Rectus femoris muscle
The rectus femoris muscle divides the front of the thigh in two and is located between the tailor muscle and the tensor of the broad fascia of the thigh. The rectus femoris muscle is the longest of all four heads of the quadriceps femoris — it is the only one that crosses the hip joint and is located most superficially. The rectus femoris muscle is bifurcated – its fibers go obliquely to the tendon located in the middle, attaching to it from two sides. Due to this structure, more muscle fibers are located on each section of this muscle compared to muscles that have a parallel arrangement of fibers, which provides it with great potential physical strength. It is the two-pinned arrangement of the fibers that makes this muscle the primary engine for flexion of the thigh and extension of the leg at the knee.
The rectus femoris muscle pulls the thigh bone forward in the hip joint when a person throws the shin forward in the limb transfer phase when walking. At the end of this movement, the heel of the forward foot takes the position necessary for full contact with the ground, and then takes on the weight of the body in the support phase. We make this two-joint movement not only when walking, but also when hitting a soccer ball or when the fluttering legs work in swimming.
In the hip joint, the rectus femoris muscle helps other muscles, such as the psoas major muscle, iliac muscle, tailor muscle and the fascia tensoris, while flexing the thigh in the hip joint. Since this muscle originates from the lower anterior iliac spine, it can also tilt the pelvis forward.
The rectus femoris muscle, the lateral femoralis major muscle, the intermediate femoralis major muscle, and the medial femoralis major muscle form the quadriceps femoris muscle. Together, they straighten the leg in the knee joint when we stand or lift something from the floor from a sitting position, that is, unbend the lower leg or bend the hips. All three “wide” muscles generate more power during these movements than the rectus femoris muscle. The strength of the “wide” muscles is provided by their larger cross-sectional area, large shoulder (thanks to the patella) and their main function – leg extension in the knee joint.
Very often, the rectus femoris muscle is overexerted, which leads to a forward inclination of the pelvis, a violation of the control of the glide path of the patella, and sometimes both. An increase in the forward inclination of the pelvis, as well as an increase in lumbar lordosis, can also be a result of overstrain of this muscle – it begins to pull the front part of the ilium forward and down towards the femur. As for the knee joint, during overstrain, the rectus femoris muscle begins to press on the articular surface or lower part of the patella, literally pushing it into the femoral groove. Prolonged pressure on the patella-femoral joint leads to inflammation, pain during movement, and in the most advanced cases to damage to the articular cartilage and various chronic problems with the knee joints, for example, osteoarthritis.
Chronic diseases, as well as violations of biomechanics and posture can be prevented – the rectus femoris muscle should be strengthened and stretched.
Palpation of the rectus femoris muscle
Position: customer is lying on his back
1. Stand on the side of the client facing his thigh. Locate the lower anterior iliac spine with your fingertips.
2. Slide your fingertips down between the tensor of the broad fascia of the thigh and the tailor muscle.
3. Do not palpate deeply – this muscle is located on the surface. Use your fingertips to probe the dense fibers of the rectus femoris muscle, resembling a feather in structure (as we have already said, this muscle has a bifurcated arrangement of fibers).
4. To make sure that you have correctly determined the location of this muscle, ask the client to carefully resist your movements, and at this time, straighten his leg at the knee and bend at the hip.
Stretching the rectus femoris using a masseur
Position: the client lies on his stomach, legs together
1. Stand on the side of the client between his hip and knee joints.
2. Carefully bend the leg of the client at the knee joint. Supporting the leg, grab the lower part of the knee with your hand.
3. With your other hand, stabilize the thigh by gently pushing toward the table.
4. Holding the thigh, with the other hand, straighten the leg in the thigh, tearing the knee from the table.
5. In order to better work out the area of the rectus femoris muscle at the knee joint, grab the client’s leg by the shin and bend it in the knee joint, while stabilizing the position of the thigh with the other hand.