Vastus Medialis Muscle details - origin, insertion and exercises.

Table of Contents

Vastus medialis Muscle Anatomy

The vastus medialis (vastus internus or teardrop muscle) is an extensor muscle located medially in the thigh that extends the knee. The vastus medialis is part of the quadriceps muscle group. It is present in the anterior compartment of thigh, and is one of the four muscles that make up the quadriceps muscle. The others are the vastus lateralis, vastus intermedius and rectus femoris.^[ It is the most medial of the “vastus” group of muscles.

Origin

It originates from the,

Lower part of the intertrochanteric line,
along the spiral line to the medial lip of the linea aspera
the medial intermuscular septum and the aponeurosis of adductor magnus.

Insertion

It inserts into the medial side of the quadriceps tendon, joining with rectus femoris, vastus lateralis, and vastus intermedius muscles, enveloping the patella, then by the patellar ligament into the tibial tuberosity .

Nerve supply

The posterior division of the femoral nerve (L3, L4) supplies the msucle.

Blood supply

The femoral artery and branches from the profunda femoris artery supplies the msucle.

Action

It acts as an extensor of the knee.

Strengthening Exercises

1. VMO Activation Exercises

Sit upright in a chair, with your knees bent, ball between your knees and your feet flat on the floor. Place your thumbs on the soft, squashy area on the inner side of the knee, just above your kneecaps and press down firmly
Clench your glutes and gently squeeze the ball, making sure the movement comes from your knee rather than the inner thigh
You should feel a tightening or swelling underneath your thumbs which shows you that you are activating vastus medialis and the VMO. That’s the area we want to make sure is working with all the exercises
If you can’t feel it, trying clenching your buttocks, clenching your knees and squashing the backs of your thighs down into the chair.

2. Twisted Leg Raise Exercises

Lie on your back with one leg stretched out straight and the other knee bent. This takes the tension off the lower back as you work the straight leg
Turn your foot outwards about 20^o into external rotation then lift the foot up until your thighs are parallel
Hold for 3 seconds and slowly lower down, keeping the foot turned outwards.
Keeping the leg turned outwards in this vastus medialis exercise again helps to activate the VMO.

Stretching Exercises

Stand holding a chair or the wall for balance
Bring your heel up behind you, grasp your ankle and pull your heel towards your buttock, until you feel a stretch, without bending forwards
This will stretch all 4 of the quads muscles but you can bias the stretch towards the vastus medialis muscle by moving your foot across your body towards the other buttock
Increase the stretch by pushing your hips forwards as you do the exercise
Hold for 30 seconds and repeat 3 times. Don’t bounce on and off the stretch, it’s much more effective to hold the stretch.

Clinical Relevance

Weakness of the vastus medialis is associated with patellar maltracking and patellofemoral pain. An approach to treatment attempts to restore balance between vastus medialis and lateralis, which requires strengthening of the oblique fibers of medialis, as well as assessment of the degree of dynamic supination and pronation of the foot.

VMO strengthening has become less popular approach to the treatment of anterior knee pain as the evidence supporting isolated exercises has been criticised for its poor quality. Furthermore researchers doubt the existence of VMO and have found that any quadriceps exercise will similarly activate the vastus muscles. Strengthening further up the kinetic chain has been suggested as more effective approach, Khayambashi et al. found that hip strengthening was more effective for improving patellofemoral pain than knee strengthening.

Vastus medialis muscle