ACL Return To Competition Insights

Table of Contents

  1. Time versus criteria
  2. Functional tests and thresholds
  3. Psychological readiness and re-injury risk factors
  4. Sport specific and consensus guidelines
  5. Emerging recommendations and gaps
  6. References
  7. One-Minute-Paper Topics

1 Time versus criteria

Return decisions historically relied on fixed postoperative timelines, but contemporary evidence and expert groups advocate adding objective criteria and delaying clearance for high-risk athletes. This section contrasts the prevailing time-based practice with validated criterion-based approaches and common recommended minimum timelines.

  • Historical practice: Time dominant criteria (used alone) were common in the literature, and many studies allowed unrestricted RTS before 9 months postoperatively [1].
  • Criterion-based model: The Delaware protocol emphasizes resolving clinical impairments, ≥90% LSI on quadriceps strength and multiple single-leg hop tests, patient-reported outcomes, and an appropriate healing time (generally ≥9 months) before full competition [2].
  • Practical recommendations: Several contemporary reviews and guideline syntheses recommend combining time with objective milestones (eg, strength, hop tests, PROs) and delaying RTS for high-level or pediatric athletes; some authors propose minimums of 8–9 months as part of a multifactorial clearance [3] [4].

References: time prevalence and early RTS findings [1]; Delaware objective criteria and ≥9 months recommendation [2]; guideline-level recommendations for delayed RTS and strengthening testing [3] [4].

2 Functional tests and thresholds

Functional testing is central to criterion-based clearance; common batteries include quadriceps strength, multiple hop tests, and movement-quality assessments, with limb symmetry index thresholds frequently used as pass criteria. Below is a concise comparison of common tests, reported thresholds, and typical clinical use.

Test domainTypical measuresCommon threshold or pass criterionEvidence source
Quadriceps strengthIsokinetic peak torque, max voluntary isometric/quadriceps force≥90% LSI or normalized torque benchmarks cited in test batteries[5] [2]
Hop testsSingle hop, triple hop, crossover hop, 6‑m timed hop≥90% LSI on all hop tests commonly required in batteries[2] [5]
Movement qualityLanding Error Scoring System (LESS), qualitative movement analysisLESS and movement-quality screening recommended as adjuncts; pass thresholds vary (eg, LESS ≤5 used in some protocols)[5]
Patient reported outcomesIKDC, KOS-ADLS, GRS, ACL‑RSIPRO thresholds (eg, KOS-ADLS ≥90%, ACL‑RSI cutoffs reported) often included alongside physical tests[2] [5]
Multi-test batteryCombination of strength, ≥2 dynamic tests, PROs, clinical examPassing multi-domain batteries (strength + ≥2 dynamic tests + psych readiness) reduces heterogeneity in outcomes and is commonly recommended[4] [5]
  • Implementation note Clinical programs commonly use a battery requiring ≥90% LSI for quadriceps and hop tests as a core pass criterion, supplemented by absence of effusion/full ROM and PROM thresholds [2] [5].
  • Limitations Although ≥90% LSI is widely used, current evidence does not prove that meeting these criteria guarantees protection from reinjury; test batteries frequently fail to predict safe RTS with high accuracy [1] [5].

Citations: test prevalence and thresholds [2] [5]; predictive validity limitations and recommendations for multi-test approaches [1] [5] [4].

3 Psychological readiness and re-injury risk factors

Psychological status and specific patient and exposure factors influence return outcomes and reinjury risk; contemporary recommendations incorporate validated psychological scales and identify modifiable and nonmodifiable risk factors. The section outlines validated psychological measures and evidence-backed risk correlates.

  • Psychological measures: ACL‑RSI and other patient-reported readiness scales are recommended components of RTS batteries and are often used with numeric cutoffs in test protocols [5] [6].
  • Key modifiable risk factors: strength asymmetry (LSI <90%), poor movement quality/fatigue responses, and early return (<8–9 months) are associated with higher reinjury risk and are targets for remediation [2] [7] [8].
  • Key nonmodifiable or contextual risk factors: younger age and female sex have been identified as contributors to higher reinjury rates in several reviews and pooled analyses [7] [4].
  • Clinical synthesis: Authors recommend assessing psychological readiness alongside physical tests and including interventions (eg, sport psychology, graded exposure) when scores indicate fear or low confidence [5] [6].

Evidence: psychological test inclusion and thresholds in batteries [5]; younger age and earlier RTS as risk factors in pediatric/adolescent cohorts [7]; movement quality, fatigue, and chronic load considerations as reinjury contributors [8]; modifying factors such as age and sex noted in systematic syntheses [4].

4 Sport specific and consensus guidelines

Sport demands, staged reintegration, and several society-level recommendations guide tailoring RTS pathways; recent consensus and expert frameworks recommend multi-domain, sport-specific progressions rather than a one-size-fits-all rule. This section summarizes sport-specific progressions, professional guidance, and emerging organizational recommendations.

  • Sport-specific progressions: Progressive on-field and on-ice reintegration phases are advocated (eg, Delaware staged progression from individual drills to full competition; on-ice 4‑phase hockey progression) with objective criteria to enter each phase [2] [9].
  • Team-sport and high-demand sport frameworks: Frameworks for team sports emphasize retraining high-intensity repeated actions, cutting, decelerations, and reactive skills with motor-learning principles and graduated complexity [10] [11].
  • Consensus and guideline highlights: Multiple contemporary reviews and guideline papers call for objective, criterion-based RTS testing integrated with shared decision-making and a biopsychosocial model; professional recommendations commonly include strength testing, ≥2 dynamic tests, psychological screening, and a delayed timeline (commonly ≥8–9 months) as core components [12] [3] [4] [13].
  • Practical implementation: Use sport-specific drills, progressive exposure to contact/opposition, and monitoring of chronic training load during late-stage rehab to restore sport readiness and reduce reinjury risk [9] [10] [11].

Cited sources include sport-specific progressions and on-ice protocol [9], team-sport progressive frameworks [10], and consensus-style recommendations and reviews urging multifactorial RTS approaches [12] [3] [4] [13].

5 Emerging recommendations and gaps

Emerging approaches expand testing beyond traditional strength/hop batteries toward biomechanics, fatigue and load metrics, imaging, and longitudinal monitoring; validation of these methods is ongoing. This section lists novel directions and the principal evidence gaps to inform future practice.

  • Novel assessment domains: movement-quality biomechanical analysis, fatigue testing, and explosive neuromuscular performance are proposed additions to better capture sport demands and re-injury mechanisms [8] [11].
  • Imaging and biomarkers: MRI-based graft assessment and other imaging tools have been suggested as potential adjuncts to inform tissue healing and readiness, but predictive utility remains investigational [14].
  • Service-delivery and decision models: Recommendations favor a layered, continuous evaluation model with repeated athletic assessments through rehabilitation, shared decision-making, and individualized, sport-specific reintegration plans rather than a single end-point test [13] [15].
  • Evidence gaps: Current batteries (including ≥90% LSI rules) lack proven predictive validity for reinjury prevention; high-quality prospective studies that test whether meeting combined, sport-specific criteria reduces second-injury rates are still needed [1] [5] [16].

Key emerging proposals come from late-stage rehabilitation reviews and commentaries that advocate expanding testing scopes and validating new metrics in prospective cohorts [8] [11] [14] [13].

References

[1]J. J. Capin and L. Snyder-Mackler, “Return-to-Play Criteria: The Delaware Experience,” pp. 127–137, Jan. 2018, doi: 10.1007/978-3-662-55713-6_10.

[2]B. S. Solie, L. V. Tollefson, C. P. Doney, J. O’keefe, W. Thompson, and R. F. LaPrade, “Return to the Pre-Injury Level of Sport after Anterior Cruciate Ligament Reconstruction: A Practical Review with Medical Recommendations,” International journal of sports medicine, Mar. 2024, doi: 10.1055/a-2270-3233.

[3]J.-P. Lorange, L. Senécal, P. Moisan, and M.-L. Nault, “Return to Sport After Pediatric Anterior Cruciate Ligament Reconstruction: A Systematic Review of the Criteria.,” American Journal of Sports Medicine, pp. 3635465231187039–3635465231187039, Feb. 2024, doi: 10.1177/03635465231187039.

[4]A. W. Brinlee, S. B. Dickenson, A. Hunter-Giordano, and L. Snyder-Mackler, “ACL Reconstruction Rehabilitation: Clinical Data, Biologic Healing, and Criterion-Based Milestones to Inform a Return-to-Sport Guideline”, doi: 10.1177/19417381211056873.

[5]R. Joreitz, A. D. Lynch, C. D. Harner, F. H. Fu, and J. J. Irrgang, “Criterion-Based Approach for Returning to Sport After ACL Reconstruction,” pp. 397–411, Jan. 2017, doi: 10.1007/978-3-319-32070-0_33.

[6]J. D. Harris et al., “Return to sport after ACL reconstruction.,” Orthopedics, vol. 37, no. 2, Feb. 2014, doi: 10.3928/01477447-20140124-10.

[7]Y. Kaplan and E. Witvrouw, “When Is It Safe to Return to Sport After ACL Reconstruction? Reviewing the Criteria.,” Sports Health: A Multidisciplinary Approach, vol. 11, no. 4, pp. 301–305, May 2019, doi: 10.1177/1941738119846502.

[8]J. J. Capin, W. Behrns, K. E. Thatcher, A. J. H. Arundale, A. H. Smith, and L. Snyder-Mackler, “On-Ice Return-to-Hockey Progression After Anterior Cruciate Ligament Reconstruction.,” Journal of Orthopaedic & Sports Physical Therapy, vol. 47, no. 5, pp. 324–333, Apr. 2017, doi: 10.2519/JOSPT.2017.7245.

[9]C. Unverzagt, E. Andreyo, and J. Tompkins, “ACL Return to Sport Testing: It’s Time to Step up Our Game.,” The International journal of sports physical therapy, vol. 16, no. 4, pp. 1169–1177, Aug. 2021, doi: 10.26603/001C.25463.

[10]A. Fort-Vanmeerhaeghe, J. Arboix-Alió, and A. M. Montalvo, “Return-to-sport following anterior cruciate ligament reconstruction in team sport athletes. Part II: Progressive framework,” vol. 57, no. 213, p. 100361, Jan. 2022, doi: 10.1016/J.APUNSM.2021.100361.

[11]M. Buckthorpe, “Optimising the Late-Stage Rehabilitation and Return-to-Sport Training and Testing Process After ACL Reconstruction,” Sports Medicine, vol. 49, no. 7, pp. 1043–1058, July 2019, doi: 10.1007/S40279-019-01102-Z.

[12]S. D. Barber-Westin and F. R. Noyes, “Objective criteria for return to athletics after anterior cruciate ligament reconstruction and subsequent reinjury rates: a systematic review,” The Physician and Sportsmedicine, vol. 39, no. 3, pp. 100–110, Sept. 2011, doi: 10.3810/PSM.2011.09.1926.

[13]S. Blee, “Anterior Cruciate Ligament Rehabilitation and Return to Play,” pp. 67–81, Jan. 2019, doi: 10.1016/B978-0-323-54839-7.00009-9.

[14]R. Turk et al., “Critical Criteria Recommendations: Return to Sport After ACL reconstruction requires evaluation of time after surgery of 8 months, >2 functional tests, psychological readiness, and quadriceps/hamstring strength.,” Arthroscopy, vol. 39, no. 3, pp. 790-801.e6, Oct. 2022, doi: 10.1016/j.arthro.2022.08.038.

[15]B. Dingenen and A. Gokeler, “Optimization of the Return-to-Sport Paradigm After Anterior Cruciate Ligament Reconstruction: A Critical Step Back to Move Forward.,” Sports Medicine, vol. 47, no. 8, pp. 1487–1500, Jan. 2017, doi: 10.1007/S40279-017-0674-6.

[16]C. Burgi et al., “Which criteria are used to clear patients to return to sport after primary ACL reconstruction? A scoping review,” British Journal of Sports Medicine, vol. 53, no. 18, pp. 1154–1161, Sept. 2019, doi: 10.1136/BJSPORTS-2018-099982.

One-Minute-Paper Topics

A One-Minute-Paper (OMP) is a short, focused prompt that students answer in ~60 seconds at the end of a session to consolidate learning, surface misconceptions, and provide formative feedback. When answering, be concise, specific, and use terminology from today’s session.

  1. Contrast the time-based and criterion-based models for ACL return-to-sport clearance: what are the main limitations of each?
  2. Describe the Delaware protocol’s core criteria for return-to-competition clearance, including the LSI threshold and minimum recommended timeframe.
  3. What are the four test domains in a comprehensive return-to-sport battery? Name one validated test per domain.
  4. Explain why ≥90% LSI on quadriceps strength and hop tests does not guarantee protection from reinjury, and what additional factors must be considered.
  5. What is the ACL-RSI scale, and what dimension of return-to-sport readiness does it specifically capture?
  6. Define the Landing Error Scoring System (LESS) and explain what it adds to a strength- and hop-test-based battery.
  7. Describe two modifiable risk factors for ACL reinjury that can be targeted in late-phase rehabilitation.
  8. Explain why younger athletes and female athletes show higher reinjury rates, referencing the evidence presented in the lecture.
  9. What role does sport psychology play in return-to-competition preparation, and which specific intervention was highlighted?
  10. Describe the concept of “shared decision-making” in return-to-sport clearance and identify the key stakeholders involved.
  11. Why should psychological readiness be assessed in parallel with physical test criteria rather than sequentially?
  12. Explain how a multi-test battery (strength + ≥2 dynamic tests + patient-reported outcomes) reduces outcome heterogeneity compared to single-domain testing.
  13. What is the rationale for a minimum of 8–9 months before unrestricted competition, even when all test criteria are met?
  14. Define “layered sport-specific reintegration” and describe how it differs from a simple stepwise return-to-play protocol.
  15. How would you advise a high-level athlete who has passed all objective criteria at 7 months but is eager to return to competition?
  16. What does current evidence say about the predictive validity of ≥90% LSI for safe return-to-sport, and what does this mean for clinical interpretation?
  17. Describe one scenario in which the KOS-ADLS or IKDC score would change a return-to-competition recommendation.
  18. Why is the combination of early return (<8–9 months) AND strength asymmetry (LSI <90%) considered particularly high-risk?
  19. Which finding from today’s lecture most changed your view of how return-to-competition decisions should be made, and why?
  20. Formulate one question about the evidence base for ACL return-to-competition criteria that you would like to investigate further.