The applied anatomy and clinical application were described in this paper. The blood supply of this flap was based on the second dorsal metacarpal artery. It gave some advantages of as easy of application, safe and reliable. Since November 1990, we had successfully used six such flaps in covering the soft tissue defects of the hand.
Objective To provide the anatomic bases for clinical application of the second dorsal metacarpal artery(SDMA) island flap with double pivot points. Methods The origin,branches and distribution of the recurrent cutaneous branch of the SDMA were observed in 30 adult fresh cadaver specimens, which were illustrated with special dye.Eighteen cases of skin defets of the thumb were repaired with the SDMA island flap. The defect locations were the dorsal part in 11 cases and palmar part in 7 cases, including 3 cases of defect in association with long pollical extensor defect and 2 cases of defect in association with dorsal skin defect of proximal finger. The flap area ranged from 2 cm×3 cmto 3 cm×5 cm. Results The appearance of therecurrent cutaneous branch of the SDMA was observed in all cases(100%), which originated 0.5±0.2 cm distant from the distal intersectiones between the SDMA and the index extensor and disappeared 1.2±0.5 cm distant from the proximal metacarpophalangeal joint. The branches of 1.7±0.7 were seen with a longitudinal fan-like distributionforward proximal part on the deep surface of the dorsal superficial vein. The exradius and the length of the recurrent cutaneous branch of the SDMA were 0.3±0.1 mm and 6.5±0.8 mm, respectively. The transplanted flaps survived in all cases and 16 cases were followed up for 8-14 months. The colour and appearance of the skin were satisfactory. The two-point discriminations were 0.9 mm in 3 cases by bridging digital nerve and 1.1 mm in 9 cases by anastomosing dorsal digital nerve; while the two-point discrimination was 13-15 mm in 4 cases without anastomosing nerve. Conclusion The origin,branches and distribution of the recurrent cutaneous branch of the SDMA is constant, which provide a potentially longer pedicle and increase the possibility to rotate the flap and also avoid the donor skin defect of rotation of the flap.
Objective To explore the effect of the first dorsal metacarpal artery-based pedicle dictyo-pattern sublobe flaps in repairing irregular wounds on thumbs and index fingers. Methods From December 2006 to March 2009, 15 patients with irregular wounds on thumbs and index fingers were treated, including 11 males and 4 femals, with an average age of 31 years (range, 18-48 years). Of them, 6 cases of hyperplastic scar of postburn had a 2-25 years course of disease (7.5 years onaverage) and 9 cases of machine injury had a 14-30 days course of disease (20 days on average). In 8 thumb wounds on palmaris, there were 3 cases of rhomboid wounds, 1 case of C-shape wound, and 4 cases of irregular wounds; the area of wounds ranged from 4.5 cm × 3.0 cm to 5.5 cm × 4.5 cm and wounds were treated by the first dorsal metacarpal artery-based proximate pedicle dictyo-pattern sublobe flaps (5 cm × 3 cm to 6 cm × 5 cm). In 7 index fingers wounds on dorsi-fingers, there were 3 cases of 2-wounds, 4 cases of irregular wounds; the area of wounds ranged from 1.0 cm × 0.5 cm to 2.2 cm × 2.0 cm and wounds were treated by the first dorsal metacarpal artery-based distal pedicle dictyo-pattern sublobe flaps (1.2 cm × 0.5 cm to 3.0 cm × 2.2 cm). The donor sites were covered with skin grafts or sutured directly. Results All of the flaps survived completely, the wound of recipient site healed at stage I. The free skin graft on donor site survived completely, the wound of donor site healed at stage I. All cases were followed up for 6-12 months (9 months on average). There was good appearance of flaps. The two point discrimination was 5-7 mm for the proximate pedicle flaps and 9-10 mm for the distal pedicle flaps. The thumbs had digital opposition, opposition function, the index fingers had no dysfunction. According to Hand Surgery Association Society of Chinese Medical Association Society standard for the part function evaluation trial-use of upper l imb, the results of the total active movement were excellent in 14 cases, and good in 1 case. The l ine-scar was existed at donor site of the case of direct suture, the function of thumb web had no dysfunction. Conclusion The first dorsal metacarpal artery-based pedicle dictyo-pattern sublobe flaps can repair the irregular wounds on thumbs and index fingers. It has rel iable blood supply and simple operation.