Prevalence and anatomical pattern of the median artery among adult black Kenyans
Knowledge of the anatomy of median arteries is important in the diagnosis and management of carpal tunnel and pronator teres syndromes, reconstructive surgery in the forearm, minimizing inadvertent vascular injury as well as in limiting operative complications due to unexpected bleeding. The anatomical pattern displays ethnic differences but there are few studies on black Africans. This study therefore sought to describe the anatomy of median arteries in an adult black Kenyan population. A total of sixty two (62) upper limbs from thirty one (31) formalin-fixed cadavers were studied at the Department of Human Anatomy, University of Nairobi, Kenya. The prevalence, origin, types, relationship with median nerves and termination were determined. Median arteries were observed in 37 (59.7%) cases. Of these, the palmar type comprised 12 (32.4%) and antebrachial type 25 (67.6%) cases. It occurred bilaterally in 14 (45.2%) cases. The most common origin was the common interosseous artery (21; 56.8%) followed by anterior interosseous (13; 35.1%) and ulnar 3 (8.1%) arteries. The artery pierced the median nerve in 7 (18.9%) cases. The palmar type terminated by uniting with the ulnar artery to form a median-ulnar type of superficial palmar arterial arch in 8 (21.6%) cases and directly gave rise to the first, second and third common digital arteries in 4 (10.8%). In conclusion, the median artery occurs in nearly 60% of the population, much higher than in prevailing literature reports. Prevalence of the palmar type of median arteries and that of median arteries piercing median nerves are also higher than in other populations. Accordingly, presence of median artery and consequently other vascular and median nerve variations should be considered in the differential diagnosis of forearm entrapment neuropathies and due caution taken during forearm surgical procedures. We recommend preoperative ultrasound evaluation of the forearm and hand vascular system.
Keywords: Median artery, origin, prevalence, median nerve, Kenyan