Adult flatfoot (adult acquired flatfoot) or posterior tibial tendon dysfunction
(PTTD) is a common
pathology presented to foot and ankle specialists. PTTD is characterized by a valgus (everted) hindfoot, flattening of the longitudinal arch of the foot (collapse) and abduction of the forefoot. This
is a progressive deformity that begins flexible and can become rigid over time. The posterior tibial tendon (PT) is one of the main supporting structures of the foot arch. Changes within this tendon
cause flattening of the foot. There are four stages of this deformity that begins flexible and progressives, with no treatment, to a rigid deformity and with time may involve the ankle joint.
Patients usually present with pain in the foot or ankle stating the ankle is rolling. Its also common for patients to state they have difficulty walking barefoot. Pain is exacerbated after physical
activities. Pain is usually isolated to the inside of the foot along the course of the PT tendon.
Causes of an adult acquired flatfoot may include Neuropathic foot (Charcot foot) secondary to Diabetes mellitus, Leprosy, Profound peripheral neuritis of any cause. Degenerative changes in the ankle,
talonavicular or tarsometatarsal joints, or both, secondary to Inflammatory arthropathy, Osteoarthropathy, Fractures, Acquired flatfoot resulting from loss of the supporting structures of the medial
longitudinal arch. Dysfunction of the tibialis posterior tendon Tear of the spring (calcaneoanvicular) ligament (rare). Tibialis anterior rupture (rare). Painful flatfoot can have other causes, such
as tarsal coalition, but as such a patient will not present with a change in the shape of the foot these are not included here.
Initially, flatfoot deformity may not present with any symptoms. However, overtime as the tendon continues to function in an abnormal position, people with fallen arches will begin to have throbbing
or sharp pain along the inside of the arch. Once the tendon and soft tissue around it elongates, there is no strengthening exercises or mechanism to shorten the tendon back to a normal position.
Flatfoot can also occur in one or both feet. If the arch starts to slowly collapse in one foot and not the other, posterior tibial dysfunction (PTTD) is the most likely cause. People with flatfoot
may only have pain with certain activities such as running or exercise in the early phase of PTTD. Pain may start from the arch and continue towards the inside part of the foot and ankle where the
tendon courses from the leg. Redness, swelling and increased warmth may also occur. Later signs of PTTD include pain on the outside of the foot from the arch collapsing and impinging other joints.
Arthritic symptoms such as painful, swollen joints in the foot and ankle may occur later as well due to the increased stress on the joints from working in an abnormal position for a long period of
In the early stages of dysfunction of the posterior tibial tendon, most of the discomfort is located medially along the course of the tendon and the patient reports fatigue and aching on the
plantar-medial aspect of the foot and ankle. Swelling is common if the dysfunction is associated with tenosynovitis. As dysfunction of the tendon progresses, maximum pain occurs laterally in the
sinus tarsi because of impingement of the fibula against the calcaneus. With increasing deformity, patients report that the shape of the foot changes and that it becomes increasingly difficult to
wear shoes. Many patients no longer report pain in the medial part of the foot and ankle after a complete rupture of the posterior tibial tendon has occurred; instead, the pain is located laterally.
If a fixed deformity has not occurred, the patient may report that standing or walking with the hindfoot slightly inverted alleviates the lateral impingement and relieves the pain in the lateral part
of the foot.
Non surgical Treatment
Initial treatment consists of supporting the medial longitudinal arch (running the length of the foot) to relieve strain on the medial soft tissues. The most effective way to relieve pain on the
tendon is to use a boot or brace, and once tenderness and pain has resolved, an orthotic device. A boot, brace, or orthotic has not been shown to correct or even prevent the progression of deformity.
Orthotics can alleviate symptoms and may slow the progression of deformity, particularly if mild. The deformity may progress despite orthotics.
If conservative treatment fails to provide relief of pain and disability then surgery is considered. Numerous factors determine whether a patient is a surgical candidate. They include age, obesity,
diabetes, vascular status, and the ability to be compliant with post-operative care. Surgery usually requires a prolonged period of nonweightbearing immobilization. Total recovery ranges from 3
months to one year. Clinical, x-ray, and MRI examination are all used to select the appropriate surgical procedure.