The Cutaneous Branch of the Deep Palmar Artery and Blood Supply to the Proximal Hypothenar Skin: An Anatomic Research Oriented to Flap Design.

Background: The distal half of the hypothenar eminence (HE) skin vascularization has been extensively investigated. Different flaps have been described based on these arteries. Similarly, the vascularization of the proximal half of HE has also been investigated, although to a lesser extent. The aim of this paper is to determine, in a cadaver sample, the anatomy of the hypothenar cutaneous branches in their proximal half. Methods: In all, 20 adult, red-colored-latex-injected hands were studied. Dissections were performed with a 4X to 10X magnification. Cutaneous branches in the proximal half of the HE were found. Their variants were studied, and they were classified into different types according to their relationships. Results: A cutaneous branch of the deep palmar artery (CBDPA) was identified. It was located in the subcutaneous cellular tissue thickness in the proximal half of the HE. Moreover, it presented 3 anatomical variants, classified according to its relationships with the superficial ulnar nerve branch (SUN). Type 1 variant: the CBDPA and the PDA ran in front of the SUN (60% of cases). Type 2: the CBDPA and the DPA ran behind the SUN (30% of cases). Type 3: the CBDPA ran in front of the SUN while the DPA ran behind it (10% of cases). Conclusion: There is a CBDPA which is the HE proximal half main cutaneous branch. Although it presented several variants, its existence is constant, making it possible to use it as pedicle for proximal hypothenar flaps.

The Proximal Fasciocutaneous Hypothenar Flap Based on the Cutaneous Branch of the Deep Palmar Artery: A Case Report.

The abductor digiti quinti flap for thumb hypoplasia has been used in its muscular variant as musculocutaneous flap. Several authors have reported myocutaneous branches in the proximal hypothenar region which would vascularize the skin segment covering the hypothenar muscles. Nevertheless, the presence of a cutaneous branch deep palmar artery (CBDPA) vascularizing the proximal hypothenar territory and possibly responsible for the proximal hypothenar cutaneous vascularization was reported. In this paper, a fasciocutaneous hypothenar flap was designed, based on the CBDPA, transposed to the wrist anterior region for the treatment of a post burn contracture which was limiting the wrist extension. Its viability was assessed. The flap had a lozenge-shaped design from the cutaneous fold of the wrist to the fifth metacarpophalangeal joint over the abductor digiti quinti muscle. It was dissected in the fasciocutaneous plane to a width of 20 mm. The adipose tissue zone 10 mm distal to the pisiform was preserved, as well as the ulnar nerve sensory branch crossing the flap longitudinally. The flap was transposed to the anterior fold of the wrist. Neither the flap nor the donor site underwent complications. The patient improved wrist extension without referring any discomfort. Sensitivity was 8 mm 2 months after surgery compared to 6 mm within the preoperative period. In conclusion, it is possible to develop a proximal fasciocutaneous hypothenar flap based on CBDPA involving the proximal and distal hypothenar territory.