What is the Fibularis Longus?
The fibularis longus is a long, rope-like muscle on the outside of your lower leg that helps control your ankle and support your foot. You may also see it called the peroneus longus. It begins on the upper portion of the fibula, the thinner bone on the outer side of the lower leg, and runs downward behind the bony bump on the outside of your ankle. Its tendon then travels under the foot and attaches near the base of the first metatarsal and the medial cuneiform, close to the big toe side.