TY - JOUR T1 - Effect of unplanned athletic movement on knee mechanics: a systematic review with multilevel meta-analysis JF - British Journal of Sports Medicine JO - Br J Sports Med SP - 1366 LP - 1378 DO - 10.1136/bjsports-2021-103933 VL - 55 IS - 23 AU - Florian Giesche AU - Felix Stief AU - David A Groneberg AU - Jan Wilke Y1 - 2021/12/01 UR - http://bjsm.bmj.com/content/55/23/1366.abstract N2 - Objective To compare the effects of pre-planned and unplanned movement tasks on knee biomechanics in uninjured individuals.Design Systematic review with meta-analysis.Data sources Five databases (PubMed, Google Scholar, Cochrane Library, ScienceDirect and Web of Science) were searched from inception to November 2020. Cross-sectional, (randomised) controlled/non-controlled trials comparing knee angles/moments of pre-planned and unplanned single-leg landings/cuttings were included. Quality of evidence was assessed using the tool of the Grading of Recommendations Assessment, Development and Evaluation working group.Methods A multilevel meta-analysis with a robust random-effects meta-regression model was used to pool the standardised mean differences (SMD) of knee mechanics between pre-planned and unplanned tasks. The influence of possible effect modifiers (eg, competitive performance level) was examined in a moderator analysis.Results Twenty-five trials (485 participants) with good methodological quality (Downs and Black) were identified. Quality of evidence was downgraded due to potential risk of bias (eg, confounding). Moderate-quality evidence indicates that unplanned tasks evoked significantly higher external knee abduction (SMD: 0.34, 95% CI: 0.16 to 0.51, 14 studies) and tibial internal rotation moments (SMD: 0.51, 95% CI: 0.23 to 0.79, 11 studies). No significant between-condition differences were detected for sagittal plane mechanics (p>0.05). According to the moderator analysis, increased abduction moments particularly occurred in non-professional athletes (SMD: 0.55, 95% CI: 0.14 to 0.95, 5 studies).Conclusion Unplanned movement entails higher knee abduction and tibial internal rotation moments, which could predispose for knee injury. Exercise professionals designing injury-prevention protocols, especially for non-elite athletes, should consider the implementation of assessments and exercises requiring time-constrained decision-making.PROSPERO registration number CRD42019140331. ER -