Clinical Analysis of Re-Operation after Thoracic and Lumbar Spinal Fusion Surgery

OBJECTIVE: The purpose of this study is to review retrospectively 28 patients with re-operation due to complications related to instrumentation from thoracic and lumbar spinal fusion surgery. METHODS: A total of 285 patients underwent spinal fusion surgery with instrumentation between 1996 and 2000. Of these, 11 men and 17 women(mean age 46 years, range 21 to 69 years) presented with complications related to instrumentation. Previous surgery was preformed for vertebral column instability secondary to fracture(4), spondylolisthesis(12), failed back surgery syndrome(7), osteomyelitis(1), herniated nuclus pulposus(4). All patients underwent repeated spinal surgery including removal of instrument, new instrument fixation, or I & D. The mean follow-up period after second operation was 19 months. RESULTS: The complications related instrumentation system include six interbody fusion system retropulsion, eight screw loosenings, five screw fractures, three screw malpositions, three osteomyelitis, and one donor site infection. After repeated surgery, eight became asymptomatic and did not require further treatment, but eleven showed persistent low back pain without neurological deficits and the remaining nine continued to have nerve root deficits. CONCLUSION: In conclusion, spinal fusion surgery with instrumentation offers an immediate postoperative stability of the thoracic and lumbar spine and enhances early fusion. However, it may be associated with few, but significant, complications which may permanantly. The proper selection of patients and meticulous surgical technique for surgery are probably the most important factors associated good outcomes and prevention of complications.

A Histopathologic Study of the Iris in a Patient with Exfoliation Syndrome

The pathogenesis of the exfoliation syndrome is still unknown. To clarify the etiology of the exfoliation syndrome, we examined the iris taken from a patient with exfoliative glaucoma during cataract surgery using light microscope, polarization microscopy and electron microscopy. The amorphous substance around the iris pigment epithelium and stroma were stained purplish red in PAS staining and showed purplish red metachromasia in toluidine blue staining. In electromicroscopic examination, we observed that many fibrillar materials were deposited at basement membrane and partially detached basement membrane around the pigment epithelium of the iris. Therefore we concluded that the exfoliative materials in this syndrome is a sort of glycoprotein and originated from the abnormal synthesis and metabolism of the basement membrane in the eye.