Where does the fibularis longus insert into the foot structure?

• A. Tarsal I and dorsal aspect of metatarsals II-V
• B. Tarsal IV and plantar aspect of metatarsals II-V
• C. Calcaneal tuberosity
• D. Distal phalanges I-V

Answer: (B)

The fibularis longus, also known as peroneus longus, is a muscle located in the lateral compartment of the leg. One of its primary functions includes eversion and plantarflexion of the foot. The tendon of the fibularis longus travels beneath the foot, specifically passing behind the lateral malleolus and then running beneath the foot to insert onto the plantar aspect of the first metatarsal and the medial cuneiform bone.

The correct answer indicates that the fibularis longus inserts into the tarsal IV and the plantar aspect of the metatarsals II-V, which is consistent with its anatomical pathway and functional roles in maintaining balance on the foot. This insertion is essential for the muscle's role in eversion and stabilization during weight-bearing activities.

In contrast, the other options do not accurately reflect the anatomical insertion of the fibularis longus. For instance, inserting into tarsal I and the dorsal aspects of metatarsals II-V would suggest a different functional implication and pathway that does not correspond with the muscle's trajectory. Similarly, the calcaneal tuberosity serves as an attachment for different structures involved in supporting the heel, and inserting into the distal phalanges I