Corpus: Quadratus plantae muscle
1. Definition
2. Course
2.1. Origin
The quadratus plantae muscle originates from the calcaneus. The larger, fleshy medial head originates on the medial calcaneal surface below the sulcus, which contains the tendon of the flexor hallucis longus muscle.
The smaller, tendinous lateral head originates at the lateral edge of the inferior calcaneal surface.
2.2. Attachment
The quadratus plantae muscle attaches to the tendons of the flexor digitorum longus muscle.
3. Innervation
The quadratus plantae muscle is innervated by the lateral plantar nerve.
4. Function
The quadratus plantae muscle assists in flexing the toes and reinforces the action of the flexor digitorum longus muscle.