EFFICACY OF PEDICLE SCREW FIXATION IN THE TREATMENT OF SPINAL INSTABILITY AND FAILED BACK SURGERY - A 5-YEAR REVIEW

Object. The goal of this study was to review retrospectively the outco me of 95 patients with various disorders leading to instability of the thoracolumbar and lumbar spine who were treated consecutively via a p osterior surgical approach with pedicle screw fixation in which the Te xas Scottish Rite Hospital system was used. Methods. All cases were ma naged according to the same protocol. Follow-up review averaged 29.6 m onths. Radiographic evidence of osseous union and the patient's curren t status were analyzed. Four screws were malpositioned, and there were two dural lacerations of a nerve root and one pedicle fracture. Deep wound infections developed in five patients (5.2%), and three patients had postoperative radicular pain. In one case, the rods disengaged fr om the screws; in four cases, hardware was removed but there were no b roken screws. Neurological deficits improved in 85% of the surviving p atients, and no patient was worse neurologically after surgery. The ra te of osseous union was 96.8%. Three patients developed pseudarthrosis , one of whom was asymptomatic. Back pain improved in 80 patients. A s olid bone fusion, however, was not necessarily associated with decreas ed back pain. Conclusions. These results support the use of pedicle sc rew fixation as an effective and safe procedure for fusion of the thor acolumbar and lumbar spine and support the finding that complications can be minimal when a meticulous surgical technique is used. The prope r selection of patients for surgery is probably the most important fac tor associated with good outcomes.