A randomized prospective study of posterolateral lumbar fusion outcomes with and without pedicle screw instrumentation

Study Design. A prospective evaluation of the clinical and radiographie outcomes of 71 patients who underwent lumbar fusion, with or without transpedicular instrumentation. The patients completed a questionnaire that determined pain relief, medication use, return to work, and overall satisfaction with surgery. Objectives. To explore the effect, if any, of instrumentation on the outcome of lumbar fusion surgery, according to reports of the patients, and whether there is a correlation between the radiographie determination of a solid fusion and the same patient-reported outcome. Summary of Background Data. The literature on this topic reports pseudarthrosis rates from 0% to 57% and good to excellent results from 56% to 95%. These studies provide no clear-cut recommendations concerning the effect of added lumbar instrumentation on patient-reported outcome in a prospective manner using concurrent control subjects. Methods. The patients were randomized to groups with and without instrumentation after deciding to undergo a lumbar fusion and consenting to enter the study. Radiographs were obtained and questionnaires filled out at 6 weeks, 6 months, 1 year, and 2 years after surgery. Results. There was no statistical difference in patientreported outcome between the two groups. There was a slight nonsignificant trend toward increased radiographie fusion rate in the group with instrumentation that did not correlate with an increased patient-reported improvement rate. Conclusions. These results do not provide data that indicate a benefit in outcome from added instrumentation in elective lumbar fusions.