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Outcomes of Revision of Interposition Implant Trapeziometacarpal Arthroplasty.

BACKGROUND
Implant arthroplasties for trapeziometacarpal osteoarthritis are often associated with high complication and revision surgery rates. There are no previous studies reporting revision outcomes of failed interposition implant arthroplasty.


METHODS
A patient register search was done for all implant arthroplasties performed for trapeziometacarpal osteoarthritis during a 10-year period in a single hand surgical unit. Altogether, 32 patients had primary interposition implant arthroplasty (Artelon 22, Pyrosphere 6, Ortosphere 2, and Pyrodisk 2), and 19 of these patients had revision surgery with 23 revision procedures performed. In all, 15 of the revised 19 patients were reexamined clinically (Connolly-Rath score, Quick Disabilities of the Arm Shoulder and Hand, patient evaluation measure, the visual analog score for pain, thumb range of motion and strength measurements) and radiographically.


RESULTS
The indication for revision surgery was pain alone or implant dislocation accompanied by pain in all cases. Thirteen of the revised 15 patients reported functional deficit and pain after revision. There was no statistically significant difference in the revision outcomes between patients operated on primarily with the Artelon implant versus pyrocarbon/ceramic implants. Compared to previous studies on revision surgery and primary trapeziometacarpal arthroplasty, our results showed slightly higher pain and poorer functional scores.


CONCLUSIONS
Interposition implant arthroplasty may yield high revision rates. The results after revision surgery may be worse than previously described, and there may also be a tendency for worse results than those of primary arthroplasty. Interposition implant arthroplasty should always be thoroughly contemplated.