Recurrence rates after primary traumatic shoulder dislocation are distinctly high. Whether the early external immobilization (ER) is better than the internal immobilization (IR) is still controversial.

To perform a systematic review of randomized clinical trials (RCTs) that assessed the ability of external immobilization to reduce the recurrence in patients with primary anterior shoulder instability.

As with the original review, we used the search strategies recommended by the Cochrane Back Review Group for the identification of RCTs. Thirteen RCTs were included in the systematic review, and 11 studies were included in the quantitative synthesis.

A total of 1042 participants with primary shoulder dislocation were involved. The meta-analysis of 11 trials revealed that ER therapy leading to less recurrence rates than participants treated with IR therapy (RR=0.55; 95%CI: 0.36 to 0.82; Z=2.88; p=0.004), and less complications (RR=0.6; 95%CI: 0.39 to 0.92; Z=2.33; p=0.02) from the 5 independent trials. The meta-analysis of three trials revealed that there are not statistically significant in compliance rate (RR=1.08; 95%CI: 0.89 to 1.29; Z=0.78; p=0.44). The GRADE level of evidence is high for adverse events, but moderate for recurrence rate and Compliance rate. The Begg test showed that no significant publication bias was detected (p=0.062).

This meta-analysis suggests that external immobilization is recommended to reduce the recurrence rate and prevent complications.

II, low-powered systematic review and meta-analysis (systematic review, meta-analysis).