[Anchovy dacron arthroplasty in the treatment of basal osteoarthritis of the thumb: long term results].

Introduction: Fifteen patients were treated for arthritis of the base of the thumb by trapieziumectomy and anchovy interposition using Dacron[symbol: see text]. The results are described.

Methods: The 15 patients were between 42- and 68-years-old at the time of operation. The mean postoperative follow-up was 3 years. Pain, pinch strength, opposition, opening of the first web space and height of the space formerly occupied by the trapezium were clinically and radiologically evaluated.

Results: Pain had completely disappeared in more than 80% of the patients. The mean post-surgical opposition was 8.9/10 (Kapandji score). The pinch strength and first web-space opening were improved, whereas the height of the trapezium site was always reduced by 25%. The only complication was one case of reflex sympathetic dystrophy: no case of foreign body reaction was reported. Eleven of the 15 patients were satisfied with the operation, and noted better thumb function in everyday life.

Discussion: The treatment of arthritis of the base of the thumb by means of trapieziumectomy and anchovy interposition is effective with respect to pain in all the studies previously published, whatever the technique used. Mobility is preserved, contrary to arthrodesis, and grip strength remains compatible with the patient's daily life. The choice of a synthetic anchovy such as Dacron[symbol: see text] allows a quicker operation and better than the ones involving sacrifice of a tendon at the wrist. Anchovy interposition remains the preferred alternative among other procedures in the treatment of basal osteoarthritis of the thumb.