Decision to Return to Sport Participation After Anterior Cruciate Ligament Reconstruction, Part II: Self-Reported and Functional Performance Outcomes.
Werner JL, Burland JP, Mattacola CG, Toonstra J, English RA, Howard JS. J Athl Train. 2018 [ahead of print]
Take Home Message: Athletes that do not return to a cutting/landing sport reported lower scores on patient-reported outcome measures; however, performed similarly on functional measures compared with athletes that returned to sport post anterior cruciate ligament (ACL) reconstruction. Hence, physical performance alone may be less than ideal for returning an athlete to play post surgery.
An anterior cruciate ligament (ACL) reconstruction is commonly used to help patients regain function and return to sport. However, despite having good function many patients fail to return to pre-injury levels of sport. It is unclear if commonly used functional measurements may explain differences between those who return to sport or not and if there may be other factors that are important (for example, a patient’s perception of their knee function). To bridge this gap the authors evaluated athletes that returned to sport (7 males, 11 females, ~23 years of age) and those that did not return (5 males, 7 females, ~26 years of age) to compare functional test scores and patient-reported outcome scores between groups prior to surgery and at the time of the study. The patient-reported outcome measures were Tegner Activity Scale, Cartilage Injury Standard Evaluation From-2000, International Knee Documentation Committee Subjective Knee Evaluation Form [IKDC], Marx Activity Scale, Knee Injury and Osteoarthritis Outcome Score [KOOS]). The functional tests were strength and muscular endurance, Star Excursion Balance Test (SEBT), 3 single-legged hop tests, isokinetic knee-flexor and knee extension strength, and a step-down-to-fatigue test. The authors calculated a limb symmetry index based on a ratio of the mean performance values for the functional performance tests from each leg. All athletes had a history of primary unilateral ACL reconstruction (no difference between surgery type between groups) and were at least 1 year post-operation (~4 years post). The authors defined return-to-sport as an athlete who returned to at least 1 of the cutting or landing sports that they participated in before an ACL injury. The authors found no differences between groups for limb symmetry indexes, which typically exceeded 85% at the post-operative exam. The non-return athletes reported lower scores on the IKDC and the symptoms portion of the KOOS at the post-operative exam.
The authors found that non-return athletes conveyed lower patient-reported outcome measures despite performing similarly on the functional measures. Both groups obtained functional limb symmetry index scores that exceeded 85% (the minimally clinically important difference). Hence, regardless of whether an athlete returned to competitive sport or not within one year of an ACL reconstruction they were likely to have restored physical performance. However, the non-return group reported worse scores on patient-reported outcome measures, which exceeded the minimally clinically important difference. This is important to note since on average the assessment was 4 years’ post reconstruction; therefore, patient-reported outcome measures may be more meaningful than physical measures for returning an athlete to sport. Alternatively, there may be more effective ways to assess function than with a limb symmetry index, which may overestimate the functional performance of an injured limb. It would be interesting to see a longer follow-up (5-10 years down the line) and identify risks of osteoarthritis because these patient-reported outcome measures could be predictive of poor long-term outcomes. This information is helpful to ensure we are properly restoring function without increasing risk of long-term problems. Currently, medical professionals should use various functional and sport-specific measures, as well as patient-reported outcomes to measure the patient’s self-perceived physical function. This may help clinicians address how an athlete feels they are doing and identify potential changes in priorities or expectations in returning to sport.
Questions for Discussion: What criteria do you use to determine if an athlete is ready to return to play after an ACL reconstruction? Do you use patient-reported outcome measures?