Fibularis longus muscle

Last revised by Yahya Baba on 6 Feb 2023

The fibularis longus muscle (also known as peroneus longus muscle) is one of the muscles of the lateral compartment of the leg.

  • from the head and upper two thirds of the peroneal aspect of the shaft of the fibula and intermuscular septum

  • the fibularis longus tendon passes down the leg superficial to the fibularis brevis muscle and does not touch the lateral malleolus due to the intervening brevis tendon

  • both fibular tendons then course anteriorly toward the fibular trochlea of the lateral calcaneum, at which point the longus tendon runs inferiorly to the peroneal trochlea

  • from this point, the tendon passes into the plantar compartment of the foot and contacts the posterior ridge of the groove on the cuboid bone

  • occasionally the fibrocartilaginous sesamoid, which lies within the longus tendon at this point, may ossify

  • runs deep to the long plantar ligament 

  • finally, the peroneus longus tendon runs anteromedially across the sole and inserts into the fibular aspect of the base of the first metatarsal and the adjacent aspect of the medial cuneiform bone

  • vena comitantes and short saphenous vein

  • superficial peroneal nerve (L5, S1)

  • everts foot (in tandem with the fibularis brevis muscle)

  • weak plantarflexion of the foot

  • provides support for the lateral longitudinal arch and transverse arches

  • duplex belly fibularis longus 

  • fusion of fibularis brevis and fibularis longus

  • os peroneum

ADVERTISEMENT: Supporters see fewer/no ads

Cases and figures

  • Figure 1: Gray's anatomy illustration
    Drag here to reorder.
  • Figure 2: Gray's anatomy illustration
    Drag here to reorder.
  • Figure 3: peroneal tendons
    Drag here to reorder.
  • Figure 4: plantar ligaments of the foot (Gray's illustration)
    Drag here to reorder.
  • Updating… Please wait.

     Unable to process the form. Check for errors and try again.

     Thank you for updating your details.