The tibialis posterior tendon runs behind the inner bone of the ankle; an injury or dysfunction of this muscle leads to loss of strength and and the collapsing of the medial arch of the foot; affecting biomechanical disorders such as plantar drop (of the talus and other secondary deformities) (Guelfi et al., 2017).
Tibialis posterior functions as a dynamic stabilizer of the medial longitudinal arch and the main inverter of the midfoot (rotating inwards) (Guelfi et al., 2017).
Problems with the tibialis posterior tendon are usually associated with flatfoot deformity and a collapsing medial longitudinal arch in combination with a progressive loss of strength of the tibialis posterior tendon (Guelfi et al., 2017).Injury is caused when the tendon is overused or overstretched, tibialis posterior acts to control movement in the foot and form the arch of the foot. Activities like running and jumping can stress this tendon causing inflammation.
Management of this injury involves following the RICE regime, correction of abnormal foot biomechanics and analysing gait and muscle balance.
Guelfi M. et al., 2017, Anatomy, pathophysiology and classification of posterior tibial tendon dysfunction, European Review for Medical and Pharmacological Sciences, 21; pp: 13-19