Why Testing Matters
Research shows that athletes who pass comprehensive return-to-sport testing have significantly lower re-injury rates. Time since surgery alone is not sufficient - you need objective evidence that your knee is ready.
- Reduces re-injury risk: Passing all criteria is associated with 84% lower re-injury risk
- Identifies deficits: Reveals weaknesses that need more work
- Builds confidence: Objective proof you're ready
- Informs decision-making: Data-driven return, not guesswork
Standard Test Battery
1. Single Leg Hop for Distance
Stand on one leg, hop as far as possible, and stick the landing. Best of 3 attempts on each leg.
Passing: Limb Symmetry Index (LSI) ≥ 90%
2. Triple Hop for Distance
Three consecutive single-leg hops for maximum distance. Land on the same leg for all three hops.
Passing: LSI ≥ 90%
3. Crossover Hop for Distance
Three consecutive single-leg hops crossing over a center line. Tests lateral stability while hopping forward.
Passing: LSI ≥ 90%
4. 6-Meter Timed Hop
Single-leg hop for speed over 6 meters. Tests ability to hop quickly and maintain control.
Passing: LSI ≥ 90%
5. Quadriceps Strength Testing
Isokinetic or isometric quad strength testing comparing surgical to non-surgical leg.
Passing: LSI ≥ 90% (some protocols require ≥ 85%)
6. Hamstring Strength Testing
Similar strength testing for hamstrings. Especially important for hamstring graft patients.
Passing: LSI ≥ 90%
7. ACL-RSI Questionnaire
Psychological readiness assessment measuring confidence and fear of re-injury.
Passing: Score ≥ 56/100 (higher = more ready)
Calculating LSI
LSI = (Surgical leg / Non-surgical leg) x 100. For example: If surgical leg hops 180cm and non-surgical hops 200cm: (180/200) x 100 = 90% LSI.
Quality Criteria
Beyond distance/time, observe quality of movement during all hop tests:
- No knee valgus: Knee doesn't collapse inward on landing
- Controlled landing: Stick the landing without excessive wobble
- Equal effort: Similar effort and confidence on both legs
- No compensation: Trunk doesn't shift excessively