By: Dr. Maddie Dickman (PT, DPT, CSCS)
If you’re recovering from a knee injury, you might be wondering at what point you’ll be able to return to a normal level of sporting or physical activity. You may feel ready, but how can you know for certain if you can safely return to activity without risking re-injury?
In this blog, we’re telling you everything you need to know about return to sport testing for a knee injury so you can hit the field or court with confidence and peace of mind!
What is Return to Sport Testing?
“Return to sport testing” refers to a series of assessments designed to gather both objective and subjective data to determine if an athlete has sufficiently recovered to begin reintegrating into their sport.
The specific tests included in return to sport assessments can vary between clinics and doctor’s offices, but they typically involve exercises such as:
- Single-leg jumping
- Range of motion checks
- Girth measurements of the leg
- Single-leg strength testing
The criteria for passing these tests also differ slightly between clinics, with some requiring a Limb Symmetry Index (LSI) of over 95%, while others only require over 90%.
Return to sport testing is crucial for ensuring that an athlete is truly ready to return to the field after a knee injury. Although these tests are most often associated with ACL injuries, they are valuable for assessing readiness after any type of knee injury to make sure the leg is fully prepared for the demands of sport.
If your current treatment plan does not include a return to sport test with a passing score requirement, we strongly recommend visiting a clinic that offers monthly testing to track your progress, such as our licensed physical therapists at Herlong Sports Physical Therapy.
Why is Return to Sport Testing Helpful?
Return to sport testing allows your clinician to directly compare your injured leg with your uninjured leg, providing specific measurements and a percentage that reflects how well your injured leg is performing. This information is crucial for your Doctor of Physical Therapy to determine how close you are to safely returning to your sport. Based on these results, your physical therapist can guide you on when to gradually start participating in drills at practice and advise you on what activities you should avoid to stay safe.
At HSPT, we’ve conducted extensive research as a team and developed a specialized test that evaluates the key muscle and joint functions of the knee. Our testing also simulates the sport-specific forces your knee will need to generate or endure to prevent future injuries. These tests have proven to be highly effective in assessing athletes’ readiness to return to play and are a valuable tool for helping patients understand their progress in rehab and how close they are to being fully recovered.
What Does Return to Sport Testing Involve?
The following is an overview of a return to sport test we’ve developed specifically at Herlong Sports Physical Therapy, drawing on both research and our experience. While return to sport testing is essential for a safe and effective return to athletic activity, not all clinics offer thorough or sufficiently challenging assessments. It’s crucial to choose a clinic that regularly monitors your progress, adjusts your treatment as needed, and fully challenges you to ensure you are 100% rehabbed before returning to play. This description provides a baseline understanding of our test. There are many detailed steps we take to ensure consistency and accuracy in the testing process, but these specifics are not included here for brevity and readability.
1. Range of Motion Tests
We will assess how much you can bend and straighten both of your knees to see how close they are to being perfectly symmetrical. We will also evaluate the smoothness of these movements, checking for any pain or stiffness.
Our goal at this stage is to achieve full, easy, and pain-free motion in your knee before you return to sport.
2. Girth of the Leg Measurements
For this test, we will take measurements at specific points around your calf, knee, and thigh to compare the muscle mass of your injured leg to your uninjured leg.
The goal of this test is to achieve nearly identical girth measurements between the legs, with a difference of less than 0.25 cm, if any at all.
3. Hop Testing
Our athletes then complete a series of four different hops to assess how well they can generate and control a single-leg jump. We’ll evaluate both the distance they can jump and their single-leg stability, overall landing mechanics, and their ability to produce and absorb force. The four single-leg tests include the single-leg hop, triple hop, crossover (zigzag) hop, and the 6-meter timed hop.
Each of these tests includes a practice trial followed by three attempts. We always test the uninjured leg first, followed by the injured leg, using the same guidelines. Specific criteria must be met for the jump to be considered valid, particularly regarding the landing.
For each leg, we take the average of the three attempts, then calculate a percentage by dividing the injured leg’s average by the uninjured leg’s average. This percentage shows how the injured leg is performing compared to the uninjured leg, which is our baseline at 100%. Athletes should reach over 95% before returning to full sport participation.
4. Strength Testing
Next, our athletes will undergo single-leg strength testing using a Tindeq device, which precisely measures the amount of force their leg can generate.
We start by testing the uninjured leg, performing knee extensions over three trials. We then conduct the same test on the injured leg to compare the results.
Next, we test the uninjured leg by performing knee flexion (hamstring curl) over three trials, followed by the same test on the injured leg. See the image below for reference.
Finally, we calculate the average peak force for each leg based on the three trials. We then determine a percentage by dividing the injured leg’s average by the uninjured leg’s average. The athlete should achieve over 95% of the uninjured leg’s strength before returning to full sport.
5. Review
The final and most crucial part of our return to sport test is making sure the athlete fully understands their current status in the rehab process. We want them to know how close they are to returning to sport, what activities they can and cannot do in practice, and what adjustments or continuations are needed to ensure they succeed in testing and perform well in their sport.
What Else is Required Before Return to Sport?
Athletes are challenged in various ways during each session at HSPT. If we identify other deficits during treatment, we will address those as well. While most issues are detected through our testing, there may still be areas for improvement in other parts of the body that, if unaddressed, could increase the risk of future injuries, such as core strength and control.
This testing is a valuable tool, but it’s not the sole focus or ultimate goal for our patients. We aim not only for the athlete to pass the test and return to their sport but also to ensure they are in a condition to perform successfully and at a high level once they do.
Why Should I Choose Herlong Sports Physical Therapy for Knee Rehabilitation?
At Herlong Sports Physical Therapy, we have meticulously designed a return-to-sport testing battery to challenge our athletes, provide valuable numerical data, identify any deficits or weaknesses, and facilitate clear communication with our patients about their rehab progress.
We adhere to extensive guidelines to ensure consistency in our testing process across clinicians. Once patients can perform the required components, we conduct these tests every 30 days to monitor progress and adjust treatment plans promptly if needed.
Our goal at HSPT is to meet the demands of our athletes. Through our effective treatment methods and rigorous testing, we ensure that athletes return to their sport not only safely but with a fully rehabilitated, challenged, and tested leg, and with both their body and mind ready to perform at their best.