Higher signal/noise quotient value of subscapularis tendon on the throwing side in elite female water polo athletes: a cross-sectional study.

Objective: This study innovatively employed magnetic resonance imaging in conjunction with isokinetic strength testing to examine the differences between no throwing shoulder and throwing shoulder injuries in elite female water polo players.

Methods: This study examined the radiographic findings as well as the internal and external rotation strengths of 16 elite female water polo players. A 3.0 T magnetic resonance imaging scanner was utilized to qualitatively and quantitatively assess the tendon structure of the shoulder. Concurrently, isokinetic strength testing of the shoulder Joint at 90° abduction was conducted in isokinetic concentric mode at speeds of 60°/s × 5 and 180°/s × 10. The peak torque/body weight (PT/BW) from multiple sets of movements was recorded.

Results: All the athletes completed the tests, and magnetic resonance imaging did not reveal any full-thickness tears of the rotator cuff in either the throwing shoulder or the non-throwing shoulder. However, the supraspinatus tendon, subscapularis tendon, and long head of the biceps brachii presented varying degrees of signal abnormality. Further analysis revealed that the signal/noise quotient of the subscapularis tendon in the throwing shoulder was significantly greater than that in the no-throwing shoulder (p < 0.05), whereas no significant differences were detected between the two shoulders for the other tendons. Additionally, the PT/BW of the throwing shoulder for external rotation was less than that of the no-throwing shoulder at an angular velocity of 180°/s (p < 0.05).

Conclusions: Elite female water polo athletes experience the same injuries as no-throwing shoulders do in their throwing shoulders, but the subscapularis tendon on the throwing side has a higher signal/noise quotient value.