Perioperative complications with rhBMP-2 in transforaminal lumbar interbody fusion.

Bone morphogenetic protein (BMP) is commonly used as an ICBG substitute for transforaminal lumbar interbody spine fusion (TLIF). However, multiple recent reports have raised concerns regarding a substantial incidence of perioperative radiculopathy. Also, given the serious complications reported with anterior cervical BMP use, risks related to swelling and edema with TLIF need to be clarified. As TLIF related complications with rhBMP-2 have generally been reported in small series or isolated cases, without a clear denominator, actual complication rates are largely unknown. The purpose this study is to characterize perioperative complications and complication rates in a large consecutive series of TLIF procedures with rhBMP-2. We reviewed inpatient and outpatient medical records for a consecutive series of 204 patients [113 females, 91 males, mean age 49.3 (22-79) years] who underwent TLIF using rhBMP-2 between 2003 and 2007. Complications observed within a 3-month perioperative interval were categorized as to etiology and severity. Wound problems were delineated as wound infection, hematoma/seroma or persistent drainage/superficial dehiscence. Neurologic deficits and radiculopathies were analyzed to determine the presence of a clear etiology (screw misplacement) and identify any potential relationship to rhBMP-2 usage. Complications were observed in 47 of 204 patients (21.6%) during the 3-month perioperative period. Major complications occurred in 13 patients (6.4%) and minor complications in 34 patients (16.7%). New or more severe postoperative neurologic complaints were noted in 13 patients (6.4%), 6 of whom required additional surgery. These cases included one malpositioned pedicle screw and one epidural hematoma. In four patients (2.0%), localized seroma/hematoma in the area of the foramen caused neural compression, and required revision. In one additional patient, vertebral osteolysis caused foraminal narrowing and radiculopathy, but resolved without further surgery. Persistent radiculopathy without clear etiology on imaging studies was seen in six patients. Wound related problems were seen in six patients (2.9%), distributed as wound infection (3), hematoma/seroma (1) and persistent drainage/dehiscence (2). Overall, this study demonstrates a modest complication rate for TLIF using rhBMP-2. While perioperative complications which appeared specific to BMP usage were noted, they occurred infrequently. It will be necessary to weigh this incidence of complications against the complication rate associated with ICBG harvest and any differential benefit in obtaining a solid arthrodesis.

Difference in age at regression in children with autism with and without Down syndrome.

OBJECTIVE: Autism occurs more frequently in individuals with Down syndrome than it does in the general population. Among children with autism and Down syndrome, regression is reported to occur in up to 50%. The aim of this study was to characterize and compare regression in children with autism with and without Down syndrome. METHODS: In this case-control study, children with Down syndrome and autism characterized by a history of developmental regression (n = 12) were compared to children with autism with regression who did not have Down syndrome, matched for chronologic age and gender. Comparisons were made on age at acquisition of language and age at loss of language and other skills as measured by the Autism Diagnostic Interview-Revised (ADI-R). RESULTS: The mean age at acquisition of meaningful use of single words was 40.6 months (SD = 38.0) in children with Down syndrome and autism compared to 14.9 months (SD = 8.5) in children with autism without Down syndrome (p = .005). The mean age at language loss in children with autism with Down syndrome was 61.8 months (SD = 22.9) compared to 19.7 months (SD = 5.8) for those with autism without Down syndrome (p = .01). The mean age at other skill loss was 46.2 months (SD = 19.1) and 19.5 months (SD = 5.6), respectively (p = .006). CONCLUSIONS: When regression occurs in children with autism and Down syndrome it is, on average, much later than is typically seen in children with autism without Down syndrome.

Posterior iliac crest pain after posterolateral fusion with or without iliac crest graft harvest.

BACKGROUND CONTEXT: Considerable debate exists regarding the incidence of persistent pain from the iliac crest bone graft (ICBG) harvest site. Different study designs have led to a variety of reported rates. PURPOSE: The purpose of this study was to determine the incidence and severity of bone graft site pain after iliac crest harvest. STUDY DESIGN: Cross-sectional. PATIENT SAMPLE: One hundred and twelve patients, who had a posterior lumbar fusion, seen at a tertiary spine center for a routine postoperative visit. OUTCOME MEASURES: Numeric rating scales (0-10) for pain over lower back, right, and left posterior iliac crests. METHODS: An independent investigator, not directly involved in the care of the patient and unaware of the type of bone graft used in the fusion, examined the patient for tenderness over the surgical site as well as the left and right posterior iliac crest. After the examination, data on the source of grafting material, complications during harvest, and backfilling of the graft site defect were collected from the medical records. The patients were then classified as to whether ICBG was harvested or not. Chi-square test was used to determine any difference in the proportion of iliac crest pain between the bone graft group and no bone graft group. Correlations between body mass index (BMI), time since surgery, and the incidence and severity of bone graft site pain were also determined. RESULTS: There were 72 women and 40 men with a mean age of 56.6 years (range, 16-84). Mean follow-up was 41 months (range, 6-211 months) with a median of 25 months. Iliac crest bone graft was harvested in 53 (47.3%) patients through the midline incision used for lumbar fusion. In 59 patients (52.7%), recombinant human bone morphogenetic protein-2 was used with no graft harvest. There was no statistically significant difference in the proportion of patients complaining of tenderness over both or either iliac crest between the two groups. Only 10 patients had pain over the same crest from which the graft was harvested. No correlations between number of levels fused, levels fused, BMI, length of follow-up, and the incidence and severity of bone graft site pain were seen. CONCLUSIONS: The results of this study highlight the difficulty in differentiating pain originating from the graft site versus residual low back pain. The incidence of pain over the iliac crest was similar in patients in which iliac crest was harvested and those in which no graft was harvested.

Health-related quality of life improvements in patients undergoing lumbar spinal fusion as a revision surgery.

STUDY DESIGN: Retrospective cohort analysis. OBJECTIVE: To investigate health-related quality of life improvements in patients undergoing lumbar fusion to revise a previous lumbar spine surgery. SUMMARY OF BACKGROUND DATA: Spinal fusion is often used as a surgical intervention in patients who have previously undergone lumbar surgery. Prior studies suggest results that are inferiorto primary fusions. However, most of these studies are based on subjective surgeon evaluations, lack patient-reported outcomes, and include various diagnoses such as prior discectomy, adjacent level degeneration, and nonunion. METHODS: From a single-center database, we identified 171 patients who underwent lumbar fusion to revise a previous lumbar spine surgery. All had prospectively collected outcome measures at a minimum 2-year follow-up. The study group included 91 patients who had previous discectomy or laminectomy, 42 patients undergoing revision for adjacent segment degeneration (ASD) and 38 patients undergoing revision for nonunion. All patients completed the Oswestry Disability Index (ODI), MOS Short Form 36 (SF-36), and back and leg pain numerical rating scores before surgery and at 1 and 2 years after surgery. We compared mean changes in outcome measures and percentage of patients reaching the minimum clinically important difference (MCID) threshold in the 3 groups. Logistic regression analysis was performed to identify preoperative factors which could predict significant improvement. RESULTS: Statistically significant improvements were noted in back pain, leg pain, and ODI in all 3 groups. Postdecompression and ASD patients demonstrated significant improvements in SF-36 PCS at 2 years, while nonunion patients did not. A total of 49% of postdecompression patients, 38% of ASD patients, and 29% of nonunion patients reached the MCID for ODI. About 46% of postdecompression patients, 40% of ASD patients, and 24% of nonunion patients reached the MCID for SF-36 PCS. Significant improvement from index surgery was the only factor which able to predict reaching the MCID for ODI, while worker's compensation and narcotic use predicted failure to reach the MCID for SF-36 PCS. CONCLUSION: The current study demonstrates that patients undergoing lumbar fusion as a revision of a prior lumbar surgery can expect only modest improvements in health-related quality of life. Postdecompression patients achieved moderate improvements in clinical outcome measures, whereas ASD and nonunion patients showed only modest improvements. Further investigation is needed to identify preoperative predictors that will assist the selection of patients who will benefit from revision lumbar fusion.

Lumbar lordosis restoration following single-level instrumented fusion comparing 4 commonly used techniques.

A major sequelae of lumbar fusion is acceleration of adjacent-level degeneration due to decreased lumbar lordosis. We evaluated the effectiveness of 4 common fusion techniques in restoring lordosis: instrumented posterolateral fusion, translumbar interbody fusion, anteroposterior fusion with posterior instrumentation, and anterior interbody fusion with lordotic threaded (LT) cages (Medtronic Sofamor Danek, Memphis, Tennessee). Radiographs were measured preoperatively, immediately postoperatively, and a minimum of 6 months postoperatively. Parameters measured included anterior and posterior disk space height, lumbar lordosis from L3 to S1, and surgical level lordosis.No significant difference in demographics existed among the 4 groups. All preoperative parameters were similar among the 4 groups. Lumbar lordosis at final follow-up showed no difference between the anteroposterior fusion with posterior instrumentation, translumbar interbody fusion, and LT cage groups, although the posterolateral fusion group showed a significant loss of lordosis (-10°) (P<.001). Immediately postoperatively and at follow-up, the LT cage group had a significantly greater amount of lordosis and showed maintenance of anterior and posterior disk space height postoperatively compared with the other groups. Instrumented posterolateral fusion produces a greater loss of lordosis compared with anteroposterior fusion with posterior instrumentation, translumbar interbody fusion, and LT cages. Maintenance of lordosis and anterior and posterior disk space height is significantly better with anterior interbody fusion with LT cages.

Complications and concerns with osteobiologics for spine fusion in clinical practice.

STUDY DESIGN: Literature-based topic review. OBJECTIVE: To review the complications and the concerns that may be associated with all of the commonly used osteobiologic options for spine fusion. SUMMARY OF BACKGROUND DATA: Obtaining a solid arthrodesis is an important objective in many lumbar surgical procedures, and a wide array of bone graft materials may be used in an attempt to achieve this goal. Iliac crest bone graft, as well as all of the available osteobiologic alternatives, carries potential risks and concerns for both patient and surgeon. METHODS: Review of literature and expert opinion. CONCLUSION: Some of the potential complications associated with osteobiologic materials used in spinal fusion are well understood and clearly documented whereas others require further study and clarification. In any given clinical situation, the patient and surgeon need to balance the benefits and performance characteristics of the graft material with the risk profile to optimize clinical management.

Identification and surgical treatment of primary thoracic spinal stenosis.

We report the surgical treatment results for 7 patients (4 men, 3 women; mean age, 49 years) who presented with myelopathy caused exclusively by primary thoracic spinal stenosis, predominantly in the lower thoracic spine. (Patients with concurrent ascending lumbosacral degenerative disease were excluded.) All patients received extensive nonoperative treatment before referral to our center. Surgical treatment consisted of wide posterior decompression and instrumented fusion (5 cases), anterior vertebrectomy and fusion (1), and anterior vertebrectomy with autograft strut followed by wide posterior decompression and instrumented fusion (1). Mean operative time was 313 minutes, mean blood loss was 944 mL, and there were no major postoperative complications. Minimum follow-up was 2 years. Five patients had significant improvement in myelopathy and were ambulating normally, 1 had modest improvement in ambulation, and 1 remained wheelchair-bound. All patients achieved solid radiographic fusions. After presenting these case studies, we review the current literature on treatment effectiveness. Primary thoracic spinal stenosis should be considered in patients who present with isolated lower extremity myelopathy, particularly when no significant pathologic findings are identified in the cervical or lumbosacral spine. Expedient wide decompression with concurrent instrumented fusion is recommended to prevent late development of spinal instability and recurrent spinal stenosis.