Finger reconstruction distal to the proximal interphalangeal (PIP) joint is a challenging task for hand surgeons. Although extended reverse dorsal metacarpal artery (RDMA) flaps were described for coverage of finger defects, reports on repairs beyond the PIP joint are limited. The occurrence of venous congestion of the flaps and their treatments require further clarification.
Extended RDMA flaps were used to cover the finger defects extending from the PIP joints to the fingertips in a series of 16 patients. The reconstructed fingers included the index, middle, ring, and little fingers; thumb reconstruction was not included in this study. The flap size ranged from 2.5 × 1.8 to 5 × 3 cm. A composite flap with a segment of tendon was applied for a complex reconstruction in 4 cases. Either superficial branch of radial nerve or dorsal branch of ulnar nerve was included in flap elevation because of its perineural vascular network contributing to the flap perfusion. The pivot point was located at the level of the middle point of the proximal phalanx, where the communicating branches between the proper palmar digital artery and the dorsal metacarpal artery exist. A teardrop skin pedicle was used to reduce the tension of the flap pedicle.
All flaps totally survived except that 1 flap had epidermal loss later salvaged by secondary skin grafting. Venous congestion occurred in the distal part of 5 flaps and was effectively relieved after multiple subcutaneous heparin injections. Neither of the 2 cases of nerve repair resulted in significant improvement in sensation. All donor sites were primarily closed.
Extended RDMA flaps can be effectively applied in the reconstruction of finger defects beyond PIP joint. Its advantages include a simple dissection, single-stage reconstruction, and preservation of digital artery and nerve. The donor site can be primarily closed if the flap width is less than 3 cm. Multiple subcutaneous heparin injection is a preferred solution in cases where venous congestion occurs in the flap.