Short Term Outcomes of Intervertebral Spike (IS(R)) Cage for Degenerative Lumbar Spinal Disorders

ABSTRACT

OBJECTIVE: The authors conducted a retrospective study of patients with degenerative lumbar spinal disorders who received a posterior lumbar interbody fusion (PLIF) with the IS(R) cage. METHODS: We assessed 105 patients who underwent on a PLIF with or without pedicle screws using the IS(R) cage in our institute from November 2007 to December 2008. Clinical outcomes were analyzed with a Visual Analog Scale (VAS) for back and leg pain. Radiographs were obtained before and after the surgery. In some cases, a lumbar spinal computed tomography scan was obtained. Radiological outcomes of intercage distance, fusion rate, and intervertebral disc height were assessed. In scoliosis or lateral translation, the extent of correction was examined. RESULTS: The mean VAS score for back pain improved from 6.86 preoperatively to 2.66 at postoperative month 12, and the score for leg pain decreased from 7.92 to 1.78. The mean intervertebral disc height was 8.71+/-2.35mm before the surgery, and it increased to 11.67+/-1.77mm at 7 days postoperative and decreased to 9.57+/-1.90mm at 6 months postoperative. The fusion rate was 95.65%. For scoliosis or lateral translation, thesegmental angle of scoliosis decreased from 11.10+/-5.82degrees before the surgery to 5.61+/-3.71degrees by month 6 postoperative. The extent of the lateral translation changed from 6.04+/-1.73mm before the surgery to 3.56+/-4.99mm at month 6 postoperative. CONCLUSION: There have been low complication rates with the IS(R) cage during the follow-up period, and the results of this study demonstrates a wide fusion area, partial reduction of lateral translation and scoliosis, good clinical success, and a high fusion rate.