Bifid inverted palmaris longus muscle - a case report

A bifid inverted Palmaris longus muscle was identified during routine cadaveric dissection while teaching undergraduate students. The muscle belonged to the right forearm of a 54-year-old male cadaver, and had a tendinous origin from the medial epicondyle of the humerus. Distally the muscle passed superficial to flexor retinaculum and bifurcated into a muscular slip and a fascial slip. The muscular slip further descended down and became continuous with the hypothenar muscle and the fascial slip inserted into palmar aponeurosis. The total length of the inverted palmaris longus muscle till bifurcation was 28.0 cm. The length of the muscular slip of the insertion was 2.6 cm, and the length of the fascial slip of the insertion was 3.1cm. Such anatomic variation can lead to compression of the median and ulnar nerves.