This prospective cohort study developed and applied a multicomponent return-to-sport (RTS) test battery for patients after ACL reconstruction. The battery combined isokinetic strength, three hop tests, jump-landing quality (LESS), and two patient-reported outcomes (IKDC, ACL-RSI). The study asked how many patients at the traditional 6-month clearance timepoint actually meet rigorous, criteria-based RTS standards.
Young athletes have a 23% rate of second ACL injury after returning to high-activity sports — and prior to this work, most RTS decisions were based on subjective criteria or simple time (6 months) without systematic functional testing.
This paper operationalizes what criteria-based RTS actually looks like in practice. When you apply a rigorous battery, the failure rate is striking: 93% of patients at 6 months fall short on at least one criterion.
The key clinical lesson is to separate domains. Patients may pass hop tests but fail strength criteria, or pass self-reported outcomes while failing both. No single test captures readiness. This is why a battery matters.
For boards and clinical practice, know the thresholds: LSI >90% for strength and hops, quadriceps >3.0 Nm/kg normalized to body weight, H/Q ratio >55% (females) or >62.5% (males) at 300°/s, LESS <5, and ACL-RSI >56.
A practical limitation: the LSI has a known flaw. The uninvolved limb loses strength after ACL injury, so a patient can achieve LSI >90% while both limbs remain weaker than healthy controls. Absolute strength thresholds (like the 3.0 Nm/kg criterion) partially correct for this.
This prospective cohort study developed and applied a multicomponent return-to-sport (RTS) test battery for patients after ACL reconstruction. The battery combined isokinetic strength, three hop tests, jump-landing quality (LESS), and two patient-reported outcomes (IKDC, ACL-RSI). The study asked how many patients at the traditional 6-month clearance timepoint actually meet rigorous, criteria-based RTS standards.
Young athletes have a 23% rate of second ACL injury after returning to high-activity sports — and prior to this work, most RTS decisions were based on subjective criteria or simple time (6 months) without systematic functional testing.
This paper operationalizes what criteria-based RTS actually looks like in practice. When you apply a rigorous battery, the failure rate is striking: 93% of patients at 6 months fall short on at least one criterion.
The key clinical lesson is to separate domains. Patients may pass hop tests but fail strength criteria, or pass self-reported outcomes while failing both. No single test captures readiness. This is why a battery matters.
For boards and clinical practice, know the thresholds: LSI >90% for strength and hops, quadriceps >3.0 Nm/kg normalized to body weight, H/Q ratio >55% (females) or >62.5% (males) at 300°/s, LESS <5, and ACL-RSI >56.
A practical limitation: the LSI has a known flaw. The uninvolved limb loses strength after ACL injury, so a patient can achieve LSI >90% while both limbs remain weaker than healthy controls. Absolute strength thresholds (like the 3.0 Nm/kg criterion) partially correct for this.