Importance of functional performance and psychological readiness for return to pre-injury level of sports 1 year after ACL reconstruction in competitive athletes

Key points

1. 01Two factors at 6 months independently predicted 1-year return to sport: single-leg hop symmetry and the ACL-RSI psychological readiness score.
2. 02Quadriceps strength, hamstring strength, and the IKDC score did not stay significant once hop and readiness were accounted for.
3. 03A single-leg hop below 81.3% of the uninjured leg flagged most athletes who would not return (sensitivity 0.891).
4. 04A psychological readiness score below 55 was a more specific warning sign (specificity 0.826).
5. 05These two quick tests can screen athletes at 6 months so rehab can target whoever falls short.

How it was conducted

Design

Prospective prognostic cohort study

Participants

124 competitive athletes (Tegner activity score over 7) after primary ACL reconstruction

Tests at 6 months

Quadriceps index, hamstrings index, single-leg hop, IKDC score, and ACL-RSI psychological readiness

Outcome

Self-reported return to pre-injury sport level at 1 year (return vs no return)

Analysis

Multivariate logistic regression plus ROC analysis to find optimal 6-month cut-offs

What they found

• At 1 year, 101 athletes returned to sport and 23 did not.
• Single-leg hop was an independent predictor (odds ratio 2.861 per 10-unit increase, P<0.001).
• ACL-RSI psychological readiness was an independent predictor (odds ratio 1.810 per 10-unit increase, P=0.001).
• Optimal single-leg hop cut-off was 81.3% (sensitivity 0.891, specificity 0.609).
• Optimal ACL-RSI cut-off was 55 points (sensitivity 0.693, specificity 0.826).
• Strength indices (quadriceps, hamstrings) and IKDC did not remain significant in the multivariate model.

Limitations

• Return to sport was self-reported at 1 year, which can be inaccurate.
• Only 23 athletes did not return, a small group for building a prediction model.
• Findings come from one cohort of competitive athletes, so the cut-offs may not transfer to recreational athletes or other settings.
• As an observational study it shows association, not proof that improving these scores causes more athletes to return.

Why it matters

For patients

If your 6-month hop test or confidence score is low, it is a signal to keep rehabbing rather than rush back, not a verdict that you will fail.

For clinicians

Add a single-leg hop test and the ACL-RSI to 6-month follow-up so athletes below roughly 81% hop or 55 readiness can be flagged for targeted work.

For readers

Confidence and functional hop ability matter as much as raw strength when judging readiness to return after ACL surgery.