what muscle everts the foot

2 min read 23-02-2025

The human foot is a complex structure, capable of a wide range of movements. One crucial movement is eversion, the turning of the sole of the foot outward, away from the midline of the body. Understanding which muscles perform this action is key to understanding foot mechanics and addressing potential injuries. This article will explore the primary muscle responsible for eversion and the supporting players in this important movement.

The Primary Evertor: Peroneus Longus

The peroneus longus muscle is the primary muscle responsible for everting the foot. Originating on the head and upper two-thirds of the fibula (the outer bone of the lower leg), it runs down the lateral side of the leg. Its tendon then travels behind the lateral malleolus (the outer ankle bone) before passing under the foot to insert on the medial cuneiform and first metatarsal bones. This long tendon path allows for significant leverage, making it highly effective at eversion.

Peroneus Brevis: A Supporting Player

While the peroneus longus is the star of the show, the peroneus brevis muscle plays a significant supporting role in foot eversion. Situated deep to the peroneus longus, it also originates on the fibula, but lower down. Its tendon passes behind the lateral malleolus and inserts onto the base of the fifth metatarsal. Although primarily an evertor, it also contributes to plantarflexion (pointing the toes downward).

Other Muscles Contributing to Eversion

While the peroneus longus and brevis are the main evertors, other muscles can contribute to this movement, depending on the specific context:

Peroneus Tertius: This muscle, located on the anterior (front) compartment of the lower leg, assists in eversion and dorsiflexion (lifting the toes upward).
Extensor Digitorum Brevis: This muscle contributes slightly to eversion, but its primary function involves extending the toes.
Extensor Hallucis Brevis: Located on the top of the foot, this muscle helps extend the big toe and can also play a minor role in eversion.

Understanding Eversion's Importance

Eversion is a critical movement for various activities, including walking, running, and jumping. It allows the foot to adapt to uneven surfaces and provides stability during movement. Weakness or injury to the evertor muscles can lead to instability, pain, and even gait abnormalities.

What Happens When Eversion Muscles Are Injured?

Injury to the peroneus longus or brevis, often from overuse or sudden trauma, can result in several problems. These include:

Peroneal Tendonitis: Inflammation of the tendons of these muscles.
Peroneal Tendon Subluxation/Dislocation: The tendons can slip out of their normal groove behind the lateral malleolus.
Peroneal Tendon Rupture: A complete tear of the tendon.

Strengthening the Evertors: Exercises and Prevention

Strengthening the evertor muscles is essential for maintaining foot health and preventing injuries. Here are some exercises that target these muscles:

Resisted Eversion: Using a resistance band around the foot, resist eversion against the band.
Heel Raises on an Incline: Elevating the heel onto a slightly elevated surface while maintaining balance engages the evertors.
Seated Toe Raises with Resistance Band: Sit with legs extended and resist eversion against a resistance band.

By understanding the muscles involved in eversion and their role in foot function, individuals can take steps to prevent injuries and maintain healthy foot mechanics. If experiencing foot pain or instability, consult a healthcare professional for proper diagnosis and treatment.

Disclaimer: This article provides general information and should not be considered medical advice. Always consult with a healthcare professional for any health concerns or before starting a new exercise program.