Lower extremity return to sport testing: A systematic review.

Researchers wanted to figure out which tests actually work best when athletes are ready to come back to sport after a lower extremity injury. They searched through over 19,000 studies and picked 114 that looked at return-to-sport testing for things like knee, hip, and ankle injuries. What they found is striking: the research is heavily skewed toward knee injuries, especially ACL reconstruction, which made up 82% of all the studies they reviewed.

Even though there's mountains of research on ACL injuries and testing, nobody has settled on a standard set of criteria that all clinicians agree on for clearing someone to return to sport. The most common test used across studies was isokinetic dynamometry, a machine that measures muscle strength, but that popularity doesn't mean we've figured out what actually predicts safe return. The authors suggest their findings can guide future research toward developing better, more validated testing frameworks that clinicians can rely on.

If you're recovering from a sports injury to your knee, hip, or ankle and wondering when you'll be cleared to play again, you're asking exactly the right question. The honest truth is that clinicians don't yet have a single agreed-upon playbook for deciding when you're truly ready.

Right now, whether your physical therapist uses strength testing, movement screens, or a combination of tests can vary quite a bit. This doesn't mean your care is wrong, just that the field is still working toward more consistency and better science.

What this review tells us is that we need more research on hip and ankle injuries especially, since most studies focus on knees. The good news is that researchers are paying attention to this gap, and future guidelines will likely give your clinician clearer tools to make that return-to-sport decision with more confidence.

This is a summary of research, not medical advice. Talk to your own healthcare provider about anything affecting your care.

This systematic review highlights a significant knowledge gap we're working with in clinical practice. We're operating with an enormous amount of ACL literature but no standardized clearance criteria, which means each of us may be using different test batteries and thresholds with our athletes.

The prevalence of isokinetic dynamometry in the literature doesn't necessarily validate it as superior for predicting re-injury risk, just that it's been studied frequently. What's notable is the relative scarcity of research on hip and ankle return-to-sport testing, so if you're managing those injuries, you're often adapting frameworks from knee research or relying on clinical judgment with less evidence behind you.

The authors offer a potential roadmap by suggesting test batteries could serve as a foundation for future validation studies, but we're not at the point where we can confidently say which combination of tests best predicts safe return. For now, this paper tells us to be thoughtful about our battery selection and honest with athletes that we're still refining our approach to this decision.