Anterior thigh

Vastus intermedius

Extends the leg at the knee as the deep central portion of the quadriceps femoris

Origin: Anterior and lateral surfaces of the femoral shaft
Insertion: Tibial tuberosity through the quadriceps tendon, patella, and patellar ligament
Primary actions: Extends the leg at the knee as the deep central portion of the quadriceps femoris

Anatomy reference

OpenStax Anatomy and Physiology 2e — Pelvic Girdle and Lower Limbs

Open reference

Educational anatomy reference only. This page does not diagnose pain, injury, or movement limitations.

From anatomy to action

Explore the movement, not just the muscle.

A single muscle rarely explains a movement by itself. Use the related movement content to see how this anatomy may contribute, then choose a focused program when you want a complete progression.

Corrective movement strategies and exercises

Mobility focus

Knee Dominance

Explore squat and step variations that distribute effort comfortably across the foot, knee, and hip.

Open corrective movement strategy