Dorsal Ulnar Artery Flap

The dorsal ulnar artery flap is usually indicated for covering the anterior side of the wrist, especially when there is a requirement for well-vascularized tissue to cover the medial nerve. The covering of the dorsal region of the wrist is restricted; thus, the flap is indicated when there are small defects, due to the length of the arterial pedicle which limits the arc of rotation of the flap. The authors described the rotation technique for the dorsal ulnar fasciocutaneous flap, conducted with five patients with extensive lesions in the dorsal region of the wrist or the hand.

A line is delineated between the pisiform bone and the medial epicondyle of the humerus which correspond to the medial flap. The ulnar artery, the dorsal cutaneous branch (5 cm from proximal to pisiform), and the ulnar border of the tendon of the flexor carpi ulnaris are delimited. Dissection begins in the flap apex raised with the fascia and the superficial vessels of the muscular body of the flexor carpi ulnaris from proximal to distal. The dissection extends to the visualization of the dorsal ulnar branch entry in the profound surface of the graft. This visualization can be unnecessary, if the dissection is interrupted 5 cm from proximal to pisiform. The pedicle can be swivelled up to 180° after tubing of the flap base, without involving blood supply. The dissection region is covered with skin graft, and a Penrose drain is placed under the graft. The hand is kept elevated for 5 days to facilitate the venous return. Another choice is to schedule the skin graft when pedicle disconnection occurs, in about 3 weeks, as part of the flap can return to the forearm.

A 57-year-old female underwent serious injury with tendon exposure (4 × 4 cm) in the dorsal region of the secondary left wrist, with chemotherapeutic extravasation (Epirrubicina). The authors attempted to use the method of rotation of the Chinese flap and the posterior interosseous flap. However, due to intense chemotherapeutic impregnation in the dorsal radial area of the forearm, there was destruction of the concomitant vessels, the radial artery, and the posterior intraosseous. Rotation of the dorsal ulnar flap with fasciocutaneous pedicle was therefore chosen. There was a satisfactory result, with the pedicle disconnected after 3 weeks.

A 50-year-old female, with a history of malignant mammary neoplasia, had undergone radiotherapy and chemotherapy. There was extravasation of the chemotherapeutic (Doxorrubicina), presenting features of compartment syndrome in the left hand. Fasciotomy and posterior debridement of the necrosed tissues was carried out. There was extensive injury (9 × 6 cm) and exposure of the extensor tendons. Cover with a dorsal ulnar artery flap (18 × 6 cm) was chosen, since there was impregnation by chemotherapeutic at the site. The donor site was partially closed and subsequently covered with skin graft.

A 52-year-old male was the victim of trauma in the right hand by an agricultural machine, with traumatic amputation of the fifth finger (to the level of the metacarpophalangeal rotation), comminuted fractures from the second to the fourth fingers, in addition to lesions of the soft tissue at the dorsal side of the hand. Subsequently, the second finger also underwent amputation. A dorsal ulnar flap (6 × 8 cm) was swivelled for covering the dorsal side of the hand.

A 21-year-old male was the victim of burning on the dorsal side, from the second to the fifth fingers of the left hand, extending from the metacarpophalangeal rotation up to the distal interphalangeal rotation. A dorsal ulnar flap (8 × 8 cm) was swivelled for coverage of the dorsal side of the fingers, forming a surgical syndactyly. Subsequently, the fingers were separated.

A 17-year-old male underwent trauma in the right hand with an agricultural machine, presenting with amputation of the third and the fifth fingers to the metacarpal level, and lesions in the soft tissue on the palmar and dorsal sides of the hand. The fourth finger was approximated to the second finger, and a dorsal ulnar artery flap of 14 × 9 cm was swivelled for covering the palmar and dorsal sides of the hand.

The dorsal ulnar artery flap was initially described for covering small defects on the palmar side of the wrist, especially in the medial nerve. Despite the limitation of the arc of rotation due to the short length of the pedicle, the dorsal ulnar flap can be used to cover defects on the dorsal side of the wrist and the ulnar border of the palmar region. As it is a simple dissection flap, it does not need extensive microsurgical experience to accomplish it. In the reported study, there was no tissue loss in the flap, although it was swivelled with a fasciocutaneous pedicle that needed skin graft to cover the donor area, almost always done after flap disconnection. It was concluded that the dorsal ulnar artery flap is one more choice for covering defects with bone exposure, and tendon or nerve lesions of the wrist and hand. The anatomic limits of the dissection should be respected due to the limitation of venous drainage.