OBJECTIVE: To evaluate the effectiveness of anterolateral thigh and groin conjoined flap in emergent repair of ultra-long complex tissue defects in forearm and hand. METHODS: Between February 2009 and October 2011, 6 patients with complex tissue defect of dorsal forearm and hand were in adminsion. There were 5 male and 1 female with an average age of 38.5 years (range, 32-47 years). Injury reasons included machine injury in 5 cases and traffic accident injury in 1 case. Injury to admission time was from 3 to 16 hours (mean, 6 hours). All case were single limb injury, including right forearm and hand injury in 4 cases and left forearm and hand injury in 2 cases. The wound area was from 36 cm x 9 cm to 48 cm x 12 cm. The type of associated injury included elbow dislocation associated with open injury in 2 cases; fractures of the radial, ulnar, and metacarpal bone in 4 cases; defects of wrist dorsal skin and extensor tendons of fingers and wrist in 5 cases; and defects of ulnar artery and ulnar nerve in 1 case. The anterolateral thigh and groin conjoined free flaps were used to repair defects in the forearm and hand in emergency. The area of flap was from 36 cm x 9 cm to 48 cm x 12 cm. Meanwhile the partial functional reconstruction was performed. The donor site was repaired by skin grafts. RESULTS: The anastomotic embolization of vascular pedicle and arteria interossea dorsalis occurred in 1 case, purulent secretion under the flap in 1 case, which were cured after symptomatic treatment; the skin flaps completely survived, and primary healing of the wounds were obtained in the other cases. The donor skin grafts survived in 2 cases, and partial necrosis of the skin graft of lower abdominal occurred in 4 cases, and healed after changing dressing. All of the 6 patients were followed up 3 to 18 months (mean, 10 months). The appearance and texture of the flaps were good. The protective sensation was recovered in 2 cases followed up for more than 14 months; no sensory recovery was observed in the other cases. At last follow-up, according to the upper extremity functional evaluation standard by Hand Surgery Branch of Chinese Medical Association, the results were excellent in 1 case, good in 4 cases, and poor in 1 case, and the excellent and good rate was 83.3%. CONCLUSION: It could get a good short-term effectiveness to use the anterolateral thigh and groin conjoined flap for emergent repair of the ultra-long and complex tissue defects in forearm and hand.