The Extensor Hallucis tendon runs from the shin at the front of the lower leg to the big toe. It’s job is to lift the big toe up. In combination with the extensor digitorum muscles and peroneus tertius, it is an important dorsiflexor (lifting up the foot) in the ankle and toes, to control the forefoot during the swing phase during gait (Baxter, Porter and Schon, 2008).
Injury is caused by overuse of the tendon due to poor biomechanics or poor footwear.
Correction of the biomechanics will unload the tendon and allow the muscle to function normally again
Baxter D.E., Porter D.A. and Schon L., 2008, Baxter’s Foot and Ankle in Sport, Elsevier Health Science, P: 121