Plantar fasciitis represents inflammation of the plantar fascia. 

It is a very common cause of pain or discomfort in often very active patients like runners or dancers. It appears after long-term repetitive movements. Apart from mecanical factors the causes can be degenerative or systemic such as a variety of reumatic diseases. The pain is located on the heel medially and is worse when stepping on heel. Conservative therapy is the preferred treatement. Plantar fascie are arranged to limit tangential mobility of the skin,  to hold down muscles and tendons in the sole and digits and to facilitate their excursion along the most functionally advantegous routes. It also helps to reduce compression of plantar and digital arteries and nerves. Parts of deep fascia inferior to the plantar structures are collectively the plantar aponeurosis. Only the central part is entirely aponeurotic, sometimes the name is reserved for this (2). Plantar aponeurosis is triangular structure of densly compacted collagen fibres as is presented in Fig. 1. It is 1,5 - 2 cm wide and 2-4 mm thin. It has two parts: central part is covering m. flexor digitorum brevis tendon, lateral part m. abductor digiti minimi. The central part may recive contribution from the Achilles tendon (3).