[Reconstruction of metacarpophalangeal joint defect by the second toe proximal interphalangeal joint with skin flaps]

To investigate the operative method and clinical efficacy of reconstructing metacarpophalangeal joint defect by the second toe proximal interphalangeal joint with skin flaps.

From March 2003 to January 2008, 26 cases (26 fingers) with metacarpophalangeal joint defect were treated, including 19 males and 7 females aged 18-36 years old (average 27 years old). Among them, 23 cases were caused by mechanical injury and the time from injury to operation was 1-6 hours; while 3 cases suffered from secondary injury due to trauma and the time from injury to operation was 3-12 months. Four thumbs, 10 index fingers, 8 middle fingers, 3 ring fingers and 1 little finger were injured. The metacarpophalangeal joint defects were 2 cm x 1 cm - 4 cm x 2 cm in size, and 22 cases were combined with skin and soft tissue defect (1.5 cm x 1.5 cm - 6.0 cm x 5.0 cm). During operation, the second toe proximal interphalangeal joint with skin flaps was transplanted to reconstruct those defects, 20 fingers received whole-joint transplantation and 6 fingers received half-joint transplantation. The skin flaps ranging from 2.0 cm x 1.5 cm to 6.5 cm x 6.0 cm in size were adopted. The donor site of 21 cases received toe amputation, and the rest 5 cases received joint fusion.

The transplanted joints and skin flaps of all the 26 fingers survived. All incisions and donor sites healed by first intention. All patients were followed up for 6-20 months (average 12 months). The union of transplanted joints was achieved in all the cases at 6-12 weeks after operation, no bone nonunion and refracture occurred. The flexion range of transplanted metacarpophalangeal joints was 30-75 degrees (average 45 degrees). Joint activity was evaluated according to the total active movement/total passive movement assessment criteria, 8 fingers were excellent, 13 good, 3 fair, 2 poor, and the excellent and good rate was 80.77%. The foot donor-site ability to walk was unaffected.

Applying second toe proximal interphalangeal joint with skin flaps is an effective approach to reconstruct the metacarpophalangeal joint defect, and the function recovery of the injured joints is satisfying.