A Clinical Shoulder Proprioception Test Shows Good Reliability, and Decreased Shoulder Joint Position Sense Due to Local Fatigue in Handballers: A Repeated Measures Design
Abstract Background: Assessment of shoulder proprioception outside the laboratory in the absence of specialized equipment remains a challenge with field-based tests often lacking good reliability, validity and feasibility. This study aimed to enhance the knowledge base surrounding the assessment of shoulder proprioception and investigated the effect of fatigue on shoulder joint position sense (JPS) amongst amateur male handball players.Method: 27 healthy recreationally active participants and 13 amateur male handball players undertook two sessions of active JPS tests using laser pen technology and a calibrated 2-dimensional target to assess test-retest reliability. The active JPS test was then utilized on the subgroup of handball players who were subjected to five bouts of a repeated throwing task in order to investigate the effect of local fatigue on shoulder JPS. Results: The intraclass correlation coefficient for the active JPS test was 0.78 (95% CI = [0.57; 0.89]). Standard error of measurement between trials was 0.70° (range 0.57°-0.90°). For the throwing task, repeated measures analysis of variance revealed a significant interaction for arm x bout (F5=2.74, p=0.028) and a significant effect for arm (F1=5.85, p=0.034). Post hoc analysis showed a significant difference between throwing arm and non-throwing arm after throwing bout one (p=0.036), three (p=0.026) and four (p=0.041). Conclusion: Assessment of the active JPS test showed acceptable reliability and measurement error. Repeated throwing to fatigue decreased shoulder JPS in amateur male handball players which indicate validity of the test to identify reduced proprioception.