Reconstruction of complex hand defects using trapezoidal osteocutaneous free fibular flap.

BACKGROUND

Traumatic defects of multiple metacarpal bones can be addressed using conventional or vascularized bone grafts. When associated with extensive skin and tendon loss, the treatment becomes more challenging. The aim of the study was to describe the results of using free osteocutaneous fibular flap placed in a new fashion for the reconstruction of complex hand defects.

PATIENTS AND METHODS

Six patients with complex hand defects underwent reconstruction using free osteocutaneous fibular flap placed in trapezoidal fashion with two-stage tendon reconstruction using fascia lata graft. The mean age at the time of injury was 34.7 years (range: 14-54 years). The injury was caused by motor vehicle accident in four patients, machine injury in one patient, and falling from height in one patient. All patients had extensive three or four metacarpal bones defects, segmental loss of tendons, and large skin defect ranging from 6 × 10 cm to 10 × 15 cm. The fibular graft was divided into three segments and positioned in a trapezoidal fashion with the middle bone segment placed transversely to support the bases of the proximal phalanges while the first and third bone segments were placed obliquely along the metacarpal axis converging toward the remaining metacarpal bases and/or carpal bones. At final follow-up visit, the finger range of motion was assessed using the total active motion (TAM) scoring system. Functional outcome was evaluated by the disabilities of the arm, shoulder and hand (DASH) score. Active range of motion (AROM) of the pseudo-metacarpophalangeal (MP) joint was measured. The handgrip strength was measured using Jamar hydraulic dynamometer.

RESULTS

The mean length of the harvested fibular graft was 18 cm (range: 17-19). The mean size of the skin paddle was 7.5 × 13.1 cm (range: 6 × 10 cm to 10 × 15 cm). Fibular flaps survived in all patients. The mean follow-up period was 30.8 months (range: 24-40 months). The mean time to achieve bone healing was 3.8 months (range: 3-5 months). The mean TAM was 185° (range: 165-204°) and TAM percentage was described as excellent in two patients and good in four patients. The mean AROM at the pseudo-MP joint was 53.8° (range: 42-70°). The mean injured handgrip strength was 27.3 kg (range: 23-31 kg) and the mean grip strength ratio was 74.8% (range: 69-80%). The mean DASH score was 19.6 (range: 11.67-26.67). Pin tract infection, partial skin paddle necrosis, and wound infection were reported.

CONCLUSION

The fibular osteocutaneous flap arranged in trapezoidal fashion is a viable choice for the reconstruction of complex hand defects, particularly when the metacarpophalangeal joints are not preserved.