The Impact of Gender on the Landing Error Scoring System: A Systematic Review and Meta-Analysis

Abstract

Background

Women are more likely than men to experience injuries to the anterior cruciate ligament (ACL). Biomechanical differences, assessed using tools such as the Landing Error Scoring System (LESS), may contribute to this risk. The LESS does not directly influence ACL injury risk but helps identify individuals who might be at higher risk. However, conflicting findings in the literature prevent clear conclusions about sex-based differences in LESS scores. This study systematically reviews and meta-analyzes research examining the influence of sex on LESS scores.

Methods

Four databases (ScienceDirect, PubMed, Web of Science, and Scopus) were searched from 2009 (when LESS was introduced) to May 21, 2024. Only studies evaluating the impact of sex on LESS scores were included. Studies were screened for bias risk and critically appraised. A meta-analysis was performed utilizing a random-effects model, where sex served as the independent variable and LESS scores represented the dependent variable. The quality of evidence was assessed with the GRADE criteria. This study was registered with PROSPERO.

Results

Sixteen studies met the inclusion criteria. Females showed significantly higher LESS scores than males (p < 0.0001), with a mean difference of 0.62 errors. However, substantial heterogeneity was observed across studies, and the overall quality of evidence was rated as very low according to GRADE.

Conclusions

Although a statistically significant difference between sexes was identified, the mean difference of 0.62 errors is not clinically meaningful. The findings should be interpreted with caution due to their high heterogeneity and very low–quality evidence. Furthermore, sex differences in LESS scores may be context-dependent and influenced by population characteristics and study conditions.