WRIGHTINGTON EXPERIENCE OF HERBERT ULNAR HEAD REPLACEMENT

Abstract

Distal radioulnar joint surgery has been dominated by different types of partial or complete ulnar head excision. This remains a reasonable option in rheumatoid surgery. However, in the long run, this can create a number of problems. We have used Herbert modular prosthesis to tackle these very difficult situations. This prosthesis comprises of a press fit stem in three sizes and a ceramic head, also available in three sizes.

In Wrightington hospital upper limb unit 61 patients underwent Herbert ulnar head replacement. Fifty-eight were clinically and radiologically reviewed.

Between December 1998 and December 2002 21 male and 27 female patients were operated. The mean age was 49.8 years with a range of 28–72 years. Twenty two left, eighteen right and two bilateral replacements were performed. The mean follow-up was 20.02 months with a range of 3–60 months.

All patients were reviewed by an independent observer using range of motion, grip strength and satisfaction as outcome.

Primary diagnoses included failed Darrach, Bower, Sauve Kapandji and traumatic ulnar head excision. Forty-five patients were satisfied with the outcome. Pain score showed a mean improvement of 4 with a range of 0–10. The grip strength compared to normal side was decreased in 50% of the patients. The range of motion compared to normal side improved by a mean of 10 degrees (range 3–20) in supination and 13 (range 4–23) in pronation.

Radiological review showed new bone (8) and notch formation (9). Stress shielding of 0–19mm was observed in distal ulna with revision or emergency stem.

Complication occurred in eight patients instability (4), RSD (1), implant failure (1) and two others. Twelve patients required further surgery. No loosening was observed at revision.

Conclusion: This is a suitable revision and primary replacement but no long term following is required.