Early muscular training and immobilization in external rotation could reduce the recurrence rate in first-time shoulder dislocators among young rugby athletes

Background: Among rugby players, anterior shoulder dislocation is challenging to treat during the in-season period. It often leads to recurrent shoulder instability and requires prolonged rest post-surgery. No studies have determined the effectiveness of immobilization, early muscle strength training, or both in preventing reinjury in this population. Thus, the present study aimed to determine the impact of treatment outcomes between different immobilization methods and early muscle strength training in the conservative treatment of first-time anterior shoulder dislocation among young rugby players.

Methods: Rugby players under 23 years of age who chose conservative treatment for first-time anterior shoulder dislocation were included. The recurrence rate and recurrence-free period in a season and 2 years after return to sport (RTS) were retrospectively investigated for each immobilization method. The subjects were classified into three groups based on the immobilization method used: IIR group (incomplete immobilization in internal rotation was advised), iER group (strength training was started after 3-4 weeks of immobilization in external rotation [ER]), and iER+T group (early muscle strength training was combined immediately after the start of ER immobilization). All groups were allowed to RTS 8 weeks after injury or later. The endpoint was defined as a dislocation episode or the subjective feeling of shoulder subluxation, to a degree where the player could no longer continue to play the rest of the season.

Results: Thirty-four shoulders of 34 patients (31 males and three females; median age at injury: 17 [range: 15-22] years) were included (IIR group, 8 shoulders; iER group, 8 shoulders; and iER+T group 18 shoulders). The recurrence rates during the first season after RTS were 100%, 87.5%, and 55.6% in the IIR, iER, and iER+T groups, respectively, with statistically significant difference between groups (p = .037). Compared with the IIR and iER groups, the iER+T group showed a longer survival curve with significant difference in the transition of each curve for the treatment success rate (p = .045). In the IIR, iER, and iER+T groups, approximately 0%, 11.7%, and 50.0% of patients were able to continue to play for more than half of the remaining season without any recurrence of instability, and the overall probability of recurrence in 2 years was estimated to be 100%, 100%, and 81.7%, respectively.

Conclusion: The combination of immobilization in ER and early muscle strength training may be an effective treatment for anterior shoulder dislocation during the in-season period.