Variations of Pronator Teres(PT) Muscle: A Morphological investigation

The muscles of shoulder girdle and elbow act together to position the hand accurately for manipulative functions. The superior extremity of man has undergone various modifications during evolution one of which is the lateral rotation of forelimbs at joints with pectoral girdle. The aim of the present study was to study the variations of Pronator teres(PT) muscle. The study of Pronator teres muscle is important because of its close relation to the median nerve. The present study was done on 60 upper limbs (56 Males and 4 Females) of embalmed adult human cadavers obtained from Deptt of Anatomy, Govt. Medical College Patiala. The humeral head of PT was found in all the cases, while Ulnar head was present in 52(86.7%) cases. The Humeral head was muscular in all the cases. The Ulnar origin was muscular in 15 cases (28.84%), tendinous in 7 cases(13.46%) & mixed in 30 cases (57.7%). In 2 (3%) cases there was double humeral head and the median nerve was passing between them. In 3 cases (5%) there was high origin of humeral head of Pronator teres from medial intermuscular septum. Anatomy instructors and health professionals should be aware of the common variations in muscles and tendons of the forearm, not only for their academic interest but also for their clinical and functional implications. The information of innervation pattern of median nerve to Pronator teres is of significant importance in understanding the different presentation of Pronator teres syndrome and its differentiation from other clinical conditions.