Clinical results with ProDisc: European experience and U.S. investigation device exemption study

This study is based on a review of the literature related to the use of the ProDisc device and a report of the preliminary results of a prospective randomized study.

To review European results related to the use of the ProDisc device and compare the results of this device to lumbar fusion in a prospective, randomized study being performed as part of a Food and Drug Administration-approved investigational study.

There are two devices that have been used on a large-scale basis for total disc replacement. These are the SB Charitè and the ProDisc. Both devices were created in Europe and have been used there for more than 10 years. Reported results for these devices have been favorable, but there have been no prospective studies evaluating the outcome.

The literature related to the ProDisc was reviewed. The preliminary study data were based on one center's experience participating in the Food and Drug Administration Investigation Device Exemption study. There were 39 patients with a minimum 6-month follow-up. Patients were randomly assigned to receive either the ProDisc or undergo a combined anterior-posterior lumbar fusion in a ratio of 2:1 (ProDisc to fusion). Patients completed standardized questionnaires before surgery and at 6 weeks, 3 months, and 6 months after surgery. Data collection is continuing for the 12- and 24-month follow-up. RESULTS Operative time, blood loss, and length of hospitalization were significantly less in the disc replacement group (P < 0.05). At the 3-month follow-up, the disc replacement group had a significantly greater improvement in Oswestry scores than did the fusion group. There were no differences in pain scores as measured by visual analog scales. Disc replacement patients had greater motion and there was a trend for this group to have greater satisfaction at the 6-month follow-up.

The preliminary results of this prospective randomized study found that peri-operative factors were more favorable in the disc replacement group than in the fusion group. There was a trend to greater patient satisfaction in this group. These early results suggest that total disc replacement may be a viable alternative to lumbar spinal fusion in patients with symptomatic disc disruption unresponsive to nonoperative care. Long-term follow-up is needed and is currently being collected for this study group.