Peroneus longus

A muscle that plays a crucial role in stabilizing the ankle and facilitating various movements of the foot.

The peroneus longus is a long muscle located in the lateral compartment of the leg. It arises from the upper portion of the fibula and the adjacent intermuscular septa, inserting onto the plantar aspect of the foot. This muscle is integral to the functioning of the lower limb, particularly in walking and running.

Terminologia Anatomica

musculus peroneus longus

System

Muscular system

Function

The primary function of the peroneus longus is to evert the foot, which means turning the sole outward away from the midline of the body. This motion is important for maintaining balance and stability during various activities, such as walking on uneven surfaces. Additionally, the peroneus longus assists in plantarflexion, helping to point the toes downward. By providing support to the arch of the foot, the muscle also aids in absorbing shock and distributing weight evenly across the foot when standing or moving. Its actions are vital in numerous athletic movements, enhancing performance in sports that require agility and quick directional changes.

Location

The peroneus longus is situated in the lateral part of the lower leg, running along the fibula. It originates from the head and upper two-thirds of the fibula, then travels downwards, crossing behind the lateral malleolus (the bony prominence on the outer side of the ankle). The tendon of the muscle then wraps around this bone, traveling beneath the foot before inserting into the base of the first metatarsal and the medial cuneiform. This unique path contributes to its efficient functioning in foot movement and stability.

Did You Know?

The peroneus longus is sometimes referred to as the fibularis longus, emphasizing its connection to the fibula bone.
Individuals with a stronger peroneus longus may have better balance and coordination, which is particularly beneficial for athletes.
Injury to the peroneus longus can lead to lateral ankle instability and affect overall lower limb performance.