Fibularis brevis

Fibularis brevis muscle
Fibularis brevis muscle
	Coronal section through right talocrural and talocalcaneal joints. (Label for Peroneus brevis is at right, third from the bottom.)
	The mucous sheaths of the tendons around the ankle. Lateral aspect. (Peroneus brevis labeled at bottom left.)
Details
Origin	Lower two-thirds of lateral fibula
Insertion	Fifth metatarsal
Artery	Fibular artery (peroneal artery)
Nerve	Superficial fibular nerve
Actions	Plantarflexion, eversion
Identifiers
Latin	Musculus fibularis brevis, ; musculus peronaeus brevis
TA98	A04.7.02.042
TA2	2653
FMA	22540
	Anatomical terms of muscle [edit on Wikidata]

The fibularis brevis muscle (or peroneus brevis) lies under cover of the peroneus longus, and is a shorter and smaller muscle.

Structure

It arises from the lower two-thirds of the lateral surface of the body of the fibula, medial to the peroneus longus, and from the intermuscular septa separating it from the adjacent muscles on the front and back of the leg.

The fibers pass vertically downward, and end in a tendon which runs behind the lateral malleolus along with but in front of that of the preceding muscle, the two tendons being enclosed in the same compartment and lubricated by a common mucous sheath.

It then runs forward on the lateral side of the calcaneus, above the calcaneal tubercle and the tendon of the peroneus longus, and is inserted into the tuberosity at the base of the fifth metatarsal bone, on its lateral side. When the base of the fifth metatarsal is fractured, the peroneus brevis may pull on and displace the proximal fragment (Jones Fracture). An inversion sprain of the foot may pull the tendon such that it avulses the tuberosity at the base of the fifth metatarsal.

Innervation

It is also innervated by the superficial fibular (peroneal) nerve.

Function

The muscle assists in weak plantarflexion and eversion of the foot.

History

Etymology

The terms "Peroneal" (i.e., Artery, Retinaculum) and "Peroneus" (i.e., Longus and Brevis) are derived from the Greek word Perone (pronounced Pair-uh-knee) meaning pin of a brooch or a buckle. In medical terminology, both terms refer to being of or relating to the fibula or to the outer portion of the leg.