Progress of Proprioceptive Training in the Treatment of Traumatic Shoulder Instability

Investigating the Effect of Elevation and Sex-Based Differences on Shoulder Proprioceptive Accuracy

Background

Evaluating shoulder proprioception provides functional data that supplement imaging for the diagnosis/rehabilitation of rotator cuff injuries. There is a need for a system capable of establishing normal ranges for proprioceptive accuracy in healthy shoulders during unrestricted 3-dimensional motion.

Purpose

To conduct passive joint position sense (JPS) testing in men and women with no history of shoulder injury using a novel testing system, identifying differences in proprioceptive accuracy based on sex, shoulder elevation, and crossbody position.

Study Design

Controlled laboratory study.

Methods

We recruited 20 (10 male and 10 female) healthy participants aged between 18 and 25 years for JPS testing. Participants used a single wrist-worn sensor, and our primary outcome was errors in position matching (first guiding a participant's dominant arm from a neutral starting position to a target position and then having participants independently return from the start position to the same target) across 12 targets comprised of all possible combinations of shoulder elevation angles (EAs) (30°, 60°, 90°, and 120°) and crossbody angles (CAs) (0°, 45°, and 90°). A linear mixed model was employed to evaluate sex- and position-based differences in JPS accuracy.

Results

Position-matching accuracy increased in both males and females as target EAs increased from 30° to 120° (P < .001). The greatest EA position-matching accuracy in both sexes was observed at EAs of 90° and 120° (P < .0001). A change in the direction of error was observed in both males and females as target EAs increased from 90° to 120°, transitioning from positive (overshooting) to negative (undershooting) error (P < .005). A sex-based difference was observed at EAs of 60°, 90°, and 120° in the 90° CA plane, where females exhibited more negative CA matching error compared with males (P < .01).

Conclusion

Proprioceptive accuracy increased in both sexes at higher shoulder elevations. In the 90° CA plane, females demonstrated greater CA undershoot than males.

Clinical Relevance

While magnetic resonance imaging and ultrasound are effective tools for determining the size/age of rotator cuff tears, they do not provide functional prognostic insight for pain or mobility. Proprioceptive testing, as a functional metric based on free shoulder motion, may assist in clinically characterizing a patient's shoulder injury and rehabilitative success at multiple time points.

Retracted: Progress of Proprioceptive Training in the Treatment of Traumatic Shoulder Instability

[This retracts the article DOI: 10.1155/2022/1429375.].