Shoulder Proprioception: A Cross-Sectional Comparative Study on Handedness, Sex, and Direction of Movement

Objective: The shoulder joint plays a crucial role in upper limb function and mobility. A thorough examination of shoulder proprioception is essential for the early identification of at-risk shoulders, with the aim of eliminating the risk of shoulder instability and/or injury. This study aims to examine the changes in proprioception in the shoulder joint based on factors of sex, handedness, and movement direction. Material and Methods: A cross-sectional study was conducted with 60 healthy young adults (30 men, 30 women). Participants' active joint position senses (AJPS) were evaluated for shoulder internal rotation (IR) and external rotation (ER) using an isokinetic dynamometer. The Wilcoxon Signed-Rank Test and Mann-Whitney U Test were used to assess differences. Results: Statistical analyses revealed no significant differences in the AJPS of shoulder IR and ER movements between the sexes for both extremities (dominant IR: p=0.075, r=0.325, ER: p=0.459, r=0.135, and non-dominant IR: p=0.122, r=0.283, ER: p=0.476, r=0.130). Additionally, no differences were found in AJPS between the dominant and non-dominant extremities (IR: p=0.283, r=0.139, ve ER: p=0.306, r=0.132), as well as between IR and ER movements (dominant: p=0.102, r=0.211 and non-dominant: p=0.724, r=0.0.045). Conclusion: The study concludes that AJPS in the shoulder joint does not vary based on sex, handedness, or direction of movement. In addition, the AJPS values we found in our study may be used as a reference for clinical evaluations and may help to identify proprioceptive disorders. Additionally, our results can facilitate ensuring the homogeneity of participant groups concerning sex or handedness factors in scientific studies on shoulder proprioception. Keywords: Joints, proprioception, reference, upper extremity.