Medial Arm Perforator Flap

, Shimin Chang², Jian Lin³ and Dajiang Song¹

(1)

Department of Orthopedic Surgery, Changzheng Hospital Second Military Medical University, Shanghai, China

(2)

Department of Orthopedic Surgery, Yangpu Hospital Tongji University School of Medicine, Shanghai, China

(3)

Department of Microsurgery, Xinhu Hospital Shanghai Jiao Tong University, Shanghai, China

The reverse medial arm island flap is a local fasciocutaneous flap based on the recurrent ulnar artery [1].

The medial intermuscular septum is a very thick structure which feels like a tough cord. The brachial artery and median nerve run hugging the septum anteriorly, while the ulnar nerve does so posteriorly. These structures are identified and preserved while raising the flap [2–4].

9.1 Vascular Anatomy

The brachia artery is the continuation of the axillary artery beyond the teres major. The artery courses in the intermuscular septum between the biceps and the triceps (Fig. 9.1).

Fig. 9.1

Vascular anatomy of the medial arm flap

The profunda artery is a musculocutaneous artery that is usually the first branch off the brachial. It arises 2–3 cm beyond the teres major and passes posteriorly between the humerus and the triceps to accompany the radial nerve. The branches from the profunda brachii supply the triceps and then perforate into the skin. Small cutaneous branches perforate the muscular fascia at 2 to 3 cm intervals, to supply the skin of the posterior two-thirds of the arm.

The superior ulnar collateral artery is an axial cutaneous vessel that arises 4–6 cm beyond the pectoralis major and courses distally through the subcutaneous tissue to enter the medial arm skin 6–12 cm beyond the pectoralis. The arterial diameter is from 0.8 to 1.5 mm. In 60 % of dissections this artery originates from the profunda artery, and in 20 % it originates directly from the brachial artery. In the other 20 % there is a double system with a direct cutaneous vessel exiting from both the brachial artery and the profunda artery. In this latter situation the vessel size is inadequate for free flap transfer but can be used for local or distant pedicle flaps.

The biceps musculocutaneous artery arises 6–8 cm distal to the pectoral muscle. After penetrating the biceps muscle, two or three major perforating vessels vascularize the anterior arm skin. The size of these vessels is variable.

The inferior ulnar collateral artery is an axial cutaneous artery that arises 5–10 cm from the elbow and may form collaterals either around the elbow or with the superior ulnar collateral artery. In 6 out of 16 dissections, a 0.4–0.6 mm direct cutaneous artery supplied the skin of the distal third of the arm.