Neuromuscular activity of the lower‐extremities during running, landing and changing‐of‐direction movements in individuals with anterior cruciate ligament reconstruction: a review of electromyographic studies

Abstract

Purpose Running, jumping/landing and cutting/change of direction (CoD) are critical components of return to sport (RTS) following anterior cruciate ligament reconstruction (ACLR), however the electromyographic (EMG) activity patterns of the operated leg during the execution of these tasks are not clear. Methods A systematic review was conducted to retrieve EMG studies during running, jumping/landing and cutting/(CoD) in ACLR patients. MEDLINE, PubMed, SPORTDiscus and Web of Science databases were searched from 2000 to May, 2022 using a combination of keywords and their variations: “anterior cruciate ligament reconstruction” OR “ACLR”, “electromyography” OR “EMG”, “running”, “jumping” OR “landing”, “cutting” OR “change-of-direction” OR “CoD”. The search identified studies comparing EMG data during running, landing and cutting/(CoD) between the involved limb and contralateral or control limbs. Risk of bias was assessed and quantitative analyses using effect sizes were performed. Results Thirty two studies met the inclusion criteria. Seventy five percent (24/32) of the studies reported altered EMG activity pattern of the ACLR leg during running, jumping/landing and cutting/(CoD) when compared with either the healthy control leg or the contra-lateral leg. Twelve studies showed decreased, delayed or earlier onset and delayed peak in quadriceps EMG activity with small to large effect sizes and 9 studies showed increased, delayed or earlier onset and delayed peak in hamstrings EMG activity with small to large effect sizes. Four studies showed a “hamstrings-dominant” strategy i.e. decreased quadriceps coupled with increased hamstrings EMG activity in both running and jumping/landing irrespective of graft type. One study reported that on the grounds of decreased quadriceps activity, lower hamstrings EMG activity was predictive of ipsilateral re-injury in ACLR patients. Conclusion This systematic review of Level III evidence showed that the ACLR leg displays decreased quadriceps or increased hamstrings EMG activity or both despite RTS. Simultaneous decreased quadriceps and increased hamstrings EMG activity was shown for both running and jumping/landing. From a clinical perspective this “hamstrings dominant” strategy can serve as a protective mechanism against graft re-injury. Level of evidence III.

Postural Control During Single-Leg Landing in Female Athletes After Anterior Cruciate Ligament Reconstruction

“…Reduced muscle activity after RTS has been associated with poor performance and reduced dynamic stability of the knee during landing, 33 underscoring the clinical significance of understanding changes in muscle activity at RTS. 20,34 On the other hand, previous studies have reported earlier onset times or longer durations of muscle activities in the quadriceps and hamstring muscles before landing, 35 indicating increased pre-muscle activity as a protective mechanism to stiffen the joint in preparation for impact after landing. 36 However, these findings were mainly observed during the initial rehabilitation period (4 to 6 months post-surgery), whereas this study and others included subjects approximately 15 months 32 and 60 months 33 post-surgery.…”

Mechanical energy flow analysis in athletes with and without anterior cruciate ligament reconstruction during single-leg drop landing

“…We should consider that the prevalence of recurrent ACL rupture is high, and ranges from 1 to 11% 2 . Additionally, the prevalence of secondary contralateral ACL injury is as high as 1 in 4 3 , which suggests an elevated risk of ACL injury among athletes who have undergone a, ACLR 4 – 6 . Even with a significant volume of research underscoring the significance of consistent evaluation of quadriceps strength following ACLR, nearly half of clinicians persist in relying solely on the duration since surgery as the primary factor to determine an individual's readiness to resume sports activities after ACLR 65 .…”

“…The prevalence of recurrent ACL rupture is high, and ranges from 1 to 11% 2 . Additionally, the prevalence of secondary contralateral ACL injury is as high as 1 in 4 3 , which suggests an elevated risk of ACL injury among athletes who have undergone a, ACLR 4 – 6 .…”

“…Biomechanical factors include reduced knee flexion range of motion, increased internal rotation angle and valgus of the knee and decreased hip flexion and increased hip adduction 9 , 10 . Neuromuscular factors include smaller increases in activation of the vastus medialis, vastus lateralis, gastrocnemius lateralis, and changes in hamstring activation and co-contraction 6 , 11 . Kinetic factors include changes in the ground response forces and a decrease in the extensor torque of the knee and ankle 12 , 13 during dynamic activities including squat, single-leg drop landing (SLL), gait, and running 5 .…”

“…Subsequent ACL injury may be able to be predicted by the state of the hip, knee, and ankle joints. To prevent secondary ACL injury, altered biomechanical adaptations should be studied 4 , 6 as a possible crucial biomechanical chains, but, these adaptations commonly have been examined locally in every joint. Thus, the ability to control joint motion and absorb the body's kinetic energy during landing is particularly important for athletic populations given the high physical demands of sport.…”