Spine
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Thirty patients who had posterior vertebral fusion for scoliosis, performed without metallic implants, were examined using computer-assisted tomography to study the configuration of the evolving fusion mass. It was observed that the deposition of bone followed lines of force, according to Wolff's Law. ⋯ Further, it was observed that usually the fusion mass, seen in section, has a hollow "box-section" shape, which means that a resorption of unstressed central bone occurs. The hypothesis that the torsional forces are the predominant forces acting on the scoliotic spine can explain the characteristic "box-section" of the CT scans obtained.
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A clinical study was undertaken to formulate better criteria for accurate diagnosis of the lumbar facet syndrome and for predicting treatment response to facet joint injection. Twenty-two consecutive patients with a clinical diagnosis of lumbar facet syndrome, made by conventional diagnostic criteria, who were then treated with facet joint injection, were reviewed for their treatment responses. New diagnostic criteria were formulated based on a scoring system derived from the values observed in this review study. ⋯ A score of 60 points or more indicates a very high probability of satisfactory response to facet joint injection (100% prolonged response in this study). When only the conventional criteria were used, the overall results of prolonged relief of pain after facet joint injection was 50%. A "scorecard" system is proposed that may give a higher degree of diagnostic accuracy and predictability of successful response to facet joint injection.
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Vertebral transpedicular screws provide secure attachment for posterior spinal fixation devices. Screw design details, biomechanics, and implantation safety depend upon anatomic constraints, especially from the pedicle and body. Previous morphometric data were limited; thus, a retrospective study was undertaken using computerized axial tomograms (CT) of 91 vertebrae (T9-L5). ⋯ Good correlation is shown to occur between CT scan and direct physical measurements of human vertebrae. Implications for spinal implant screw dimensions and safety of implantation are discussed. Comparison with previously available data is made.
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The development of a new scale, the Somatic Amplification Rating Scale (SARS), for the quantification of exaggerated (nonorganic) motor, sensory, and pain responses occurring during a standardized physical examination is described. This 13-item scale, partially based on a measure of nonorganic physical signs developed by Waddell et al, was administered to 127 low-back pain patients at an outpatient pain center. ⋯ Interrater reliability of the finalized seven-item scale was excellent (R = 0.93). Finally, it was determined that patients with high SARS scores were significantly more likely to be receiving workers' compensation benefits and to endorse physical symptoms with greater intensity on psychologic testing (Symptom Checklist 90).