The plantaris is a small muscle within the superficial compartment of the posterior leg. It is absent in approximately 10% of the population.
- Attachments: Originates from the lateral supracondylar line of the femur. The fibres condense into a tendon which travels down the leg, between the gastrocnemius and soleus muscles. It blends with the calcaneal tendon and inserts onto the calcaneus.
- Actions: Contributes to plantarflexion at the ankle joint and flexion at the knee joint.
- Innervation: Tibial nerve.
- Blood supply: Lateral sural artery (branch of the popliteal artery).