Bioelectrical Activity of Vastus Medialis and Rectus Femoris Muscles in Recreational Runners with Anterior Knee Pain

Abstract

Patellofemoral pain syndrome (PFPS), the most common source of knee pain among physically active individuals, is defined as anterior knee pain involving the patella and retinaculum that excludes other intraarticular and peri-patellar pathology. Differences in the activation and endurance of the quadriceps components, causing an imbalance in the forces controlling patellar tracking during flexion and extension in the knee joint, appear to be the most commonly reported risk factors for PFPS. The aim of this study was to determine the differences in bioelectric activity of vastus medialis and rectus femoris muscles during half knee bend position in runners with PFPS. The sample comprised 20 recreational runners (15 males, 5 females; aged 27 ± 5 years) reporting knee pain and diagnosed with PFPS. The age- and sex-matched control group consisted of recreational runners who did not report knee pain. The myon electromyographic system was used to determine the changes in the electromyographic median frequency during a half squat position. The decrease in the median frequency of vastus medialis and rectus femoris muscles was significantly greater in runners with PFPS in comparison to the control group (p < 0.01 for right and left vastus medialis and right rectus femoris; p < 0.05 for left rectus femoris). There is a relationship between knee pain related to PFPS and the imbalance of bioelectric activity of vastus medialis and rectus femoris muscles. Achieving the muscular balance within the thigh muscles can be an important factor in the rehabilitation process of PFPS.

The effect of gender on vastus medialis oblique/vastus lateralis activation ratio during weight and non-weight bearing activities in recreationally subjects

“…The average of VMO/VL activation ratio during stepdown activity was lower in participants with PFPS compared to healthy subjects. 43,48,49 These findings may indicate that PFPS may be related to lowered activity of VMO muscle 3 , and the authors also observed that the activity of VMO and VL in healthy females was doubled to enable them to execute the stepdown activity compared to the males. The current study did not find gender differences in VMO/VL activation ratio in healthy subjects, but such differences may be present in subjects with PFPS.…”

“…2 A study reported that in runners of both genders with PFP syndrome, there was a significant decrease in the VM and rectus femoris (RF) muscle activation compared to the control group, indicating a relationship between knee pain related to PFPS and the imbalance of bioelectric activity of VM and RF muscles. 3 Recently, Pavone et al 4 reported that the incidence of clinical symptoms connected to PFPS was not correlated with the amount of athletic activity in young female athletes.…”

The impact of knee pain on body balance and electromyographic activity of the quadriceps muscle in fencers during the lunge movement

“…Pain located at the front of the knee can significantly affect the activation of the rectus femoris muscle. Imbalance in the work of the quadriceps muscles can also cause a decrease in activating the rectus femoris muscles in individuals who experience pain [22]. Voight and Wieder suggested that motor control deficits in patients with knee pain could reverse the activation sequence of the vastus medialis and vastus lateralis muscles, leading to decreased rectus femoris muscle activation [23].…”

Sex-dependent differences in single-leg squat kinematics and their relationship to squat depth in physically active individuals

“…Functional performance tests are often used for an assessment of dynamic movement patterns that are part of more complex activity. Lower extremity kinematics and muscle activity have been documented during closed kinetic chain exercises such as jumping and landing or squatting in healthy as well as in patient populations 1 – 3 . These tests evaluate movement in all three planes of motion, the range of motion, strength and proprioception.…”