The posterior tibialis muscle originates on the bones of the leg (tibia and fibula). This muscle then passes behind the medial (inside) aspect of the ankle and attaches to the medial midfoot as the posterior tibial tendon. The posterior tibial tendon serves to invert (roll inward) the foot and maintain the arch of the foot. This tendon plays a central role in maintaining the normal alignment of the foot and also in enabling normal gait (walking). In addition to tendons running across the ankle and foot joints, a number of ligaments span and stabilize these joints. The ligaments at the medial ankle can become stretched and contribute to the progressive flattening of the arch. Several muscles and tendons around the ankle and foot act to counter-balance the action of the posterior tibial tendon. Under normal circumstances, the result is a balanced ankle and foot with normal motion. When the posterior tibial tendon fails, the other muscles and tendons become relatively over-powering. These muscles then contribute to the progressive deformity seen with this disorder.
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.
Depending on the cause of the flatfoot, a patient may experience one or more of the different symptoms here. 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, can be very difficult. Some patients can have difficulty walking or even standing for long periods of time. When the foot collapses, the heel bone may shift position and put pressure on the outside ankle bone (fibula). This can cause pain on the outside of the ankle. Arthritis in the heel also causes this same type of pain. 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 shoewear very difficult. Occasionally, 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. Diabetics may only notice swelling or a large bump on the bottom of the foot. Because their sensation is affected, people with diabetes may not have any pain. The large bump can cause skin problems and an ulcer (a sore that does not heal) may develop if proper diabetic shoewear is not used.
Diagnostic testing is often used to diagnose the condition and help determine the stage of the disease. The most common test done in the office setting are weightbearing X-rays of the foot and ankle. These assess joint alignment and osteoarthritis. If tendon tearing or rupture is suspected, the gold standard test would be MRI. The MRI is used to check the tendon, surrounding ligament structures and the midfoot and hindfoot joints. An MRI is essential if surgery is being considered.
Non surgical Treatment
Conservative (nonoperative) care is advised at first. A simple modification to your shoe may be all that???s needed. Sometimes purchasing shoes with a good arch support is sufficient. For other patients, an off-the-shelf (prefabricated) shoe insert works well. The orthotic is designed specifically to position your foot in good alignment. Like the shoe insert, the orthotic fits inside the shoe. These work well for mild deformity or symptoms. Over-the-counter pain relievers or antiinflammatory drugs such as ibuprofen may be helpful. If symptoms are very severe, a removable boot or cast may be used to rest, support, and stabilize the foot and ankle while still allowing function. Patients with longer duration of symptoms or greater deformity may need a customized brace. The brace provides support and limits ankle motion. After several months, the brace is replaced with a foot orthotic. A physical therapy program of exercise to stretch and strengthen the foot and leg muscles is important. The therapist will also show you how to improve motor control and proprioception (joint sense of position). These added features help prevent and reduce injuries.
In cases of PTTD that have progressed substantially or have failed to improve with non-surgical treatment, surgery may be required. For some advanced cases, surgery may be the only option. Symptomatic flexible flatfoot conditions are common entities in both the adolescent and adult populations. Ligamentous laxity and equinus play a significant role in most adolescent deformities. Posterior tibial tendon dysfunction (PTTD) is the most common cause of adult acquired flatfoot. One should consider surgical treatment for patients who have failed nonoperative therapy and have advancing symptoms and deformities that significantly interfere with the functional demands of daily life. Isolated Joint Fusion. This technique is used for well reducible flat foot by limiting motion at one or two joints that are usually arthritic. The Evans Anterior Calcaneal Osteotomy. This is indicated for late stage II adult acquired flatfoot and the flexible adolescent flatfoot. This procedure will address midtarsal instability, restore the medial longitudinal arch and reduce mild hind foot valgus. The Posterior Calcaneal Displacement Osteotomy (PCDO). This technique is indicated for late stage I and early stage II PTTD with reducible Calcaneal valgus. This is often combined with a tendon transfer. A PCDO is also indicated as an adjunctive procedure in the surgical reconstruction of the severe flexible adolescent flatfoot. Soft tissue procedure. On their own these are not very effective but in conjunction with an osseous procedure, soft tissue procedures can produce good outcome. Common ones are tendon and capsular repair, tendon lengthening and transfer procedures. Flat foot correction requires lengthy post operative period and a lot of patience. Your foot may need surgery but you might simply not have the time or endurance to go through the rehab phase of this type of surgery. We will discuss these and type of procedures necessary for your surgery in length before we go further with any type of intervention.