What 'cleared to play' actually means — and what it doesn't

Historically, return to sport decisions were made on time: six weeks post-surgery, three months from injury. Time tells you something about tissue healing — it tells you nothing about whether the athlete is physically or psychologically ready to perform.

The 2016 consensus statement from the First World Congress in Sports Physical Therapy, led by Clare Ardern and colleagues, formalised a criteria-based approach. Return to sport should be guided by the athlete meeting specific benchmarks in strength, movement quality, sport-specific performance, and psychological readiness — not a calendar date.

For lower limb injuries — particularly ACL reconstruction — one of the most important criteria is the Limb Symmetry Index (LSI): the ratio of strength between the injured and non-injured limb, expressed as a percentage.

Grindem and colleagues found that for every 1% increase in quadriceps strength symmetry above a 90% LSI threshold, ACL re-injury risk dropped by approximately 3%. Patients who passed full return-to-sport criteria had an 84% lower re-injury rate than those who returned without meeting them.

That's not a minor detail. That's the difference between a sustainable return and a second injury.

Physical criteria are measurable. Psychological readiness is harder to quantify but equally important. Fear of re-injury after ACL reconstruction is extremely common, and athletes who return before they feel psychologically ready have higher re-injury rates than those who feel confident and prepared.

There are validated tools for measuring this — the ACL-RSI (Return to Sport after Injury scale) is one. A score below 77 has been associated with significantly higher re-injury risk.

In my clinic, I routinely include a conversation about readiness — not just "can your body do this?" but "do you trust your body to do this?"

One more thing: being cleared to return to sport is not the end of rehabilitation. It's the beginning of a graduated reintroduction to full competition load.

An athlete returning after 9 months of ACL rehab hasn't played live sport for 9 months. Their exposure to the unpredictability of actual competition — sudden changes of direction, contact, reactive demands — has been essentially zero. Loading needs to be managed carefully in the return phase to avoid the spike in training load that causes secondary injury.