Dance Anatomy & Kinesiology

The Ankle and Foot 317

Attachments and Primary Actions of Peroneal Muscles

Muscle Proximal attachment(s) Distal attachment(s) Primary actions(s)

Peroneus longus

(per-o-NEE-us LON-gus)

Lateral tibial condyle

Lateral aspect of upper two-

thirds of fibula

Lateral aspect of first

cuneiform

Proximal first metatarsal

Foot eversion

A-F plantar flexion

Depresses head of first

metatarsal

Peroneus brevis

(per-o-NEE-us BRE-vis)

Lateral aspect of lower two-

thirds of fibula

Tuberosity at proximal end

of fifth metatarsal

Foot eversion

A-F plantar flexion

the peroneal muscles. These lateral crural muscles cross the

lateral portion of the ankle behind the malleolus and both produce

eversion of the foot and ankle-foot plantar flexion.

Peroneus Longus

The peroneus longus (perone, fibula + longus, long) originates

from the lateral and upper portions of the tibia and fibula. It

courses superficially along the lateral lower leg and then contin-

ues under the foot to insert onto the undersurface of the first

cuneiform and first metatarsal (at the base of the great toe),

as shown in figure 6.21. Because the peroneus longus passes

behind the lateral malleolus to insert onto the plantar surface of

the foot, its line of pull is such that it can assist with ankle-foot

plantar flexion as well as perform its primary function of foot

eversion. In addition, because the peroneus longus courses

all the way under the foot to the inner aspect, it has the ability

to pull the medial aspect of the foot down into the supporting

surface and help control downward pressure of the first meta-

tarsal head in closed kinematic chain movements. Thus, the

peroneus longus is in a position to shift the body weight medi-

ally and help initiate pronation during walking, as well as help

position the great toe appropriately for push-off. The peroneus

longus is also in a position to offer support to various arches

of the feet. First, the peroneus longus passes under the apex

of the lateral longitudinal arch and thereby provides support for

this arch. Second, its medial attachment allows it to support

the transverse arch, functioning like a bowstring by pulling the

medial border toward the lateral border and helping to limit the

depression of the cuboid (Levangie and Norkin, 2001; Soderberg, 1986).

Peroneus Brevis

The peroneus brevis (perone, fibula + brevis, short) originates lower on the fibula than the longus and

runs deep to the longus for much of its upper course. As its name suggests, the peroneus brevis is a

shorter muscle than the peroneus longus, attaching distally onto the lateral foot (proximal fifth meta-

tarsal) rather than coursing underneath the foot as seen in figure 6.21. It shares a similar proximal

line of pull to the peroneus longus, and so it also assists with ankle-foot plantar flexion and is a prime

mover for foot eversion. The peroneals’ line of pull also enables them to produce abduction of the

forefoot, a motion used by dancers to create a beveled foot, a commonly used position in many ballet

and some modern schools of dance.

When weight bearing, both the peroneus longus and brevis are considered important dynamic stabiliz-

ers of the foot and the lower leg relative to the foot. These muscles provide an important counterbalance

for the invertors of the foot such as the tibialis anterior, tibialis posterior, and flexor hallucis longus and

are essential for preventing ankle inversion sprains.

FIGURE 6.21 Peroneus longus and brevis (right

foot, lateral and inferior views).

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