| Latin | Musculus vastus medialis |
|---|---|
| Origin |
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| Insertion |
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| Action |
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| Nerve | Femoral nerve (L2–L4) |
| Group | Quadriceps |
| Name | Latin vastus, 'huge', and medialis, 'towards the middle' — the huge muscle on the inner thigh. |
Palpation
- Client supine with the leg straight; stand beside the knee.
- Place your fingers on the inner thigh just above and to the inside of the patella.
- Feel the rounded, teardrop-shaped bulge; follow it upwards as it thins along the inner thigh.
- Ask the client to tighten the thigh and press the knee down into the table; the teardrop firms clearly under your fingers.
Vastus medialis runs along the whole inner side of the femur, but students mostly notice its lowest fibres: the teardrop bulge just above and inside the Patella. These oblique lower fibres are often called the VMO (vastus medialis obliquus). Wikipedia notes that splitting the muscle into separate “long” and “oblique” parts is still a hypothesis, so treat VMO as a handy name for the lower fibres rather than a separate muscle.
The origin line is described differently in different books. Wikipedia calls the part between the intertrochanteric line and the linea aspera the pectineal line; many textbooks call this stretch the spiral line. Both describe the same path down the back of the femur.
Higher up the thigh, vastus medialis sits next to Sartorius and the Adductors, with the femoral vessels running in a channel (the adductor canal) between them. Keep pressure broad and moderate on the upper inner thigh. Near the knee, Petrissage and small Circular friction around the teardrop suit a relaxation routine.