Brief summary, from the abstract
In young athletes, returning to knee-strenuous sport sooner than 9 months after ACL reconstruction was linked to roughly a 7-fold higher rate of a second ACL injury, while passing symmetry tests for muscle function or quadriceps strength was not protective.
- Athletes who returned before 9 months had a much higher rate of a second ACL injury (hazard ratio 6.7; 95% CI 2.6 to 16.7; P<.001).
- A higher preinjury activity level (Tegner score) also raised the risk (hazard ratio 2.1; 95% CI 1.2 to 3.6; P<.01).
- Symmetrical muscle function and symmetrical quadriceps strength at return showed no association with reinjury.
- Prospective cohort of 159 athletes (mean age 21.5 years, 50% female), representing only 32% of the initial sample, so selection and observational design limit the strength of the evidence.
Clinically assessing this area? See the knee special tests.