We report a long-term follow-up of abduction-extension osteotomy of the first metacarpal, performed for painful trapeziometacarpal osteoarthritis. Of a consecutive series of 50 operations, 41 thumbs (82%) were reviewed at a mean follow-up of 6.8 years. Good or excellent pain relief was achieved in 80%, and 93% considered that surgery had improved hand function, while 82% had normal grip and pinch strength, with restoration of thumb abduction. Trapeziometacarpal osteoarthritis is associated with degeneration of the palmar beak ligament 10 and articular degeneration starts on the joint surfaces adjacent to it. The cartilage of the dorsoradial joint surface is spared until late in the disease process. 10 A recent cadaver study has shown that extension osteotomy of the first metacarpal shifts the area of joint contact from the worn palmar cartilage to the normal dorsal surface. 11 We describe our experience of osteotomy in a large series of patients over a period of 12 years.
Patients and MethodsWe carried out 50 operations in 42 patients; 41 thumbs (82%) in 33 patients were available for review at a mean of 6.8 years (2 to 12) from operation. The average age at operation was 57 years (20 to 73). Nine of the operations were in men and 32 in women, and the dominant hand was involved in 20 patients. Nine patients were lost to followup. Three had died, one had moved and could not be contacted, and three very elderly patients could not be traced. Another elderly man was too confused to co-operate. One patient was contacted by telephone but did not wish to be reviewed. When last seen she had complete relief of pain, full abduction and a strong grip. The patients were reviewed by a surgeon who had not been involved in the operation. Pain and hand function were assessed by the patient, using a self-administered questionnaire. Grip strength was measured with a Jamar dynamometer (Asimov Engineering Company, Los Angeles, California), and pulp to pulp (pinch) and lateral pinch (key-grip) with a B & L hydraulic pinch meter (B&L Engineering, Santa Fe Springs, California). The mean of three readings was compared with normal ranges matched for age and sex. 12 The range of movement and maximum abduction were measured clinically with a goniometer. Thumb opposition and the ability to flatten the palm were assessed and recorded. Indications for operation. Surgery was carried out when pain which interfered with everyday activities had not responded to conservative treatment with a splint, nonsteroidal anti-inflammatory drugs or injection with lignocaine and hydrocortisone. Osteotomy was only considered for mild and moderate degenerative changes confined to the trapeziometacarpal joint, scaphotrapezial wear being a contraindication. The preoperative radiographs were graded as described by Eaton and Littler 13 : grade 1, no radiological changes; grade 2, osteophytes or intra-articular fragments of <2 mm with no narrowing of