REVISION OF FAILED LUMBAR DISC REPLACEMENT

Abstract

This study was carried out in order to document the indications, methods, complications and results of revision lumbar disc replacement surgery.

Out of a total series of 29 disc replacement operations carried out by the senior author 8 patients have required revision (10 operations). All of these patients have been followed prospectively since their initial operation and data was extracted from the case notes, theatre logs and radiographs.

The primary indications for revision were recurrence of, or failure to relieve back pain. Of the 8 patients requiring revision for their symptoms, 3 had prostheses that had clearly failed on CT. Four patients had the pros-thesis removed and were revised to a circumferential fusion using iliac crest autologous bone graft anteriorly and pedicle screws posteriorly. Three patients had a posterolateral fusion only using pedicle screw fixation with retention of the prosthesis. Two patients had a posterior procedure carried out which failed to resolve the situation satisfactorily, and subsequently had the prosthesis removed and interbody cage fusion. Out of the 6 anterior cases there were 2 injuries to the great veins requiring vascular repair. There were few complications with posterior surgery. Although numbers are small, the patients who had anterior surgery seemed to do better than those retaining their prosthesis with posterior surgery alone.

We conclude that a posterolateral fusion is a safe but symptomatically unsatisfactory revision strategy for failed disc replacement, and that anterior revision with conversion to inter-body fusion is a better option but has a higher rate of surgical morbidity.