Correction of swan neck deformity in rheumatoid arthritis using a new lateral extensor band technique.

Swan neck deformity is a progressive and disabling condition that commonly affects rheumatoid arthritic hands. During a 4-year period, 101 fingers in 43 patients had this deformity corrected using a new procedure combining the distally based extensor lateral band technique described by Littler and the flexor digitorum superficialis (FDS)-palmar plate pulley introduced by Zancolli. The ranges of motion of the metacarpophalangeal, proximal interphalangeal (PIP) and distal interphalangeal (DIP) joints were assessed pre-operatively and 12 months after surgery. An average PIP joint hyperextension of -13.3 degrees was converted to +13.4 degrees . The ranges of motion of the proximal and DIP joints were significantly different (Student's t-test). No patient suffered recurrence of the deformity during an average follow-up of 20 months. This new technique improves some unappealing aspects of previous techniques and provides a stable and reliable correction of swan neck deformity.