3 Step Criteria-Based Return to Sport After Acute Groin Injury

Hip and groin injuries are common in change of direction sports. Hockey in particular, has a high percentage of hip and groin issues. Worner et al (2019) have shown that >50% of hockey players suffer from hip and groin issues over the course of a season and those who reported worse long term hip and groin function tended to have worse hip and groin function at the beginning of the new season. Now these issues can be attributed to many hip pathologies, such as abdominal wall tears and intra-articular pathologies like cam or pincer deformities and labrum tears which commonly present as groin pain. True adductor injuries in hockey can be attributed to the high demand on the adductors during the skating stride. The adductors have shown to have two activation peaks in skating, one at foot down and the other at the end of push-off. Tyler et al found that those with a weaker adductor:abductor ratio below 80% were more susceptible to groin injuries, suggesting that strength is a key factor in groin injuries. One of the other large factors that increases the risk of adductor injury is a previous adductor injury. So in order to avoid recurring adductor injuries we must provide a complete rehab and return to sport program. 

A 3-step return to sport after acute groin injury 

Serner et al (2020) recently published a paper on a criteria-based rehab protocol for return to sport after an acute adductor injury, mainly in soccer/futsal players.  They followed a return to sport progression that consisted of 3 milestones: 1) clinically pain-free, 2) controlled sports training and 3) full team training. Once the athlete reached full team training, return to play was at the athlete and the team’s discretion. 

Over the course of 4 years, 75 athletes suffered from an acute adductor injury who were assessed and treated with an exercise–based protocol. At follow-up, 93% had returned to full team training. However, not everyone completed all the RTS milestones for various reasons, with 61 reaching clinical pain-free and 50 completing controlled sports training milestones. Regardless, the results showed that those with grade 0-2 strains (based on MRI) completed the RTS milestones in less than 4 weeks, taking significantly less time to reach each milestone than those with grade 3 injuries. Interestingly, they also found that those who reached clinically pain-free had a lower proportion of reinjury than those who didn’t but achieving milestone 2 (controlled team training) did not decrease the proportion of reinjuries. This suggests that reaching clinically pain-free before returning to sport is a good indicator of low reinjury risk. However, they did not compare this to injury severity. I would think that being clinically pain-free may be acceptable for less severe injuries, of which a large portion of the athletes had, but those with a more severe injury would benefit from achieving all 3 milestones.   

Exercise Loading Protocol 

One of the more interesting things with this paper was the exercise loading protocol they used for the rehab exercises. They used a combination of groin specific exercises, general lower body and sport-specific exercises, as well as progressive running and sport movements over a 4–phase program. The load progression used was what they called “pain-controlled repetition maximum” to load the tissue, where the athletes were encouraged to reach a minimum pain of 2/10 during exercises and if they weren’t, they were to increase the resistance. This is something I believe we are often very cautious, maybe too cautious and we end up underloading the tissues. Once the athlete had minimal pain (<2/10) at rest, during walking and full standing abduction AROM, they began this loading progression. The early loading, increased resistance into minimal pain in conjunction with early initiation of a running and sport movement program was thought to have been a factor in the fast return with a small number of reinjury.  

In addition to this loading protocol, they included exercises targeting other areas of the body. Although no specific exercises were given, they mention that there was a focus on the posterior chain. Often chronically poor position of the pelvis can add strain to the adductors. By adding an increased focus on the posterior chain, this could have improved pelvis position and control. Reducing the strain on the adductors could have had an impact on the low reinjury rate. 

Key Takeaways 

I know that the sample from this study is mainly soccer related athletes, but I think that here are a few key takeaways that could and probably should be applied to athletes from any sport to appropriately rehab adductor injuries and decrease the reinjury rate.  

1)We should follow a criteria-based rehab protocol. It’s just not enough to give stretches and strengthening for 4-6 weeks before allowing athletes to return to sport. We must objectively measure and test the athlete’s pain and ability in high intensity and fatigued situations.

2) LOAD. Simply, we need progressively overloading the tissues. There is evidence to suggest that loading into some pain and discomfort can be beneficial, and this study supports that as well. Early loading, running and sport specific movements with some but minimal discomfort while progressing to more advanced loading in the later stages could lead to a faster and safer return to sport.

3) We always need to be looking for the suboptimal. Although it is an adductor injury, if there is additional strain on the adductors coming from above or below, this will impede a successful recovery. Posterior chain and trunk work can help improve pelvis position and control which in turn can reduce unnecessary strain on the adductors.