Treatment of thumb soft-tissue defects using a bipedicle island flap of the index finger: anatomical basis and clinical application.

PURPOSE: Reconstruction of the thumb with exposure of bone and tendon is challenging. We designed a bipedicle island flap from the dorsum of the index finger to repair thumb defects. One pedicle includes the radial proper palmar digital artery (PDA) of the index finger, another pedicle includes the first dorsal metacarpal artery (FDMA). The aim of the study was to investigate the anatomical basis and clinical application of this flap. METHODS: Eleven fresh cadaver hands were dissected, the FDMA and the radial proper PDA were exposed. Their origin, distribution and diameter in different locations, especially in the dorsum of the proximal phalanx of the index finger, were examined. Ten patients (11 hands) underwent thumb reconstruction using this flap. During follow-up, the flap survival and hand function were evaluated. RESULTS: The origin of the FDMA in three cadaver hands was abnormal. The FDMA was mainly distributed in the proximal area of the dorsum of the proximal phalanx. The radial proper PDA of the index finger formed one constant dorsal branch, mainly distributing in the middle and distal area of the dorsum of the proximal phalanx. All flaps survived. At follow-up, the span of the first web and the range of motion of the thumbs and index fingers reached more than 94 % of the contralateral finger. All patients were satisfied with the hand function according to the Michigan Hand Outcomes Questionnaire (MHQ). CONCLUSIONS: The bipedicle island flap has two arterial systems to provide sufficient blood supply. This technique provides another option for thumb reconstruction when a large supercharged FDMA island flap needs to be designed, or when there is an additional injury to the radial side of the dorsum of the hand or if there are anatomical variations of the FDMA, or if damage to the FDMA occurs during surgery.

[The location of the superficial peroneal nerve in the leg and its relation to the surgical approach of the fibula].

OBJECTIVE: To localize the superficial peroneal nerve in surface of the leg and to provide a safety surgical approach to the fibula. METHODS: Sixty-six adult legs preserved by 4% formaldehyde solution were studied involving 42 male and 24 female with the average age of 69 years old ranging from 37 to 88 years. There were 35 cases in left and 31 in right. According to the common lateral surgical approach to the fibula, the superficial peroneal nerve and its branches were dissected in 66 embalmed leg-ankle-foot specimens. The specimens were observed and measured. RESULTS: The superficial peroneal nerve branched from the common peroneal nerve near the anterolateral aspect of the neck of the fibula, transversing through the muscle, deep fascia and superficial fascia. In 12 cases of specimens, superficial fibular nerve extended to the foot with no branches, in 50 cases of specimens it branched out into two before piercing the deep fascia, in the rest 4 cases of specimens, it branched out into two before piercing the muscle. CONCLUSION: To avoid injuring the superficial peroneal nerve, the surgical approach to the 2/3 upper part of the fibula is at posterior crural septum, to the 1/3 lower part of the fibula is at anterior crural septum.