STUDIES NO THE BIOMECHANICALFOR ELBOW JOINT IN FOUR SPECIES OF PRIMATES

This paper carried out the comparative study of the morphology, biomechanic and electromyography(EMG) on the elbow joint for slow loris, rhesus monkey, black leaf-monkey and gibbon. The main conclusions were as follows: 1. The flexibility of articulatio cubiti was developed with the increasing function of forelimb. According to the results of EMG for flexors and extensors of forearm among four species, we believed that brachialis muscle played the most important role during flexion of forearm, but auxiliary functiary function was completed by brachio-radialis muscle and biceps brachialis muscle. 2. In rhesus monkey, the relative low magnitude of EMG of flexors and extensors in forearm and the evidently different morphologies of articulatio cubiti from that of other species were related to its movement of quadrupedalism and supporting stability of articulation. 3. The morphological and electromyographical similarities of musculoskeleton for elbow joint between leaf monkey and gibbon showed that there existed some similar functions relating to brachiation and flexible movement of forelimb. 4. The results of descriminat and univariance analysis implied that, the significant differences were appeared in flexors and extensors of elbow joint comparing to skeleton. The indices of the proximal origin of brachialis muscle, the insertion of brachioradialis muscle andthe proximal and distal origin of medial head of triceps brachialis muscle were the important factors to differentiate the four species of primates.