ORTHOSIS AS PROGNOSTIC INSTRUMENT IN LUMBAR FUSION - NO PREDICTIVE VALUE IN 50 CASES FOLLOWED PROSPECTIVELY

To evaluate pain relief in a lumbar orthosis as a predictor for good c linical results after solid fusion, all patients scheduled for such a surgical procedure were preoperatively encouraged to use an orthosis, soft or rigid, for 3 weeks. Grade of back pain relief as a percent usi ng the orthosis was assessed by the patients and was registered before surgery. After surgery, at 1-year follow-up, patients with nonunion d emonstrated radiographically were excluded from the series. Thus, 50 p atients with solid fusion could be identified and followed for at leas t 2 years prospectively. At follow-up these 50 patients graded the pai n relief induced by the fusion. In the preoperative corset test, 31 pa tients experienced significant back pain relief, meaning a reduction o f at least 50%. No applicable correlation was found, however, between outcome in this corset test and the eventual clinical result expressed as improvement/no improvement after solid fusion. The two types of or thoses did not differ in this aspect. We conclude that the orthosis, r igid or soft, is not a useful instrument when selecting patients for l umbar fusion.