Hamstring and muscle injury: rehabilitation and return to play

ACL-specific consensus defining return to sport as a criteria-based continuum rather than a time point, and setting out testing and shared decision-making for clearance after ACL injury.

• Return to sport is a criteria-based continuum, return to participation, then return to sport, then return to performance, not a single date.
• Clearance should rest on objective testing (strength, hop, movement quality, psychological readiness), not time since surgery alone.
• The decision is shared between clinician and athlete, accounting for the sport's demands and the athlete's risk tolerance.

Our appraisal: Consensus via modified Delphi, so it sets the decision framework rather than validating any single test battery or cut-off. It is most useful as a reminder that a passed clock is not a passed knee; the specific thresholds still lack strong prospective validation.

Defines and operationalises 'return to sport' as a continuum (return to participation, return to sport, return to performance), with a shared decision-making framework (StARRT).

• Operationalises return to sport as a three-stage continuum applicable across injuries, not just ACL.
• Introduces the StARRT framework (Strategic Assessment of Risk and Risk Tolerance) for the return decision.
• Frames clearance as shared decision-making under uncertainty rather than a purely biological milestone.

Our appraisal: A foundational framework paper rather than an evidence synthesis. Its strength is a shared language for the return-to-sport decision: it tells you how to structure the decision, not what the pass criteria are, so pair it with injury-specific testing evidence.

MRI-based grading of muscle injury (0, 4, a/b/c) to guide prognosis and return to play.

• Grades muscle injury on MRI from 0 to 4 by extent of injury, with a site letter marking myofascial, muscle-tendon junction or intratendinous involvement.
• Designed to sharpen prognosis and inform return-to-play decisions beyond a simple strain label.
• Flags injuries involving the tendon (the 'c' subgroup) as tending towards longer recovery and higher re-injury risk.

Our appraisal: An expert-derived classification whose prognostic signals, especially around intratendinous injury, are supported by subsequent cohorts but not definitively validated, so it usefully structures expectations while return-to-play timelines remain individual rather than fixed by grade.

Consensus terminology and classification of muscle injuries in sport.

• Proposes standardised terminology for muscle injuries and distinguishes functional muscle disorders from structural muscle injuries.
• Sets out a classification running from overexertion-related and neuromuscular functional disorders through partial and complete structural tears and avulsions.
• Aims to improve diagnosis, prognosis and communication between clinicians rather than to prescribe treatment.

Our appraisal: Structured expert consensus, not a prospectively validated system, so it earns its place as a shared vocabulary rather than as proof of prognosis; the functional-disorder categories in particular have limited demonstrated inter-rater reliability, so use it to communicate clearly, not to promise timelines.