Left fibularis tertius

Identify fibularis tertius

A small anterior-compartment muscle that helps lift the foot and turn the sole outward.

Unlike fibularis longus and brevis, tertius belongs to the anterior compartment. It is variable and is absent in some people.

Sources: Anterior-leg anatomy tables · OpenStax

From the shin toward the foot

It runs from the distal anterior fibula to the dorsal fifth metatarsal.

The regional lower-leg study omits foot bones. On this individual structure page, Show context restores the whole same-side leg, including the foot.

Sources: Anterior-leg anatomy tables

Foot lift and toe movement

It assists dorsiflexion and eversion.

Dorsiflexion brings the front of the foot toward the shin. Compare that with extending a toe: these are different movements, even when a muscle contributes to both.

The viewer shows a static source pose. Rotation changes your viewpoint, not the joint position; it does not simulate contraction, strength or walking.

Sources: Anterior-leg anatomy tables · OpenStax

Innervation

Motor supply is through the deep fibular (peroneal) nerve. That nerve is not displayed in this model.

Sources: Anterior-leg anatomy tables

Read the model

Explore left fibularis tertius in 3D

1. Follow the selected mesh. Inspect the isolated mesh from Front or Oblique. Restore context and compare its distal direction with the fifth metatarsal on the outer side of the foot.
2. Compare, then isolate. Show context restores 31 bones and 21 muscle parts on this side. Choose a neighboring muscle from the list, or use Isolate to remove surrounding surfaces again.
3. Return to the group. The lower-leg close-up contains the tibia, fibula and thirteen muscle parts, but no foot bones. Use these guides to compare all four anterior selections. Left anterior-leg guides →

Sources and editorial status

This guide uses independently written explanations with links to the evidence behind them. Source checking and specialist anatomical review are separate steps; the latter is still pending.

1. TTUHSC El Paso — Anterior & lateral leg and foot anatomy tables

   Principal attachments, actions and deep fibular nerve supply. Attachment summaries are introductory, not exhaustive maps.

2. OpenStax Anatomy and Physiology 2e — Appendicular muscles of the pelvic girdle and lower limbs

   Anterior muscles and dorsiflexion; fibularis tertius variability and tendon-retaining structures. No textbook text or images reproduced.

3D geometry and its separate license are credited beneath the viewer. References do not imply endorsement of this site.