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.
Overuse of the posterior tibial tendon is often the cause of PTTD. In fact, the symptoms usually occur after activities that involve the tendon, such as running, walking, hiking, or climbing stairs.
As different types of flatfoot have different causes, the associated symptoms can be different for different people. Some generalized symptoms are listed. Pain along the course of the posterior tibial tendon which lies on the inside of the foot and ankle. This can be associated with swelling on the inside of the ankle. Pain that is worse with activity. High intensity or impact activities, such as running and jumping, can be very difficult. Some patients can have difficulty walking or even standing for long periods of time and may experience pain at the inside of the ankle and in the arch of the foot. Feeling like one is ?dragging their foot.? When the foot collapses, the heel bone may shift position and put pressure on the outside ankle bone (fibula). This can cause pain in the bones and tendons in the outside of the ankle joint. Patients with an old injury or arthritis in the middle of the foot can have painful, bony bumps on the top and inside of the foot. These make shoe wear very difficult. Sometimes, the bony spurs are so large that they pinch the nerves which can result in numbness and tingling on the top of the foot and into the toes. Diabetic patients may not experience pain if they have damage to their nerves. They may only notice swelling or a large bump on the bottom of the foot. The large bump can cause skin problems and an ulcer (a sore that does not heal) may develop if proper diabetic shoe wear is not used.
There are four stages of adult-acquired flatfoot deformity (AAFD). The severity of the deformity determines your stage. For example, Stage I means there is a flatfoot position but without deformity. Pain and swelling from tendinitis is common in this stage. Stage II there is a change in the foot alignment. This means a deformity is starting to develop. The physician can still move the bones back into place manually (passively). Stage III adult-acquired flatfoot deformity (AAFD) tells us there is a fixed deformity. This means the ankle is stiff or rigid and doesn???t move beyond a neutral (midline) position. Stage IV is characterized by deformity in the foot and the ankle. The deformity may be flexible or fixed. The joints often show signs of degenerative joint disease (arthritis).
Non surgical Treatment
What are the treatment options? In early stages an orthotic that caters for a medially deviated subtalar joint ac-cess. Examples of these are the RX skive, Medafeet MOSI device. Customised de-vices with a Kirby skive or MOSI adaptation will provide greater control than a prefabricated device. If the condition develops further a UCBL orthotic or an AFO (ankle foot orthotic) could be necessary for greater control. Various different forms of surgery are available depending upon the root cause of the issue and severity.
Good to excellent results for more than 80% of patients have been reported at five years’ follow up for the surgical interventions recommended below. However, the postoperative recovery is a lengthy process, and most surgical procedures require patients to wear a plaster cast for two to three months. Although many patients report that their function is well improved by six months, in our experience a year is required to recover truly and gain full functional improvement after the surgery. Clearly, some patients are not candidates for such major reconstructive surgery.