Author: Dr Peter de Souza
Last modified: 6 November 2022


The muscle indicated is the gracilis.

The gracilis is one of six muscles in the medial compartment of the thigh. The thigh consists of three muscular compartments:

  1. Anterior     
  2. Medial
  3. Posterior

The medial compartments consists of the following muscles:

  1. Gracilis
  2. Pectineus
  3. Adductor longus
  4. Adductor brevis
  5. Adductor magnus
  6. Obturator externus

The gracilis is the most superficial muscle in the medial compartment. It is a thin muscle which descends vertically down the medial aspect of the thigh.

  • Origin: inferior pubic ramus, ramus of ischium
  • Insertion: proximal shaft of tibia medially (pes anserinus)
  • Action: Adduction of thigh at hip join, flexion of knee
  • Innervation: Obturator nerve

The tendon of the gracilis inserts just above the point at which the semitendinosus muscle insertions and just behind the point where the sartorius inserts. The tendons of these three muscles (semitendinosus, gracilis and sartorius) are jointly referred to as the pes anserinus.