Surgical Stabilization Results in Superior Clinical Outcome, Lower Recurrent Instability, and Reduced Risk of Meniscal Tears Relative to Nonoperative Treatment of ACL Rupture: A 3-Year Prospective Controlled Cohort Study.

Abstract

Background: There has been renewed interest in nonoperative treatment of anterior cruciate ligament (ACL) rupture following research suggesting that some ACL ruptures can heal naturally. However, the research is based on magnetic resonance imaging grading of ACL injuries rather than clinical signs, and the accuracy of the grading system is unknown. Nonoperative treatment of ACL ruptures has been associated with a higher risk of meniscal tears and recurrent instability, both of which may have long-term implications for the knee in terms of degeneration and the need for more complex stabilization surgery. More research into the nonoperative management of clinically significant ACL injuries is indicated before consideration for use in clinical practice.

Hypothesis: Operative management of ACL rupture improves clinical outcome relative to nonoperative management.

Study design: Cohort study; Level of evidence, 3.

Methods: The Covid-19 pandemic temporarily stopped elective surgery during 2020. For 2 months, those patients with isolated ACL ruptures underwent nonoperative treatment with bracing and physical therapy (Nonop group) were compared with a matched cohort undergoing ACL reconstruction (ACLR group) immediately before this period. Groups were compared at baseline with regard to age, gender, body mass index (BMI), lateral posterior tibial slope (LPTS), and the following patient-reported outcome measures (PROMs)-Tegner Activity Scale (TAS), International Knee Documentation Committee (IKDC), Sport and Recreation subscale (Sport/Rec) of the Knee injury and Osteoarthritis Outcome Score (KOOS), Knee Related Quality of Life (KR QoL) subscale of the KOOS, and Lysholm Knee Score (LKS)-as well as recurrent instability and meniscal tears, over a period of 3 years. Pearson chi-square test and analysis of variance were used for baseline characteristics, generalized linear models and multivariate tests for changes in PROMs, and chi-square tests for meniscal tears and recurrent instability. Statistical significance was accepted at P < .05.

Results: A total of 82 patients were recruited, 41 in each group. The ACLR group and the Nonop group were similar with regard to all baseline variables, with the following mean ± SD values, respectively: age in years (22.1 ± 3.8 vs 21.3 ± 3.4; P = .23), BMI in kg/m² (21.0 ± 2.0 vs 20.4 ± 2.5; P = .39), LPTS (8.1° ± 1.3° vs 7.9° ± 2.0°; P = .65), and preinjury TAS (8.2 ± 1.1 vs 8.7 ± 1.0; P = .33). The male:female ratio was 15:26 vs 17:24 (P = .71), respectively. At 3-year follow-up, the ACLR group had greater improvement in all PROMs than the Nonop group: TAS, 8.0 ± 1.0 vs 5.5 ± 0.9; IKDC, 90.9 ± 3.8 vs 65.0 ± 8.1; Sport/Rec, 92.4 ± 7.6 vs 66.6 ± 6.1; KR QoL, 91.1 ± 5.5 vs 74.3 ± 6.6; and LKS, 92.2 ± 4.9 vs 66.9 ± 6.1, respectively (all P < .001). There was a lower risk of both recurrent instability (5% vs 88%; P < .001) and medial meniscal tears (5% vs 63%; P < .001).

Conclusion: ACLR results in a highly statistically significantly better clinical outcome than nonoperative management of ACL rupture in terms of PROMs, as well as a lower risk of both recurrent instability and meniscal tears, over a period of 3 years.