Fibularis Brevis Muscle

Origin

The fibularis brevis muscle originates from the:

- distal half of the lateral surface of fibula;

- adjacent intermuscular septa.

Insertion

The fibers of the fibularis brevis muscle travel inferiorly to the foot and insert, via a long tendon, onto the dorsal aspect of the tuberosity of fifth metatarsal bone.

Key Features & Anatomical Relations

The fibularis brevis (peroneus brevis) muscle is found in the lateral compartment of the leg. It is a short, fusiform type of skeletal muscle. Superior to the ankle joint, the muscle belly gives rise to a tendon that travels inferiorly towards the malleolar groove of the fibula. The tendon hooks around the groove, changing its line of pull to a more anteroinferior direction. This tendon then travels deep to the superior and inferior fibular retinacula, anterior to the adjacent tendon of fibularis longus, where it passes through the common tendinous sheath of fibularis muscles. Along the lateral aspect of the foot, the tendon continues to travel anteroinferiorly, passing superior to the fibular trochlea of calcaneus, and then to its insertion site.

The fibularis brevis muscle is located:

- anterior to the fibularis longus and flexor hallucis longus muscles;

- posterior to the extensor digitorum longus muscle;

- lateral to the fibula, calcaneus and the flexor hallucis longus muscle.

Actions & Testing

The fibularis brevis muscle is involved in multiple actions:

- everts the foot at the subtalar and transverse tarsal joints;

- assists in plantarflexion of the foot at the ankle joint.

The fibularis brevis muscle can be tested by everting at the subtalar and transverse tarsal joints against resistance, during which its tendon can be seen and palpated (Sinnatamby, 2011).

References

Sinnatamby, C. S. (2011) Last's Anatomy: Regional and Applied. ClinicalKey 2012: Churchill Livingstone/Elsevier.