printed with permission from Baylor College of Medicine; first appeared in Chern JJ, et al: Instrumentation and stabilization of the pediatric spine: technical nuances and age-specific considerations, in Quinones-Hinojosa A (ed): Schmidek & Sweet: Operative Neurosurgical Techniques: Indications, Methods, and Results, ed 6. Philadelphia: Elsevier Saunders, 2012, Vol 1, pp 759–767.

Wright160,161 described the translaminar screw technique (Fig. 5). Translaminar screw technique allows for safe, rigid fixation of C2 by circumventing the risk of vertebral artery injury. The literature demonstrates that this technique of crossing and noncrossing laminar screws is a safe and effective method of C2 fixation in children.32,87,136 Although a recent meta-analysis of cadaver studies brought concern with the lateral bending stability in C1 lateral mass–C2 translaminar screws, the difference was not statistically significant.42 Based on reports in the literature of the small series of children and slightly larger patient series of adults in which C2 translaminar screws are used, the follow-up and fusion rate are quite satisfactory.138

Fig. 5.
Fig. 5.

Translaminar screw technique. C2 translaminar screw fixation is a safe technique for rigid fixation and avoids the vertebral arteries. A potential drawback to this technique is breach of the nonvisualized ventral laminar wall leading to dural laceration, CSF leak, or spinal cord injury. Wright’s method for placing laminar screws can be modified with a small exit window in the dorsal cortex of the lamina at the laminofacet line. This exit window allows the surgeon to visualize the tip of the screw to ensure that it has not penetrated the ventral laminar cortex. Careful study of the preoperative CT scan can indicate screw length and width. Image created by Katherine Relyea, MS, CMI, and printed with permission from Baylor College of Medicine; first appeared in Chern JJ, et al: Instrumentation and stabilization of the pediatric spine: technical nuances and age-specific considerations, in Quinones-Hinojosa A (ed): Schmidek & Sweet: Operative Neurosurgical Techniques: Indications, Methods, and Results, ed 6. Philadelphia: Elsevier Saunders, 2012, Vol 1, pp 759–767.

Subaxial Cervical Spine (C3–7)

Lateral Mass Screws. Lateral mass screw fixation of the cervical spine has been shown to be effective in adult patients.36,124,134 There are 2 popular techniques for placing lateral mass screws. These are the Roy-Camille and Magerl techniques, both of which have been extrapolated to pediatric patients. The youngest patient reported who underwent successful lateral mass screw placement was 8.2 years old.9 This corresponds with the age in which the pediatric spine is expected to transform into its adult configuration.12

Placing lateral mass screws in even younger children is feasible. However, surgery can be challenging because of proximity to the vertebral arteries, small bone volume in the lateral mass to safely accommodate a screw of sufficient width and length (3.5 × 14 mm),134 and violation of the facet joint, which predisposes to untoward adjacent-level changes.9,12,25 Often, the spine surgeon is allowed only one opportunity to accurately place a screw, as the small size of the lateral mass does not allow for multiple attempts. Furthermore, a shorter screw may need to be placed (3.5 × 10 mm), compromising the strength of the construct. Our technique for placing subaxial lateral mass screws is illustrated in Fig. 6.

Fig. 6.
Fig. 6.

C3–7 lateral mass screw technique. The entire lateral mass of the subaxial cervical spine should be exposed at each level. On the dorsal square face of the lateral mass, an entry point 1 mm medial and 1 mm caudal from the midpoint (dot) should be selected. The drill and screw trajectory should be directed “up and out” toward the deep superior and ventral corner of the lateral mass box (about 20° lateral and 20° rostral) to avoid vertebral artery and nerve root injury, respectively. Image created by Katherine Relyea, MS, CMI, and printed with permission from Baylor College of Medicine; first appeared in Chern JJ, et al: Instrumentation and stabilization of the pediatric spine: technical nuances and age-specific considerations, in Quinones-Hinojosa A (ed): Schmidek & Sweet: Operative Neurosurgical Techniques: Indications, Methods, and Results, ed 6. Philadelphia: Elsevier Saunders, 2012, Vol 1, pp 759–767.

Sublaminar Wires. Sublaminar wires are considered “old school” but solid alternatives when lateral mass screws are not feasible.35,50,103,144,148 They are still frequently used in combination with contoured rods and/or lateral mass screws. It has been demonstrated that the wires confer immediate stability and help achieve solid fusion. In a biomechanical study13 and systematic review155 comparing rigid constructs (screw-rod) and nonrigid constructs (screw-wire/wires only), screw-rod constructs outperform screw-wire/wire-only constructs in terms of instrumentation failure and fusion rates. Furthermore, our series of pediatric spine cases indicate that instrumentation of the cervical spine may carry a safer and more efficacious profile than a wire construct.66 The sublaminar wire method, nevertheless, remains a salvage method to obtain internal support for fusion.76,97,116

Pedicle Screws. Unlike in the thoracic and lumbar spine, subaxial cervical pedicle screws are not widely utilized because of the high risk to adjacent neurovascular structures involved in cannulating the cervical pedicles.21 Abumi et al.,1,2 alone advocate for cervical pedicle screws, reported excellent clinical outcomes for use in the middle to lower cervical spine.

Translaminar Screws. Subaxial cervical translaminar screw placement is an option as a fixation point (Fig. 5). Theoretically, translaminar screws can be placed under direct vision, avoid important neurovascular structures, and attain a screw length much longer than a lateral mass screw. In reality, however, the laminar thickness of the subaxial cervical spine in a child can rarely accommodate a translaminar screw.33

Thoracic and Lumbar Spine

Wires, Hooks, and Pedicle Screws. Posterior thoracolumbar instrumentation has been traditionally divided into rigid and nonrigid constructs. The earliest arthrodesis constructs incorporated the spinous processes or other dorsal bony structures with structural autograft.28 Although simple wiring techniques are no longer used today, Luque wiring, which employs sublaminar wires as anchor points, is still used occasionally. The Luque instrumentation system was a step toward more rigid segmental spinal instrumentation, avoiding mandatory postoperative external orthoses.93 Wiring techniques are considered nonrigid because they allow “pistoning” of the spine in a craniocaudal direction.

The first hook-based system was the Harrington rod, which was introduced in the 1960s.137 These constructs were much more rigid than previous wiring techniques, leading to improved fusion rates that avoided the need for postoperative bracing.93 The disadvantage of these constructs, as with pedicle screw fixation, is the effect of fusion on adjacent segments. In contrast to the 3D fixation of pedicle screw constructs, hooks anchor to the posterior elements alone and do not have the same ability to correct severe scoliosis curves.85

Spinal instrumentation in the thoracic and lumbar spine has primarily been applied to the surgical reduction and fixation of spinal deformities. After the introduction of pedicle screws22 and advent of Harrington instrumentation,59 spinal internal pedicle screw fixation gained popularity in the operative treatment of traumatic and nontraumatic spine disorders.20,78,125,126 Pedicle screw fixation offer 3-column control of the spinal column with powerful correction in the axial, sagittal, and coronal planes (Fig. 7). When compared with nonrigid methods, such as hook-and-wire constructs, pedicle screw constructs have higher fusion rates, lower implant failures, and obviate the need for postoperative bracing.14,90,91,143

Fig. 7.
Fig. 7.

Thoracic and lumbar pedicle screw technique. Pedicle screw placement may start at the confluence of the pars interarticularis and transverse process. Rostral-caudal and mediolateral angulation of the pedicles should be studied prior to surgery at each vertebral level to help guide screw trajectory. There may be a role for intraoperative image guidance in the placement of pedicle screws. Image created by Katherine Relyea, MS, CMI, and printed with permission from Baylor College of Medicine; first appeared in Chern JJ, et al: Instrumentation and stabilization of the pediatric spine: technical nuances and age-specific considerations, in Quinones-Hinojosa A (ed): Schmidek & Sweet: Operative Neurosurgical Techniques: Indications, Methods, and Results, ed 6. Philadelphia: Elsevier Saunders, 2012, Vol 1, pp 759–767.

Polyester Bands. Polyester bands with a locking mechanism to the rod are a relatively new innovation. They serve as an alternative to traditional anchors, such as wire, hooks, and screws. Polyester is a biologically inert material with favorable mechanical properties, such as high tensile strength, high resistance to stretch, wet or dry, and resistance to degradation.133 It represents an excellent candidate material for use in the spine. As an example, polyester has been incorporated in spinal constructs in Europe for more than 20 years (K. Mazda, personal communication, October 17, 2007).

The gentleness and flexibility of polyester seem to make it ideal for implantation in the pediatric spine. It is particularly useful when anatomy precludes safe placement of hooks or screws despite the availability of image guidance. Like other anchors to the spine, these polyester bands along with their rod-locking mechanism may be used to attain segmental control, reduction, and fusion (Fig. 8). Like other forms of sublaminar spinal instrumentation, such as sublaminar wire or laminar hooks, sublaminar polyester bands have a higher risk of spinal cord injury than pedicle screws.15,29,51,62,72,92,141 The intracanalicular space is violated with each pass of the sublaminar polyester band, whereas the intention of pedicle screws is to stay intraosseous and outside the spinal canal. The learning curve for placing sublaminar polyester bands is comparatively shorter than for placing pedicle screws; nonetheless, meticulous technique is necessary to reduce the risk of spinal cord injury, especially in the thoracic and thoracolumbar spine.

Fig. 8.
Fig. 8.

Sublaminar wire/band technique. The ligamentum flavum is resected in the interlaminar spaces above and below the lamina of interest. We are careful not to resect too much of the lamina itself. A gentle curve for the malleable semirigid tip of the wire or polyester band is created. The tip is passed gently underneath the lamina from caudal to rostral. A hemostat or nerve hook is used to snare the tip of the wire or polyester band. Through use of a push-pull technique to avoid a loop of wire or band compressing the thecal sac and spinal cord, the wire or band is progressively passed underneath the lamina until the semirigid tip has fully traversed the lamina. Once all sublaminar wires or bands have been passed, each wire or band is secured to the rod. Sequential tensioning may then be applied to produce a translation of the spine toward the rod. Image created by Katherine Relyea, MS, CMI, and printed with permission from Baylor College of Medicine; first appeared in Chern JJ, et al: Instrumentation and stabilization of the pediatric spine: technical nuances and age-specific considerations, in Quinones-Hinojosa A (ed): Schmidek & Sweet: Operative Neurosurgical Techniques: Indications, Methods, and Results, ed 6. Philadelphia: Elsevier Saunders, 2012, Vol 1, pp 759–767.

Complications may also occur with over-tensioning of the polyester bands, causing them to fracture through osteoporotic or partially cartilaginous bone, which was encountered in our early experience with these bands. Aggressive decortication of the lamina and subsequent decrease in laminar strength may also predispose it to fracture.11 Promising results have been demonstrated with hybrid spinal constructs incorporating sublaminar polyester bands; however, long-term evaluations are still needed.38,142

Complications and Complication-Avoidance Strategies

There were no deaths attributable to spinal instrumentation placement in our series of children. However, other complications included hardware-related skin breakdown (1.8%), infection (1.8%), proximal junctional kyphosis (1.0%), pseudarthrosis (1.0%), screw malpositioning (0.5%), cerebrospinal fluid leak (0.5%), hardware failure (0.5%), graft migration (0.3%), nerve root injury (0.3%), and vertebral artery injury (0.3%). Our avoidance strategies for each of these complications are detailed in Table 2.

TABLE 2.

Complications and avoidance strategies

ComplicationsAvoidance Strategies
Hardware-related skin breakdown• Counter-sinking lower-profile spinal instrumentation to ensure no local prominence

• Periop consultation & collaboration w/ plastic surgery to discuss need for soft-tissue flaps &/or expanders

• Consultation to optimize nutritional status prior to surgery
Infection• Preop nutrition consultation to control preop hyperglycemia & weight loss prior to surgery; remembering that an obese patient can still be malnourished

• Following a standardized complex spine infection prevention protocol, including preop skin antisepsis w/ chlorhexidine surgical scrubs; use of adapted antimicrobial prophylaxis protocols w/ preincision cefazolin; intraop pulse irrigation w/ antibiotic solution & intraop topical vancomycin powder
Proximal junctional kyphosis/pseudarthrosis• Decreasing rigidity at the top of long-segment constructs by placement of hooks rather than pedicle screws to provide a transition to the noninstrumented spine

• Bending kyphosis into the rods at the rostral end of the spinal construct

• Using rods that are less stiff, such as titanium alloy or cobalt-chrome, rather than stainless steel
Screw malpositioning• Use of intraop computerized image-guided screw insertion techniques

• Intraop CT to check postinsertion screw placement

• Careful attention to trajectory & anatomical landmarks during screw placement, even when using adjuncts like image guidance
CSF leak• Awareness of anatomical anomalies or bony defects on preop imaging

• Meticulous attention to development of surgical planes between the dura & overlying bone or soft tissue during decompression procedures

• Use of eggshell technique during use of the high-speed air-powered drill

• Employing the surgical assistant to protect the dura while working close to it
Hardware failure• Careful attention to spinal alignment during deformity correction—avoidance of over- or under-correction

• Achieving a well-balanced spine will place less stress on the rods

• Considering “outriggers” or a 4-rod construct that spans 3-column osteotomy sites or irreducible unbalanced spinal deformities
Nerve root/vertebral artery injury• Careful study of preoperative imaging, such as CTA &/or MRI, particularly in cases of congenital anomalies of the spine at the craniocervical junction

Discussion

History of Spinal Instrumentation in Children

The history of spinal instrumentation in children begins with the treatment of scoliosis by luminaries in spine surgery, including Dr. Russell A. Hibbs, Dr. Fred H. Albee, and Dr. H. P. H. Galloway.37

The greatest breakthrough for the operative treatment of scoliosis came with the advent of the Harrington rod. Dr. Harrington started practice in Houston, Texas, in 1945 at Jefferson Hospital. During this time, he took a special interest in children with poliomyelitis and the high incidence of neuromuscular scoliosis in this patient population.37,58 Dr. Harrington quickly realized at the time that the therapies used to treat idiopathic scoliosis—physical therapy, bracing, casting, and early surgical techniques—were not appropriate for poliomyelitis patients. The Harrington rod was born out of his curiosity and compassion for patients; it was the first iteration of an implantable spinal instrumentation system.37

After the Harrington rod system, many other notable systems, such as the Luque instrumentation system in 197793 and the Cotrel-Dubousset system in 1978, were created utilizing the contemporary spine surgery knowledge and techniques for deformity correction. This trend in development of spinal instrumentation represented a slow march toward 3D control and 3-column fixation of the spinal column, the standard for spinal instrumentation systems today.10,120,121,151

Anterior Spinal Instrumentation

Anterior approaches to the spinal column for the placement of instrumentation are infrequent compared with posterior approaches. Anterior spinal instrumentation is most commonly confined to the cervical spine. Case series on anterior spine instrumentation have recently been reported.48

Advantages of Anterior Instrumentation

There are several important advantages to anterior approaches over posterior approaches. The patient does not need to be turned prone for positioning on the operating room table, which is important when the spinal column is unstable. Anterior spinal instrumentation may allow for less extensive fusion (i.e., motion segments spared), may require less soft-tissue dissection to expose the spine, may be associated with decreased blood loss, and may have higher fusion rates and lower infection rates.16,44,95,147,149,154 In the growing spine, addition of anterior instrumentation to a previous posterior fusion construct (circumferential fusion) may help prevent the occurrence of “crankshaft” deformity.41,82,140

Disadvantages of Anterior Instrumentation

The most significant disadvantage of anterior spinal instrumentation is that it is rarely a stand-alone construct. A second procedure may be required to place supplemental posterior spinal instrumentation. Contemporary posterior or posterolateral approaches to the spine (e.g., costotransversectomy and lateral extracavitary) may allow simultaneous exposure of the anterior, middle, and posterior columns of the spine.118 In these approaches, anterior and posterior spinal instrumentation may be inserted through a single approach.

Biomaterials

Autograft, including iliac crest, tibia/fibula, and rib, remains the gold standard in pediatric spine surgery. However, the materials may also be primarily cartilaginous in young children, thereby limiting its use as structural autograft. Titanium and polyetheretherketone (PEEK) cages79 have been used as vehicles to hold graft material while providing immediate load-bearing properties.6,30,31,86 Due to the favorable modulus of elasticity of PEEK in comparison with bone, it is preferred over titanium cages.159 Titanium cage use is reserved for older children and adolescents with higher density bone;6 otherwise, titanium cages are prone to settle and telescope.

The off-label use of bone morphogenetic protein (BMP) has increased in both the adult and pediatric patient populations since its approval by the FDA in 2002.67 Allograft, in combination with BMP, may provide high fusion rates that rival that of the autograft gold standard. In younger children where the quantity of autograft is limited, BMP offers a promising alternative. Other purported advantages of BMP include decreased operative time, lower blood loss, and elimination of donor site morbidity. The safety and efficacy of BMP has been documented in adult and pediatric case reports and case series.64,130–132 Reported complications of BMP include seroma formation, soft-tissue swelling, delayed wound healing, and heterotopic bone formation. The long-term effects of BMP, such as oncogenesis, are unknown. Therefore, full informed consent from patients and their parents for the cautious use of BMP should be obtained.

Intraoperative Spinal Navigation

The use of intraoperative spinal navigation for screw insertion has been shown to improve accuracy and decrease unexpected returns to the operating room for screw revision.7,73,96,102,104,115,150 The use of computerized image guidance in the pediatric spine seems even more opportune as there is a smaller margin for error in placing spinal instrumentation. Most of the pediatric spine literature82,83,117 has confirmed that intraoperative spinal navigation results in a low rate of misplaced screws and related reoperations.

A potential criticism of intraoperative spinal navigation is the radiation exposure during intraoperative CT scanning, especially in the pediatric population.75,122 There are numerous studies that correlate early exposure to radiation in pediatric populations to long-term increased cancer risk.3,24,74 More long-term studies are necessary to assess long-term cancer risk in pediatric patients undergoing spinal instrumentation.

Long-Term Consequences of Fusion in a Growing Spine

A major difference between the pediatric spine and adult spine is the potential for continued growth from childhood to adolescence.71 This growth must be factored into any decision of performing a long-segment fusion in a child. Adverse iatrogenic effects from spinal fusion include limitation of range of motion, stunting future growth, development of secondary deformity (e.g., crankshaft deformity), and adjacent-level disease.60,156–158

Because there are no epiphyseal growth plates between the occiput and C2, it is not unexpected that several studies have shown minimal effect of vertical growth restriction across an occipitocervical fusion.5,8,12,52,74,98,113,146,152 A dedicated study analyzing spinal alignment and growth in children after subaxial cervical fusion demonstrated that there are continued dynamic changes across the fused segments.54 The authors showed 79%, 83%, and 100% of expected growth across 4-level, 3-level, and 2-level fusions, respectively. Overall, 62% of patients with 24 months of follow-up showed growth across the fusion construct. Crankshaft deformity occurs when posterior fusion is achieved yet unrestricted growth continues in the anterior column of a young child.43,61,84 The posterior fusion mass then acts as a tether and center of rotation causing progressive angulation and lordosis. As mentioned previously, completion of a circumferential fusion (i.e., addition of an anterior fusion) may arrest crankshaft deformity.41,81 However, this possible solution for crankshaft deformity is controversial, debated, and being studied.26,129

Long-segment thoracic fusion should be avoided in children younger than 8 years, as alveolar and lung development occurs until the age of 8 years.40 Fusion of the spine while lung maturity is occurring can result in restrictive lung disease and subsequent pulmonary hypertension. Pulmonary hypertension can lead to right heart failure and iatrogenic death—a complication from inappropriate fusion across the thoracic spine and rib cage.

Adjacent-level disease is defined as premature degeneration of supra- or subjacent levels to fusion. The fused segment is spared biomechanical force, but this excess force is distributed to the next mobile segments above and below. The rate of development of adjacent-level disease during the first 10 years after anterior cervical discectomy and fusion is estimated to be 2.9% per year in adult studies. In the adult lumbar spine, the rate of adjacent-level disease is estimated to be 3.6% per year.49 To our knowledge, the rate of adjacent-segment degeneration in children has not been assessed. Logically, children should carry a much greater risk of adjacent-segment degeneration given a much longer life expectancy. Further studies are needed to elucidate this risk.

Fusionless Spine Surgery

The future of spine surgery in children may lie in the continued refinement of fusionless techniques to allow growth and preserve motion. Growing rod constructs, such as traditional growing rods, the Shilla technique, vertical expandable prosthetic titanium rib (VEPTR, DePuy Synthes), and magnetic expansion control (MAGEC, NuVasive) rods, have been used to address early-onset scoliosis.27,70,99 However, these techniques are plagued with complications and unexpected outcomes, including wound breakdown, infection, premature auto-fusion, and device failure.17,80,89,153

Vertebral body growth modulation is a new and exciting area in the field of fusionless deformity surgery. Progression of skeletal deformity during growth is thought to be governed by the Hueter-Volkmann law.100 This law states that growth depends on the amount of compression on the growth plate. Increased compression retards growth, while decreased compression accelerates growth. If this principle is applied to the growing child with scoliosis, then the concave portion of the scoliotic spine will have increased loading on the vertebral body growth plate—retarding growth—and the convex portion of the curve will have decreased loading—increasing growth—leading to an overall vicious cycle of curve progression. Various skeletal fixation devices have been successfully used in animal models to correct induced scoliosis curves.23,101,105,107,108

Based on the above principles, vertebral body stapling and vertebral body tethering were developed. The results with each technique appear to be promising. Vertebral body stapling involves placing unilateral disc-sparing staples on the convex side of a scoliotic curve to increase compression on the growth plate and reduce overall growth.18,19,128

There is mounting evidence that intricate underlying genetic abnormalities contribute to the 3D structural deformities found in scoliosis. Prior studies have identified candidate genes associated with adolescent idiopathic scoliosis, such as GPR126,77 BNC2,111 PAX1,135 LBX1as1,163 POC5,114 and AKAP2.88 More recently, MapK7 was shown to be associated with severe spinal deformity and a defective osteogenesis phenotype in idiopathic scoliosis.162 Understanding the molecular underpinnings that generate spinal deformities may allow for early targeted therapy based on a child’s underlying genetic profile. The development and refinement of new fusionless surgical techniques may allow for early treatment of pediatric patients with high risk of deformity progression without the long-term consequences of current fusion constructs.

Conclusions

Pediatric neurosurgeons with an interest in complex spine disorders in children should develop a comprehensive armamentarium of safe techniques for placing rigid and nonrigid spinal instrumentation even in the smallest of children, with low complication rates. The present review provides some benchmarks and outcomes for comparison, and furnishes a historical perspective of the past and future of pediatric spine surgery.

Acknowledgments

In memory of Dr. Sanjiv Bhatia.

Disclosures

The authors report no conflict of interest concerning the materials or methods used in this study or the findings specified in this paper.

Author Contributions

Conception and design: Jea, Mendenhall, Mobasser. Acquisition of data: Jea, Mendenhall, Mobasser. Analysis and interpretation of data: Jea, Mendenhall, Mobasser. Drafting the article: Jea, Mendenhall, Mobasser. Critically revising the article: Jea, Mendenhall. Reviewed submitted version of manuscript: Jea, Mendenhall, Mobasser. Approved the final version of the manuscript on behalf of all authors: Jea. Administrative/technical/material support: all authors. Study supervision: Jea, Mendenhall, Mobasser. Illustrator: Relyea.

References

  • 1

    Abumi KItoh HTaneichi HKaneda K: Transpedicular screw fixation for traumatic lesions of the middle and lower cervical spine: description of the techniques and preliminary report. J Spinal Disord 7:19281994

  • 2

    Abumi KKaneda K: Pedicle screw fixation for nontraumatic lesions of the cervical spine. Spine (Phila Pa 1976) 22:185318631997

  • 3

    Acharya SSarafoglou KLaQuaglia MLindsley SGerald WWollner N: Thyroid neoplasms after therapeutic radiation for malignancies during childhood or adolescence. Cancer 97:239724032003

  • 4

    Adeloye AKattan KRSilverman FN: Thickness of the normal skull in the American blacks and whites. Am J Phys Anthropol 43:23301975

  • 5

    Ahmed RTraynelis VCMenezes AH: Fusions at the craniovertebral junction. Childs Nerv Syst 24:120912242008

  • 6

    Akamaru TKawahara NTsuchiya HKobayashi TMurakami HTomita K: Healing of autologous bone in a titanium mesh cage used in anterior column reconstruction after total spondylectomy. Spine (Phila Pa 1976) 27:E329E3332002

  • 7

    Amiot LPLang KPutzier MZippel HLabelle H: Comparative results between conventional and computer-assisted pedicle screw installation in the thoracic, lumbar, and sacral spine. Spine (Phila Pa 1976) 25:6066142000

  • 8

    Anderson RCKan PGluf WMBrockmeyer DL: Long-term maintenance of cervical alignment after occipitocervical and atlantoaxial screw fixation in young children. J Neurosurg 105 (1 Suppl):55612006

  • 9

    Anderson RCRagel BTMocco JBohman LEBrockmeyer DL: Selection of a rigid internal fixation construct for stabilization at the craniovertebral junction in pediatric patients. J Neurosurg 107 (1 Suppl):36422007

  • 10

    Asher MLai SMBurton DManna BCooper A: Safety and efficacy of Isola instrumentation and arthrodesis for adolescent idiopathic scoliosis: two- to 12-year follow-up. Spine (Phila Pa 1976) 29:201320232004

  • 11

    Aydingoz OBilsel NBotanlioglu HBozdag ESunbuloglu EKesmezacar H: Effect of decortication on laminar strength during sublaminar wiring: an experimental study. J Spinal Disord Tech 17:4985042004

  • 12

    Bailey DK: The normal cervical spine in infants and children. Radiology 59:7127191952

  • 13

    Bambakidis NCFeiz-Erfan IHorn EMGonzalez LFBaek SYüksel KZ: Biomechanical comparison of occipitoatlantal screw fixation techniques. J Neurosurg Spine 8:1431522008

  • 14

    Belmont PJ JrKlemme WRDhawan APolly DW Jr: In vivo accuracy of thoracic pedicle screws. Spine (Phila Pa 1976) 26:234023462001

  • 15

    Ben-David B: Spinal cord monitoring. Orthop Clin North Am 19:4274481988

  • 16

    Bernstein RMHall JE: Solid rod short segment anterior fusion in thoracolumbar scoliosis. J Pediatr Orthop B 7:1241311998

  • 17

    Bess SAkbarnia BAThompson GHSponseller PDShah SAEl Sebaie H: Complications of growing-rod treatment for early-onset scoliosis: analysis of one hundred and forty patients. J Bone Joint Surg Am 92:253325432010

  • 18

    Betz RRKim JD’Andrea LPMulcahey MJBalsara RKClements DH: An innovative technique of vertebral body stapling for the treatment of patients with adolescent idiopathic scoliosis: a feasibility, safety, and utility study. Spine (Phila Pa 1976) 28:S255S2652003

  • 19

    Betz RRRanade ASamdani AFChafetz RD’Andrea LPGaughan JP: Vertebral body stapling: a fusionless treatment option for a growing child with moderate idiopathic scoliosis. Spine (Phila Pa 1976) 35:1691762010

  • 20

    Boos NWebb JK: Pedicle screw fixation in spinal disorders: a European view. Eur Spine J 6:2181997

  • 21

    Borne GMBedou GLPinaudeau M: Treatment of pedicular fractures of the axis. A clinical study and screw fixation technique. J Neurosurg 60:88931984

  • 22

    Boucher HH: A method of spinal fusion. J Bone Joint Surg Br 41-B:2482591959

  • 23

    Braun JTHoffman MAkyuz EOgilvie JWBrodke DSBachus KN: Mechanical modulation of vertebral growth in the fusionless treatment of progressive scoliosis in an experimental model. Spine (Phila Pa 1976) 31:131413202006

  • 24

    Brenner DElliston CHall EBerdon W: Estimated risks of radiation-induced fatal cancer from pediatric CT. AJR Am J Roentgenol 176:2892962001

  • 25

    Brockmeyer DLYork JEApfelbaum RI: Anatomical suitability of C1-2 transarticular screw placement in pediatric patients. J Neurosurg 92 (1 Suppl):7112000

  • 26

    Burton DCAsher MALai SM: Scoliosis correction maintenance in skeletally immature patients with idiopathic scoliosis. Is anterior fusion really necessary? Spine (Phila Pa 1976) 25:61682000

  • 27

    Campbell RM Jr: VEPTR: past experience and the future of VEPTR principles. Eur Spine J 22 (Suppl 2):S106S1172013

  • 28

    Capen DAGarland DEWaters RL: Surgical stabilization of the cervical spine. A comparative analysis of anterior and posterior spine fusions. Clin Orthop Relat Res (196):2292371985

  • 29

    Carlioz HOuaknine M: [Neurologic complications of surgery of the spine in children.] Chirurgie 120:26301994–1995 (Fr)

  • 30

    Casey ATHayward RDHarkness WFCrockard HA: The use of autologous skull bone grafts for posterior fusion of the upper cervical spine in children. Spine (Phila Pa 1976) 20:221722201995

  • 31

    Chadduck WMBoop FA: Use of full-thickness calvarial bone grafts for cervical spinal fusions in pediatric patients. Pediatr Neurosurg 20:1071121994

  • 32

    Chamoun RBRelyea KMJohnson KKWhitehead WECurry DJLuerssen TG: Use of axial and subaxial translaminar screw fixation in the management of upper cervical spinal instability in a series of 7 children. Neurosurgery 64:7347392009

  • 33

    Chern JJChamoun RBWhitehead WECurry DJLuerssen TGJea A: Computed tomography morphometric analysis for axial and subaxial translaminar screw placement in the pediatric cervical spine. J Neurosurg Pediatr 3:1211282009

  • 34

    Chern JJRelyea KJea A: Instrumentation and stabilization of the pediatric spine: technical nuances and age-specific considerations in Quinones-Hinojosa A (ed): Schmidek & Sweet: Operative Neurosurgical Techniques: Indications Methods and Results ed 6. Philadelphia: Elsevier Saunders2012 Vol 1 pp 759767

  • 35

    Coe JDWarden KESutterlin CE IIIMcAfee PC: Biomechanical evaluation of cervical spinal stabilization methods in a human cadaveric model. Spine (Phila Pa 1976) 14:112211311989

  • 36

    Deen HGBirch BDWharen REReimer R: Lateral mass screw-rod fixation of the cervical spine: a prospective clinical series with 1-year follow-up. Spine J 3:4894952003

  • 37

    Desai SKBrayton AChua VBLuerssen TGJea A: The lasting legacy of Paul Randall Harrington to pediatric spine surgery: historical vignette. J Neurosurg Spine 18:1701772013

  • 38

    Desai SKSayama CVener DBrayton ABriceño VLuerssen TG: The feasibility and safety of using sublaminar polyester bands in hybrid spinal constructs in children and transitional adults for neuromuscular scoliosis. J Neurosurg Pediatr 15:3283372015

  • 39

    Dickman CASonntag VK: Posterior C1-C2 transarticular screw fixation for atlantoaxial arthrodesis. Neurosurgery 43:2752811998

  • 40

    DiFiore JWWilson JM: Lung development. Semin Pediatr Surg 3:2212321994

  • 41

    Dohin BDubousset JF: Prevention of the crankshaft phenomenon with anterior spinal epiphysiodesis in surgical treatment of severe scoliosis of the younger patient. Eur Spine J 3:1651681994

  • 42

    Du JYAichmair AKueper JWright TLebl DR: Biomechanical analysis of screw constructs for atlantoaxial fixation in cadavers: a systematic review and meta-analysis. J Neurosurg Spine 22:1511612015

  • 43

    Dubousset JHerring JAShufflebarger H: The crankshaft phenomenon. J Pediatr Orthop 9:5415501989

  • 44

    Dvorak MFKwon BKFisher CGEiserloh HL IIIBoyd MWing PC: Effectiveness of titanium mesh cylindrical cages in anterior column reconstruction after thoracic and lumbar vertebral body resection. Spine (Phila Pa 1976) 28:9029082003

  • 45

    Farey IDNadkarni SSmith N: Modified Gallie technique versus transarticular screw fixation in C1-C2 fusion. Clin Orthop Relat Res (359):1261351999

  • 46

    Faure AMonteiro RHamel ORaoul SSzapiro JAlcheikh M: Inverted-hook occipital clamp system in occipitocervical fixation. Technical note. J Neurosurg 97 (1 Suppl):1351412002

  • 47

    Fehlings MGCooper PRErrico TJ: Posterior plates in the management of cervical instability: long-term results in 44 patients. J Neurosurg 81:3413491994

  • 48

    Garber STBrockmeyer DL: Management of subaxial cervical instability in very young or small-for-age children using a static single-screw anterior cervical plate: indications, results, and long-term follow-up. J Neurosurg Spine 24:8928962016

  • 49

    Ghiselli GWang JCBhatia NNHsu WKDawson EG: Adjacent segment degeneration in the lumbar spine. J Bone Joint Surg Am 86-A:1497–15032004

  • 50

    Gill KPaschal SCorin JAshman RBucholz RW: Posterior plating of the cervical spine. A biomechanical comparison of different posterior fusion techniques. Spine (Phila Pa 1976) 13:8138161988

  • 51

    Girardi FPBoachie-Adjei ORawlins BA: Safety of sublaminar wires with Isola instrumentation for the treatment of idiopathic scoliosis. Spine (Phila Pa 1976) 25:6916952000

  • 52

    Gluf WMBrockmeyer DL: Atlantoaxial transarticular screw fixation: a review of surgical indications, fusion rate, complications, and lessons learned in 67 pediatric patients. J Neurosurg Spine 2:1641692005

  • 53

    Goel ALaheri V: Plate and screw fixation for atlanto-axial subluxation. Acta Neurochir (Wien) 129:47531994

  • 54

    Goldstein HENeira JABanu MAldana PRBraga BPBrockmeyer DL: Growth and alignment of the pediatric subaxial cervical spine following rigid instrumentation and fusion: a multicenter study of the Pediatric Craniocervical Society. J Neurosurg Pediatr 22:81882018

  • 55

    Grob DDvorak JPanjabi MMAntinnes JA: The role of plate and screw fixation in occipitocervical fusion in rheumatoid arthritis. Spine (Phila Pa 1976) 19:254525511994

  • 56

    Haher TRYeung AWCaruso SAMerola AAShin TZipnick RI: Occipital screw pullout strength. A biomechanical investigation of occipital morphology. Spine (Phila Pa 1976) 24:591999

  • 57

    Harms JMelcher RP: Posterior C1-C2 fusion with polyaxial screw and rod fixation. Spine (Phila Pa 1976) 26:246724712001

  • 58

    Harrington PR: The history and development of Harrington instrumentation. Clin Orthop Relat Res (93):1101121973

  • 59

    Harrington PR: Treatment of scoliosis. Correction and internal fixation by spine instrumentation. J Bone Joint Surg Am 44-A:5916101962

  • 60

    Hedequist DJHall JEEmans JB: The safety and efficacy of spinal instrumentation in children with congenital spine deformities. Spine (Phila Pa 1976) 29:208120872004

  • 61

    Hefti FLMcMaster MJ: The effect of the adolescent growth spurt on early posterior spinal fusion in infantile and juvenile idiopathic scoliosis. J Bone Joint Surg Br 65:2472541983

  • 62

    Herring JAWenger DR: Segmental spinal instrumentation: a preliminary report of 40 consecutive cases. Spine (Phila Pa 1976) 7:2852981982

  • 63

    Heywood AWLearmonth IDThomas M: Internal fixation for occipito-cervical fusion. J Bone Joint Surg Br 70:7087111988

  • 64

    Holland CMKebriaei MAWrubel DM: Posterior cervical spinal fusion in a 3-week-old infant with a severe subaxial distraction injury. J Neurosurg Pediatr 17:3533562016

  • 65

    Howington JUKruse JJAwasthi D: Surgical anatomy of the C-2 pedicle. J Neurosurg 95 (1 Suppl):88922001

  • 66

    Hwang SWGressot LVRangel-Castilla LWhitehead WECurry DJBollo RJ: Outcomes of instrumented fusion in the pediatric cervical spine. J Neurosurg Spine 17:3974092012

  • 67

    Jain AKebaish KMSponseller PD: Factors associated with use of bone morphogenetic protein during pediatric spinal fusion surgery: an analysis of 4817 patients. J Bone Joint Surg Am 95:126512702013

  • 68

    Jea ATaylor MDDirks PBKulkarni AVRutka JTDrake JM: Incorporation of C-1 lateral mass screws in occipitocervical and atlantoaxial fusions for children 8 years of age or younger. Technical note. J Neurosurg 107 (2 Suppl):1781832007

  • 69

    Jeanneret BMagerl F: Primary posterior fusion C1/2 in odontoid fractures: indications, technique, and results of transarticular screw fixation. J Spinal Disord 5:4644751992

  • 70

    Jenks MCraig JHiggins JWillits IBarata TWood H: The MAGEC system for spinal lengthening in children with scoliosis: a NICE medical technology guidance. Appl Health Econ Health Policy 12:5875992014

  • 71

    Johnson KTAl-Holou WNAnderson RCWilson TJKarnati TIbrahim M: Morphometric analysis of the developing pediatric cervical spine. J Neurosurg Pediatr 18:3773892016

  • 72

    Johnston CE IIHappel LT JrNorris RBurke SWKing AGRoberts JM: Delayed paraplegia complicating sublaminar segmental spinal instrumentation. J Bone Joint Surg Am 68:5565631986

  • 73

    Kamimura MEbara SItoh HTateiwa YKinoshita TTakaoka K: Accurate pedicle screw insertion under the control of a computer-assisted image guiding system: laboratory test and clinical study. J Orthop Sci 4:1972061999

  • 74

    Kennedy BCD’Amico RSYoungerman BEMcDowell MMHooten KGCouture D: Long-term growth and alignment after occipitocervical and atlantoaxial fusion with rigid internal fixation in young children. J Neurosurg Pediatr 17:941022016

  • 75

    Kleinerman RA: Cancer risks following diagnostic and therapeutic radiation exposure in children. Pediatr Radiol 36 (Suppl 2):1211252006

  • 76

    Klimo P JrAstur NGabrick KWarner WC JrMuhlbauer MS: Occipitocervical fusion using a contoured rod and wire construct in children: a reappraisal of a vintage technique. J Neurosurg Pediatr 11:1601692013

  • 77

    Kou ITakahashi YJohnson TATakahashi AGuo LDai J: Genetic variants in GPR126 are associated with adolescent idiopathic scoliosis. Nat Genet 45:6766792013

  • 78

    Krag MHBeynnon BDPope MHFrymoyer JWHaugh LDWeaver DL: An internal fixator for posterior application to short segments of the thoracic, lumbar, or lumbosacral spine. Design and testing. Clin Orthop Relat Res (203):75981986

  • 79

    Kurtz SMDevine JN: PEEK biomaterials in trauma, orthopedic, and spinal implants. Biomaterials 28:484548692007

  • 80

    Kwan KYHAlanay AYazici MDemirkiran GHelenius INnadi C: Unplanned reoperations in magnetically controlled growing rod surgery for early onset scoliosis with a minimum of two-year follow-up. Spine (Phila Pa 1976) 42:E1410E14142017

  • 81

    Lapinksy ASRichards BS: Preventing the crankshaft phenomenon by combining anterior fusion with posterior instrumentation. Does it work? Spine (Phila Pa 1976) 20:139213981995

  • 82

    Larson ANPolly DW JrGuidera KJMielke CHSantos ERLedonio CG: The accuracy of navigation and 3D image-guided placement for the placement of pedicle screws in congenital spine deformity. J Pediatr Orthop 32:e23e292012

  • 83

    Larson ANSantos ERPolly DW JrLedonio CGSembrano JNMielke CH: Pediatric pedicle screw placement using intraoperative computed tomography and 3-dimensional image-guided navigation. Spine (Phila Pa 1976) 37:E188E1942012

  • 84

    Lee CSNachemson AL: The crankshaft phenomenon after posterior Harrington fusion in skeletally immature patients with thoracic or thoracolumbar idiopathic scoliosis followed to maturity. Spine (Phila Pa 1976) 22:58671997

  • 85

    Lee SMSuk SIChung ER: Direct vertebral rotation: a new technique of three-dimensional deformity correction with segmental pedicle screw fixation in adolescent idiopathic scoliosis. Spine (Phila Pa 1976) 29:3433492004

  • 86

    Lenke LGBridwell KH: Mesh cages in idiopathic scoliosis in adolescents. Clin Orthop Relat Res (394):981082002

  • 87

    Leonard JRWright NM: Pediatric atlantoaxial fixation with bilateral, crossing C-2 translaminar screws. Technical note. J Neurosurg 104 (1 Suppl):59632006

  • 88

    Li WLi YZhang LGuo HTian DLi Y: AKAP2 identified as a novel gene mutated in a Chinese family with adolescent idiopathic scoliosis. J Med Genet 53:4884932016

  • 89

    Liang JLi SXu DZhuang QRen ZChen X: Risk factors for predicting complications associated with growing rod surgery for early-onset scoliosis. Clin Neurol Neurosurg 136:15192015

  • 90

    Liljenqvist ULepsien UHackenberg LNiemeyer THalm H: Comparative analysis of pedicle screw and hook instrumentation in posterior correction and fusion of idiopathic thoracic scoliosis. Eur Spine J 11:3363432002

  • 91

    Liljenqvist URHalm HFLink TM: Pedicle screw instrumentation of the thoracic spine in idiopathic scoliosis. Spine (Phila Pa 1976) 22:223922451997

  • 92

    Lonstein JEWinter RBMoe JHBradford DSChou SNPinto WC: Neurologic deficits secondary to spinal deformity. A review of the literature and report of 43 cases. Spine (Phila Pa 1976) 5:3313551980

  • 93

    Luque ER: Segmental spinal instrumentation for correction of scoliosis. Clin Orthop Relat Res (163):1921981982

  • 94

    Madawi AACasey ATSolanki GATuite GVeres RCrockard HA: Radiological and anatomical evaluation of the atlantoaxial transarticular screw fixation technique. J Neurosurg 86:9619681997

  • 95

    Majd MECastro FP JrHolt RT: Anterior fusion for idiopathic scoliosis. Spine (Phila Pa 1976) 25:6967022000

  • 96

    Marchesi DGMichel MLowery GLAebi M: Anterior transpedicular fixation of the lower thoracic and lumbar spine. Experimental verification using a new direction finder. Spine (Phila Pa 1976) 18:4614651993

  • 97

    Martinez-Del-Campo ETurner JDRangel-Castilla LSoriano-Baron HKalb STheodore N: Pediatric occipitocervical fixation: radiographic criteria, surgical technique, and clinical outcomes based on experience of a single surgeon. J Neurosurg Pediatr 18:4524622016

  • 98

    Martinez-Del-Campo ETurner JDSoriano-Baron HNewcomb AGKalb STheodore N: Pediatric occipitocervical fusion: long-term radiographic changes in curvature, growth, and alignment. J Neurosurg Pediatr 18:6446522016

  • 99

    McCarthy REMcCullough FL: Shilla growth guidance for early-onset scoliosis: results after a minimum of five years of follow-up. J Bone Joint Surg Am 97:157815842015

  • 100

    Mehlman CTAraghi ARoy DR: Hyphenated history: the Hueter-Volkmann law. Am J Orthop 26:7988001997

  • 101

    Mente PLStokes IASpence HAronsson DD: Progression of vertebral wedging in an asymmetrically loaded rat tail model. Spine (Phila Pa 1976) 22:129212961997

  • 102

    Merloz PTonetti JPittet LCoulomb MLavallée STroccaz J: Computer-assisted spine surgery. Comput Aided Surg 3:2973051998

  • 103

    Montesano PXJauch EJonsson H Jr: Anatomic and biomechanical study of posterior cervical spine plate arthrodesis: an evaluation of two different techniques of screw placement. J Spinal Disord 5:3013051992

  • 104

    Myles RTFong BEsses SIHipp JA: Radiographic verification of pedicle screw pilot hole placement using Kirshner wires versus beaded wires. Spine (Phila Pa 1976) 24:4764801999

  • 105

    Nachlas IWBorden JN: The cure of experimental scoliosis by directed growth control. J Bone Joint Surg Am 33-A:24341951

  • 106

    Nadim YLu JSabry FFEbraheim N: Occipital screws in occipitocervical fusion and their relation to the venous sinuses: an anatomic and radiographic study. Orthopedics 23:7177192000

  • 107

    Newton POFarnsworth CLFaro FDMahar ATOdell TRMohamad F: Spinal growth modulation with an anterolateral flexible tether in an immature bovine model: disc health and motion preservation. Spine (Phila Pa 1976) 33:7247332008

  • 108

    Newton POFricka KBLee SSFarnsworth CLCox TGMahar AT: Asymmetrical flexible tethering of spine growth in an immature bovine model. Spine (Phila Pa 1976) 27:6896932002

  • 109

    Ni BGuo XXie NLu XYuan WLi S: Bilateral atlantoaxial transarticular screws and atlas laminar hooks fixation for pediatric atlantoaxial instability. Spine (Phila Pa 1976) 35:E1367E13722010

  • 110

    Odent TBou Ghosn RDusabe JPZerah MGlorion C: Internal fixation with occipital hooks construct for occipito-cervical arthrodesis. Results in 14 young or small children. Eur Spine J 24:941002015

  • 111

    Ogura YKou IMiura STakahashi AXu LTakeda K: A functional SNP in BNC2 is associated with adolescent idiopathic scoliosis. Am J Hum Genet 97:3373422015

  • 112

    Papagelopoulos PJCurrier BLStone JGrabowski JJLarson DRFisher DR: Biomechanical evaluation of occipital fixation. J Spinal Disord 13:3363442000

  • 113

    Parisini PDi Silvestre MGreggi TBianchi G: C1-C2 posterior fusion in growing patients: long-term follow-up. Spine (Phila Pa 1976) 28:5665722003

  • 114

    Patten SAMargaritte-Jeannin PBernard JCAlix ELabalme ABesson A: Functional variants of POC5 identified in patients with idiopathic scoliosis. J Clin Invest 125:112411282015

  • 115

    Pennig DBrug E: A target device for placement of implants in the thoracolumbar pedicles. J Bone Joint Surg Br 72:8868881990

  • 116

    Quinn JCPatel NVTyagi R: Hybrid lateral mass screw sublaminar wire construct: A salvage technique for posterior cervical fixation in pediatric spine surgery. J Clin Neurosci 25:1181212016

  • 117

    Rajasekaran SKanna PRShetty AP: Safety of cervical pedicle screw insertion in children: a clinicoradiological evaluation of computer-assisted insertion of 51 cervical pedicle screws including 28 subaxial pedicle screws in 16 children. Spine (Phila Pa 1976) 37:E216E2232012

  • 118

    Rangel-Castilla LHwang SWWhitehead WECurry DJLuerssen TGJea A: Surgical treatment of thoracic Pott disease in a 3-year-old child, with vertebral column resection and posterior-only circumferential reconstruction of the spinal column: case report. J Neurosurg Pediatr 9:4474512012

  • 119

    Resnick DKLapsiwala STrost GR: Anatomic suitability of the C1-C2 complex for pedicle screw fixation. Spine (Phila Pa 1976) 27:149414982002

  • 120

    Richards BSJohnston CE II: Cotrel-Dubousset instrumentation for adolescent idiopathic scoliosis. Orthopedics 10:6496541987

  • 121

    Richardson ABTaylor MLMurphree B: TSRH instrumentation: evolution of a new system. Part 1. Orthop Nurs 9:15211990

  • 122

    Riis JLehman RRPerera RAQuinn JRRinehart PTuten HR: A retrospective comparison of intraoperative CT and fluoroscopy evaluating radiation exposure in posterior spinal fusions for scoliosis. Patient Saf Surg 11:322017

  • 123

    Roberts DADoherty BJHeggeness MH: Quantitative anatomy of the occiput and the biomechanics of occipital screw fixation. Spine (Phila Pa 1976) 23:110011081998

  • 124

    Roy-Camille RSaillant GLaville CBenazet JP: Treatment of lower cervical spinal injuries—C3 to C7. Spine (Phila Pa 1976) 17 (10 Suppl):S442S4461992

  • 125

    Roy-Camille RSaillant GMazel C: Internal fixation of the lumbar spine with pedicle screw plating. Clin Orthop Relat Res (203):7171986

  • 126

    Roy-Camille RSaillant GMazel C: Plating of thoracic, thoracolumbar, and lumbar injuries with pedicle screw plates. Orthop Clin North Am 17:1471591986

  • 127

    Ryken TCGoel VKClausen JDTraynelis VC: Assessment of unicortical and bicortical fixation in a quasistatic cadaveric model. Role of bone mineral density and screw torque. Spine (Phila Pa 1976) 20:186118671995

  • 128

    Samdani AFAmes RJKimball JSPahys JMGrewal HPelletier GJ: Anterior vertebral body tethering for idiopathic scoliosis: two-year results. Spine (Phila Pa 1976) 39:168816932014

  • 129

    Sanders JOLittle DGRichards BS: Prediction of the crankshaft phenomenon by peak height velocity. Spine (Phila Pa 1976) 22:135213571997

  • 130

    Savage JGFulkerson DHSen ANThomas JGJea A: Fixation with C-2 laminar screws in occipitocervical or C1-2 constructs in children 5 years of age or younger: a series of 18 patients. J Neurosurg Pediatr 14:87932014

  • 131

    Sayama CHadley CMonaco GNSen ABrayton ABriceño V: The efficacy of routine use of recombinant human bone morphogenetic protein-2 in occipitocervical and atlantoaxial fusions of the pediatric spine: a minimum of 12 months’ follow-up with computed tomography. J Neurosurg Pediatr 16:14202015

  • 132

    Sayama CWillsey MChintagumpala MBrayton ABriceño VRyan SL: Routine use of recombinant human bone morphogenetic protein-2 in posterior fusions of the pediatric spine and incidence of cancer. J Neurosurg Pediatr 16:4132015

  • 133

    Seitz HMarlovits SSchwendenwein IMüller EVécsei V: Biocompatibility of polyethylene terephthalate (Trevira hochfest) augmentation device in repair of the anterior cruciate ligament. Biomaterials 19:1891961998

  • 134

    Sekhon LH: Posterior cervical lateral mass screw fixation: analysis of 1026 consecutive screws in 143 patients. J Spinal Disord Tech 18:2973032005

  • 135

    Sharma SLondono DEckalbar WLGao XZhang DMauldin K: A PAX1 enhancer locus is associated with susceptibility to idiopathic scoliosis in females. Nat Commun 6:64522015

  • 136

    Singh BCree A: Laminar screw fixation of the axis in the pediatric population: a series of eight patients. Spine (Phila Pa 1976) J 15:e17e252015

  • 137

    Singh HRahimi SYYeh DJFloyd D: History of posterior thoracic instrumentation. Neurosurg Focus 16(1):E112004

  • 138

    Sinha SJagetia AAher RBButte MK: Occiput/C1-C2 fixations using intra-laminar screw of axis—A long-term follow-up. Br J Neurosurg 29:2602642015

  • 139

    Sinha SJagetia ABhausaheb ARButte MVJain R: Rigid variety occiput/C1-C2-C3 internal fixation in pediatric population. Childs Nerv Syst 30:2572692014

  • 140

    Stauffer ESKelly EG: Fracture-dislocations of the cervical spine. Instability and recurrent deformity following treatment by anterior interbody fusion. J Bone Joint Surg Am 59:45481977

  • 141

    Stevens DBBeard C: Segmental spinal instrumentation for neuromuscular spinal deformity. Clin Orthop Relat Res (242):1641681989

  • 142

    Strickland BASayama CBriceño VLam SKLuerssen TGJea A: Use of subtransverse process polyester bands in pediatric spine surgery: a case series of 4 patients with a minimum of 12 months’ follow-up. J Neurosurg Pediatr 17:2082142016

  • 143

    Suk SIKim WJLee SMKim JHChung ER: Thoracic pedicle screw fixation in spinal deformities: are they really safe? Spine (Phila Pa 1976) 26:204920572001

  • 144

    Sutterlin CE IIIMcAfee PCWarden KERey RM JrFarey ID: A biomechanical evaluation of cervical spinal stabilization methods in a bovine model. Static and cyclical loading. Spine (Phila Pa 1976) 13:7958021988

  • 145

    Tauchi RImagama SIto ZAndo KMuramoto AMatsui H: Surgical treatment for chronic atlantoaxial rotatory fixation in children. J Pediatr Orthop B 22:4044082013

  • 146

    Toyama YMatsumoto MChiba KAsazuma TSuzuki NFujimura Y: Realignment of postoperative cervical kyphosis in children by vertebral remodeling. Spine (Phila Pa 1976) 19:256525701994

  • 147

    Turi MJohnston CE IIRichards BS: Anterior correction of idiopathic scoliosis using TSRH instrumentation. Spine (Phila Pa 1976) 18:4174221993

  • 148

    Ulrich CWoersdoerfer OKalff RClaes LWilke HJ: Biomechanics of fixation systems to the cervical spine. Spine (Phila Pa 1976) 16 (3 Suppl):S4S91991

  • 149

    Vaccaro ARBalderston RA: Anterior plate instrumentation for disorders of the subaxial cervical spine. Clin Orthop Relat Res (335):1121211997

  • 150

    Van de Kelft ECosta FVan der Planken DSchils F: A prospective multicenter registry on the accuracy of pedicle screw placement in the thoracic, lumbar, and sacral levels with the use of the O-arm imaging system and StealthStation Navigation. Spine (Phila Pa 1976) 37:E1580E15872012

  • 151

    Vlach OGrosman RRouchal M: [Instrumentation of idiopathic scolioses by isola and miami-moss systems.] Acta Chir Orthop Traumatol Cech 67:3133152000 (Czech)

  • 152

    Wang JCNuccion SLFeighan JECohen BDorey FJScoles PV: Growth and development of the pediatric cervical spine documented radiographically. J Bone Joint Surg Am 83-A:121212182001

  • 153

    Watanabe KUno KSuzuki TKawakami NTsuji TYanagida H: Risk factors for complications associated with growing-rod surgery for early-onset scoliosis. Spine (Phila Pa 1976) 38:E464E4682013

  • 154

    Wimmer CGluch HFranzreb MOgon M: Predisposing factors for infection in spine surgery: a survey of 850 spinal procedures. J Spinal Disord 11:1241281998

  • 155

    Winegar CDLawrence JPFriel BCFernandez CHong JMaltenfort M: A systematic review of occipital cervical fusion: techniques and outcomes. J Neurosurg Spine 13:5162010

  • 156

    Winter RBLonstein JE: Congenital scoliosis with posterior spinal arthrodesis T2-L3 at age 3 years with 41-year follow-up. A case report. Spine (Phila Pa 1976) 24:1941971999

  • 157

    Winter RBMoe JH: The results of spinal arthrodesis for congenital spinal deformity in patients younger than five years old. J Bone Joint Surg Am 64:4194321982

  • 158

    Winter RBMoe JHLonstein JE: Posterior spinal arthrodesis for congenital scoliosis. An analysis of the cases of two hundred and ninety patients, five to nineteen years old. J Bone Joint Surg Am 66:118811971984

  • 159

    Wittenberg RHShea MSwartz DELee KSWhite AA IIIHayes WC: Importance of bone mineral density in instrumented spine fusions. Spine (Phila Pa 1976) 16:6476521991

  • 160

    Wright NM: Posterior C2 fixation using bilateral, crossing C2 laminar screws: case series and technical note. J Spinal Disord Tech 17:1581622004

  • 161

    Wright NM: Translaminar rigid screw fixation of the axis. Technical note. J Neurosurg Spine 3:4094142005

  • 162

    Zhou TChen CXu CZhou HGao BSu D: Mutant MAPK7-induced idiopathic scoliosis is linked to impaired osteogenesis. Cell Physiol Biochem 48:8808902018

  • 163

    Zhu ZTang NLXu LQin XMao SSong Y: Genome-wide association study identifies new susceptibility loci for adolescent idiopathic scoliosis in Chinese girls. Nat Commun 6:83552015

If the inline PDF is not rendering correctly, you can download the PDF file here.

Article Information

Correspondence Andrew Jea: Goodman Campbell Brain and Spine, Indiana University School of Medicine, Indianapolis, IN. ajea@goodmancampbell.com.

INCLUDE WHEN CITING DOI: 10.3171/2018.10.PEDS18327.

Disclosures The authors report no conflict of interest concerning the materials or methods used in this study or the findings specified in this paper.

© AANS, except where prohibited by US copyright law.

Headings

Figures

  • View in gallery

    Occipital fixation. Tapping (A) and placement (B) of occipital screws. The stop-drill technique, which consists of triangulating toward the midline, performed slowly until penetration of the inner table of the skull, is routinely used to prevent dural and sinus laceration. Right- and left-sided screw trajectories are staggered to prevent screw paths from intersecting. Screws are typically placed between the inferior and superior nuchal lines. Screws may be placed in a unicortical fashion near the superior nuchal line to prevent penetration of the transverse sinus. Image created by Katherine Relyea, MS, CMI, and printed with permission from Baylor College of Medicine; first appeared in Chern JJ, et al: Instrumentation and stabilization of the pediatric spine: technical nuances and age-specific considerations, in Quinones-Hinojosa A (ed): Schmidek & Sweet: Operative Neurosurgical Techniques: Indications, Methods, and Results, ed 6. Philadelphia: Elsevier Saunders, 2012, Vol 1, pp 759–767.

  • View in gallery

    C1–2 transarticular screw technique. Note the screw proximity to the vertebral arteries, making this a very challenging stabilization technique in children. Image created by Katherine Relyea, MS, CMI, and printed with permission from Baylor College of Medicine; first appeared in Chern JJ, et al: Instrumentation and stabilization of the pediatric spine: technical nuances and age-specific considerations, in Quinones-Hinojosa A (ed): Schmidek & Sweet: Operative Neurosurgical Techniques: Indications, Methods, and Results, ed 6. Philadelphia: Elsevier Saunders, 2012, Vol 1, pp 759–767.

  • View in gallery

    C1 lateral mass crew technique. The entry point of the C1 lateral mass screw is deep at the confluence of the C1 lamina and C1 lateral mass to avoid the vertebral artery in the more superficial sulcus arteriosus. The medial surface of the C1 lateral mass should be palpated as an important landmark. The entry point should be 2–3 mm from the medial aspect of the C1 lateral mass. The lateral aspect of the lateral mass should be avoided, as this is where the vertebral artery resides. Bicortical screw purchase is desired to increase pullout strength. To help with exposure of the bony landmarks for C1 lateral mass screw placement, we recommend sectioning the C2 nerve root. Judicious (and continuous) bipolar coagulation of the venous plexus surrounding the C2 nerve root should be performed. Stepwise division of the C2 nerve root proximal to the dorsal root ganglion. There is no reason to rush this portion of the procedure if acceptable blood loss is a goal of surgery. Image created by Katherine Relyea, MS, CMI, and printed with permission from Baylor College of Medicine; first appeared in Chern JJ, et al: Instrumentation and stabilization of the pediatric spine: technical nuances and age-specific considerations, in Quinones-Hinojosa A (ed): Schmidek & Sweet: Operative Neurosurgical Techniques: Indications, Methods, and Results, ed 6. Philadelphia: Elsevier Saunders, 2012, Vol 1, pp 759–767.

  • View in gallery

    C2 pars/pedicle screw technique. Note the proximity of the spinal canal and vertebral artery in comparison with the translaminar screw in Fig. 5. Image created by Katherine Relyea, MS, CMI, and printed with permission from Baylor College of Medicine; first appeared in Chern JJ, et al: Instrumentation and stabilization of the pediatric spine: technical nuances and age-specific considerations, in Quinones-Hinojosa A (ed): Schmidek & Sweet: Operative Neurosurgical Techniques: Indications, Methods, and Results, ed 6. Philadelphia: Elsevier Saunders, 2012, Vol 1, pp 759–767.

  • View in gallery

    Translaminar screw technique. C2 translaminar screw fixation is a safe technique for rigid fixation and avoids the vertebral arteries. A potential drawback to this technique is breach of the nonvisualized ventral laminar wall leading to dural laceration, CSF leak, or spinal cord injury. Wright’s method for placing laminar screws can be modified with a small exit window in the dorsal cortex of the lamina at the laminofacet line. This exit window allows the surgeon to visualize the tip of the screw to ensure that it has not penetrated the ventral laminar cortex. Careful study of the preoperative CT scan can indicate screw length and width. Image created by Katherine Relyea, MS, CMI, and printed with permission from Baylor College of Medicine; first appeared in Chern JJ, et al: Instrumentation and stabilization of the pediatric spine: technical nuances and age-specific considerations, in Quinones-Hinojosa A (ed): Schmidek & Sweet: Operative Neurosurgical Techniques: Indications, Methods, and Results, ed 6. Philadelphia: Elsevier Saunders, 2012, Vol 1, pp 759–767.

  • View in gallery

    C3–7 lateral mass screw technique. The entire lateral mass of the subaxial cervical spine should be exposed at each level. On the dorsal square face of the lateral mass, an entry point 1 mm medial and 1 mm caudal from the midpoint (dot) should be selected. The drill and screw trajectory should be directed “up and out” toward the deep superior and ventral corner of the lateral mass box (about 20° lateral and 20° rostral) to avoid vertebral artery and nerve root injury, respectively. Image created by Katherine Relyea, MS, CMI, and printed with permission from Baylor College of Medicine; first appeared in Chern JJ, et al: Instrumentation and stabilization of the pediatric spine: technical nuances and age-specific considerations, in Quinones-Hinojosa A (ed): Schmidek & Sweet: Operative Neurosurgical Techniques: Indications, Methods, and Results, ed 6. Philadelphia: Elsevier Saunders, 2012, Vol 1, pp 759–767.

  • View in gallery

    Thoracic and lumbar pedicle screw technique. Pedicle screw placement may start at the confluence of the pars interarticularis and transverse process. Rostral-caudal and mediolateral angulation of the pedicles should be studied prior to surgery at each vertebral level to help guide screw trajectory. There may be a role for intraoperative image guidance in the placement of pedicle screws. Image created by Katherine Relyea, MS, CMI, and printed with permission from Baylor College of Medicine; first appeared in Chern JJ, et al: Instrumentation and stabilization of the pediatric spine: technical nuances and age-specific considerations, in Quinones-Hinojosa A (ed): Schmidek & Sweet: Operative Neurosurgical Techniques: Indications, Methods, and Results, ed 6. Philadelphia: Elsevier Saunders, 2012, Vol 1, pp 759–767.

  • View in gallery

    Sublaminar wire/band technique. The ligamentum flavum is resected in the interlaminar spaces above and below the lamina of interest. We are careful not to resect too much of the lamina itself. A gentle curve for the malleable semirigid tip of the wire or polyester band is created. The tip is passed gently underneath the lamina from caudal to rostral. A hemostat or nerve hook is used to snare the tip of the wire or polyester band. Through use of a push-pull technique to avoid a loop of wire or band compressing the thecal sac and spinal cord, the wire or band is progressively passed underneath the lamina until the semirigid tip has fully traversed the lamina. Once all sublaminar wires or bands have been passed, each wire or band is secured to the rod. Sequential tensioning may then be applied to produce a translation of the spine toward the rod. Image created by Katherine Relyea, MS, CMI, and printed with permission from Baylor College of Medicine; first appeared in Chern JJ, et al: Instrumentation and stabilization of the pediatric spine: technical nuances and age-specific considerations, in Quinones-Hinojosa A (ed): Schmidek & Sweet: Operative Neurosurgical Techniques: Indications, Methods, and Results, ed 6. Philadelphia: Elsevier Saunders, 2012, Vol 1, pp 759–767.

References

1

Abumi KItoh HTaneichi HKaneda K: Transpedicular screw fixation for traumatic lesions of the middle and lower cervical spine: description of the techniques and preliminary report. J Spinal Disord 7:19281994

2

Abumi KKaneda K: Pedicle screw fixation for nontraumatic lesions of the cervical spine. Spine (Phila Pa 1976) 22:185318631997

3

Acharya SSarafoglou KLaQuaglia MLindsley SGerald WWollner N: Thyroid neoplasms after therapeutic radiation for malignancies during childhood or adolescence. Cancer 97:239724032003

4

Adeloye AKattan KRSilverman FN: Thickness of the normal skull in the American blacks and whites. Am J Phys Anthropol 43:23301975

5

Ahmed RTraynelis VCMenezes AH: Fusions at the craniovertebral junction. Childs Nerv Syst 24:120912242008

6

Akamaru TKawahara NTsuchiya HKobayashi TMurakami HTomita K: Healing of autologous bone in a titanium mesh cage used in anterior column reconstruction after total spondylectomy. Spine (Phila Pa 1976) 27:E329E3332002

7

Amiot LPLang KPutzier MZippel HLabelle H: Comparative results between conventional and computer-assisted pedicle screw installation in the thoracic, lumbar, and sacral spine. Spine (Phila Pa 1976) 25:6066142000

8

Anderson RCKan PGluf WMBrockmeyer DL: Long-term maintenance of cervical alignment after occipitocervical and atlantoaxial screw fixation in young children. J Neurosurg 105 (1 Suppl):55612006

9

Anderson RCRagel BTMocco JBohman LEBrockmeyer DL: Selection of a rigid internal fixation construct for stabilization at the craniovertebral junction in pediatric patients. J Neurosurg 107 (1 Suppl):36422007

10

Asher MLai SMBurton DManna BCooper A: Safety and efficacy of Isola instrumentation and arthrodesis for adolescent idiopathic scoliosis: two- to 12-year follow-up. Spine (Phila Pa 1976) 29:201320232004

11

Aydingoz OBilsel NBotanlioglu HBozdag ESunbuloglu EKesmezacar H: Effect of decortication on laminar strength during sublaminar wiring: an experimental study. J Spinal Disord Tech 17:4985042004

12

Bailey DK: The normal cervical spine in infants and children. Radiology 59:7127191952

13

Bambakidis NCFeiz-Erfan IHorn EMGonzalez LFBaek SYüksel KZ: Biomechanical comparison of occipitoatlantal screw fixation techniques. J Neurosurg Spine 8:1431522008

14

Belmont PJ JrKlemme WRDhawan APolly DW Jr: In vivo accuracy of thoracic pedicle screws. Spine (Phila Pa 1976) 26:234023462001

15

Ben-David B: Spinal cord monitoring. Orthop Clin North Am 19:4274481988

16

Bernstein RMHall JE: Solid rod short segment anterior fusion in thoracolumbar scoliosis. J Pediatr Orthop B 7:1241311998

17

Bess SAkbarnia BAThompson GHSponseller PDShah SAEl Sebaie H: Complications of growing-rod treatment for early-onset scoliosis: analysis of one hundred and forty patients. J Bone Joint Surg Am 92:253325432010

18

Betz RRKim JD’Andrea LPMulcahey MJBalsara RKClements DH: An innovative technique of vertebral body stapling for the treatment of patients with adolescent idiopathic scoliosis: a feasibility, safety, and utility study. Spine (Phila Pa 1976) 28:S255S2652003

19

Betz RRRanade ASamdani AFChafetz RD’Andrea LPGaughan JP: Vertebral body stapling: a fusionless treatment option for a growing child with moderate idiopathic scoliosis. Spine (Phila Pa 1976) 35:1691762010

20

Boos NWebb JK: Pedicle screw fixation in spinal disorders: a European view. Eur Spine J 6:2181997

21

Borne GMBedou GLPinaudeau M: Treatment of pedicular fractures of the axis. A clinical study and screw fixation technique. J Neurosurg 60:88931984

22

Boucher HH: A method of spinal fusion. J Bone Joint Surg Br 41-B:2482591959

23

Braun JTHoffman MAkyuz EOgilvie JWBrodke DSBachus KN: Mechanical modulation of vertebral growth in the fusionless treatment of progressive scoliosis in an experimental model. Spine (Phila Pa 1976) 31:131413202006

24

Brenner DElliston CHall EBerdon W: Estimated risks of radiation-induced fatal cancer from pediatric CT. AJR Am J Roentgenol 176:2892962001

25

Brockmeyer DLYork JEApfelbaum RI: Anatomical suitability of C1-2 transarticular screw placement in pediatric patients. J Neurosurg 92 (1 Suppl):7112000

26

Burton DCAsher MALai SM: Scoliosis correction maintenance in skeletally immature patients with idiopathic scoliosis. Is anterior fusion really necessary? Spine (Phila Pa 1976) 25:61682000

27

Campbell RM Jr: VEPTR: past experience and the future of VEPTR principles. Eur Spine J 22 (Suppl 2):S106S1172013

28

Capen DAGarland DEWaters RL: Surgical stabilization of the cervical spine. A comparative analysis of anterior and posterior spine fusions. Clin Orthop Relat Res (196):2292371985

29

Carlioz HOuaknine M: [Neurologic complications of surgery of the spine in children.] Chirurgie 120:26301994–1995 (Fr)

30

Casey ATHayward RDHarkness WFCrockard HA: The use of autologous skull bone grafts for posterior fusion of the upper cervical spine in children. Spine (Phila Pa 1976) 20:221722201995

31

Chadduck WMBoop FA: Use of full-thickness calvarial bone grafts for cervical spinal fusions in pediatric patients. Pediatr Neurosurg 20:1071121994

32

Chamoun RBRelyea KMJohnson KKWhitehead WECurry DJLuerssen TG: Use of axial and subaxial translaminar screw fixation in the management of upper cervical spinal instability in a series of 7 children. Neurosurgery 64:7347392009

33

Chern JJChamoun RBWhitehead WECurry DJLuerssen TGJea A: Computed tomography morphometric analysis for axial and subaxial translaminar screw placement in the pediatric cervical spine. J Neurosurg Pediatr 3:1211282009

34

Chern JJRelyea KJea A: Instrumentation and stabilization of the pediatric spine: technical nuances and age-specific considerations in Quinones-Hinojosa A (ed): Schmidek & Sweet: Operative Neurosurgical Techniques: Indications Methods and Results ed 6. Philadelphia: Elsevier Saunders2012 Vol 1 pp 759767

35

Coe JDWarden KESutterlin CE IIIMcAfee PC: Biomechanical evaluation of cervical spinal stabilization methods in a human cadaveric model. Spine (Phila Pa 1976) 14:112211311989

36

Deen HGBirch BDWharen REReimer R: Lateral mass screw-rod fixation of the cervical spine: a prospective clinical series with 1-year follow-up. Spine J 3:4894952003

37

Desai SKBrayton AChua VBLuerssen TGJea A: The lasting legacy of Paul Randall Harrington to pediatric spine surgery: historical vignette. J Neurosurg Spine 18:1701772013

38

Desai SKSayama CVener DBrayton ABriceño VLuerssen TG: The feasibility and safety of using sublaminar polyester bands in hybrid spinal constructs in children and transitional adults for neuromuscular scoliosis. J Neurosurg Pediatr 15:3283372015

39

Dickman CASonntag VK: Posterior C1-C2 transarticular screw fixation for atlantoaxial arthrodesis. Neurosurgery 43:2752811998

40

DiFiore JWWilson JM: Lung development. Semin Pediatr Surg 3:2212321994

41

Dohin BDubousset JF: Prevention of the crankshaft phenomenon with anterior spinal epiphysiodesis in surgical treatment of severe scoliosis of the younger patient. Eur Spine J 3:1651681994

42

Du JYAichmair AKueper JWright TLebl DR: Biomechanical analysis of screw constructs for atlantoaxial fixation in cadavers: a systematic review and meta-analysis. J Neurosurg Spine 22:1511612015

43

Dubousset JHerring JAShufflebarger H: The crankshaft phenomenon. J Pediatr Orthop 9:5415501989

44

Dvorak MFKwon BKFisher CGEiserloh HL IIIBoyd MWing PC: Effectiveness of titanium mesh cylindrical cages in anterior column reconstruction after thoracic and lumbar vertebral body resection. Spine (Phila Pa 1976) 28:9029082003

45

Farey IDNadkarni SSmith N: Modified Gallie technique versus transarticular screw fixation in C1-C2 fusion. Clin Orthop Relat Res (359):1261351999

46

Faure AMonteiro RHamel ORaoul SSzapiro JAlcheikh M: Inverted-hook occipital clamp system in occipitocervical fixation. Technical note. J Neurosurg 97 (1 Suppl):1351412002

47

Fehlings MGCooper PRErrico TJ: Posterior plates in the management of cervical instability: long-term results in 44 patients. J Neurosurg 81:3413491994

48

Garber STBrockmeyer DL: Management of subaxial cervical instability in very young or small-for-age children using a static single-screw anterior cervical plate: indications, results, and long-term follow-up. J Neurosurg Spine 24:8928962016

49

Ghiselli GWang JCBhatia NNHsu WKDawson EG: Adjacent segment degeneration in the lumbar spine. J Bone Joint Surg Am 86-A:1497–15032004

50

Gill KPaschal SCorin JAshman RBucholz RW: Posterior plating of the cervical spine. A biomechanical comparison of different posterior fusion techniques. Spine (Phila Pa 1976) 13:8138161988

51

Girardi FPBoachie-Adjei ORawlins BA: Safety of sublaminar wires with Isola instrumentation for the treatment of idiopathic scoliosis. Spine (Phila Pa 1976) 25:6916952000

52

Gluf WMBrockmeyer DL: Atlantoaxial transarticular screw fixation: a review of surgical indications, fusion rate, complications, and lessons learned in 67 pediatric patients. J Neurosurg Spine 2:1641692005

53

Goel ALaheri V: Plate and screw fixation for atlanto-axial subluxation. Acta Neurochir (Wien) 129:47531994

54

Goldstein HENeira JABanu MAldana PRBraga BPBrockmeyer DL: Growth and alignment of the pediatric subaxial cervical spine following rigid instrumentation and fusion: a multicenter study of the Pediatric Craniocervical Society. J Neurosurg Pediatr 22:81882018

55

Grob DDvorak JPanjabi MMAntinnes JA: The role of plate and screw fixation in occipitocervical fusion in rheumatoid arthritis. Spine (Phila Pa 1976) 19:254525511994

56

Haher TRYeung AWCaruso SAMerola AAShin TZipnick RI: Occipital screw pullout strength. A biomechanical investigation of occipital morphology. Spine (Phila Pa 1976) 24:591999

57

Harms JMelcher RP: Posterior C1-C2 fusion with polyaxial screw and rod fixation. Spine (Phila Pa 1976) 26:246724712001

58

Harrington PR: The history and development of Harrington instrumentation. Clin Orthop Relat Res (93):1101121973

59

Harrington PR: Treatment of scoliosis. Correction and internal fixation by spine instrumentation. J Bone Joint Surg Am 44-A:5916101962

60

Hedequist DJHall JEEmans JB: The safety and efficacy of spinal instrumentation in children with congenital spine deformities. Spine (Phila Pa 1976) 29:208120872004

61

Hefti FLMcMaster MJ: The effect of the adolescent growth spurt on early posterior spinal fusion in infantile and juvenile idiopathic scoliosis. J Bone Joint Surg Br 65:2472541983

62

Herring JAWenger DR: Segmental spinal instrumentation: a preliminary report of 40 consecutive cases. Spine (Phila Pa 1976) 7:2852981982

63

Heywood AWLearmonth IDThomas M: Internal fixation for occipito-cervical fusion. J Bone Joint Surg Br 70:7087111988

64

Holland CMKebriaei MAWrubel DM: Posterior cervical spinal fusion in a 3-week-old infant with a severe subaxial distraction injury. J Neurosurg Pediatr 17:3533562016

65

Howington JUKruse JJAwasthi D: Surgical anatomy of the C-2 pedicle. J Neurosurg 95 (1 Suppl):88922001

66

Hwang SWGressot LVRangel-Castilla LWhitehead WECurry DJBollo RJ: Outcomes of instrumented fusion in the pediatric cervical spine. J Neurosurg Spine 17:3974092012

67

Jain AKebaish KMSponseller PD: Factors associated with use of bone morphogenetic protein during pediatric spinal fusion surgery: an analysis of 4817 patients. J Bone Joint Surg Am 95:126512702013

68

Jea ATaylor MDDirks PBKulkarni AVRutka JTDrake JM: Incorporation of C-1 lateral mass screws in occipitocervical and atlantoaxial fusions for children 8 years of age or younger. Technical note. J Neurosurg 107 (2 Suppl):1781832007

69

Jeanneret BMagerl F: Primary posterior fusion C1/2 in odontoid fractures: indications, technique, and results of transarticular screw fixation. J Spinal Disord 5:4644751992

70

Jenks MCraig JHiggins JWillits IBarata TWood H: The MAGEC system for spinal lengthening in children with scoliosis: a NICE medical technology guidance. Appl Health Econ Health Policy 12:5875992014

71

Johnson KTAl-Holou WNAnderson RCWilson TJKarnati TIbrahim M: Morphometric analysis of the developing pediatric cervical spine. J Neurosurg Pediatr 18:3773892016

72

Johnston CE IIHappel LT JrNorris RBurke SWKing AGRoberts JM: Delayed paraplegia complicating sublaminar segmental spinal instrumentation. J Bone Joint Surg Am 68:5565631986

73

Kamimura MEbara SItoh HTateiwa YKinoshita TTakaoka K: Accurate pedicle screw insertion under the control of a computer-assisted image guiding system: laboratory test and clinical study. J Orthop Sci 4:1972061999

74

Kennedy BCD’Amico RSYoungerman BEMcDowell MMHooten KGCouture D: Long-term growth and alignment after occipitocervical and atlantoaxial fusion with rigid internal fixation in young children. J Neurosurg Pediatr 17:941022016

75

Kleinerman RA: Cancer risks following diagnostic and therapeutic radiation exposure in children. Pediatr Radiol 36 (Suppl 2):1211252006

76

Klimo P JrAstur NGabrick KWarner WC JrMuhlbauer MS: Occipitocervical fusion using a contoured rod and wire construct in children: a reappraisal of a vintage technique. J Neurosurg Pediatr 11:1601692013

77

Kou ITakahashi YJohnson TATakahashi AGuo LDai J: Genetic variants in GPR126 are associated with adolescent idiopathic scoliosis. Nat Genet 45:6766792013

78

Krag MHBeynnon BDPope MHFrymoyer JWHaugh LDWeaver DL: An internal fixator for posterior application to short segments of the thoracic, lumbar, or lumbosacral spine. Design and testing. Clin Orthop Relat Res (203):75981986

79

Kurtz SMDevine JN: PEEK biomaterials in trauma, orthopedic, and spinal implants. Biomaterials 28:484548692007

80

Kwan KYHAlanay AYazici MDemirkiran GHelenius INnadi C: Unplanned reoperations in magnetically controlled growing rod surgery for early onset scoliosis with a minimum of two-year follow-up. Spine (Phila Pa 1976) 42:E1410E14142017

81

Lapinksy ASRichards BS: Preventing the crankshaft phenomenon by combining anterior fusion with posterior instrumentation. Does it work? Spine (Phila Pa 1976) 20:139213981995

82

Larson ANPolly DW JrGuidera KJMielke CHSantos ERLedonio CG: The accuracy of navigation and 3D image-guided placement for the placement of pedicle screws in congenital spine deformity. J Pediatr Orthop 32:e23e292012

83

Larson ANSantos ERPolly DW JrLedonio CGSembrano JNMielke CH: Pediatric pedicle screw placement using intraoperative computed tomography and 3-dimensional image-guided navigation. Spine (Phila Pa 1976) 37:E188E1942012

84

Lee CSNachemson AL: The crankshaft phenomenon after posterior Harrington fusion in skeletally immature patients with thoracic or thoracolumbar idiopathic scoliosis followed to maturity. Spine (Phila Pa 1976) 22:58671997

85

Lee SMSuk SIChung ER: Direct vertebral rotation: a new technique of three-dimensional deformity correction with segmental pedicle screw fixation in adolescent idiopathic scoliosis. Spine (Phila Pa 1976) 29:3433492004

86

Lenke LGBridwell KH: Mesh cages in idiopathic scoliosis in adolescents. Clin Orthop Relat Res (394):981082002

87

Leonard JRWright NM: Pediatric atlantoaxial fixation with bilateral, crossing C-2 translaminar screws. Technical note. J Neurosurg 104 (1 Suppl):59632006

88

Li WLi YZhang LGuo HTian DLi Y: AKAP2 identified as a novel gene mutated in a Chinese family with adolescent idiopathic scoliosis. J Med Genet 53:4884932016

89

Liang JLi SXu DZhuang QRen ZChen X: Risk factors for predicting complications associated with growing rod surgery for early-onset scoliosis. Clin Neurol Neurosurg 136:15192015

90

Liljenqvist ULepsien UHackenberg LNiemeyer THalm H: Comparative analysis of pedicle screw and hook instrumentation in posterior correction and fusion of idiopathic thoracic scoliosis. Eur Spine J 11:3363432002

91

Liljenqvist URHalm HFLink TM: Pedicle screw instrumentation of the thoracic spine in idiopathic scoliosis. Spine (Phila Pa 1976) 22:223922451997

92

Lonstein JEWinter RBMoe JHBradford DSChou SNPinto WC: Neurologic deficits secondary to spinal deformity. A review of the literature and report of 43 cases. Spine (Phila Pa 1976) 5:3313551980

93

Luque ER: Segmental spinal instrumentation for correction of scoliosis. Clin Orthop Relat Res (163):1921981982

94

Madawi AACasey ATSolanki GATuite GVeres RCrockard HA: Radiological and anatomical evaluation of the atlantoaxial transarticular screw fixation technique. J Neurosurg 86:9619681997

95

Majd MECastro FP JrHolt RT: Anterior fusion for idiopathic scoliosis. Spine (Phila Pa 1976) 25:6967022000

96

Marchesi DGMichel MLowery GLAebi M: Anterior transpedicular fixation of the lower thoracic and lumbar spine. Experimental verification using a new direction finder. Spine (Phila Pa 1976) 18:4614651993

97

Martinez-Del-Campo ETurner JDRangel-Castilla LSoriano-Baron HKalb STheodore N: Pediatric occipitocervical fixation: radiographic criteria, surgical technique, and clinical outcomes based on experience of a single surgeon. J Neurosurg Pediatr 18:4524622016

98

Martinez-Del-Campo ETurner JDSoriano-Baron HNewcomb AGKalb STheodore N: Pediatric occipitocervical fusion: long-term radiographic changes in curvature, growth, and alignment. J Neurosurg Pediatr 18:6446522016

99

McCarthy REMcCullough FL: Shilla growth guidance for early-onset scoliosis: results after a minimum of five years of follow-up. J Bone Joint Surg Am 97:157815842015

100

Mehlman CTAraghi ARoy DR: Hyphenated history: the Hueter-Volkmann law. Am J Orthop 26:7988001997

101

Mente PLStokes IASpence HAronsson DD: Progression of vertebral wedging in an asymmetrically loaded rat tail model. Spine (Phila Pa 1976) 22:129212961997

102

Merloz PTonetti JPittet LCoulomb MLavallée STroccaz J: Computer-assisted spine surgery. Comput Aided Surg 3:2973051998

103

Montesano PXJauch EJonsson H Jr: Anatomic and biomechanical study of posterior cervical spine plate arthrodesis: an evaluation of two different techniques of screw placement. J Spinal Disord 5:3013051992

104

Myles RTFong BEsses SIHipp JA: Radiographic verification of pedicle screw pilot hole placement using Kirshner wires versus beaded wires. Spine (Phila Pa 1976) 24:4764801999

105

Nachlas IWBorden JN: The cure of experimental scoliosis by directed growth control. J Bone Joint Surg Am 33-A:24341951

106

Nadim YLu JSabry FFEbraheim N: Occipital screws in occipitocervical fusion and their relation to the venous sinuses: an anatomic and radiographic study. Orthopedics 23:7177192000

107

Newton POFarnsworth CLFaro FDMahar ATOdell TRMohamad F: Spinal growth modulation with an anterolateral flexible tether in an immature bovine model: disc health and motion preservation. Spine (Phila Pa 1976) 33:7247332008

108

Newton POFricka KBLee SSFarnsworth CLCox TGMahar AT: Asymmetrical flexible tethering of spine growth in an immature bovine model. Spine (Phila Pa 1976) 27:6896932002

109

Ni BGuo XXie NLu XYuan WLi S: Bilateral atlantoaxial transarticular screws and atlas laminar hooks fixation for pediatric atlantoaxial instability. Spine (Phila Pa 1976) 35:E1367E13722010

110

Odent TBou Ghosn RDusabe JPZerah MGlorion C: Internal fixation with occipital hooks construct for occipito-cervical arthrodesis. Results in 14 young or small children. Eur Spine J 24:941002015

111

Ogura YKou IMiura STakahashi AXu LTakeda K: A functional SNP in BNC2 is associated with adolescent idiopathic scoliosis. Am J Hum Genet 97:3373422015