Muscle Activation During ACL Injury Risk Movements in Young Female Athletes: A Narrative Review

Abstract

Young, adolescent female athletes are at particular high risk of sustaining a non-contact anterior cruciate ligament (ACL) injury during sport. Through the last decades much attention has been directed toward various anatomical and biomechanical risk factors for non-contact ACL injury, and important information have been retrieved about the influence of external loading factors on ACL injury risk during given sports-specific movements. However, much less attention has been given to the aspect of neuromuscular control during such movements and only sparse knowledge exists on the specific muscle activation patterns involved during specific risk conditions. Therefore, the aim of this narrative review was (1) to describe anatomical aspects, strength aspects and biomechanical aspects relevant for the understanding of ACL non-contact injury mechanisms in young female athletes, and (2) to review the existing literature on lower limb muscle activation in relation to risk of non-contact ACL-injury and prevention of ACL injury in young female athletes. Studies investigating muscle activity patterns associated with sports-specific risk situations were identified, comprising cohort studies, intervention studies and prospective studies. Based on the retrieved studies, clear gender-specific differences in muscle activation and coordination were identified demonstrating elevated quadriceps activity and reduced hamstring activity in young female athletes compared to their male counterparts, and suggesting young female athletes to be at elevated risk of non-contact ACL injury. Only few studies (n = 6) examined the effect of preventive exercise-based intervention protocols on lower limb muscle activation during sports-specific movements. A general trend toward enhanced hamstring activation was observed during selected injury risk situations (e.g., sidecutting and drop landings). Only a single study examined the association between muscle activation deficits and ACL injury risk, reporting that low medial hamstring activation and high vastus lateralis activation prior to landing was associated with an elevated incidence of ACL-injury. A majority of studies were performed in adult female athletes. The striking paucity of studies in adolescent female athletes emphasizes the need for increased research activities to examine of lower limb muscle activity in relation to non-contact ACL injury in this high-risk athlete population.

Injury Prevention in Youth Football Players : Training Effects and Programme Implementation

“…One study examined muscle activation patterns as an isolated risk factor for noncontact ACL injury 185 and showed reduced EMG pre-activity of the semitendinosus muscle and increased pre-activity of the vastus lateralis muscle before side-cutting in female handball and football players who later had a noncontact ACL injury compared to players who remained uninjured 185 . This study underlines the importance of medial hamstring muscle activation for the prevention of ACL injuries 14 .…”

“…In a study of female football and handball players, increased pre-activity of the medial hamstring muscle was seen after a period of IPEP training 184,186 . We do not know, however, how long these adaptations will be sustained in the absence of training or as the athletes get older and more mature 14 . One study showed that changed movement patterns after a three-month intervention were not retained, whereas movement patterns after a twelve-month intervention were, indicating the importance of long intervention periods 132 .…”

“…One study showed that changed movement patterns after a three-month intervention were not retained, whereas movement patterns after a twelve-month intervention were, indicating the importance of long intervention periods 132 . There are few studies of youth players, even though these are at highest risk of injury 14,133 . All in all, there is a dearth of studies regarding the biomechanical and neuromuscular training effects of IPEPs, with few studies evaluating the same IPEP 133 .…”

Contractile rate of force development after anterior cruciate ligament reconstruction—a comprehensive review and meta‐analysis

“…Studies aimed at identifying neuromuscular injury risk factors 118 are likely important for reducing ACL injury risk. Injury risk factor identification from athlete pre-season isokinetic strength assessments seems to play only a minor role in the prevention of ACL injury 119 or hamstring strain.…”

Countermovement Jump Assessment for Monitoring Prolonged Fatigue in Collegiate Female Soccer Players

“…Neuromuscular control is a risk factor that plays an important role in non-contact injury 6,10 , as it exhibits a sex dimorphism [16][17][18][19][20] and may be modifiable through training [45][46][47] .…”