PT  - JOURNAL ARTICLE
AU  - Ha, Sunghe
AU  - Jeon, Hyunggyu
AU  - Lee, Sae Yong
TI  - 107 Does ankle instability alter muscle activation of lower extremity and ground reaction force during landing? A meta-analysis
AID  - 10.1136/bjsports-2021-IOC.100
DP  - 2021 Nov 01
TA  - British Journal of Sports Medicine
PG  - A43--A43
VI  - 55
IP  - Suppl 1
4099  - http://bjsm.bmj.com/content/55/Suppl_1/A43.2.short
4100  - http://bjsm.bmj.com/content/55/Suppl_1/A43.2.full
SO  - Br J Sports Med2021 Nov 01; 55
AB  - Background Altered muscle activation pattern and ground reaction force (GRF) in those with ankle instability (AI) should be clearly investigated in order to incorporate this information to retrain AI patient.Objective To investigate muscle activation characteristics of AI patient and GRF pattern.Data Sources Relevant studies were searched from PubMed, CINAHL, SPORTDiscus, and Web of Science through May 2019. Combination of keywords ankle instability, chronic ankle instability, ankle sprain, biomechanics, kinetics, electromyography, and landing were used to search relevant studies.Study Selection Inclusion criteria for study selection were: 1) subjects with chronic ankle instability, functional instability, mechanical instability or recurrent ankle sprains; 2) the primary outcomes consisted of muscle activation of the lower extremity and GRF during landing; 3) peer-reviewed articles with full-text; and 4) providing appropriate information, which is mean, standard deviation, and sample size to re-analyze data.Data Extraction Extracted data included muscle activation of the lower extremity (root mean square; integral EMG; mean), the magnitude, and time to peak GRF and was used to calculate standardized mean differences (SMD) with 95% confidence intervals (CIs).Data Synthesis A total of twelve relevant studies (Oxford Centre for Evidence-Based Medicine level 3b) included in this study. The peroneal muscle was less activated in AI compared to control before landing (SMD=-0.59, p<0.01, CIs=-0.91, -0.27). AI had greater peak vertical GRF (SMD=0.21, p=0.03, CIs=0.02, 0.41) and exhibited shorter time to peak vertical GRF (SMD=-0.63, p<0.01, CIs=-0.85, -0.41) than those of control during landing (SMD=-0.63, p<0.01, CIs=-0.85, -0.41).Conclusions Muscle recruitment training of the peroneal muscle may diminish the risk of the recurrent ankle sprain in addition to other lower limb injuries. The peroneal muscle could provide a sufficient range of plantar flexion to decrease vertical GRF and eversion of the subtalar joint. Therefore, peroneal muscle training may be a key factor to retrain for the altered landing strategy resulting in ankle instability.