Clinical, Functional, Sports Participation, and Osteoarthritis Outcomes After ACL Injury
Authors: Urhausen Anouk P. , Pedersen Marie , Grindem Hege , Ito Naoaki , Arhos Elanna K. , Gunderson Ragnhild , Aune Arne Kristian , Engebretsen Lars , Axe Michael J. , Silbernagel Karin Grävare , Holm Inger , Snyder-Mackler Lynn , Risberg May Arna 
Published: February 2025

Background:
Anterior cruciate ligament reconstruction (ACLR) is often recommended for treatment of an ACL injury; however, the literature reports similar outcomes for those undergoing rehabilitation alone. We assessed the clinical, functional, sports participation, and osteoarthritis outcomes following our treatment algorithm, and compared 10-year outcomes among participants who chose progressive rehabilitation alone, early ACLR, or delayed ACLR.

Methods:
We included 276 participants who had a unilateral ACL injury without substantial concomitant knee injuries in a prospective cohort study. Treatment choice was based on shared decision-making after a 5-week progressive rehabilitation program. At the 10-year follow-up, we assessed patient-reported outcomes (International Knee Documentation Committee Subjective Knee Form [IKDC-SKF], Knee injury and Osteoarthritis Outcome Score [KOOS], and patient acceptable symptom state [PASS] achievement), quadriceps strength, hop performance, sports participation, and weight-bearing radiographs.

Results:
Sixty-nine percent of the participants (191 participants; 99 male and 92 female; 6 African American, 7 Asian, 59 Caucasian, 119 unknown) attended the 10-year follow-up, including 98% (53) of 54 participants who had rehabilitation alone, 68% (114) of 167 with early ACLR, and 69% (24) of 35 with delayed ACLR. Among the entire cohort, 78% (126 of 162) reported having a PASS, 72% (109 of 151) had symmetrical quadriceps strength, ≥85% (≥116 of ≤137) had a symmetrical hop performance, 93% (162 of 174) were still engaged in some kind of sports, only 1% (1 of 139) had symptomatic osteoarthritis, and 12% (17 of 139) had radiographic evidence of osteoarthritis. We found similar outcomes after rehabilitation alone and early ACLR. The participants who underwent delayed ACLR had similar outcomes to the other 2 groups except for significantly lower KOOS Sports scores, KOOS Quality of Life scores, and hop performance (p ≤ 0.03). Participants who had rehabilitation alone were older, less active, and more likely to have concomitant lateral meniscal injuries than those who underwent ACLR.

Conclusions:
Participants who followed our treatment algorithm after ACL injury had high percentages of satisfaction and of symmetrical quadriceps strength and hop performance, high sports participation rates, and low prevalences of osteoarthritis. Participants who chose progressive rehabilitation alone, despite being older and less active, had similar clinical, functional, sports participation, and osteoarthritis outcomes compared with those who chose early ACLR. Participants who underwent delayed ACLR scored lower on KOOS Sports, KOOS Quality of Life, and hop performance compared with both other groups.

Level of Evidence:
Therapeutic Level II. See Instructions for Authors for a complete description of levels of evidence.