Mitchell Campbell

Adverse Effects Associated With High-dose Recombinant Human Bone Morphogenetic Protein-2 Use in Anterior Cervical Spine Fusion

Study Design. A retrospective review of patients who underwent an anterior cervical fusion using recombinant human bone morphogenetic protein (rhBMP)-2 with an absorbable collagen sponge (INFUSE®; Medtronic Sofamor Danek, Minneapolis, MN). Objective. To ascertain the complication rate after the use of high-dose INFUSE® in anterior cervical fusions. Summary of Background Data. The rhBMP-2 has been primarily investigated in lumbar spine fusions, where it has significantly enhanced the fusion rate and decreased the length of surgery, blood loss, and hospital stay. Methods. We present 151 patients who underwent either an anterior cervical discectomy and fusion (n = 138) or anterior cervical vertebrectomy and fusion (n = 13) augmented with high-dose INFUSE® between July 2003 and March 2004. The rhBMP-2 (up to 2.1 mg/level) was used in the anterior cervical discectomy and fusions. Results. A total of 35 (23.2%) patients had complications after the use of high-dose INFUSE® in the cervical spine. There were 15 patients diagnosed with a hematoma, including 11 on postoperative day 4 or 5, of whom 8 were surgically evacuated. Thirteen individuals had either a prolonged hospital stay (>48 hours) or hospital readmission because of swallowing/breathing difficulties or dramatic swelling without hematoma. Conclusions. A significant rate of complications resulted after the use of a high dose of INFUSE® in anterior cervical fusions. We hypothesize that in the cervical area, the putative inflammatory effect that contributes to the effectiveness of INFUSE® in inducing fusion may spread to adjacent critical structures and lead to increased postoperative morbidity. A thorough investigation is warranted to determine the optimal dose of rhBMP-2 that will promote cervical fusion and minimize complications.

Treatment of Pyogenic Vertebral Osteomyelitis With Anterior Debridement and Fusion Followed by Delayed Posterior Spinal Fusion

Study Design. Case series. Objectives. The results of surgical treatment of osteomyelitis with anterior debridement and fusion followed by delayed posterior stabilization and fusion are presented. Methods. Forty-two patients with vertebral osteomyelitis are presented. There were 5 cervical, 12 thoracic, 1 thoracolumbar, 19 lumbar, and 5 lumbosacral lesions. The most frequently identified organism was Staphylococcus aureus. Most patients had significant comorbidities, including diabetes, or were immunocompromised. Ninety percent had elevated erythrocyte sedimentation rates and C-reactive proteins, while white blood cell counts were less reliably elevated. Imaging studies included radiographs, CT scans, and MRIs. All patients were treated with anterior debridement and strut grafting followed by 14.4 days of intravenous antibiotics and delayed instrumented posterior fusions and received 6 weeks of intravenous antibiotics after surgery. Results. All patients had resolution of their infections with no recurrence. There were two deaths. Neurologic deficits resolved in all patients. The diagnosis of pyogenic vertebral osteomyelitis is frequently delayed and presents a significant surgical challenge. The indications for surgical debridement were neurologic compromise, failed medical treatment, soft tissue extension, extensive vertebral body and disc space destruction, and progressive deformity. Many of these patients were severely ill at presentation and required urgent treatment. Anterior debridement and fusion followed by intravenous antibiotics allows for restoration of anterior column support and control of the infection before posterior instrumentation and fusion. Conclusion. This study demonstrates that anterior surgical debridement with fusion, followed by a period of intravenous antibiotics and delayed instrumented posterior fusion, is highly effective in the treatment of pyogenic osteomyelitis that has failed medical management.

Pediatric Spine Fractures: A Review of 137 Hospital Admissions

Objective: The anatomy and biomechanics of the growing spine produce failure patterns different from those in adults. Spinal injury in the pediatric patient is a concern as prevention of further neurologic damage and deformity and the good potential for recovery make timely identification and appropriate treatment of such injury critical. A retrospective clinical case series was conducted to present data from a large series of pediatric patients with spine injuries from a single regional trauma center. Methods: One hundred thirty-seven children with spine injuries were seen over 10 years and were divided into three age groups: 0-9, 10-14, and 15-17 years. Analysis of variance and χ2 were used to analyze differences between groups. Results: There were 36 patients aged 0-9, 49 aged 10-14, and 52 aged 15-17. Spine injury incidence increased with age. Motor vehicular accidents were the most common cause in this series. There were 36% cervical, 34% thoracic, 29% lumbar, 34% multilevel contiguous, and 7% multilevel noncontiguous involvement. Nineteen percent had spinal cord injury. Thirteen of 21 complete neurologic injuries and all 3 incomplete injuries improved. Cord injury was more common in the 0-9 age group. Four of five patients with spinal cord injury without radiographic abnormality (SCIWORA) were in the 0-9 age group and had complete neurologic injuries. Young children with cervical injuries were more likely to die than older children. Fifty-three percent had associated injuries. Eighteen percent underwent decompression, fusion, and instrumentation. Two patients developed scoliosis. The complication rate in surgical patients was higher than in patients treated nonsurgically and in polytrauma patients. This may be related to the severity of the initial injury. Our results suggest age-related patterns of injury that differ from previous work. The incidence of cord injury is 20% with higher frequencies in the young child. Potential for neurologic recovery is good. Young children have a higher risk for death than older children. There was no predominance of cervical injuries in the young child. The incidence of SCIWORA was low. Higher complication rates were seen in polytrauma and surgical patients.

Initial Fusion Rates With Recombinant Human Bone Morphogenetic Protein-2/compression Resistant Matrix and a Hydroxyapatite and Tricalcium Phosphate/collagen Carrier in Posterolateral Spinal Fusion

Study Design. Prospective, randomized, unblinded study of iliac crest bone graft (ICBG) versus recombinant human bone morphogenetic protein-2/compression resistant matrix (rhBMP-2/CRM)in a posterolateral instrumented fusion procedure. Objectives. Document initial radiographic characteristics, based on computed tomography, with rhBMP-2/CRM for posterolateral fusion at 6 and 12-month intervals. Summary of Background Data. As the acceptance of INFUSE bone graft as an ICBG replacement becomes more widespread, surgeons have begun to study applications for rhBMP-2 in posterior spinal fusion. Preclinical studies have examined variables including carrier composition, rhBMP-2 concentration, and rhBMP-2 dose. Pilot studies have been performed with encouraging initial results. Methods. Patients with single level lumbar degenerative disease were enrolled in a randomized study of ICBG versus rhBMP-2/CRM in a posterolateral instrumented fusion procedure. Computed tomography scans at 6 and 12 months were graded as demonstrating no fusion (grade 1), partial or limited unilateral fusion (grade 2), partial or limited bilateral fusion (grade 3), solid unilateral fusion (grade 4), or solid bilateral fusion (grade 5). Results. At our institution, 74 patients (38 rhBMP-2/CRM, 36 ICBG) reached minimum 1-year follow-up and were included in this analysis. Mean fusion grade (scale1–5) at 6 months after surgery was 4.35 in the rhBMP-2/CRM group versus 3.09 in the ICBG group (P < 0.0001). At 1 year after surgery mean fusion grade was 4.62 in the rhBMP-2/CRM group versus 3.77 in the ICBG group (P < 0.0023). Conclusions. These early results are encouraging and suggest a more rapid incorporation and development of the fusion mass with rhBMP-2/CRM than iliac crest autograft in a single level posterior instrumented fusion.

RhBMP-2 Versus Iliac Crest Bone Graft for Lumbar Spine Fusion : A Randomized, Controlled Trial in Patients Over Sixty Years of Age

Study Design. Prospective randomized controlled trial of rhBMP-2/ACS (Infuse bone graft) versus iliac crest bone graft (ICBG) for lumbar spine fusion in patients over 60 years of age. Objective. To report on clinical, radiographic, and economic outcomes, at 2-year follow-up, in patients treated by posterolateral lumbar fusion with rhBMP-2/ACS versus ICBG. Summary of Background Data. RhBMP-2/ACS is widely used “off-label” for posterolateral spinal fusion. Despite encouraging initial reports, outstanding issues include the need for evidence regarding safety and efficacy in an older population; and an assessment of cost-effectiveness. Methods. Patients over 60 years old were randomized to rhBMP-2/ACS (n = 50) or ICBG (n = 52). Oswestry Disability Index, Short Form-36, and numerical rating scales for back and leg pain were determined preoperatively and at 6, 12, and 24 months postoperatively. Fusion was evaluated by fine-cut computed tomography scan 2 years postoperatively by 3 reviewers. All in-patient and subsequent out-patient event costs were recorded by a dedicated hospital coder. Results. Two-year postoperative improvement in Oswestry Disability Index averaged 15.8 in the rhBMP-2/ACS group and 13.0 in the ICBG group. Mean improvement in Short Form-36 physical component score was 6.6 in the rhBMP-2/ACS group and 7.5 in the ICBG group. There were 20 complications in the ICBG group and 8 complications in the rhBMP-2/ACS group (P = 0.014). Sixteen ICBG and 10 rhBMP-2/ACS patients required additional treatment for persistent back or leg symptoms. Two rhBMP-2/ACS patients had revision procedures, 1 for nonunion. Eight patients in the ICBG group had revision procedures, 5 for nonunion. Mean fusion grade on computed tomography scan was significantly (P = 0.030) better in the rhBMP-2/ACS (4.3) compared with the ICBG group (3.8). Mean cost of the initial admission was

RhBMP-2 Versus Iliac Crest Bone Graft for Lumbar Spine Fusion in Patients Over 60 Years of Age : A Cost-Utility Study

36,530 in the rhBMP-2/ACS group and

Perioperative complications of recombinant human bone morphogenetic protein-2 on an absorbable collagen sponge versus iliac crest bone graft for posterior cervical arthrodesis.

34,235 in the iliac crest bone graft (ICBG) group. Total cost of care over 2 years was

Are Preoperative Health-Related Quality of Life Scores Predictive of Clinical Outcomes After Lumbar Fusion?

42,574 for the ICBG group and

Correlation of spinal canal dimensions to efficacy of epidural steroid injection in spinal stenosis.

40,131 for the rhBMP-2/ACS group. Conclusion. RhBMP-2/ACS is a viable ICBG replacement in older patients in terms of safety, clinical efficacy, and cost-effectiveness.

Adverse events in patients re-exposed to bone morphogenetic protein for spine surgery.

Study Design. Randomized clinical trial. Objective. To perform a cost-utility analysis using actual cost data from a randomized clinical trial of patients over 60 years old who underwent posterolateral fusion using either rhBMP-2/ACS or iliac crest bone graft (ICBG). Summary Background Data. Bone morphogenetic protein has been shown to be an effective bone graft substitute for spine fusion. However, a clinical trial-based economic analysis of rhBMP-2/ACS compared with iliac crest bone graft has not been done. Methods. Patients over 60 years old requiring decompression and posterolateral fusion were randomized to rhBMP-2/ACS (n = 50) or ICBG (n = 52). A dedicated hospital coder and research nurse tracked each patient to determine direct costs of inpatient care and all postoperative healthcare encounters up to 2 years after surgery. Preoperative and 2-year-postoperative SF-6D utility scores for each patient were determined. A decision tree was created, which included the probability of complications, need for additional treatments and revision surgery; and the costs associated with initial surgery and treatment for complications and additional treatment for continued spine symptoms; and utility scores. Results. The mean total 2-year cost for care (excluding complication and additional spine treatment costs) was