The proximal ulnar perforator flap (PUPF) for hand digital reconstruction: an anatomical study.

Degloving injuries of the fingers represent a reconstructive challenge. Even if poorly described in literature, the proximal ulnar perforator flap (PUPF), based on perforator of the anterior ulnar recurrent artery or directly on a perforator branch of the ulnar artery, meets the requested criteria for the ideal coverage. We performed a cadaveric study in order to clarify the anatomical basis and vascularization of the PUPF flap. Eight injected upper limb specimens were dissected for this study: perforators were followed down to their origin and classified in terms of number, length, diameters and distances between their emergence and specific pre-determined landmarks as the medial humeral epicondyle. At least one ulnar perforator in the proximal third of the forearm was identified in all the specimens. In 50% of the upper limbs, the perforator branch came directly from the ulnar artery, while in the 87.5% a perforator branch came from the anterior recurrent ulnar artery; in 3 out of 8 cases both perforator branches were described. Mean lengths of the perforator branch were 57.9 mm and 44.3 mm, respectively and the mean diameters measured at their origin were 0.99 mm and 1.17 mm respectively. Our data illustrate the consistency of at least one perforator branch from the proximal third of the ulnar artery, most commonly coming from the anterior recurrent ulnar artery. Considering our results, the PUPF could be a good alternative to the classical free flaps for the resurfacing of the finger defects.

Thumb Reconstruction With Thin Proximal Ulnar Perforator Free Flap.

Soft tissue defects of the thumb with exposure of tendons, periosteum, or neurovascular bundles require a complex reconstruction aimed at restoring both skin coverage and the essential function of pinching and manipulation. When large defects are involved, a free tissue transfer is indicated. The proximal ulnar perforator flap represents an interesting solution without the drawbacks of other more widespread free flaps. This report describes the case of a patient with a squamous cell carcinoma of the thumb that required circumferential resection of the soft tissue of the distal phalanx and the interphalangeal joint. The exposed structures were covered with pliable and texture-matching skin harvested from the proximal volar forearm and based on the proximal ulnar perforator. After 12-month follow-up, the patient was satisfied with the aesthetic outcome. Donor-site morbidity was minimal and no functional impairment in daily-life activities was reported. Even though a skilled microsurgical technique is required for the dissection of the perforator, its constant vascular anatomy and the low risk of damage to the main neurovascular bundle should make this flap reliable for the majority of hand surgeons.