Continued Significant Effect of Physical Training as Treatment for Overuse Injury: 8- to 12-Year Outcome of a Randomized Clinical Trial

Holmich P, Nyvold P, Larsen K. Am J Sports Med. 2011 39:2447. Epub 2011 Aug 3.

Physical therapy is a very common and effective treatment for musculoskeletal disorders; however, very little is known about the long-term effects of these treatments. The purpose of this follow-up trial was to revisit the original subjects of a randomized controlled trial studying the impact of a training program on adductor-related groin pain and test whether the effects were still statistically significant 8 to 12 years later. In the original study, 59 participants were randomized to receive either active treatment which involved strength training of the adductor, abdominal, and low back muscles combined with coordination and balance exercises, or passive treatment which involved manual therapy, electrotherapy and stretching. Of those subjects in the original study, 23 (79%) of those in the active-treatment group had an excellent outcome versus 4 (13%) of those in the passive-treatment group (p=0.001). The outcomes were assessed by the following criteria: (1) no pain at palpation of the adductor tendon and insertion points and no groin pain during resisted adduction, (2) no groin pain during or after athletic activity in the same sport and (3) return to the same sport and at the same level without groin pain. If all 3 measures were met, the result was labeled excellent; if 2 measures were met, the result was labeled good, if 1 measure was met the result was labeled fair and if no measures were met, the result was poor. Forty-seven (80%) of the original 59 subjects agreed to participate in the follow up study which consisted of a questionnaire based on a personal interview with a physician blinded to the original treatment group and an examination by the same physician using the identical protocol to the one used in the original study. During the follow-up period, most of the athletes had reduced their athletic level; however, this did not differ between the 2 treatment groups. Using similar outcome criteria as the original trial, the follow-up trial demonstrated 12 (50%) of athletes in the active-treatment group had an excellent result compared with 5 (22%) of the passive-treatment group (p=0.047). The association was even stronger in the subgroup of soccer players tested where 11 (55%) of athletes in the active-treatment group had an excellent result compared with 3 (16%) in the passive-treatment group.

This is an exciting study, because it suggests that an active training program can be used both as a treatment for acute pain and as a prevention strategy for future groin pain in athletes. However, given the long follow up period, there are many potential confounding factors when considering the authors’ conclusions. It is difficult, if not impossible, to compare return to sport at the same level following an acute injury versus after 8 to 12 years. The authors try to accommodate this by requiring return to sport in the follow-up study at the same or one level below the original level. This study implies that an active training program can make a difference in the long run, but it is unclear why this would be the case. The authors do not assess whether the athletes in the active treatment group continued any of the exercises shown to them during the training session in the years to follow as is commonly recommended after “graduation” from a physical therapy program. It is also unclear whether or not any of the athletes had recurrence of their groin symptoms during the follow-up period that may have resolved by the time the data were assessed. In general, though, this study suggests that a supervised core program and muscle-specific strengthening can have a beneficial impact on the treatment of chronic, overuse injuries both in present athletic endeavors and perhaps in the future as well. In your experience, can the proper rehabilitation program prevent future groin pain recurrences?

Written by: Hallie Labrador, MD and Peter C. Vitanzo, MD
Reviewed by:  Stephen Thomas

Hölmich P, Nyvold P, & Larsen K (2011). Continued significant effect of physical training as treatment for overuse injury: 8- to 12-year outcome of a randomized clinical trial. The American Journal of Sports Medicine, 39 (11), 2447-51 PMID: 21813441