Kinematical analysis of the elbow joint during push-up

Abstract

Muscle strength of upper extremities can be developed with regular pushup exercise training. However, performing pushup in wrong forearm rotation might lead to injuries as a result from excessive shear force acting on elbow joint. The objective of this investigation was to identity the elbow joint, right elbow angle and to develop a biomechanical model based on various data collected about movement involving this joint. The angle of the right elbow joint was investigated under various forearm rotations: neutaral position, internal position and external position during pushup. Subject was asked to perform pushup in various forearm rotations: neutral, 90° internal rotation, and 90° external rotation. The loading biomechanics of the elbow joint differed with various forearm rotations. It was noted that greater posterior and varus forces of the elbow are encountered with internal rotation of the hand position and, consequently, full forearm pronation. The elbow joint angles were significantly affected by forearm rotations.