The tear of the anterior rectus femoris is the most frequent injury of the quadriceps muscle group, and one of the most common causes of lower limb muscle lesions (after the injury of the hamstring muscle group). As its anatomy is complex, and symptoms may be unclear, imaging and in particular, Magnetic Resonance Imaging (MRI) provides precise information on the type of tear, topography, extent...

Simulation results suggest that the primary mechanism for improvement in knee flexion after surgery is reduction of the muscle’s knee extension moment, rather than conversion to a knee flexion moment. Scarred transfer simulations resulted in an average peak knee flexion improvement (14° ± 5°) comparable to the average increase in knee flexion range of motion (13° ± 11°) in the subjects’ postope...

BACKGROUND Coactivation may be both desirable (injury prevention) or undesirable (strength measurement). In this context, different styles of muscle strength stimulus have being investigated. In this study we evaluated the effects of verbal and visual stimulation on rectus femoris and biceps femoris muscles contraction during isometric and concentric. METHODS We investigated 13 men (age =23.1...

In healthy subjects, electromyography (EMG) reveals that well-coordinated walking can be produced by exciting four co-activation modules: Module 1 (hip and knee extensors) in early stance, Module 2 (ankle plantarflexors) in late stance, Module 3 (tibialis anterior and rectus femoris) during swing, and Module 4 (hamstrings) in late swing and early stance [1]. These modules, comprised of timing a...

A pneumatic exoskeleton intended to decrease the muscle activity of the knee extensors during walking on a negative slope is presented. The device consists of an air spring that can be engaged and disengaged via a solenoid valve. When engaged, the air spring resists knee flexion. A preliminary evaluation of the device was conducted with a single healthy subject. During testing, the EMG activity...

The average muscle activation for the major muscles such as rectus femoris (RF) and Gastrocnemius (GN) during running reveals that they need to exert higher muscle force without wearing compression garment. Previous evidences have shown that lower muscle activity at particular phases of gait cycle prolongs activity, reduces fatigue and reduces injury susceptibility. Therefore, it would seem tha...

In this research, surface electromyography (SEMG) signal analysis from the right rectus femoris muscle is performed during walk. Wavelet transform (WT) has been applied for removing noise from the surface SEMG. Gaussianity tests are conducted to understand changes in muscle contraction and to quantify the effectiveness of the noise removal process. Results show that the proposed method can effe...

(1) Background: this study aimed to determine if there are differences in quadriceps and hamstring muscle activation professional male female soccer players. (2) Methods: was recorded by surface electromyography 27 players (19 8 female). The performed the Bulgarian squat lunge exercises. Vastus medialis, vastus lateralis, rectus femoris, semitendinosus, biceps femoris were muscles analyzed. (3)...

purpose: this study aimed to examine the differences in the co-activation of the rectus femoris (rf) and biceps femoris (bf) using the co-contraction index (ci) in aquatic and land environments during a drop-landing task in active and non-active females. methods: in this casual-comparison study, 10 active and 10 non-active females volunteered to participate. the ci was calculated from recorded ...

A 13-year-old female sustained a rare avulsion fracture of the secondary ossification center in the superior margin of the acetabulum as the result of contraction of the reflected head of the rectus femoris muscle. Diagnosis was made from plain films and CT scans with 3D image reconstruction. The patient was treated non-operatively by bed rest with semiflexion of the hip and knee, and appropria...