Abstract
Introduction: Noncontact anterior cruciate ligament (ACL) injuries during sports have increased in the last few decades. Effective injury screening tools are crucial to identifying injury risk and allowing for intervention. A systematic review of the current literature will allow exercise science professionals and researchers to identify reliable, ecologically valid, and predictive methods utilised in the ACL injury screening process. This systematic review aims to identify, critically evaluate and summarise noncontact ACL injury screening methods' reliability, validity, and predictability.
Methods:
The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed for this review. We systematically searched for articles in English in eight electronic databases (PubMed, Scopus, Web of Science, SciELO Citation Index, Cochrane Library, Ovid MEDLINE(R), CINAHL Complete (EBSCOhost) and SPORTDiscus). A search was conducted through databases from their creation until the 19th of January, 2022. Inclusion criteria were: peer-reviewed full-text articles reporting ACL injury screening methods' reliability, validity, and predictability, articles that reported the analysis of primary ACL injury and considered the biomechanical evaluation of kinematic and kinetic variables of the hip, knee, and ankle during a specific sporting task in both frontal and sagittal planes and the study done on humans. We used the Newcastle-Ottawa Quality Assessment Scale for Cohort studies and the Cochrane Group on Screening and Diagnostic Test Methodology (Cochrane methods) quality assessment tool was conducted to identify study bias in the included reliability and validity studies and the included prospective studies, respectively. The review is registered at the International Prospective Register of Systematic Reviews (PROSPERO, CRD42022331391).
Results:
The search yielded 14,375 studies, with 75 studies eligible for inclusion. We identified several screening methods for noncontact ACL injury. Screening methods included; three-dimensional (3D) motion analysis, two-dimensional (2D) video motion analysis, the Landing Error Scoring System (LESS), the Functional Movement Screen (FMS), and Real-time Observational Screening. We identified specific ACL injury screening tasks, including; drop jumps with double-leg landing, side-cutting, and single-leg squats. In the included studies, 16 studies reported the ability to predict injury risk, 59 studies reported the reliability of the screening method, and 13 studies reported the validity of the screening method against the gold standard 3D motion analysis system. The 3D motion analysis demonstrated good to excellent intra-rater reliability, ranging from ICC= 0.760-0.980, and moderate to excellent inter-session reliability, ranging from ICC= 0.600-0.916. The assessment of inter-rater reliability was not reported in any identified study. The 2D video motion analysis showed moderate to excellent intra-rater reliability, ranging from ICC= 0.672-1.000, and good to excellent inter-session reliability, ranging from ICC= 0.720-0.960. Inter-rater reliability varied, ranging from ICC= 0.140-1.000. The LESS provided good to excellent intra-rater reliability, ranging from ICC= 0.680-0.990, and good to excellent inter-rater reliability, ranging from ICC= 0.710-0.950. Inter-session reliability was not assessed for the LESS in any included study. The FMS exhibited poor to excellent intra-rater reliability, ranging from ICC= 0.372-0.960, good to excellent inter-rater reliability, ranging from ICC= 0.760-0.980, and moderate to excellent inter-session reliability, ranging from ICC= 0.600-0.950. The Real-time Observational Screening showed moderate to excellent intra-rater and inter-rater reliability, ranging from K= 0.550-0.900 and K= 0.520-0.920, respectively.
Discussion:
The systematic review identified several methods and specific tasks for noncontact ACL injury screening. The identified studies reported on the screening methods' predictability, reliability, and validity, with 3D motion analysis, 2D video motion analysis, LESS, FMS, and Real-time Observational Screening being the most commonly used methods. In general, the results showed good to excellent intra-rater and inter-rater reliability and moderate to high validity for the different screening methods, suggesting that these methods can be used to identify individuals at risk of noncontact ACL injury.
Impact/Application to the field:
Findings from this research may be helpful to inform sports and exercise science professionals to identify reliable, ecologically valid, and predictive methods utilised in the noncontact ACL injury screening process to prevent future injuries in athletes.