Clinical and Radiographic Outcomes of Repair of Spondylolitic Spondylolisthesis via Direct Pars Repair.

STUDY DESIGN: A retrospective chart review. OBJECTIVE: The objective of this study is to investigate whether direct pars repair achieves bone healing and symptom relief in patients with spondylolitic spondylolisthesis. SUMMARY OF BACKGROUND DATA: While most cases of spondylolysis can be managed non-operatively, a small percentage of patients require surgical intervention. The outcome of direct pars repair via a standard pedicle-screw with wiring technique is controversial in patients with lumbar spondylolitic spondylolisthesis. METHODS: Medical records of patients who had undergone an open surgical pars repair were retrospectively reviewed. Standard demographic and surgical parameters were collected. All patients underwent a primary repair of the pars with autograft or bone morphogenetic protein and instrumentation using a pedicle-screw with spinous process wiring. At 6-12 months after surgery, patient's pain symptoms and postoperative CT scans were independently reviewed to assess healing; graded as non-union, partial union, or solid union. RESULTS: There were 68 patients identified (33 male and 35 female) with an average age of 18.6 years. Mean estimated blood loss was 139 ml, and mean length of hospital stay was 3.7 days. CT evaluation revealed 35 (52%) solid unions, 21 (31%) partial unions, and 12 (18%) non-unions requiring revisions. Thirty-four (50%) patients had no postop pain, 24 (35%) had mild pain, 10 (15%) had persistent pain. The majority of patients with non-unions on CT had mild or persistent pain. Patients with no or mild pain tended to be younger than those with persistent pain (17.5 years vs 24.6 years, P=0.163). CONCLUSION: This study demonstrated a partial or complete union rate of 82% and a postoperative persistent pain rate of 15%. These figures are comparable to the previous study and this pedicle-screw with wiring technique can be worth trying before interbody fusion for spondylolytic spondylolisthesis to preserve anatomical lumbar motion.

Randomized trial of Cell Saver in 2- to 3-level lumbar instrumented posterior fusions.

OBJECTIVEThe goal of this study was to determine efficacy and cost-effectiveness of Cell Saver in 2- and 3-level lumbar decompression and fusion.METHODSPatients seen at a tertiary care spine center who were undergoing a posterior 2- or 3-level lumbar decompression and fusion were randomized to have Cell Saver used during their surgery (CS group, n = 48) or not used (No Cell Saver [NCS] group, n = 47). Data regarding preoperative and postoperative hemoglobin and hematocrit, estimated blood loss, volume of Cell Saver blood reinfused, number of units and volume of allogeneic blood transfused intraoperatively and postoperatively, complications, and costs were collected. Costs associated with Cell Saver use were calculated based on units of allogeneic blood transfusions averted.RESULTSDemographics and surgical parameters were similar in both groups. The mean estimated blood loss was similar in both groups: 612 ml in the CS group and 742 ml in the NCS group. There were 53 U of allogeneic blood transfused in 29 patients in the NCS group at a total blood product cost of $67,688; and 38 U of allogeneic blood transfused in 16 patients in the CS group at a total blood cost of $113,162, resulting in a cost of $3031 per allogeneic blood transfusion averted using Cell Saver.CONCLUSIONSCell Saver use produced lower rates of allogeneic transfusion but was found to be more expensive than using only allogeneic blood for 2- and 3-level lumbar degenerative fusions. This increased cost may be reasonable to patients who perceive that the risks associated with allogeneic transfusions are unacceptable.■ CLASSIFICATION OF EVIDENCE Type of question: therapeutic; study design: randomized controlled trial; evidence: class III.

Can the anxiety domain of EQ-5D and mental health items from SF-36 help predict outcomes after surgery for lumbar degenerative disorders?

OBJECTIVE Studies have shown that anxious or depressed patients may have poorer outcomes after lumbar fusion. These conclusions were drawn from questionnaires specifically designed to measure anxiety and depression. The objective of this study is to determine if responses to the EQ-5D anxiety/depression domain or the items used to calculate the 36-Item Short-Form Health Survey (SF-36) Mental Component Summary (MCS) can predict outcomes after lumbar fusion surgery. METHODS Patients enrolled in the National Neurosurgery Quality and Outcomes Database from a single center with 1-year follow-up were identified. The outcomes collected include the Oswestry Disability Index (ODI), EQ-5D, SF-36, and the back- and leg-pain numeric rating scales (range 0-10). Linear regression modeling was performed to predict the 1-year ODI scores using the EQ-5D anxiety/depression domain and the 14 items used to calculate SF-36 MCS. RESULTS Complete data were available for 312 (88%) of 353 eligible patients. The mean patient age was 58.5 years, 175 (56%) patients were women, and 52 patients were smokers. After controlling for other factors, the item in the SF-36 that asks "Have you felt downhearted and depressed?" is the strongest predictor of the 1-year ODI score (r(2) = 0.191; p = 0.000) and 1-year EQ-5D score (r(2) = 0.205; p = 0.000). Neither the EQ-5D anxiety/depression domain nor the diagnoses of anxiety or depression were predictors of 1-year outcomes. CONCLUSIONS Patient responses to SF-36 item "Have you felt downhearted and depressed?" account for 20% of the variability of the 1-year ODI and EQ-5D scores and can be used by clinicians to screen for anxiety or depression in patients prior to lumbar fusion surgery. Clinicians may offer psychological support to these patients preoperatively in order to improve treatment outcomes.

Surgery for blastomycosis of the spine.

Blastomycosis is a rare fungal infection that primarily produces acute lung infections but may disseminate to multiple sites, including the spine. Once vertebral involvement occurs, an untreated infection may result in vertebral body destruction and paraspinal and epidural abscess formation followed by neurologic injury and loss of structural integrity of the spine. We report the case of a 30-year-old man who had pulmonary blastomycosis (treated with oral itraconazole for 6 months) and presented with a 2-month history of mild thoracolumbar back pain and numbness and tingling in the lower extremities, but no neurologic deficits. Imaging revealed a destructive lesion of T11 with an extensive paravertebral and retropleural abscess tracking a spinal level above and below with extension into the spinal canal. The patient underwent incision and drainage, culture procurement and corpectomy of T11 with autogenous rib graft in a titanium cage, and, 1 week later, posterior fusion and instrumentation. Cultures were positive for Blastomycosis dermatitidis. Oral itraconazole was continued. Blastomycosis that disseminates to the spine may cause serious neurologic and structural complications. In most cases, long-term use of antifungal medication eradicates the infection. Should medical treatment fail, however, surgery is a useful option.

Motion segment-sparing repair of symptomatic chronic pars defects.

OBJECT: The current standard of care for symptomatic chronic spondylolysis (SP) is a one-level posterior spinal fusion for defects at L-5 or direct pars repair (motion segment sparing) for more rostral SP in younger patients and if no disc degeneration or listhesis is present. Since many patients with SP undergoing operative repair are young, a procedure with the lowest biomechanical profile is desirable, and direct pars repair is recommended. The authors here explore the limits of direct pars repair. METHODS: A retrospective review of all patients who underwent direct repair of SP between 2002 and 2009 was performed. Data were analyzed for predictors of symptom relief and radiographic fusion failure. RESULTS: Of 49 patients, only 7 required a reoperation to treat clinical symptoms, and 6 of them were female (p = 0.049). In all cases of treatment failure, the patient had bilateral L-5 SP. Patients with a slip percentage as high as 30% experienced radiographic fusion and symptom relief. Disc degeneration (measured using the Modified Pfirrmann Scale) did not predict symptom persistence or radiographic fusion failure. Patients with high-grade disc disease experienced symptom relief. The authors found no predictors of treatment failure. CONCLUSIONS: The number of patients undergoing motion segment-sparing fusions of symptomatic chronic SP can be safely increased to include patients with Grade I spondylolisthesis as well as high-grade disc disease. Female patients with bilateral L-5 SP and low lordotic angles may be better served by a posterior spinal fusion from L-5 to S-1.

A rare case of anterior thoracic myelomeningocele with scoliosis--case report and review of the literature.

BACKGROUND CONTEXT: Spinal deformities associated with spinal dysraphism are a challenging problem. Myelomeningocele has been reported in the lumbar spine. However, it is rare in the thoracic spine. PURPOSE: The purpose of the report was to heighten the awareness of the rare presentation of the myelomeningocele in the thoracic spine and the ability to correct the scoliosis without debulking the lesion. STUDY DESIGN: This is a clinical case report and literature review. METHODS: We report a 13-year-old girl presented with complaints of back pain, difficulty in breathing, and easy fatigability. On examination, she had a thoracolumbar scoliosis, weakness of the right ankle dorsiflexors, and impaired sensation over the L5 dermatome of the right lower limb. Radiographic examination revealed a 128° thoracolumbar scoliosis with congenital hemivertebra at T6-T9, block vertebrae of T4 and T5, and intrathoracic myelomeningocele. She underwent an anterior closing wedge osteotomy and posterior correction of scoliosis without removal of the sac. RESULTS: Four-year postoperative follow-up is uneventful. To date, our patient is the first patient who had scoliosis correction surgery for the rare presentation of a myelomeningocele in the thoracic spine without removal of the sac. CONCLUSIONS: To the best of our knowledge, this is the only case of anterior thoracic myelomeningocele with scoliosis in the literature who had undergone a surgical correction of the scoliosis with osteotomy without removal of the sac. Although rare, these curves are well amenable to surgical correction of scoliosis, thereby improving endurance and functional lung capacity.

Classification of congenital scoliosis and kyphosis: a new approach to the three-dimensional classification for progressive vertebral anomalies requiring operative treatment.

STUDY DESIGN: We reviewed three-dimensional (3D) computed tomography (CT) images of congenital spinal deformities and proposed a new classification based on the information obtained. OBJECTIVES: The purposes of this article were to clearly illustrate the limitations of two-dimensional classification, to summarize the clinical significance of 3D analysis of congenital vertebral anomalies, and to propose a new 3D classification of congenital vertebral anomalies. SUMMARY OF BACKGROUND DATA: The classification of congenital scoliosis or kyphosis were based on radiographic findings of plain radiograph images of congenital vertebral anomalies, it is sometimes difficult in classifying the large variety of anomalous vertebrae or severely twisted 3D curves. METHODS: Three-dimensional CT images of more than 150 patients with congenital spinal deformities were analyzed and compared with plain radiograph images. By developing the algorithm for the evaluation of malformed vertebrae in terms of numbers of abnormal vertebrae, type of formation failure, and type of segmentation failure in separate steps, we attempted to revise the classification of congenital spinal deformities. RESULTS: The images of plain radiograph cannot demonstrate the spatial relationship of each structure of the vertebrae. Three-dimensional findings in congenital-deformed vertebrae included several types of laminae and clearer definitions of each type of anomalous vertebrae. By developing an algorithm for the evaluation of congenital spinal deformity, congenital spinal deformity could be mainly classified into 4 types of congenital vertebral abnormalities: Type 1: solitary simple, Type 2: multiple simple, Type 3: complex, Type 4: segmentation failure. CONCLUSION: The large volume of information that can be obtained by evaluating 3D CT images of congenitally deformed vertebrae can be a great help in developing a strategy for surgical treatment. We need to develop a new classification of congenital scoliosis based on the perspective of 3D imaging to understand the etiology and embryology, as well as to determine an operative strategy.

Are preoperative health-related quality of life scores predictive of clinical outcomes after lumbar fusion?

STUDY DESIGN: Prospective longitudinal cohort. OBJECTIVE: This study evaluated the effect of preoperative Mental Component Summary (MCS), preoperative Physical Component Summary (PCS), preoperative Oswestry Disability Index (ODI), back pain predominance, body mass index (BMI), age, smoking status, and workers' compensation on health-related quality of life after lumbar fusion. These factors were selected as they are readily available and may influence a surgeon's decision-making process. SUMMARY OF BACKGROUND DATA: Measures of health-related quality of life are increasingly used to evaluate treatment effectiveness. However, their use as a predictive tool to determine which patients will improve has been limited. METHODS: The Short Form 36 (SF-36) and ODI were collected before surgery and two years after surgery in 489 patients undergoing lumbar fusion for degenerative disorders. Linear regression modeling was used to determine the effect of preoperative MCS, preoperative PCS, preoperative ODI, back pain predominance, BMI, age, smoking status, and workers' compensation on the change in ODI and change in SF-36 PCS two years after lumbar fusion. RESULTS: Patients with better preoperative MCS (P = 0.008) and worse preoperative ODI scores (P < 0.0001) achieved greater ODI improvement. Workers' compensation patients did significantly worse (P = 0.03). Patients with better preoperative MCS (P = 0.0004), better preoperative PCS (P = 0.0155), and worse preoperative ODI scores (P = 0.0210) achieved greater PCS improvement. Those on workers' compensation had lower changes in PCS, an effect that was nearly significant (P = 0.0644). There were no significant correlations between PCS and ODI improvement and back pain predominance, BMI, age, and smoking status. Attempts at determining threshold values for MCS, PCS, and ODI that are predictive of a patient achieving minimum clinically important difference for PCS and ODI were unsuccessful. CONCLUSION: Patients with good preoperative MCS and poor preoperative ODI scores who are not on workers' compensation are more likely to improve after lumbar fusion. Threshold values for MCS, PCS, and ODI predictive of a patient achieving minimum clinically important difference for PCS and ODI could not be determined.

RhBMP-2 versus iliac crest bone graft for lumbar spine fusion in patients over 60 years of age: a cost-utility study.

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 $34,235 in the ICBG group and $36,530 in the rhBMP-2/ACS group. For the entire group, the mean cost to treat a major complication was $10,888, the cost of revision surgery for nonunion was $46,852, and additional treatment for spine-related events was $5892. In the ICBG group, 8 patients had complications; 20 had additional interventions, 5 of whom required revision for nonunion. In the rhBMP-2/ACS group, 6 patients had complications, 10 had additional interventions, and 1 required revision for nonunion. The cost of using rhBMP-2/ACS was $39,967 with a 0.11 mean improvement in SF-6D; and for ICBG the cost was $42,286 with a mean improvement of 0.10 in SF-6D. CONCLUSION: There are more complications, increased need for additional treatment and revision surgery in patients over 60 years old receiving ICBG compared with rhBMP-2/ACS. This may account for higher costs and lower improvements in utility seen in patients receiving ICBG compared with rhBMP-2/ACS in this study population.

Lumbar fusion outcomes stratified by specific diagnostic indication.

BACKGROUND: One of the primary difficulties in evaluating the effectiveness of lumbar fusion is that, with the exception of spondylolisthesis, specific diagnostic indications for surgery are poorly defined. Diagnostic specificity beyond the symptom of low back pain or the presence of lumbar degeneration needs to be delineated such that outcomes data can be effectively translated into clinical decision making or evidence-based guidelines. PURPOSE: The purpose of this study was to report on prospectively collected clinical outcome measures, stratified by diagnosis, among a series of patients with lumbar degenerative disease whose treatment included lumbar spine fusion. STUDY DESIGN: Demographics, diagnostic categorization, and clinical outcome measures were prospectively collected by six spine surgeons at a single tertiary spine center, as part of the surgeons' standard clinical practice. PATIENT SAMPLE: Four hundred and twenty-eight patients were enrolled in the study and complete 1- and 2-year Health-Related Quality of Life (HRQOL) data were available in 327 patients whose treatment included decompression and posterolateral lumbar fusion. OUTCOME MEASURES: The Oswestry Disability Index (ODI), Short Form-36 (SF-36), numeric rating scales for back pain and leg pain. METHODS: Preoperative diagnosis was classified, in the primary surgical cases, as disc pathology, spondylolisthesis, instability, stenosis, or scoliosis. In revision cases, the diagnosis was classified as nonunion, adjacent level degeneration, or postdiscectomy revision. Patient-reported outcomes at 1 and 2 years post-op were assessed based on diagnostic stratification. Statistical evaluation of clinical outcome was performed for both mean net change in outcome scores and the percentage of patients reaching a minimum clinically important difference (MCID) threshold for each outcome measure. RESULTS: Preoperative diagnosis was spondylolisthesis (n=80), scoliosis (n=17), disc pathology (n=33), instability (n=21), stenosis (n=46), postdiscectomy revision (n=67), adjacent level degeneration (n=40), or nonunion (n=23). Evaluation of 2-year post-op HRQOL measures by diagnostic subgroup revealed the most substantial improvement in ODI score for patients with spondylolisthesis (22.7 points) and scoliosis (21.2 points). Patients with the diagnosis of disc pathology (16.2 points), postdiscectomy revision (14.0 points), instability (12.7 points), stenosis (10.6 points), and adjacent level degeneration (9.5 points) demonstrated a progressively smaller magnitude of ODI improvement. The least ODI improvement at 2 years after surgery was seen in patients with nonunion of a prior fusion (5.5 points). The percentage of patients reaching MCID for ODI at 2 years post-op ranged from 71.0% in the spondylolisthesis subgroup to 34.8% in the nonunion subgroup. The greatest SF-36 physical component score improvement at 2-year follow-up was seen in patients with disc pathology (7.9 points) and spondylolisthesis (7.7 points), followed by scoliosis (6.6 points) and stenosis (6.5 points), instability (5.6 points), postdiscectomy revision (5.3 points) nonunion (3.1 points) and adjacent level degeneration (2.5 points). No significant changes from Year 1 to Year 2 were noted in any of the subgroups. For SF-36 physical component score, percentage of patients reaching MCID ranged from 63.6% in the disc pathology subgroup to 25% in the nonunion subgroup. CONCLUSIONS: This study supports the concept that added diagnostic specificity is a critical component in building an improved evidence base for lumbar fusion surgery. The magnitude of HRQOL improvement was not equal among diagnostic subgroups. The percentage of patients reaching an MCID level of improvement was also significantly influenced by diagnostic stratification. Without diagnostic specificity for entities beyond spondylolisthesis, the absence of well-defined study populations will continue to limit our ability to move toward evidence-based decision making.

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 $36,530 in the rhBMP-2/ACS group and $34,235 in the iliac crest bone graft (ICBG) group. Total cost of care over 2 years was $42,574 for the ICBG group and $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.

Surgical management of severely displaced pediatric seat-belt fracture-dislocations of the lumbar spine associated with occlusion of the abdominal aorta and avulsion of the cauda equina: a report of two cases.

STUDY DESIGN: Case report. OBJECTIVE: To present 2 cases of fracture-dislocations of the lumbar spine associated with injury to the aorta and avulsion of the cauda equina and present recommendations regarding urgent management of these injuries. SUMMARY OF BACKGROUND DATA: The "seat-belt syndrome" was first described by Garrett and Braunstein in 1962 to describe intraabdominal visceral injuries with fractures of the lumbar spine. Although this syndrome has been described in previously, there have been no reported cases of pediatric patients with significant injury to the abdominal aorta. METHODS: We present 2 seat-belt injuries occurring within a 4 month period at a pediatric trauma center with significantly displaced lumbar fracture-dislocation, abdominal aortic occlusion, and complete neurologic injury. RESULTS: Rigid fixation of the spinal fracture dislocation in both cases was delayed since these patients were deemed to be hemodynamically unstable. Aggressive mobilization, wound care, and pulmonary toilet were possible after stabilization of the spine. Despite this, 1 patient eventually died. CONCLUSION: These cases need to be managed according to principles established in the treatment of extremity fractures with vascular and neurologic injuries. That is, early rigid fixation of the fracture to protect the vascular repair.

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

STUDY DESIGN: Case series from a single spine specialty clinic. OBJECTIVE: This study analyzed wound related or anaphylactic adverse events in patients re-exposed to rhBMP-2. SUMMARY OF BACKGROUND DATA: The use of recombinant bone morphogenetic protein (rhBMP-2) as a bone graft substitute is increasing. There is concern that re-exposing patients to rhBMP-2, might result in a hyper-inflammatory response causing wound problems or an allergic reaction. METHODS: Ninety-six patients who had at least 2 spine surgeries using rhBMP-2 (Infuse, Medtronic Sofamor Danek, Memphis, TN) were identified. Anteroposterior surgeries, surgeries for infection and trauma were excluded. Demographic and operative data were collected from review of medical records. Surgeries were classified into primary, revision same approach and revision different approach. Logistic regression was used to control for variables associated with increased risk of complications. RESULTS: During the first exposure there were 90 primary fusions and 6 revisions with 2 wound infections requiring debridements and 9 minor wound problems. During the second exposure there were 25 primary fusions, 50 same approach first revisions, 16 different approach first revisions, 1 same approach second revision and 4 different approach second revisions. There were 5 wound infections, 11 minor wound problems and no allergic reactions. There was no significant difference in the number of complications between the first and second surgeries or between patients who had a second primary surgery, a revision through the same approach or through a different approach. There were no wound problems or allergic reactions among twelve patients who had a third surgery with rhBMP-2. CONCLUSION: Multiple exposures to rhBMP-2, whether for a second primary surgery, revision through the same approach or revision through a different approach does not increase the risk of a wound infections/problems or result in clinically detectable allergic reactions.

Sagittal alignment as a risk factor for adjacent level degeneration: a case-control study.

This study examined whether sagittal alignment, preexisting adjacent level degeneration, and smoking predispose patients to adjacent segment degeneration following lumbar fusion. Fifty-one patients with adjacent segment degeneration were identified and matched with control patients based on age, sex, level, and date of index surgery. Preexisting adjacent level degeneration and sagittal alignment through the fusion and from L1-S1 were determined before and after initial surgery. Patients with adjacent segment degeneration had significantly less lordosis through the fusion and lumbar spine following their initial surgery. There was no significant difference in the amount of preexisting adjacent level degeneration and smoking between the adjacent segment degeneration and control groups. Fusion of the lumbar spine in abnormal sagittal alignment, with loss of lumbar lordosis, predisposes patients to the development of adjacent segment degeneration. Adjacent segment degeneration does not appear to be just a progression of preexisting degenerative changes at the adjacent level.

The perioperative cost of Infuse bone graft in posterolateral lumbar spine fusion.

BACKGROUND CONTEXT: There is mounting evidence supporting the efficacy of bone morphogenetic protein (BMP) for both anterior interbody and posterolateral lumbar fusion. However, the relative cost of BMP remains an important concern for physicians, hospitals, and payers. PURPOSE: The purpose of this study is to report on the perioperative costs for patients treated with rhBMP-2 as compared with an iliac crest bone graft (ICBG) supplemented with graft extenders. STUDY DESIGN/SETTING: A prospective randomized controlled trial of rhBMP-2/ACS (Infuse Bone Graft; Medtronic Sofamor Danek, Memphis, TN) versus ICBG+/-graft extender for lumbar spine fusion in patients over 60 years old. PATIENT SAMPLE: One hundred two patients over 60 years old who required a posterolateral lumbar spine fusion randomized between receiving rhBMP-2/ACS or ICBG. OUTCOME MEASURES: All health-care costs over the first 3 months after surgery. METHODS: As part of a prospective randomized trial of rhBMP-2/ACS versus ICBG+/-graft extender for lumbar spine fusion, all costs over the first 3 months after surgery were directly recorded by a dedicated coder funded by Norton Healthcare, Louisville, KY. A dedicated research nurse also followed all patients throughout their hospital stay and posthospitalization recovery to identify any adverse events or additional outpatient medical care. RESULTS: Fifty patients received rhBMP-2/ACS and 52 underwent ICBG harvest. The mean hospital cost for the index admission was $24,736 for the rhBMP-2/ACS group and $21,138 for the ICBG group. Mean inpatient physician costs were $5,082 in the rhBMP-2/ACS group and $5,316 in the ICBG group. Costs associated with posthospital rehabilitation averaged $4,906 in the rhBMP-2/ACS group versus $6,820 in the ICBG group. Total payer expenditure for the 3-month perioperative period averaged $33,860 in the rhBMP-2/ACS group and $37,227 in the ICBG group. CONCLUSIONS: The hospital carries the cost burden associated with the utilization of rhBMP-2/ACS. In contrast, the payer in a Diagnosis-Related Group (DRG) model achieves a net savings, based primarily on the decreased payment for inpatient rehabilitation, but also on decreased hospital reimbursement, physician costs, and other outpatient services.

Non-neurologic complications following surgery for adolescent idiopathic scoliosis.

BACKGROUND: The reported prevalence of non-neurologic complications following corrective surgery for adolescent idiopathic scoliosis ranges from 0% to 10%. However, most studies were retrospective evaluations of treatment techniques and did not focus solely on complications. The purpose of this study was to determine the prevalence of non-neurologic complications following surgery for adolescent idiopathic scoliosis and to identify preoperative and operative factors that can increase this risk. METHODS: The demographic data, medical and surgical histories, and prevalence of non-neurologic complications were reviewed in a prospective cohort of 702 patients who had undergone corrective surgery for adolescent idiopathic scoliosis and were consecutively enrolled in a multicenter database. RESULTS: There were 556 female and 146 male patients. The mean age at the time of surgery was 14.25 years (range, eight to eighteen years). Five hundred and twenty-three patients had only posterior spinal surgery, 105 had only anterior spinal surgery, and seventy-four had a combined anterior and posterior procedure. There was a total of 108 complications in eighty-one patients, for an overall prevalence of 15.4%. There were ten respiratory complications (1.42%), six cases of excessive bleeding (0.85%), five wound infections (0.71%), and five cases of wound hematoma, seroma, or dehiscence (0.71%). Five patients, two with an early infection and three with late failure of the implant, required a reoperation. Factors that did not correlate with an increased prevalence of complications were age, body mass index, presence of cardiac or respiratory disease, previous surgery, pulmonary function, surgical approach, number of levels fused, graft material, use of a diaphragmatic incision, Lenke curve type, or region of the major curve. Although the number of patients with renal disease was small, these patients were 7.90 times more likely to have a non-neurologic complication. Increased blood loss as well as prolonged operative and anesthesia times were associated with a higher prevalence of non-neurologic complications. CONCLUSIONS: The prevalence of non-neurologic postoperative complications following surgery for correction of adolescent idiopathic scoliosis in this study was 15.4%. The few factors noted to significantly increase the rate of complications include a history of renal disease, increased operative blood loss, prolonged posterior surgery time, and prolonged anesthesia time.

Clinical outcomes in older patients after posterolateral lumbar fusion.

BACKGROUND CONTEXT: Older patients are often advised that their age is a contraindication to lumbar fusion surgery. There is, however, limited available data to support or contradict this assertion. Although prior studies of surgical treatment for lumbar degenerative disease suggest that older patients obtain symptomatic pain relief, an evaluation of fusion outcomes based on modern Health-Related Quality of Life (HRQOL) measures is lacking. PURPOSE: The purpose of this study was to document clinical outcomes based on standardized HRQOL measures in patients over 65 years of age treated by lumbar decompression and fusion surgery. DESIGN/SETTING: This study was a retrospective review of prospectively collected patient reported outcomes data. PATIENT SAMPLE: Ninety-seven consecutive patients over 65 years of age treated by lumbar decompression and fusion between 2000 and 2004 were enrolled in a prospective health status outcomes protocol. Eighty-five patients (88%) had complete data at a minimum 2-year follow-up. OUTCOME MEASURES: Medical Outcomes Study Short Form 36v.2 (SF-36), Oswestry Disability Index (ODI), numeric rating scales (NRS) back and leg pain scores. METHODS: Patients over 65 years of age treated by lumbar fusion were evaluated based on HRQOL measures at a minimum of 2 years postoperatively. Variables including history of prior surgery and occurrence of a perioperative complication were evaluated. A comparison group of patients 50 to 64 years of age was also analyzed. RESULTS: In patients over 65 years old, mean improvement of 6.21 points in SF-36 Physical Composite Score and 5.75 points in SF-36 Mental Composite Score was observed. There was a mean 16.38-point improvement in ODI, 3.08-point improvement in back pain NRS, and 2.65-point improvement in leg pain NRS. SF-36 subscale scores showed improvement for all parameters except general health, where there was a small but statistically significant decline. There was no difference in outcomes at 2 years postoperatively based on the occurrence of a perioperative complication. Patients undergoing a primary lumbar surgical procedure had consistently better outcomes than patients undergoing a revision procedure. CONCLUSIONS: The results of this study support the efficacy of lumbar decompression and fusion in selected patients over 65 years of age. Occurrence of a perioperative complication did not adversely affect clinical outcome. Patients undergoing a revision procedure should be counseled with regard to the more limited benefits seen with revision surgery.

Posterolateral lumbar spine fusion with INFUSE bone graft.

BACKGROUND CONTEXT: INFUSE has been proven effective in conjunction with threaded cages and bone dowels for single-level anterior lumbar interbody fusion (ALIF). The published experience with posterolateral fusion, although encouraging, utilizes a significantly higher dose and concentration of recombinant human bone morphogenic protein-2 (rhBMP-2) and a different carrier than the commercially available INFUSE. PURPOSE: To present an assessment of fusion rate for posterolateral spine fusion with INFUSE Bone Graft. STUDY DESIGN/SETTING: Retrospective review of patients treated using INFUSE in posterolateral spine fusion in a single institution. PATIENT SAMPLE: 91 patients with minimum 2-year follow-up who underwent posterolateral spine fusion using INFUSE as an iliac crest bone graft (ICBG) substitute. OUTCOME MEASURES: Fusion rate based on fine-cut computed tomographic (CT) scans with sagittal and coronal reconstructions. METHODS: Fusion was performed using one large INFUSE kit (12 mg rhBMP-2, 1.5 mg/mL), which was prepared according to the manufacturer's instructions. The INFUSE sponge was wrapped around the local bone or graft extender and placed over the decorticated surfaces in the lateral gutters. Postoperative CT scans with reconstructions were reviewed by two independent orthopedic spine surgeons. CT scans of a comparison group of 35 patients who underwent primary single-level posterolateral fusion with ICBG were also reviewed. RESULTS: The overall group had a mean 4.38 CT fusion grade and a 6.6% nonunion rate. Primary one-level fusion cases (n=48) had a mean 4.42 fusion grade a 4.2% nonunion rate. Primary multilevel fusions (n=27) had a mean 4.65 CT grade and no nonunions detected. Assessment of the 35 primary one-level ICBG control cases demonstrated a mean CT grade of 4.35 and a nonunion rate of 11.4%. In the 16 cases of revision for prior nonunion, mean CT grade was 3.81 and 4 subjects had nonunions. Additional subgroup analysis showed that smokers (n=14) had a mean 4.32 CT grade with no nonunions. Men had a mean 4.04 CT grade and an 11.1% nonunion rate compared with a mean 4.61 CT grade and 3.6% nonunion rate in women. This difference was statistically significant (p=.036). No significant differences in fusion rate were observed based upon the specific graft extender used (p=.200). CONCLUSIONS: Posterolateral spine fusion involves a more difficult healing environment with a limited surface for healing, a gap between transverse processes and the milieu of distractive forces. Historically, only ICBG has been able to overcome these challenges and reliably generate a successful posterolateral lumbar spine fusion. In contrast to prior studies, clinically available INFUSE delivers only 12 mg rhBMP-2 at a concentration of 1.5 mg/mL. Despite the lower dose and concentration of rhBMP-2, this study suggests that fusion success with INFUSE is equivalent to ICBG for posterolateral spine fusion. As with ICBG, development of solid fusion or nonunion is a multifactorial process. The use of INFUSE is not a substitute for proper surgical technique or optimization of patient-related risk factors. Additional studies are needed to determine the incremental benefit of a greater rhBMP-2 dose or use of alternative carriers for posterolateral fusion. Finally, correlation between radiographic findings and clinical outcomes, and a cost-benefit analysis are needed. Despite these issues, this study presents compelling evidence that commercially available INFUSE is an effective ICBG substitute for one- and two-level posterolateral instrumented spine fusion.

Lumbar degenerative classification study.

The purpose of this study was to develop and validate a classification of indications for fusion in lumbar degenerative disease. Nineteen spine surgeons reviewed a series of 32 case histories and selected the indication for fusion based on an outlined classification system. To determine the degree of interrater variability, K coefficients were calculated (K for all 32 cases, 0.63). Results from this study show the significant difficulty in classifying the indication for fusion in lumbar degenerative disease. The level of the 19 surgeons' agreement regarding surgical indication was only moderate, despite a study design that eliminated controversial issues of patient and procedure selection. To a significant extent, the difficulty in classifying indication for fusion underlines the importance of the process. If we cannot agree on why a specific patient is selected for fusion, it is then impossible to accurately compare outcomes for a given disease process or surgical technique. For this reason, an ongoing effort to refine nomenclature and classification is necessary.

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.