John A. McCulloch

Nonorganic physical signs in low-back pain.

Nonorganic physical signs in low-back pain are described and standardized in 350 North American and British patients. These nonorganic signs are distinguishable from the standard clinical signs of physical pathology and correlate with other psychological data. By helping to separate the physical from the nonorganic they clarify the assessment of purely physical pathologic conditions. It is suggested also that the nonorganic signs can be used as a simple clinical screen to help identify patients who require more detailed psychological assessment.

Microdecompression for Lumbar Spinal Canal Stenosis

STUDY DESIGN A description of the technique for lumbar microdecompression and a prospective study of the outcomes. OBJECTIVE To describe and analyze a technique that affords an excellent decompression while minimizing damage to surrounding tissues. SUMMARY OF BACKGROUND DATA Commonly used techniques of lumbar decompression that include bilateral takedown of paraspinal musculature and aggressive bony resection can result in significant iatrogenic sequelae. A less destructive alternative is needed. METHODS Unilateral limited takedown of multifidus was undertaken, and ipsilateral decompression performed. The contralateral side then was addressed under the midline structures with microscopic visualization--thereby preserving the supra-/interspinous ligament complex and the contralateral musculature. Thirty consecutive patients undergoing the procedure were analyzed prospectively and after a follow-up period by independent observers using a modified validated functional outcome score and patient satisfaction measures. RESULTS The technique affords an excellent decompression while minimizing destruction to tissues not directly involved in the pathologic process. Functional outcome scores doubled, and 87% of patients reported high satisfaction rates. CONCLUSIONS Lumbar microdecompression is a minimally invasive technique that appears to provide excellent functional outcomes.

A Pilot Study Evaluating the Safety and Efficacy of OP-1 Putty (rhBMP-7) as a Replacement for Iliac Crest Autograft in Posterolateral Lumbar Arthrodesis for Degenerative Spondylolisthesis

Study Design. A prospective, randomized, controlled, multicenter clinical study was conducted. Objective. To compare the clinical and radiographic outcomes of patients treated with OP-1 (BMP-7) Putty to autogenous iliac crest bone graft for one-level uninstrumented posterolateral fusion of the lumbar spine following decompressive laminectomy for the treatment of symptomatic degenerative spondylolisthesis with spinal stenosis. Background. Preclinical studies have demonstrated that osteoinductive recombinant human osteogenic protein1 in the form of OP-1 Putty is successful at achieving a posterolateral fusion in rabbits and dogs without any significant safety concerns. Methods. Thirty-six patients with degenerative lumbar spondylolisthesis and symptoms of neurogenic claudication were randomized (2:1) to either OP-1 Putty (3.5 mg of OP-1 per side) or autogenous iliac crest bone graft for one-level uninstrumented posterolateral fusion following a decompressive laminectomy. Enrollment in the study was complete when 24 OP-1 Putty patients and 12 autograft patients had been randomized and treated. A patient administered Oswestry scale and SF-36 scale were used to determine clinical outcomes. Independent, blinded neuroradiologists reviewed both static and dynamic radiographs to determine fusion status. Results. At the 1-year follow-up, 32 patients were available for clinical analysis and 29 patients were available for radiographic review. Clinical success as measured on the Oswestry scale was achieved by 18 of 21 (86%) OP-1 Putty patients and 8 of 11 (73%) autograftpatients. SF-36 pain index scores showed similar results. Fourteen of 19 (74%) OP-1 Putty patients and 6 of 10 (60%) autograft patients achieved a successful posterolateral fusion fulfilling all fusion criteria. Of the 29 evaluable patients, 15 were both clinical and radiographic successes, 5 were radiographic successes but were clinicalfailures, 1 patient was both a radiographic and clinical failure, and 8 patients were radiographic failures but were clinical successes. No systemic toxicity, ectopic bone formation, recurrent stenosis, or other adverse events related to the OP-1 Putty implant were observed. Conclusion. Although the posterolateral spine is a challenging fusion environment in patients with degenerative spondylolisthesis, successful radiographic fusion was obtained using OP-1 Putty at a rate that was similar to autograft given the number of patients in this study. Importantly, there were no apparent adverse consequences related to the use of the OP-1 Putty implant in this patient population.

Comparison of OP-1 Putty (rhBMP-7) to Iliac Crest Autograft for Posterolateral Lumbar Arthrodesis : A Minimum 2-Year Follow-up Pilot Study

Study Design. A prospective, randomized, controlled, multicenter clinical study. Objective. To compare the safety and clinical and radiographic outcomes of OP-1 (BMP-7) Putty to autogenous iliac crest bone graft in a population of patients undergoing laminectomy and posterolateral fusion for symptomatic lumbar stenosis associated with degenerative spondylolisthesis. Summary of Background Data. Although the existing preclinical and clinical data suggest that OP-1 is able to achieve osteoinduction and clinical fusion in a variety of situations, the efficacy of this recombinant protein in a clinical spine fusion population has not been fully elucidated. This study directly compares the efficacy and safety of OP-1 putty to autograft bone for arthrodesis in patients with symptomatic stenosis in association with degenerative spondylolisthesis. Methods. Thirty-six patients with degenerative lumbar spondylolisthesis and symptoms of neurogenic claudication underwent laminectomy, bilateral medial facetectomy, and posterolateral fusion using either iliac crest autograft or OP-1 Putty. Oswestry scores and SF-36 questionnaires were used to determine the clinical response to treatment. Independent, blinded neuroradiologists reviewed both static and dynamic radiographs to determine the fusion status. Successful fusion was declared whenthe presence of continuous bridging bone between the transverse processes was observed and less than 5° of angular motion and 2 mm of translational movement was measured using digital calipers. Results. Efficacy data were tabulated for 27 patients at the 24-month time point and an additional 4 patients (without evaluable 24-month results) at the 36-month time point. One patient was not evaluable for radiology, so the data reflect clinical information for 31 patients and radiology for 30 patients. Clinical success, defined as a 20% improvement in the preoperative Oswestry score, was achieved by 17 of 20 (85%) OP-1 Putty patients and 7 of 11 (64%) autograft patients. A successful posterolateral fusion was achieved in 11 of 20 (55%) OP-1 Putty patients and 4 of 10 (40%) autograft patients. SF-36 scores showed similar clinical improvement in both groups. No systemic toxicity, ectopic bone formation, recurrent stenosis, or other adverse events specifically related to the use of the OP-1 Putty implant were observed. Conclusion. This study represents the first clinical trial to demonstrate the safety and similarity of OP-1 Putty as a replacement for autogenous bone graft in the posterolateral fusion environment with a minimum of 2-year follow-up. OP-1 Putty was able to achieve osteoinduction leading to a radiographically solid fusion in the absence of autogenous iliac crest bone graft in 55% of the patients at 24 and 36 months. These results compare favorably to the historical fusion rates reported for uninstrumented arthrodesis in this challenging clinical scenario.

Focus issue on lumbar disc herniation : Macro- and microdiscectomy

&NA; This paper is based on a review, analysis, and discussion of the extensive literature on indications, technique, and complications of discectomy (macro and micro) for lumbar disc herniation. Outcomes for lumbar discectomy for disc herniation depend on patient selection. Short‐term results of discectomy are excellent when there is agreement between the clinical presentation and imaging studies. Long‐term results of surgery are only slightly better than conservative measures and the natural history of a lumbar disc herniation. A review of the literature reveals success rates for lumbar discectomy ranging from 80‐96%. The outcome of lumbar discectomy does not appear to be affected by the use of a microscope and depends more on patient selection than on surgical technique.

Consensus summary on the diagnosis and treatment of lumbar disc herniation

Clinicians must not simply decide that a patient with symptoms and a positive diagnostic test has a reason for a specific treatment, and likewise clinicians must not decide that a patient with symptoms and a negative test does not have a clinically important problem. We must also consider the sensitivity, specificity and predictive value of the diagnostic test and the individual characteristics of the patient. Treatment outcome depends on many factors. Point of service decisions vs population based decisions are obviously different. Each patient presents to the treating practitioner on a given day, at a given time, and it is this picture upon which a plan of care is formulated.