Measuring Shoulder Abduction in a Healthy and Young Population: A Feasibility Study

Abstract: The ability to maintain an independent living at higher age is closely linked to the physical function of an individual. The evaluation of the upper limbs, including the muscular strength of the shoulder, elbow or wrist has received little attention, yet arms are used in most daily tasks. The upper extremity physical performancecan be measured in several ways but none of them has the recognition to be theprimary method. The aim of this experimental study is to test the new devicedeveloped by Erik Almgren and assess whether this can be a valid tool to reliablyassess abduction shoulder strength. Fourteen healthy young subjects participated in this study. After placing in the left wrist the new device, they performed three types of tests: Full Range of Motion, Static measurements and Dynamic measurements. Three trials were done in each test with a recovery of 30 seconds. The results of the study showed that the Static measurements were similar to the ones obtained in previous studies in the past for both angles and force. For the first time, the study includes dynamic measurements of the moment of the shoulderjoint. Peak dynamic moments were found to be on average 6.43 N·m ± 1.00 N·mfor the females and 7.90 N·m ±2.33 N·m. This value is 6% lower than the test population’s average maximum static moments- result which in accordance withthe inverse relationship between force and velocity. The feasibility of this new device to be used outside a biomechanics lab has been proved, however, further research needs to be done in order to validate angles and measurements of the subjects.