Background:For the past 30 years,the hamstring(H)-to-quadriceps(Q)(H:Q)torque ratio has been considered an important index of muscle strength imbalance around the knee joint.The purpose of this systematic review was t...Background:For the past 30 years,the hamstring(H)-to-quadriceps(Q)(H:Q)torque ratio has been considered an important index of muscle strength imbalance around the knee joint.The purpose of this systematic review was to examine the value of H:Q torque ratio as an independent risk factor for hamstring and anterior cruciate ligament(ACL)injuries.Methods:Database searches were performed to identify all relevant articles in PubMed,MEDLINE,Cochrane Library,and Scopus.Prospective studies evaluating the conventional(concentric H:Q),functional(eccentric H:concentric Q),and mixed(eccentric H at 300/s:concentric Q at2400/s)H:Q ratios as risk factors for occurrence of hamstring muscle strain or ACL injury were considered.Risk of bias was assessed using the Quality In Prognosis Studies tool.Results:Eighteen included studies reported 585 hamstrings injuries in 2945 participants,and 5 studies documented 128 ACL injuries in 2772participants.Best evidence synthesis analysis indicated that there is very limited evidence that H:Q strength ratio is an independent risk factor for hamstring and ACL injury,and this was not different between various ratio types.Methodological limitations and limited evidence for ACL injuries and some ratio types might have influenced these results.Conclusion:The H:Q ratio has limited value for the prediction of ACL and hamstring injuries.Monitoring strength imbalances along with other modifiable factors during the entire competitive season may provide a better understanding of the association between H:Q ratio and injury.展开更多
Although injury and neuromuscular activation patterns may be common for all individuals, there are certain factors which differentiate neuromuscular activity responses between children, adults and elderly. The purpose...Although injury and neuromuscular activation patterns may be common for all individuals, there are certain factors which differentiate neuromuscular activity responses between children, adults and elderly. The purpose of this study is to review recent evidence on age differences in neural activation and muscle balances around the knee when performing single joint movements. Particularly, current evidence indicates that there are some interesting similarities in the neuromuscular mechanisms by which children or the elderly differ compared with adults. Both children and elderly display a lower absolute muscle strength capacity than adults which cannot fully be explained by differences in muscle mass. Quadriceps activation failure is a common symptom ofall knee injuries, irrespective of age but it is likely that its effect is more evident in children or adults. While one might expect that antagonist co-activation would differ between age categories, it appears that this is not the case. Although hamstring: quadriceps ratio levels are altered after knee injury, it is not clear whether this is an age specific response. Finally, evidence suggests that both children and the elderly display less stiffness of the quadriceps muscle-tendon unit than adults which affects their knee joint function.展开更多
文摘Background:For the past 30 years,the hamstring(H)-to-quadriceps(Q)(H:Q)torque ratio has been considered an important index of muscle strength imbalance around the knee joint.The purpose of this systematic review was to examine the value of H:Q torque ratio as an independent risk factor for hamstring and anterior cruciate ligament(ACL)injuries.Methods:Database searches were performed to identify all relevant articles in PubMed,MEDLINE,Cochrane Library,and Scopus.Prospective studies evaluating the conventional(concentric H:Q),functional(eccentric H:concentric Q),and mixed(eccentric H at 300/s:concentric Q at2400/s)H:Q ratios as risk factors for occurrence of hamstring muscle strain or ACL injury were considered.Risk of bias was assessed using the Quality In Prognosis Studies tool.Results:Eighteen included studies reported 585 hamstrings injuries in 2945 participants,and 5 studies documented 128 ACL injuries in 2772participants.Best evidence synthesis analysis indicated that there is very limited evidence that H:Q strength ratio is an independent risk factor for hamstring and ACL injury,and this was not different between various ratio types.Methodological limitations and limited evidence for ACL injuries and some ratio types might have influenced these results.Conclusion:The H:Q ratio has limited value for the prediction of ACL and hamstring injuries.Monitoring strength imbalances along with other modifiable factors during the entire competitive season may provide a better understanding of the association between H:Q ratio and injury.
文摘Although injury and neuromuscular activation patterns may be common for all individuals, there are certain factors which differentiate neuromuscular activity responses between children, adults and elderly. The purpose of this study is to review recent evidence on age differences in neural activation and muscle balances around the knee when performing single joint movements. Particularly, current evidence indicates that there are some interesting similarities in the neuromuscular mechanisms by which children or the elderly differ compared with adults. Both children and elderly display a lower absolute muscle strength capacity than adults which cannot fully be explained by differences in muscle mass. Quadriceps activation failure is a common symptom ofall knee injuries, irrespective of age but it is likely that its effect is more evident in children or adults. While one might expect that antagonist co-activation would differ between age categories, it appears that this is not the case. Although hamstring: quadriceps ratio levels are altered after knee injury, it is not clear whether this is an age specific response. Finally, evidence suggests that both children and the elderly display less stiffness of the quadriceps muscle-tendon unit than adults which affects their knee joint function.
