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 outcome of 95 patients with various disorders leading to instability of the thoracolumbar and lumbar spine who were treated consecutively via a posterior surgical approach with pedicle screw fixation in which the Texas Scottish Rite Hospital system was used. Methods. All cases were managed according to the same protocol. Follow-up review averaged 29.6 months. Radiographic evidence of osseous union and the patient's current 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 from the screws; in four cases, hardware was removed but there were no broken screws. Neurological deficits improved in 85% of the surviving patients, and no patient was worse neurologically after surgery. The rate of osseous union was 96.8%. Three patients developed pseudarthrosis, one of whom was asymptomatic. Back pain improved in 80 patients. A solid bone fusion, however, was not necessarily associated with decreased back pain. Conclusions. These results support the use of pedicle screw fixation as an effective and safe procedure for fusion of the thoracolumbar and lumbar spine and support the finding that complications can be minimal when a meticulous surgical technique is used. The proper selection of patients for surgery is probably the most important factor associated with good outcomes.