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.
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.
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.
Meng Huang, David D. Gonda, Valentina Briceño, Sandi K. Lam, Thomas G. Luerssen and Andrew Jea
Upper airway obstruction resulting from overflexion of the craniocervical junction after occipitocervical fusion is a rare but potentially life-threatening complication and is associated with morbidity. The authors retrospectively reviewed the medical records and diagnostic images of 2 pediatrie patients who underwent occipitocervical fusion by the Neuro-Spine Program at Texas Children’s Hospital and experienced dyspnea and/or dysphagia from new upper airway obstruction in the postoperative period. Patient demographics, operative data, and preoperative and postoperative occiput-C2 angles were recorded. A review of the literature for similar complications after occipitocervical fusion was performed. A total of 13 cases of prolonged upper airway obstruction after occipitocervical fusion were analyzed. Most of these cases involved adults with rheumatoid arthritis. To the best of the authors’ knowledge, there have been no previous reports of prolonged upper airway obstruction in children after an occipitocervical fusion. Fixation of the neck in increased flexion (−18° to −5°) was a common finding among these adult and pediatrie cases. The authors’ cases involved children with micrognathia and comparatively large tongues, which may predispose the oropharynx to obstruction with even the slightest amount of increased flexion. Close attention to a satisfactory fixation angle (occiput-C2 angle) is necessary to avoid airway obstruction after an occipitocervical fusion. Children with micrognathia are particularly sensitive to changes in flexion at the craniocervical junction after occipitocervical fixation.
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.
David D. Gonda, Jared Fridley, Sheila L. Ryan, Valentina Briceño, Sandi K. Lam, MD MBA, Thomas G. Luerssen and Andrew Jea
Low-molecular-weight heparins (LMWHs), mainly enoxaparin, offer several advantages over standard anticoagulation therapies such as unfractionated heparin and warfarin, including predictable pharmacokinetics, minimal monitoring, and subcutaneous administration. The purpose of this study was to determine the safety and efficacy of LMWHs in pediatric neurosurgical patients.
A retrospective study was performed with patients 18 years old or younger who were admitted to the Pediatric Neurosurgery Service at Texas Children's Hospital and treated with LMWH for either therapeutic or prophylactic purposes between March 1, 2011, and December 30, 2013. Demographic and clinical features and outcomes were recorded.
LMWH was administered for treatment of venous thromboembolic events (VTEs) in 17 children and for prophylaxis in 24 children. Clinical resolution of VTEs occurred in 100% (17 of 17) of patients receiving therapeutic doses of LMWH. No patient receiving prophylactic doses of LMWH developed a new VTE. Major or minor bleeding complications occurred in 18% (3 of 17 children) and 4% (1 of 24 children) of those receiving therapeutic and prophylactic doses, respectively. All 4 patients who experienced hemorrhagic complications had other bleeding risk factors—i.e., coagulopathies and antiplatelet medications.
LMWH seems to be safe and efficacious for both management and prophylaxis of VTEs in pediatric neurosurgery. However, pediatric practitioners should be aware of higher risk for bleeding complications with increasing doses of LMWH, especially in patients with preexisting bleeding disorders or concurrent use of antiplatelet agents.
John R. W. Kestle
Caroline Hadley, Sandi K. Lam, Valentina Briceño, Thomas G. Luerssen and Andrew Jea
Currently there is no standardized tool for assessment of neurosurgical resident performance in the operating room. In light of enhanced requirements issued by the Accreditation Council for Graduate Medical Education’s Milestone Project and the Matrix Curriculum Project from the Society of Neurological Surgeons, the implementation of such a tool seems essential for objective evaluation of resident competence. Beyond compliance with governing body guidelines, objective assessment tools may be useful to direct early intervention for trainees performing below the level of their peers so that they may be given more hands-on teaching, while strong residents can be encouraged by faculty members to progress to conducting operations more independently with passive supervision. The aims of this study were to implement a validated assessment tool for evaluation of operative skills in pediatric neurosurgery and determine its feasibility and reliability.
All neurosurgery residents completing their pediatric rotation over a 6-month period from January 1, 2014, to June 30, 2014, at the authors’ institution were enrolled in this study. For each procedure, residents were evaluated by means of a form, with one copy being completed by the resident and a separate copy being completed by the attending surgeon. The evaluation form was based on the validated Objective Structured Assessment of Technical Skills for Surgery (OSATS) and used a 5-point Likert-type scale with 7 categories: respect for tissue; time and motion; instrument handling; knowledge of instruments; flow of operation; use of assistants; and knowledge of specific procedure. Data were then stratified by faculty versus resident (self-) assessment; postgraduate year level; and difficulty of procedure. Descriptive statistics (means and SDs) were calculated, and the results were compared using the Wilcoxon signed-rank test and Student t-test. A p value < 0.05 was considered statistically significant.
Six faculty members, 1 fellow, and 8 residents completed evaluations for 299 procedures, including 32 ventriculoperitoneal (VP) shunt revisions, 23 VP shunt placements, 19 endoscopic third ventriculostomies, and 18 craniotomies for tumor resection. There was no significant difference between faculty and resident self-assessment scores overall or in any of the 7 domains scores for each of the involved residents. On self-assessment, senior residents scored themselves significantly higher (p < 0.02) than junior residents overall and in all domains except for “time and motion.” Faculty members scored senior residents significantly higher than junior residents only for the “knowledge of instruments” domain (p = 0.05). When procedure difficulty was considered, senior residents’ scores from faculty members were significantly higher (p = 0.04) than the scores given to junior residents for expert procedures only. Senior residents’ self-evaluation scores were significantly higher than those of junior residents for both expert (p = 0.03) and novice (p = 0.006) procedures.
OSATS is a feasible and reliable assessment tool for the comprehensive evaluation of neurosurgery resident performance in the operating room. The authors plan to use this tool to assess resident operative skill development and to improve direct resident feedback.