Where does the fibularis longus muscle insert?

The fibularis longus muscle, also known as peroneus longus, is an important muscle located in the lateral compartment of the leg. It plays a significant role in eversion and plantar flexion of the foot. The correct insertion point for the fibularis longus is at the base of the 1st metatarsal and the medial cuneiform bone.

This insertion allows the muscle to help stabilize the foot and support the arch during activities like walking and running. By attaching at this specific location, the fibularis longus contributes significantly to the movement and support of the foot.

The other options refer to insertion points that do not correspond to the anatomical path of the fibularis longus. The lateral surface of the 5th metatarsal is associated with a different muscle, while the proximal surface of the 2nd metatarsal and the anterior surface of the calcaneus do not match the fibularis longus' anatomical structure or function. Thus, the correct choice accurately reflects the muscle's insertion and highlights its role in foot mechanics.