Comparison of results of total disc replacement in postdiscectomy patients versus patients with no previous lumbar surgery

Study Design. Data for this study were collected as part of a prospective Food and Drug Administration regulated IDE trial for the ProDisc total disc replacement. Objective. The purpose of the study was to compare the results of total disc replacement (TDR) in patients with previous discectomy to patients who had no such previous surgery. Summary of Background Data. Discectomy is a well accepted surgical procedure for appropriately selected patients. However, removal of a portion of the disc may lead to further disc degeneration and collapse of the disc space. In the past, treatment options for such patients included a variety of fusion procedures, particularly ones incorporating an interbody graft to restore disc space height. Currently, TDR is being used to treat symptomatic disc degeneration. The results of this procedure have not been specifically investigated in patients with previous discectomy. Methods. Data were drawn from 1 center participating in the IDE trial for ProDisc. Only patients reaching the 24-month follow-up period were included. Patients were divided into 2 subgroups: those who had previously undergone lumbar discectomy ( N = 20) and those who had not ( N = 67). Data for this study were collected prospectively before surgery, and at 6 weeks, 3, 6, 12, 18, and 24 months after surgery. The primary outcome measures used were visual analog scales ( VAS) assessing pain, Oswestry questionnaire, postoperative patient satisfaction measured on a 0 to 10 VAS, and asking patients if they would have the same procedure again. The outcome measures were compared between the 2 subgroups. Results. The results of this study found no differences between the 2 groups based on any of the 4 outcome measures used at any of the follow-up periods ( all P > 0.10). Both groups improved significantly from the preoperative baseline on the VAS assessing pain and the Oswestry questionnaire. The mean satisfaction scores were greater than 7.5 at all follow-up periods and more than 80% of patients in both groups indicated that they would have the same surgery again. Discussion. The results of this study indicate that the outcome of TDR is not compromised among patients with a history of previous discectomy. This finding supports TDR as a viable treatment for patients with symptomatic disc degeneration arising from a previously operated lumbar disc.