Tibialis posterior dysfunction
Tibialis posterior dysfunction is a severe disease of the tendon of the tibialis posterior muscle in the lower leg-foot region. As damage to the tibialis posterior tendon progresses, it causes increasing dysfunction. In the further course of the disease, this leads, in most cases, to a planovalgus deformity(flat foot).
The etiology of the dysfunction is not yet fully understood. However, it is clear that the damage to the tibialis posterior tendon has almost exclusively a degenerative background and occurs three times more frequently in women than in men. Overweight and hypertension have a favourable effect on the disease.
The pathology of the disease is documented with the help of sonography and MRI. The severity of the deformity is determined by X-ray posture diagnostics. In the next step, muscle strength testing and clinical function tests are used to determine the dysfunction of the foot. Since tibialis posterior dysfunction is a stadial disease, it is then classified into one of three phases according to Johnson & Strom (1989), depending on the course of the disease. Newer diagnostic approaches include pedobarography to analyze the gait pattern in order to determine the classification into the respective stage as accurately as possible.
Despite the progressive course of the disease, conservative treatment is usually the appropriate approach initially. The basis of conservative treatment is the sparing of the foot; weight-bearing should only take place if it is pain-free. In further steps, physiotherapeutic measures and systemic antiphlogistic therapy are usually recommended. Passive support of the longitudinal arch of the foot by means of insoles is also useful, especially to cushion the heel.
Between the three stages according to Johnson & Strom 1989, different surgical measures are taken. In stage I, surgical exploration is first performed with an incision in the skin and inflamed tissue is removed. Furthermore, dead tissue within the tendon is excised by means of a tenotomy. In stage II, if the course of the disease permits, a tendon transfer is performed. In this case, healthy tendons are used to reconstruct diseased tendons. For advanced cases in stage II and stage III, bony interventions in the form of osteotomies are additionally required. In particularly severe cases, arthrodesis is performed to improve the condition.
- Andreas B. Imhoff, Hans Zollinger-Kies: Fusschirurgie. Georg Thieme Verlag 2004, ISBN 9783131238511, pp. 192-198.