UNILATERAL SHOULDER PAIN IS ASSOCIATED WITH ASYMMETRIES IN TENDON THICKNESS FOLLOWING MAXIMUM EXERTION IN AN ELITE WHEELCHAIR RUGBY ATHLETE: A CASE IN POINT TOWARDS INDIVIDUALIZED FEEDBACK

The purpose of this study was to describe changes in tendon thickness following maximum exertion in the symptomatic and asymptomatic shoulder of a highly trained wheelchair rugby athlete with tetraplegia. Tendon thickness of the biceps and supraspinatus on both sides were measured with ultrasound before any physical tests, after a treadmill test up to maximum exertion to define aerobic capacity, and after a 30s Wingate test to define anaerobic capacity. The athlete reported moderate to severe shoulder pain, quantified with the upper extremity pain symptom questionnaire (PSQ) on the left shoulder and no pain on the right shoulder. There was a meaningful reduction (i.e., \u3e 2 x SD) in biceps and supraspinatus tendon thickness after the physical tests at the asymptomatic shoulder with no meaningful changes at the symptomatic shoulder. Reduction in tendon thickness has been related to increased alignment of the collagen fibres or creep which is a typical response to tensile loading. While the symptomatic shoulder presented a higher peak power output, there was a significantly greater drop in maximum power output during the Wingate test. Subsequently, the greater decline in power output with fatigue in the symptomatic shoulder, may have increased loads on the asymptomatic shoulder and be related to the greater reduction in tendon thickness following exertion. This demonstrates the importance to monitor and reduce asymmetries to improve performance and prevent injury and pain