Background Waterpolo consists of a combination of swimming and throwing with close contact between players. The shoulder is the most frequently injured joint, with a combination of rotator cuff tear and tendinopathy, long head biceps tendinopathy, superior labral lesions and shoulder impingement. This unique combination is a challenge for the clinician who must determine which of these shoulder pathologies is responsible for the onset of pain and the best strategy to rehabilitate the joint and prevent recurrence.

Aim The aim of this study was to estimate with ultrasound the frequency and characteristics of shoulder injuries in waterpolo players competing in different leagues.

Methods Forty-two players from two clubs in the premier and second Italian league were enrolled in the study. Standard and dynamic shoulder ultrasound scans were performed on all athletes.

Results Ultrasound investigation showed that almost all players had injuries of the shoulders; only four players did not show any shoulder modification. Thirteen athletes who had shoulder pain during the ultrasound examination showed subacromion deltoid bursitis and/or long head biceps tendinitis. No statistically significant differences in the frequency and characteristics of shoulder modifications or injuries were detected between players of the premier or second league.

Conclusion Shoulder injuries are very common in waterpolo players and comprise a peculiar and complex combination of rotator cuff tendinopathy and tears, long head biceps tendinopathy, impingement, subacromion deltoid bursitis and superior labral lesions. The use of ultrasound has been shown to be of considerable help in highlighting the modifications of the shoulder structures at an early asymptomatic stage. The ability to perform real-time scanning at the poolside makes ultrasound a useful tool in the rapid management and regular follow-up of shoulder modifications in everyday practice in sport medicine.