Extensor Indicis Proprius Tenodesis to Correct Finger Ulnar Drift Deformity in Rheumatoid Arthritis.

The most frequent deformity of the hand occurring in patients with RA affects the metacarpophalangeal (MCP) joint and it is characterized by a volar subluxation of the proximal phalanges and ulnar drift of the fingers. The Extensor Indicis Proprius (EIP) tenodesis for correction of ulnar deviation of fingers (II to V) was performed in 10 hands (40 fingers and 5 patients). There was complete correction of the subluxation or dislocation and almost complete correction of the ulnar drift of the metacarpophalangeal joints at the initial postoperative evaluation (three to four months after surgery). However, at final evaluation (eight to twelve months after the operation), all of the digits had some recurrence of ulnar deviation. The EIP tenodesis provides a correct forces vector to maintain the fingers in proper alignment following correction of ulnar deviation.