Kinematics Study of Glenohumeral Joint at Different Arm Elevation Planes in Normal Chinese / 医用生物力学

ABSTRACT

Objective To investigate relative translations of the glenohumeral joint during abduction, scaption and forward flexion in normal Chinese, so as to provide references for diagnosis, treatment and follow-up of glenohumeral joint instability and subacromial impingement syndrome.Methods The biplanar fluoroscopy system combined with model-image registration technique were used to measure the humeral translation relative to the scapular in 13 healthy volunteers during abduction, scaption and forward flexion.Results The anterior-inferior glenohumeral translation during abduction, scaption and forward flexion was (4.0±1.3), (4.1±1.5),(4.8±1.9) mm, respectively. The superior-inferior glenohumeral translation was (3.0±1.0), (3.1±1.1), (3.3±1.5) mm, respectively. During the whole motion, there was a significant difference in superior-inferior translation at different arm elevation angles, while other significant differences were not found.Conclusions For normal Chinese, the humeral head was positioned posteriorly and superiorly on the glenoid. During forward flexion, the anterior-inferior and superior-inferior glenohumeral translation was the maxium. Therefore, in the process of clinical diagnosis, treatment and follow-up, patients performing the forward flexion may obtain a better evaluation effect.