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

JNSPG 75th Anniversary Invited Review Article

Stephen Mendenhall, Dillon Mobasser, Katherine Relyea, and Andrew Jea


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.


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.


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%).


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.

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Pneumothorax complicating “in-out-in” thoracic pedicle screw placement for kyphotic deformity correction in a child

Case report

Ashwin Viswanathan, Katherine Relyea, William E. Whitehead, Daniel J. Curry, Thomas G. Luerssen, and Andrew Jea

The authors describe a rare case of pneumothorax as a complication of thoracic pedicle screw placement in an 11-year-old girl undergoing posterior segmental instrumentation for a kyphotic deformity. Spontaneous pneumothorax after posterior fusion for adolescent idiopathic scoliosis has been reported in the orthopedic literature; however, to the best of the authors' knowledge, pneumothorax directly related to pedicle screw placement for spinal deformity has not been previously described. The authors discuss the anatomical and technical aspects leading to this complication and the lessons learned from it.

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Complications of occipital screw placement for occipitocervical fusion in children

Clinical article

Steven W. Hwang, Loyola V. Gressot, Joshua J. Chern, Katherine Relyea, and Andrew Jea


Occipitocervical stabilization in the pediatric age group remains a challenge because of the regional anatomy, poor occipital bone purchase, and, in some instances, significant thinning of the occipital bone. Multiple bicortical fixation points to the occipital bone may be required to increase construct rigidity. The authors evaluated the complications of bicortical occipital screw placement in children with occipital fusion constructs.


The records of 20 consecutive pediatric patients who had undergone occipitocervical fusion between September 1, 2007, and November 30, 2010, at Texas Children's Hospital were reviewed.


The patients consisted of 10 girls and 10 boys, ranging in age from 10 months to 16 years (mean ± SD, 7.7 ± 5.1 years). Two patients were lost to follow-up, 2 died for reasons unrelated to the surgery, and the remaining patients had at least 3 months of follow-up (mean 14 ± 11.8 months) with evaluation via dynamic radiography and CT. Four patients experienced 8 complications: 2 CSF leaks, 2 vigorous venous bleedings, worsening of quadriparesis, wound infection, radiographic pseudarthrosis, and transient dysphagia. Among 114 screws, there were 2 cases of intraoperative dural venous sinus injury and 2 cases of intraoperative CSF leakage, without clinical sequelae from these complications. Only 1 case of radiographic pseudarthrosis was identified in a patient with skeletal dysplasia and a prior failed C1–2 posterior arthrodesis. There were no difficulties with wound healing because of prominent occipital instrumentation, and there was only 1 wound infection.


Data in this report confirm that including bicortical occipital screw placement in occipitocervical constructs in children may result in a high fusion rate but at the cost of a notable complication rate.

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Vacuum-assisted en bloc resection of large convexity meningiomas

Technical note

Benjamin D. Fox, Bartley D. Mitchell, Akash J. Patel, Katherine Relyea, Shankar P. Gopinath, Claudio Tatsui, and Bruce L. Ehni

Convexity meningiomas are common tumors encountered by neurosurgeons. Retracting, grasping, and mobilizing large convexity meningiomas can be difficult and awkward as well as place unwanted forces on surrounding neurovascular structures. The authors present a safe alternative to traditional retraction and manipulation methods by using a modified bulb syringe connected to standard surgical suction to function as a vacuum retractor. This technique allows for rapid, safe, en bloc resection of large convexity meningiomas with little to no pressure on the surrounding brain. The authors present an illustrative case and describe and discuss the technique.

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Transient selective downward gaze paralysis complicating posterior fossa tumor resection in children

Report of 2 cases

Joshua J. Chern, Katherine Relyea, Jane C. Edmond, William E. Whitehead, Daniel J. Curry, Thomas G. Luerssen, and Andrew Jea

Selective downward gaze paralysis has not previously been described as a complication after posterior fossa operations in children. The authors found downgaze palsy to be a transient complication after resection of large pediatric posterior fossa midline tumors reaching the aqueduct of Sylvius. They reviewed the cases of 2 children with large posterior fossa midline tumors who underwent resection via an inferior transventricular approach. They developed a hypothetical scheme to account for downward gaze paralysis based on anatomy and insight gained from experimental studies.

The authors describe potential risk factors for developing transient selective downward gaze paralysis with the hope of making more pediatric neurosurgeons aware of this complication following removal of lesions around the mesencephalic periaqueductal gray matter. Recognition and understanding of downward gaze palsy after posterior fossa surgery should improve preoperative counseling and promote postoperative family coping.

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Transtubular microendoscopic approach for resection of a choroidal arteriovenous malformation

Technical note

Daniel K. Fahim, Katherine Relyea, Vikram V. Nayar, Benjamin D. Fox, William E. Whitehead, Daniel J. Curry, Thomas G. Luerssen, and Andrew Jea

The authors describe the novel use of a table-mounted tubular retractor system (MetRx) originally designed for minimally invasive spine surgery, in the resection of an intraventricular arteriovenous malformation (AVM) in a 12-year-old child. The tubular retractor system may have several advantages over traditional Greenberg or Leyla retractors in selected intracranial procedures. In our case, the low-profile 4 × 22–mm tube and fixed table attachment offered excellent exposure of the trigone of the lateral ventricle where the choroidal AVM was located and from which it was completely resected. Immediate postoperative cerebral angiography confirmed that the entire AVM had been resected. The patient suffered no new neurological deficits as a result of the retractor system or the exposure that it afforded. Although the good clinical results of a single case cannot be directly compared with those obtained using other open techniques of intracranial surgery in larger series, microendoscopic surgery of the brain is an alternative to the other techniques and may be recommended as a time-saving, trauma-reducing procedure with the potential to improve postoperative outcomes.

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Low-grade myofibroblastic sarcoma of the sacrum

Case report

William E. Humphries III, Krishna B. Satyan, Katherine Relyea, Eugene S. Kim, Adekunle M. Adesina, Murali Chintagumpala, and Andrew Jea

Myofibroblastic tumors are soft-tissue neoplasms arising from myofibroblasts, ubiquitous cells sharing ultrastructural features of muscular and fibroblastic cells. Vasudev and Harris described a malignant counterpart of these benign tumors in 1978. Most reported cases of myofibroblastic sarcoma have arisen in the head and neck region and the soft tissues of the extremities. To the best of the authors' knowledge, there have been only 8 previous reports on primary myofibroblastic sarcoma of the bone. The authors report a new case of this rare tumor affecting the sacrum and ilium of a 15-year-old girl and discuss the role of total sacrectomy and lumbopelvic reconstruction for treatment of this disease.