Ben A. Strickland, Christina Sayama, Valentina Briceño, Sandi K. Lam, Thomas G. Luerssen and Andrew Jea
In a previous study, the authors reported on their experience with the use of sublaminar polyester bands as part of segmental spinal constructs. However, the risk of neurological complications with sublaminar passage of instrumentation, such as spinal cord injury, limits the use of this technique. The present study reports the novel use of subtransverse process polyester bands in posterior instrumented spinal fusions of the thoracic and lumbar spines and sacrum or ilium in 4 patients.
The authors retrospectively reviewed the demographic and procedural data of patients who had undergone posterior instrumented fusion using subtransverse process polyester bands.
Four patients, ranging in age from 11 to 22 years, underwent posterior instrumented fusion for neuromuscular scoliosis (3 patients) and thoracic hyperkyphosis (1 patient). There were 3 instances of transverse process fracture, with application and tensioning of the polyester band in 1 patient. Importantly, there was no instance of spinal cord injury with subtransverse process passage of the polyester band. The lessons learned from this technique are discussed.
This study has shown the “Eleghia” technique of passing subtransverse process bands to be a technically straightforward and neurologically safe method of spinal fixation. Pedicle screws, laminar/pedicle/transverse process hooks, and sublaminar metal wires/bands have been incorporated into posterior spinal constructs; they have been widely reported and used in the thoracic and lumbar spines and sacrum or ilium with varying success. This report demonstrates the promising results of hybrid posterior spinal constructs that include the Eleghia technique of passing subtransverse process polyester bands. This technique incorporates technical ease with minimal risk of neurological injury and biomechanical stability.
Christina Sayama, Caroline Hadley, Gina N. Monaco, Anish Sen, Alison Brayton, Valentina Briceño, Brandon H. Tran, Sheila L. Ryan, Thomas G. Luerssen, Daniel Fulkerson and Andrew Jea
The purpose of this study focusing on fusion rate was to determine the efficacy of recombinant human bone morphogenetic protein–2 (rhBMP-2) use in posterior instrumented fusions of the craniocervical junction in the pediatric population. The authors previously reported the short-term (mean follow-up 11 months) safety and efficacy of rhBMP-2 use in the pediatric age group. The present study reports on their long-term results (minimum of 12 months' follow-up) and focuses on efficacy.
The authors performed a retrospective review of 83 consecutive pediatric patients who had undergone posterior occipitocervical or atlantoaxial spine fusion at Texas Children's Hospital or Riley Children's Hospital during the period from October 2007 to October 2012. Forty-nine patients were excluded from further analysis because of death, loss to follow-up, or lack of CT evaluation of fusion at 12 or more months after surgery. Fusion was determined by postoperative CT scan at a minimum of 12 months after surgery. The fusion was graded and classified by a board-certified fellowship-trained pediatric neuroradiologist. Other factors, such as patient age, diagnosis, number of vertebral levels fused, use of allograft or autograft, dosage of bone morphogenetic protein (BMP), and use of postoperative orthosis, were recorded.
Thirty-four patients had a CT scan at least 12 months after surgery. The average age of the patients at surgery was 8 years, 1 month (range 10 months–17 years). The mean follow-up was 27.7 months (range 12–81 months). There were 37 fusion procedures in 34 patients. Solid fusion (CT Grade 4 or 4−) was achieved in 89.2% of attempts (33 of 37), while incomplete fusion or failure of fusion was seen in 10.8%. Based on logistic regression analysis, there was no significant association between solid fusion and age, sex, BMP dose, type of graft material, use of postoperative orthosis, or number of levels fused. Three of 34 patients (8.8%) required revision surgery.
Despite the large number of adult studies reporting positive effects of BMP on bone fusion, our long-term outcomes using rhBMP-2 in the pediatric population suggest that rates of fusion failure are higher than observed in contemporary adult and pediatric reports of occipitocervical and atlantoaxial spine fusions.
Christina Sayama, Matthew Willsey, Murali Chintagumpala, Alison Brayton, Valentina Briceño, Sheila L. Ryan, Thomas G. Luerssen, Steven W. Hwang and Andrew Jea
The aim of this study was to determine the safety of recombinant human bone morphogenetic protein–2 (rhBMP-2) use in posterior instrumented fusions in the pediatric population, focusing on cancer risk. In a previous study, the authors reported the short-term (mean follow-up of 11 months) safety and efficacy of rhBMP-2 in the pediatric age group. The present study reports their results with a minimum of 24 months' follow-up.
The authors retrospectively reviewed 57 consecutive cases involving pediatric patients who underwent posterior occiptocervical, cervical, thoracic, lumbar, or lumbosacral spine fusion from October 1, 2007, to June 30, 2011, at Texas Children's Hospital. Seven cases were excluded from further analysis because of loss to follow-up. Three patients died during the follow-up period and were placed in a separate cohort.
The patients' average age at the time of surgery was 11 years, 4 months (range 9 months to 20 years). The mean duration of follow-up was 48.4 months (range 24–70 months). Cancer status was determined at the most recent encounter with the patient and/or caretaker(s) in person, or in telephone follow-up. Twenty-four or more months after administration of rhBMP-2, there were no cases of new malignancy, degeneration, or metastasis of existing tumors. The cause of death of the patients who died during the study period was not related to BMP or to the development, degeneration, or metastasis of cancer.
Despite the large number of adult studies reporting increased cancer risk associated with BMP use, the authors' outcomes with rhBMP-2 in the pediatric population suggest that it is a safe adjunct to posterior spine fusions of the occipitocervical, cervical, thoracic, lumbar, and lumbosacral spine. There were no new cases of cancer, or degeneration or metastasis of existing malignancies in this series.
Sohum K. Desai, Christina Sayama, Daniel Vener, Alison Brayton, Valentina Briceño, Thomas G. Luerssen and Andrew Jea
The authors have previously reported on their early experience with sublaminar polyester bands in spine surgery. In this paper, the authors describe the use of sublaminar polyester bands in long-segment posterior instrumented spinal fusions from the upper thoracic spine to the ilium in 21 children and transitional adults with progressive neuromuscular scoliosis. Transitional adults were patients older than 18 years of age with a spinal disorder of pediatric onset, such as spina bifida. This dedicated study represents the first reported use of polyester bands in spine surgery for neuromuscular scoliosis in this patient population in the US.
The authors retrospectively reviewed the demographics and procedural data of patients who underwent posterior instrumented fusion using sublaminar polyester bands for neuromuscular scoliosis.
Twenty-one pediatric and adult transitional patients, ranging in age from 10 to 20 years (mean 14 years), underwent posterior instrumented fusion for progressive neuromuscular scoliosis. The average coronal Cobb angle measured 66° before surgery (range 37°–125°). Immediately after surgery, the mean coronal Cobb angle was 40° (range 13°–85°). At last follow-up, the average coronal Cobb angle was maintained at 42° (range 5°–112°). Regarding sagittal parameters, thoracic kyphosis was restored by 8%, and lumbar lordosis improved by 20% after surgery. Mean follow-up duration was 17 months (range 2–54 months). One patient with an aborted procedure due to loss of intraoperative evoked potentials was excluded from the analysis of radiographic outcomes. Mean surgical time was 7 hours 43 minutes (range 3 hours 59 minutes to 10 hours 23 minutes). All patients received either a 12- or 24-mg dose of recombinant human bone morphogenetic protein–2. Average estimated blood loss was 976 ml (range 300–2700 ml). Complications directly related to the use of sublaminar instrumentation included transient proprioceptive deficit (1 patient) and prolonged paraparesis (1 patient). Other complications noted in this series included disengagement of the rod from an iliac screw (1 patient), proximal junctional kyphosis (1 patient), noninfected wound drainage (2 patients), and perioperative death (1 patient). The lessons learned from these complications are discussed.
Pedicle screws, laminar/pedicle/transverse process hooks, and sublaminar metal wires have been incorporated into posterior spinal constructs and widely reported and used in the thoracic and lumbar spines and sacrum with varying success. This report demonstrates the satisfactory radiological outcomes of hybrid posterior spinal constructs in pediatric and adult neuromuscular scoliosis that include sublaminar polyester bands that promise the technical ease of passing sublaminar instrumentation with the immediate biomechanical rigidity of pedicle screws and hooks. However, the high neurological complication rate associated with this technique (2/21, or 10%) tempers the acceptable radiographic outcomes.
Christina Sayama, Sudhakar Vadivelu, Andrew Livingston, Allen Ho, Shayan A. Izaddoost, Valentina Briceño, Thomas G. Luerssen and Andrew Jea
Wound-related complications following complex posterior spine procedures in children may result in the need for serial debridements and may place spinal instrumentation at risk. In this study, the authors review their experience with the management of soft-tissue defects from spinal instrumentation in 5 high-risk pediatric patients. The use of various rotational and transpositional flaps in the management of these complicated cases is discussed, as well as their outcomes.
The authors retrospectively reviewed the medical records of 5 patients who returned to the Neuro-Spine service at Texas Children's Hospital for erosion of spinal instrumentation through the skin between September 1, 2007, and October 31, 2012. Patient demographics and clinical and operative data were recorded.
Risk factors such as young age (1 case), poor nutritional status (1 case), multiple previous surgeries (3 cases), severe neurological deficits (2 cases), and history of radiation therapy for malignancy (2 cases) were noted in the 5 patients. The paraspinous flap (4 cases) was the mainstay of the treatment. Follow-up ranged from 7.5 to 17.5 months (mean 11 ± 4.2 months). One of the patients required more than 1 procedure for revision of the wound. Cultures were positive in 2 of the 5 cases. Spinal instrumentation was removed in 3 of the 5 cases; however, in all 3 of the cases there was evidence of delayed instability that developed after the removal of spinal instrumentation.
The use of local tissue flaps is safe and efficacious for treatment of posterior wound complications due to spinal instrumentation in children. Removal of spinal instrumentation should be avoided due to the development of delayed instability. Highly vascularized tissue is used to speed healing, clear bacteria, and eliminate dead space, obviating the need to remove contaminated spinal instrumentation.
Sandi K. Lam, Christina Sayama, Dominic A. Harris, Valentina Briceño, Thomas G. Luerssen and Andrew Jea
Current national patterns as a function of patient-, hospital-, and procedure-related factors, and complication rates in the use of recombinant human bone morphogenetic protein–2 (rhBMP-2) as an adjunct to the practice of pediatric spine surgery have scarcely been investigated.
The authors conducted a cross-sectional study using data from the Healthcare Cost and Utilization Project Kids' Inpatient Database. Univariate and multivariate logistic regression were used to calculate unadjusted and adjusted odds ratios and 95% confidence intervals, and p values < 0.05 were considered to be statistically significant.
The authors identified 9538 hospitalizations in pediatric patients 20 years old or younger who had undergone spinal fusion in the US in 2009; 1541 of these admissions were associated with rhBMP-2 use. By multivariate logistic regression, the following factors were associated with rhBMP-2 use: patient age 15–20 years; length of hospital stay (adjusted odds ratio [aOR] 1.01, p = 0.017); insurance status (private [aOR 1.49, p < 0.001] compared with Medicaid); hospital type (nonchildren's hospital); region (Midwest [aOR 2.49, p = 0.008] compared with Northeast); spinal refusion (aOR 2.20, p < 0.001); spinal fusion approach/segment (anterior lumbar [aOR 1.73, p < 0.001] and occipitocervical [aOR 1.86, p = 0.013] compared with posterior lumbar); short segment length (aOR 1.42, p = 0.016) and midlength (aOR 1.44, p = 0.005) compared with long; and preoperative diagnosis (Scheuermann kyphosis [aOR 1.56, p < 0.017] and spondylolisthesis [aOR 1.93, p < 0.001]).
Use of BMP in pediatric spine procedures now comprises more than 10% of pediatric spinal fusion. Patient-related (age, insurance type, diagnosis); hospital-related (children's hospital vs general hospital, region in the US); and procedure-related (redo fusion, anterior vs posterior approach, spinal levels, number of levels fused) factors are associated with the variation in BMP use in the US.