母指指尖部皮膚欠損に対する母指橈側固有掌側指動脈を血管茎とした逆行性指動脈皮弁の3例

抄録

　We treated three cases of thumb tip defects with distal phalangeal exposure using a reverse homodigital flap based on the radial proper digital artery of the thumb. Preoperative ultrasonography confirmed the presence and patency of both the radial and ulnar proper digital arteries. The flap was designed along the radial midaxial line of the thumb, centered on the metacarpophalangeal joint, with the pivot point at the interphalangeal joint. The radial digital nerve was identified and preserved, and retrograde arterial flow was confirmed intraoperatively before flap elevation. The donor site was primarily closed in all cases. Complete flap survival was achieved in one case. Transient distal vascular compromise occurred in one case, and partial distal flap necrosis occurred in another; both cases healed with conservative treatment. No deep infection or osteomyelitis developed. Mild postoperative numbness was observed in all cases; however, it did not interfere with activities of daily living or return to work. This flap may represent a useful reconstructive option for thumb tip defects because it uses local thumb tissue and avoids donor-site morbidity in other digits. However, careful patient selection and flap design are essential because the flap relies on retrograde blood flow.