AnatoMemory

Muscle

Plantaris

Vestigial calf muscle

Lower limbMuscular system

High-yield

Long thin tendon ("freshman's nerve"); weak plantarflexor; often absent. Tibial nerve.

Overview

A small muscle with a long slender tendon that weakly assists plantarflexion and knee flexion; often mistaken for a nerve.

Reference facts

Origin
Lateral supracondylar line of the femur
Insertion
Calcaneus (via a long thin tendon, medial to the Achilles)
Action
Weakly assists plantarflexion of the ankle and flexion of the knee
Innervation
Tibial nerve (S1, S2)
Blood supply
Sural arteries

Frequently asked questions

What does the plantaris do?

The plantaris weakly assists plantarflexion of the ankle and flexion of the knee.

What nerve innervates the plantaris?

The plantaris is innervated by the tibial nerve (S1, S2).

Where does the plantaris attach?

The plantaris originates from the lateral supracondylar line of the femur and inserts on the calcaneus (via a long thin tendon, medial to the Achilles).

What is the blood supply of the plantaris?

The plantaris is supplied by the sural arteries.