Determination of shoulder range of motion

Abstract

The shoulder joint is the most substantial part of the human anatomy necessary for individuals to carry out activities of daily living (ADL) such as drinking and combing. It provides high degree of manoeuvrability and numerous movements. However, the condition of shoulder joint differs from person to person. It was revealed in many studies that age and gender are two major factors affecting the condition of shoulder joint mobility. It was also reported that excluding external factor such as impact and accident, these two factors contribute to shoulder disorder and pathologies. Therefore, it is important to take the two factors into consideration when assessing one’s shoulder health. Clinically, the system of orthogonal planes enables clinicians to assess the function and health of a shoulder based on its range of motion (ROM). The orthogonal planes were used to describe the location of structures and direction of human bodily movements. However, the movements of humerus when performing ADL are not limited to these planes and thus, the system of orthogonal planes is inadequate in quantifying ADL movements. The globe system was introduced in recent years of study to evaluate kinematics of the shoulder joint and humerus movements at any position. This study proposed to represent the shoulder ROM in an open-loop globe model that allows simple and fast visual insight of an individual’s shoulder ROM. The objective of this study is to investigate the effect of gender on a globe model. The comparisons were made on the dominant shoulder ROM and ADL for both genders. A total of 13 males (Age 33.62 ± 15.17) and 15 females (Age 21.87 ± 1.13) with no history of shoulder injuries were recruited in this study. The subjects were tasked to perform 6 ADLs, 6 standard ROMs and one global ROM (GROM). This study revealed no statistical differences (p > 0.05) between genders (age range 21 to 29) for all the standard ROMs, ADLs and GROM except for internal rotation and washing middle back. The comparison of ROM can also be seen in a visual representation between genders on a globe model.