Sonographic evaluation of the extensor carpi ulnaris in asymptomatic tennis players.

OBJECTIVE

To determine the prevalence of structural abnormalities and instability affecting the extensor carpi ulnaris (ECU) tendons of asymptomatic recreational tennis players by the use of high-resolution ultrasonography.

DESIGN

Cross-sectional observational study.

SETTING

Academic sports medicine center.

PARTICIPANTS

Twenty-six asymptomatic, recreational male and female tennis players.

METHODS

A single, experienced operator completed bilateral static and dynamic ultrasound examinations of the ECU tendons of 26 asymptomatic, long-term, recreational tennis players ages 26-61 years (11 male, 15 female, average 24.4 ± 14.2 years of tennis participation). Tendons were evaluated for tendinosis and tearing, tendon sheath effusion and tenosynovitis, and instability via a standardized scanning protocol and predetermined diagnostic criteria.

MAIN OUTCOME MEASUREMENTS

The prevalence of static structural ECU tendon abnormalities (eg, tendinosis, tenosynovitis, tears) and dynamic ECU instability (eg, subluxation, dislocation).

RESULTS

Thirty-nine of 52 wrists (75%) demonstrated static ECU tendon abnormalities, the most common finding being a partial-thickness tear located just distal to the ulnar groove. Overall, 92% (24/26) of players exhibited tendinosis or tearing in at least one wrist. Dynamic ECU instability was detected in 42% of wrists (22/52) and 91% (20/22) of the time manifested as subluxation. Only 2 ECU tendon dislocations were observed, both occurring in the same individual. Overall, 73% (19/26) of players exhibited ECU instability in at least one wrist. There was no relationship between static and dynamic ECU tendon abnormalities within the methodological limits of the investigation. Complete ECU tearing, tendon sheath effusion, tenosynovitis, and static dislocation were not seen in any wrist.

CONCLUSION

Sonographic evidence of ECU tendinosis, partial-thickness tearing, full-thickness tearing, and subluxation can be seen in long-term, asymptomatic, recreational tennis players, whereas tendon sheath effusions, tenosynovitis, and tendon dislocation are uncommon. Further research is warranted to determine the clinical significance of asymptomatic ECU tendon abnormalities among long-term tennis players at multiple skill levels.