The success of return-to-sport following anterior shoulder instability treatments

Your weekly research review

Contents of Research Review

1. Background & Objective
2. What They Did
3. What They Found
4. Practical Takeaways
5. Reviewer’s Comments
6. About the Reviewer
7. Comments

Original study

Shanley, E., Thigpen, C., Brooks, J., Hawkins, R. J., Momaya, A., Kwapisz, A., … & Tokish, J. M. (2019). Return to sport as an outcome measure for shoulder instability: surprising findings in nonoperative management in a high school athlete population. The American journal of sports medicine, 47(5), 1062-1067.

Click here for abstract

Background & Objective

Anterior shoulder instability among youth athletes accounts for nearly a quarter of all shoulder injuries. The current options for treating an episode of shoulder instability includes either operative or non-operative management. Often, young athletes who experience a shoulder instability episode decide to try to finish out the remainder of their season, and then undergo surgical intervention at the end of the season. This study aimed to determine if there was a difference in an athlete’s ability to return-to-sport (RTS) after an episode of shoulder instability between athletes who underwent surgery and those who chose not to have surgery and used non-operative management instead.

What They Did

This study followed twenty high schools in South Carolina for four years and included any athlete who was part of a highschool sports team and experienced a traumatic shoulder instability episode during a game or practice that resulted in time-loss from sport.

The first instability episode was considered the initial encounter. The primary outcome measure was successful RTS, which was defined as the ability to return to the same sport and position, and the ability to complete the following season without an injury recurrence causing time-loss from sport. When an athlete experienced a shoulder instability episode, they were first evaluated by their high-school’s Athletic Trainer. Following this, the athlete’s injury was reviewed by a sports medicine physician or orthopaedic surgeon who confirmed the direction and classification of the instability and prescribed the plan of care (surgical or non-surgical intervention). The surgeon’s recommendation was followed, and then either after surgery or as part of the non-operative management, the athlete participated in exercise-based therapy by either a Physical Therapist, Athletic Trainer, or both. An athlete was cleared to RTS when they met set criteria (painless activity, symmetrical range of motion, 67% external to internal rotation ratio, apprehension test, and body weight loading during functional upper-extremity movement without apprehension).

What They Found

Overall, there were 129 athletes included in this study; 32 of them underwent surgical intervention, and 97 were managed non-operatively. Of the athletes who were managed nonoperatively:

82 (85%) were able to successfully RTS.

Of the 32 athletes who underwent surgical intervention, 23 (72%) were able to successfully RTS.

During the follow-up period, 8 athletes suffered a recurrence of shoulder instability, leading to timeloss from sport, 6 of these from the non-operative group (6.2%), and 2 from the operative group (6.3%).

Overall, 88% of 129 athletes included in this study were able to successfully RTS.

Furthermore, athletes who sustained a dislocation were nearly 3x more likely to fail RTS than those who experienced a subluxation. Superior outcomes were noted in athletes who had a subluxation and were treated non-operatively.

Practical Takeaways

In this study, there was no difference in RTS outcomes for athletes who were managed operatively vs. nonoperatively for anterior shoulder instability. There was also a similar recurrence rate of about 6% in both groups. Of the 15 patients in the non-operative group who failed to successfully RTS, 11 ended up having surgery with an 82% successful RTS after surgical intervention. This tells us that it may be beneficial to initially prescribe a nonoperative plan of care and then perform stabilisation surgery on athletes who fail to RTS.

Other studies have looked at successful outcomes after non-operatively managed anterior shoulder instability using a primary outcome measure of recurrence (see HERE), and found a 44% success rate in athletes who were managed non-operatively (as opposed to the 85% reported in this study). Since the primary outcome measure in the current study was the ability to RTS and complete a subsequent season without a recurrence causing a time-loss from sport, it may be that the athletes in this study did experience recurrences in instability but were able to cope with them and continue playing in spite of them.

Reviewer’s Comments

“This study utilised a follow-up period of one season after the initial encounter. Indeed, there may be subsequent episodes of instability in high-school athletes beyond the follow-up period of this study. Take, for example, a high school freshman who experiences an episode of shoulder instability. According to the metrics utilised in this study, as long as they are able to play in their sophomore season, then they would be considered to have had a successful outcome. What if that same athlete then goes on to have a recurrence in their junior season which causes them to miss most of the season and, therefore, not be seen by college scouts? Or what if they don’t sustain another instability episode, but is consistently fearful of reinjury and has feelings of instability that cause them to have decreased performance and, therefore, never reaches their potential playing ability?
We can hardly consider these to be successful outcomes, although in this study, an athlete such as this hypothetical example would have been part of the “successful” group. As stated above, it is therefore favourable to make sure that the athlete plays a key role in determining what a successful outcome looks like to them.”

How do you approach shoulder instability rehabilitation? Let us know below…