KSSTA - 2026-08-26 - Journal Article
Patient-reported acceptable symptom state does not reflect quadriceps symmetry 1 year after ACL reconstruction.
Pineda T, Varady NH, Mazy D, Jacquet C, Druel J, Ollivier M
Topics
Key Takeaway
At 12 months post-ACLR, 76% of patients meeting the KOOS Sport PASS threshold (≥75) had concurrent quadriceps LSI below 90%, with near-zero agreement between PASS achievement and isokinetic symmetry (κ = 0.060 for KOOS Sport, κ = 0.030 for KOOS QoL).
Summary Depth
Choose how much analysis to show on this article page.
Summary
This study quantified concordance between validated PASS thresholds (KOOS Sport ≥75; KOOS QoL ≥62.5) and isokinetic quadriceps LSI ≥90% at 1 year in 90 consecutive primary ACLR patients allocated equally across rectus femoris, quadriceps tendon, and hamstring autograft groups with systematic anterolateral augmentation. Agreement between PASS achievement and quadriceps symmetry was essentially absent (KOOS Sport κ=0.060, KOOS QoL κ=0.030; both McNemar p<0.001), with 42 patients (46.7%) meeting KOOS Sport PASS while failing LSI ≥90%. Discordance was independent of autograft type (RF 50%, QT 47%, HS 43%; p=0.875).
Key Limitation
Assessment at a single 12-month time point does not capture whether the discordance between PASS and LSI resolves with continued rehabilitation, leaving the clinical trajectory of the 76% discordant patients unknown.
Original Abstract
PURPOSE
To quantify the agreement between achievement of the validated patient acceptable symptom state (PASS) thresholds for Knee injury and Osteoarthritis Outcome Score (KOOS) Sport and KOOS Quality of Life (QoL) and isokinetic quadriceps limb symmetry index (LSI) ≥ 90% in a prospective cohort undergoing primary anterior cruciate ligament reconstruction (ACLR), and to determine whether this agreement was modified by autograft type.
METHODS
Ninety consecutive patients undergoing primary ACLR with systematic anterolateral augmentation were prospectively allocated to three autograft groups in cohorts of 30: rectus femoris (RF), quadriceps tendon (QT) and hamstrings (HS). At 12 months postoperatively, all patients underwent concentric isokinetic testing at 60°/s and completed the KOOS Sport and Recreation and KOOS QoL subscales. Concordance between PASS achievement (KOOS Sport ≥75; KOOS QoL ≥62.5) and quadriceps LSI ≥ 90% was analysed using Cohen's kappa with bootstrap 95% confidence intervals and McNemar exact test.
RESULTS
Agreement between PASS achievement and isokinetic quadriceps symmetry was absent: KOOS Sport versus LSI κ = 0.060 (95% confidence interval [CI] -0.071 to 0.191; McNemar p < 0.001); KOOS QoL versus LSI κ = 0.030 (95% CI -0.062 to 0.122; McNemar p < 0.001). Forty-two patients (46.7%) met the KOOS Sport PASS threshold while showing LSI < 90%, compared with only five patients who achieved quadriceps LSI ≥ 90% without meeting the KOOS Sport PASS threshold. Among patients who reached the KOOS Sport PASS threshold, 76% had concurrent quadriceps LSI scores below 90%. The pattern was consistent across the three autograft groups (RF 50%, QT 47%, HS 43%; χ 2 p = 0.875).
CONCLUSION
PASS achievement and isokinetic quadriceps symmetry capture distinct dimensions of recovery 1 year after ACLR. The two assessments diverged in approximately half of the cohort, and this discordance was independent of autograft type. Patient-reported and objective measures should be regarded as complementary rather than interchangeable, and a satisfactory PROM result alone should not be taken as evidence of restored quadriceps symmetry.
LEVEL OF EVIDENCE
Level II, prospective comparative study.