Purpose of the study: Surgical reconstruction procedures using the gracilus myocutaneous flap may be compromised if partial or total necrosis of the skin cover develops. The purpose of this study was to describe the anatomic blood supply to the gracilus muscle and the corresponding skin cover in an attempt to better understand the arterial afferences to the skin and define the safest topography for a transferable zone of skin.

Material and methods: We dissected the thighs of human adult cadavers to detail the vascular bundles feeding the gracilus muscle.

Selective injections of methylene blue were used in the main gracilus pedicle; the area of skin colored was then measured (greatest and smallest diameter) for computation of the surface area using an imaging software.

Results: Preliminary results of nine dissections showed that the main blood supply of the gracilus muscle arose from the deep femoral artery (n=8 dissections) or the common femoral artery (n=1 dissection) then penetrated the muscle 90.55 mm below the pubis with a mean diameter of 1.32 mm. The muscle was fed by one to four accessory arteries. The skin cover was stained in all cases, the area involved lying over the proximal and mid thirds of the muscle. The surface area was irregular, the mean length being 127.5 mm and the mean width 91.66 mm. The computed surface area was 88.08 cm² on average (range 58–120.95 cm²). Each muscle had two to six perforating vessels issuing from the opposite side of the main pedicle and comprised within a 48 mm long segment before dividing at the subcutaneous level. A mathematical model correlated the skin surface area to the number of perforating arteries.

Discussion and conclusion: Our findings suggest it would be possible to determine the surface area of skin transferable with a gracilus muscle flap based on high-frequency duplex-Doppler assessment of the number and position of the perforating arising from the muscle and feeding the skin surface. The linear distribution of the surfaces measured as a function of the number of perforating arteries suggests that more reliable conditions for gracilus myocutaneous flap harvesting could be proposed to minimize the risk of cutaneous necrosis.

Purpose: The purpose of this study was to establish the map of the motor branches of the median and ulnar nerves of the forearm and to count the Martin-Gruber anastomoses. Knowledge of anatomic variability would be useful for hyponeurotisation surgery of the spastic hand. Variations in the antebrachial emergence of the six motor branches of the medial nerve and the three motor branches of the ulnar nerve were studied.

Material and methods: This study was conducted on twenty anatomic specimens obtained from five men and five women. We measured the length of the forearm and identified the origin of each motor branch of the medial and ulnar nerves using a horizontal line between the meidal and lateral epicondyles as the reference line.

Results: Mean length of the forearm was 26.93±2.6 cm. Unlike the origin of the superior and inferior pronator teres nerves, and the palmaris longus, flexor carpi radialis, and flexor digitorum superficialis nerves which were very variable (coefficient of variation 49%–113%), the origin of the anterior interosseous nerve of the forearm (CV=39%) and its branches, and the flexor pollicis longus nerve and the flexor digitorum profondus nerves (CV =23% and 29% respectively) were much more regular. The superior and inferior origins of the flexor carpi ulnaris nerve were variable (CV = 157 and 22%) while the origin of the nerves for the deep flexor of the IV and V fingers showed a better coefficient of variation (13%). We observed four Martin-Gruber anastomoses (20%).

Conclusion: This study demonstrated the wide anatomic variability of the medial and ulnar nerves both interin-dividually and intraindividually. Emergence of certain nerve branches appeared to be more regular, particularly the lower group of the median nerve and the anterior interosseous nerve of the forearm. It was however impossible to identify two groups exhibiting a statistically significantly greater frequency for the median nerve. The anatomic variations of the ulnar nerve were less pronounced. The inconsistency of the inferior flexor carpi ulnaris is noteworthy.