Peroneus longus muscle originates from the fibula and superior tibiofibular joint and inserts into the plantar aspect of base 1st metatarsal and medial cuneiform, passing deep to long plantar ligament.

Its function is t plantar flex and evert the foot. To support the lateral longitudinal and transverse arches.

Nerve supply is via the superficial peroneal nerve.

This patient presented with pain in the plantar aspect of her foot. This case demonstrates the necessity of ensuring a good review of the tendon along its entirety. 

I'd like to thank Dr H Patel for supervising, contributing and assisting me with this case.