Ernest Schilders, MD, et al
The Journal of Bone and Joint Surgery. October 2009. Vol. 91-A. No. 10. Pp. 2455-2460
Adductor enthesis is diagnosed through a combination of patient history, clinical tests, and MRIs. In this study, athletes were treated with a steroid injection combined with a numbing agent. The aim of this study was to compare recreational athletes with competitive athletes.
Not everyone with groin pain and positive muscle/tendon tests had a positive MRI for adductor enthesis. Those who did were put in one group. Those with positive muscle/tendon tests, but without obvious changes on MRI were placed in a second group. All were treated with the injection followed by a physical therapy rehab program.
Five minutes after the injection was given, the patients were re-evaluated using the three tendon tests: palpation, stretching, and resistance. Results were recorded and the tests were repeated at six weeks, six months, and one year later. In every case, the pain was relieved immediately.
One-third of the patients in group one had a recurrence of their groin pain during that first year. In group two, about one-third of the group had another bout of groin pain anywhere from two weeks to 19 weeks after the injection.
In comparing the results of the recreational athletes with the competitive athletes who had the same problem, same tests, and same treatment the MRI findings did predict results of injection. Patients with visible tendon enthesis damage were more likely to experience pain recurrence affecting their ability to play one year after the injection. Competitive athletes with a negative MRI who had the injection, got better and stayed pain free.
The authors summarized by saying that MRI findings do not predict treatment outcome for recreational athletes using steroid injection for adductor enthesis. Quite the opposite is true for competitive athletes whose MRI does predict the final results. There were two main differences that might account for these findings. One, the recreational athletes were older and had their groin pain longer. And two, because their lives did not depend on competing in their sport, they could rest during painful episodes.
The authors also noticed the recreational athletes with negative MRI and mild pain seemed to have the best results with a second injection when the symptoms came back.
Steroid injections aren’t routinely recommended for athletes with groin pain. Those who do not benefit from rest and/or physical therapy and who test positive for tendon pain with palpation, stretching, and resistance may be the best candidates for injection therapy.
