Let’s talk about sex (and gender) after ACL injury: a systematic review and meta-analysis of self-reported activity and knee-related outcomes

Abstract

ObjectiveInvestigate sex/gender differences in self-reported activity and knee-related outcomes after anterior cruciate ligament (ACL) injury.DesignSystematic review with meta-analysis.Data sourcesSeven databases were searched in December 2021.Eligibility criteriaObservational or interventional studies with self-reported activity (including return to sport) or knee-related outcomes after ACL injury.ResultsWe included 242 studies (n=123 687, 43% females/women/girls, mean age 26 years at surgery). One hundred and six studies contributed to 1 of 35 meta-analyses (n=59 552). After ACL injury/reconstruction, very low-certainty evidence suggests females/women/girls had inferior self-reported activity (ie, return to sport, Tegner Activity Score, Marx Activity Scale) compared with males/men/boys on most (88%, 7/8) meta-analyses. Females/women/girls had 23%–25% reduced odds of returning to sport within 1-year post-ACL injury/reconstruction (12 studies, OR 0.76 95% CI 0.63 to 0.92), 1–5 years (45 studies, OR 0.75 95% CI 0.69 to 0.82) and 5–10 years (9 studies, OR 0.77 95% CI 0.57 to 1.04). Age-stratified analysis (<19 years) suggests female athletes/girls had 32% reduced odds of returning to sport compared with male athletes/boys (OR 0.68, 95% CI 0.41 to 1.13, I20.0%). Very low-certainty evidence suggests females/women/girls experienced inferior knee-related outcomes (eg, function, quality of life) on many (70%, 19/27) meta-analyses: standardised mean difference ranging from −0.02 (Knee injury and Osteoarthritis Outcome Score, KOOS-activities of daily living, 9 studies, 95% CI −0.05 to 0.02) to −0.31 (KOOS-sport and recreation, 7 studies, 95% CI −0.36 to –0.26).ConclusionsVery low-certainty evidence suggests inferior self-reported activity and knee-related outcomes for females/women/girls compared with males/men/boys after an ACL injury. Future studies should explore factors and design targeted interventions to improve outcomes for females/women/girls.PROSPERO registration numberCRD42021205998.

The Delaware‐Oslo ACL Cohort treatment algorithm yields superior outcomes to usual care 9–12 years after anterior cruciate ligament reconstruction

“…Noncompleters at follow-up were more often male and younger, which is consistent with previous reports [32,39]. Although the pattern of missingness may skew the results in both directions [40,41], the risk of selection bias can be estimated to be minor as differences in preoperative KOOS scores were trivial (mean differences <3 points).…”

Anterior cruciate ligament injuries in female athletes: risk factors and strategies for prevention

“…This may be related to alterations in attention and coordination, together with increased muscular tension. 90 Bruder et al 91 found female athletes were 25% less likely to return to sport within the first five years after an ACL injury compared with their male counterparts. It has been suggested that fear of reinjury and lack of knee confidence are more likely to inhibit female athletes from returning to sports compared to males.…”

“…It has been suggested that fear of reinjury and lack of knee confidence are more likely to inhibit female athletes from returning to sports compared to males. 91,92 Also, while both males and females are motivated to be physically active, male athletes may be more likely to endorse competition and winning as motivators for sports participation and, therefore, exhibit more risk-taking behaviours. 93 Milewski et al 94 reviewed 176 patients with a mean age of 17 years undergoing ACLR and found that female athletes had significantly higher levels of injury-related stress and lower levels of perceived psychological readiness to return to sport compared with at six months after surgery.…”