Over 60 Million Americans suffer from Adult Acquired Flatfoot (AAF), otherwise known as Posterior Tibial Tendon Dysfunction or PTTD. This condition generally occurs in adults from 40-65 years of age, and it usually only occurs in one foot, not both. The Posterior Tibial (PT) Tendon courses along the inside part of the ankle and underneath the arch of the foot. It is the major supporting structure for the arch. Over time, the tendon becomes diseased, from overuse, and starts to lose it's strength. As a result, the arch begins to collapse, placing further strain on the PT Tendon, leading to further decrease in tendon strength, which causes further collapse of the arch. This is described as a progressive deformity because it will generally get worse over time.
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.
Posterior tibial tendon insufficiency is divided into stages by most foot and ankle specialists. In stage I, there is pain along the posterior tibial tendon without deformity or collapse of the arch. The patient has the somewhat flat or normal-appearing foot they have always had. In stage II, deformity from the condition has started to occur, resulting in some collapse of the arch, which may or may not be noticeable. The patient may feel it as a weakness in the arch. Many patients initially present in stage II, as the ligament failure can occur at the same time as the tendon failure and therefore deformity can already be occurring as the tendon is becoming symptomatic. In stage III, the deformity has progressed to the extent where the foot becomes fixed (rigid) in its deformed position. Finally, in stage IV, deformity occurs at the ankle in addition to the deformity in the foot.
Clinicians need to recognize the early stage of this syndrome which includes pain, swelling, tendonitis and disability. The musculoskeletal portion of the clinical exam can help determine the stage of the disease. It is important to palpate the posterior tibial tendon and test its muscle strength. This is tested by asking patient to plantarflex and invert the foot. Joint range of motion is should be assessed as well. Stiffness of the joints may indicate longstanding disease causing a rigid deformity. A weightbearing examination should be performed as well. A complete absence of the medial longitudinal arch is often seen. In later stages the head of the talus bone projects outward to the point of a large "lump" in the arch. Observing the patient's feet from behind shows a significant valgus rotation of the heel. From behind, the "too many toes" sign may be seen as well. This is when there is abducution of the forefoot in the transverse plane allowing the toes to be seen from behind. Dysfunction of the posterior tibial tendon can be assessed by asking the patient to stand on his/her toes on the affected foot. If they are unable to, this indicates the disease is in a more advanced stage with the tendon possibly completely ruptured.
Non surgical Treatment
Because of the progressive nature of PTTD, early treatment is advised. If treated early enough, your symptoms may resolve without the need for surgery and progression of your condition can be arrested. In contrast, untreated PTTD could leave you with an extremely flat foot, painful arthritis in the foot and ankle, and increasing limitations on walking, running, or other activities. In many cases of PTTD, treatment can begin with non-surgical approaches that may include. Orthotic devices or bracing. To give your arch the support it needs, your foot and ankle surgeon may provide you with an ankle brace or a custom orthotic device that fits into the shoe. Immobilization. Sometimes a short-leg cast or boot is worn to immobilize the foot and allow the tendon to heal, or you may need to completely avoid all weight-bearing for a while. Physical therapy. Ultrasound therapy and exercises may help rehabilitate the tendon and muscle following immobilization. Medications. Nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen, help reduce the pain and inflammation. Shoe modifications. Your foot and ankle surgeon may advise changes to make with your shoes and may provide special inserts designed to improve arch support.
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. Your foot and ankle surgeon will determine the best approach for you.