Acquired adult flatfoot deformity (AAFD) is a progressive flattening of the arch of the foot that occurs as the posterior tibial tendon becomes insufficient. It has many other names such posterior tibial tendon dysfunction, posterior tibial tendon insufficiency and dorsolateral peritalar subluxation. This problem may progress from early stages with pain along the posterior tibial tendon to advanced deformity and arthritis throughout the hindfoot and ankle.
Posterior tibial tendon dysfunction is the most common cause of acquired adult flatfoot. Sometimes this can be a result of specific trauma, but usually the tendon becomes injured from wear and tear over time. This is more prevalent in individuals with an inherited flat foot but excessive weight, age, and level of activity are also contributing factors.
At first you may notice pain and swelling along the medial (big toe) side of the foot. This is where the posterior tibialis tendon travels from the back of the leg under the medial ankle bone to the foot. As the condition gets worse, tendon failure occurs and the pain gets worse. Some patients experience pain along the lateral (outside) edge of the foot, too. You may find that your feet hurt at the end of the day or after long periods of standing. Some people with this condition have trouble rising up on their toes. They may be unable to participate fully in sports or other recreational activities.
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
Conservative treatment also depends on the stage of the disease. Early on, the pain and swelling with no deformity can be treated with rest, ice, compression, elevation and non-steroidal anti-inflammatory medication. Usually OTC orthotic inserts are recommended with stability oriented athletic shoes. If this fails or the condition is more advanced, immobilization in a rigid walking boot is recommended. This rests the tendon and protects it from further irritation, attenuation, or tearing. If symptoms are greatly improved or eliminated then the patient may return to a supportive shoe. To protect the patient from reoccurrence, different types of devices are recommended. The most common device is orthotics. Usually custom-made orthotics are preferable to OTC. They are reserved for early staged PTTD. Advanced stages may require a more aggressive type orthotic or an AFO (ankle-foot orthosis). There are different types of AFO's. One type has a double-upright/stirrup attached to a footplate. Another is a gauntlet-type with a custom plastic interior surrounded be a lace-up leather exterior. Both require the use of a bulky type athletic or orthopedic shoes. Patient compliance is always challenging with these larger braces and shoes.
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.