The fibularis longus
Fibularis longus · musculus fibularis longus
An outer leg muscle whose tendon crosses under your foot to steady the ankle and arch.
What it does
The fibularis longus runs down the outside of the lower leg, behind the outer ankle and under the sole to the base of the big toe's metatarsal. It turns the sole outwards, helps point the foot and works with tibialis anterior like a stirrup to support the arch.
Surprising fact
Its tendon travels diagonally right across the sole, so a muscle on the outside of the leg helps pull down the base of the big toe.
Why it matters
After an ankle sprain, retraining this muscle with balance exercises helps prevent the ankle rolling again.
Nearby
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Sources
Drafted with AI help; awaiting a human fact-check against these sources.
Open in the 3D atlas · Suggest a correction · Not medical advice.
3D models: Z-Anatomy & BodyParts3D (CC BY-SA 4.0 / 2.1 JP). Card text CC BY 4.0.