The minimal clinically important difference, patient acceptable symptom state and clinical outcomes of anterior cruciate ligament repair versus reconstruction. A matched-pair analysis from the santi study group

Background: There has been increasing interest in anterior cruciate ligament (ACL) repair because of theoretical advantages over ACL reconstruction; however, the contemporary literature has failed to provide high-quality evidence to demonstrate these advantages. Purpose: To compare the clinical and functional outcomes of ACL repair versus ACL reconstruction at a minimum follow-up of 2 years. Study Design: Cohort study; Level of evidence, 3. Methods: Patients who underwent ACL repair were propensity matched (based on demographics, time between injury and sur- gery, knee laxity parameters, presence of meniscal lesions, preoperative activity level, and sport participation), in a 1:1 ratio, to those who underwent ACL reconstruction during the same period. Isokinetic testing was used to evaluate strength deficits at 6 months postoperatively. Knee laxity parameters were evaluated at 12 months. Complications, return to sport, and patient-re- ported outcome scores were recorded at final follow-up. Results: In total, 75 matched pairs (150 patients) were evaluated. The repair group had significantly better mean hamstring mus- cle strength at 6 months compared with the reconstruction group (1.7% 6 12.2% vs 210.0% 6 12.8%, respectively; P .0001). At a mean final follow-up of 30.0 6 4.8 months, the repair group had a significantly better mean Forgotten Joint Score–12 (FJS-12) score compared with the reconstruction group (82.0 6 15.1 vs 74.2 6 21.7, respectively; P = .017). Noninferiority criteria were met for ACL repair, compared with ACL reconstruction, with respect to the subjective International Knee Documentation Committee score (86.8 6 9.0 vs 86.7 6 10.1, respectively; P .0001) and side-to-side anteroposterior laxity difference (1.1 6 1.4 vs 0.6 6 1.0 mm, respectively; P .0001). No significant differences were found for other functional outcomes or the pivot-shift grade. There were no significant differences in the rate of return to the preinjury level of sport (repair group: 74.7%; reconstruction group: 60.0%; P = .078). A significant difference was observed regarding the occurrence of ACL reruptures (repair group: 5.3%; recon- struction group: 0.0%; P = .045). Patients who experienced a failure of ACL repair were significantly younger than those who did not (26.8 vs 40.7 years, respectively; P = .013). There was no significant difference in rupture rates between the repair and recon- struction groups when only patients aged .21 years were considered (2.9% vs 0.0%, respectively; P = .157). The minimal clin- ically important difference and Patient Acceptable Symptom State (PASS) thresholds were defined for the ACL repair group. A significantly greater proportion of patients in the repair group achieved the PASS for the FJS-12 compared with their counterparts in the reconstruction group (77.3% vs 60.0%, respectively; P = .034). Conclusion: ACL repair was associated with some advantages over ACL reconstruction including superior hamstring muscle strength at 6 months and significantly better FJS-12 scores. However, the failure rate was significantly higher after ACL repair, and younger patients were particularly at risk.