Tibialis Posterior Tendinopathy (Tendinitis, Dysfunction)
Tibialis posterior is one of the most important tendons in the foot. The muscle belly lies in the calf and the tendon passes just behind the medial (inner) bony prominence of the ankle. Its role is to hold up the arch of the foot and stabilize the midfoot on the hindfoot. Tendinopathy (disease) of tibialis posterior is a common cause of acquired or deteriorating flatfoot in adults, particularly in middle age and beyond. The causes of tibialis posterior tendinopathy are not fully understood but pre-existing flatfoot, female gender, and overuse often play a role. Occasionally it can follow traumatic injury to the foot.
Early features of tibilais posterior tendinopathy include pain and swelling on the medial (inner) side of the ankle and hindfoot. At this stage the tendon, although diseased, is still working, so there is no change in the overall architecture of the foot. If untreated the condition usually progresses until the tendon fails. At this point the arch of the foot starts to fall and the heel tilts over to the side. Paradoxically the pain may reduce considerably at this stage because the tendon has given up altogether. For a while the foot deformity remains flexible and correctable, but eventually arthritis of the hindfoot joints develops, pain increases and the deformity becomes fixed.
In the early stages tibialis posterior tendinopathy can be treated with medial arch supports (insoles), physiotherapy and a period of rest. If the function of the tendon has become compromised it can be restored with surgery in the form of a realignment of the heel bone and transfer of another tendon, such as flexor digitorum longus, to reinforce it. Once arthritis has supervened, the architecture and stability of the foot can still be restored but this requires surgery in the form of a triple fusion which entails a protracted recovery period and leaves the hindfoot stable but stiff.
Tibilais posterior tendinopathy is a progressive condition, treatment of which is easiest and least invasive in the early stages. If it is suspected an opinion from an Orthopaedic Foot and Ankle Specialist should be sought at an early stage.