The vastus medialis is a quadriceps muscle responsible for knee extension and patella stabilization. Weakness or injury to the muscle can lead to chondromalacia patellar or patellofemoral knee pain. Exercises such as squats and lunges activate the muscle, and treatment options include rest, ice, compression, elevation, prescription drugs, and physical therapy exercises.
The vastus medialis is a teardrop-shaped muscle of the lower thigh. The vastus medialis, one of the four muscles known collectively as the quadriceps, is responsible for extension of the knee joint and stabilization of the kneecap, or patella. Cycling, running, and lower body resistance exercises such as squats and lunges activate this muscle as the primary agonist. Weaknesses in the muscle, either as a result of injury or atrophy, are sometimes associated with a painful condition known as chondromalacia patellar or patellofemoral knee pain.
Broad, flat tendons known as aponeuroses anchor the vastus medialis along two lines of attachment on the upper surface of the femur. In addition, the muscular origin joins with that of the other muscles of the quadriceps group. This same type of connective tissue inserts most of the distal portion of the muscle into the shared tendon that attaches the quadriceps to the patella.
The lowest fibers of the muscle attach directly to the edge of the patella, separate from the other quadriceps. The patellar attachment is believed to function to stabilize any side-to-side movement of the patella during leg extension. Sometimes referred to as the vastus medialis oblique, or VMO, the muscle region involved in this particular attachment is visible on the leg as a teardrop-shaped muscle near the inner knee.
In general, most cardiovascular and lower body exercises stimulate the vastus medialis to some degree. To target the quad group, barbell squats, lunges, and leg extensions are popular options. Specifically isolating the vastus medialis from the other quadriceps muscles is more difficult, since they share common points of origin and insertion and govern the same movements. However, intensifications, adductor exercises, and deep squats, such as the Olympic squat, tend to place a greater degree of stress on the vastus medialis.
All of the quadriceps muscles function in knee extension, but the vastus medialis is particularly associated with the last 20° of extension. When the muscle has atrophied as a result of prolonged bed rest, movement of the knee joint becomes unstable and full extension may be impossible. It is this phenomenon that leads VMO to be associated with the pain and instability of the patellae of chondromalacia, often referred to simply as chondromalacia. The exact connection between the two, however, remains controversial.
Chondromalacia is not a specific disorder, but rather a set of symptoms that involve the knee. The theory behind the VMO-chondromalacia relationship is that weakness or injury to the VMO can lead to loss of patellar stability. This loss of stability can, in turn, lead to damage to the surrounding tissue as the kneecap slides back and forth during movement of the leg. Pain in the knees, particularly when squatting, sitting, or walking on stairs, along with knee clicking or a sudden loss of stability in the joint itself, are usually associated with the condition.
When transient, this type of knee pain can often be treated symptomatically, using a combination of rest, ice, compression, and elevation. If the pain continues, medical treatments, such as prescription drugs and physical therapy exercises, may be necessary. Although the recovery process from chondromalacia can be long, most patients usually make a full recovery.
Protect your devices with Threat Protection by NordVPN
