Which Are The Key Causes Of Posterior Tibial Tendon Dysfunction (PTTD) ?

Overview
PTTD is a common condition treated by foot and ankle specialists. Although there is a role for surgical treatment of PTTD, conservative care often can prevent or delay surgical intervention. Decreasing inflammation and stabilizing the affected joints associated with the posterior tibial tendon can decrease pain and increase functional levels. With many different modalities available, aggressive nonoperative methods should be considered in the treatment of PTTD, including early immobilization, the use of long-term bracing, physical therapy, and anti-inflammatory medications. If these methods fail, proper evaluation and work-up for surgical intervention should be employed.

Causes
A person with flat feet has greater load placed on the posterior tibial tendon which is the main tendon unit supporting up the arch of the foot. Throughout life, aging leads to decreased strength of muscles, tendons and ligaments. The blood supply diminishes to tendons with aging as arteries narrow. Heavier, obese patients have more weight on the arch and have greater narrowing of arteries due to atherosclerosis. In some people, the posterior tibial tendon finally gives out or tears. This is not a sudden event in most cases. Rather, it is a slow, gradual stretching followed by inflammation and degeneration of the tendon. Once the posterior tibial tendon stretches, the ligaments of the arch stretch and tear. The bones of the arch then move out of position with body weight pressing down from above. The foot rotates inward at the ankle in a movement called pronation. The arch appears collapsed, and the heel bone is tilted to the inside. The deformity can progress until the foot literally dislocates outward from under the ankle joint.

Symptoms
The symptoms of PTTD may include pain, swelling, a flattening of the arch, and an inward rolling of the ankle. As the condition progresses, the symptoms will change. For example, when PTTD initially develops, there is pain on the inside of the foot and ankle (along the course of the tendon). In addition, the area may be red, warm, and swollen. Later, as the arch begins to flatten, there may still be pain on the inside of the foot and ankle. But at this point, the foot and toes begin to turn outward and the ankle rolls inward. As PTTD becomes more advanced, the arch flattens even more and the pain often shifts to the outside of the foot, below the ankle. The tendon has deteriorated considerably and arthritis often develops in the foot. In more severe cases, arthritis may also develop in the ankle.

Diagnosis
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
Flatfoot deformity can be treated conservatively or with surgical intervention depending on the severity of the condition. When people notice their arches flattening, they should immediately avoid non-supportive shoes such as flip-flops, sandals or thin-soled tennis shoes. Theses shoes will only worsen the flatfoot deformity and exacerbate arch pain. Next, custom orthotics are essential for people with collapsed arches. Over-the-counter insoles only provide cushion and padding to the arch, whereas custom orthotics are fabricated to specifically fit the patient?s foot and provide support in the arch where the posterior tibial tendon is unable to anymore. Use of custom orthotics in the early phases of flatfoot or PTTD can prevent worsening of symptoms and prevent further attenuation or injury to the posterior tibial tendon. In more severe cases of flatfoot deformity an ankle foot orthosis (AFO) such as a Ritchie brace is needed. This brace provides more support to the arch and hindfoot rather than an orthotic but can be bulky in normal shoegear. Additional treatment along with use of custom orthotics is use of non-steroidal anti-inflammatories (NSAIDS) such as Advil, Motrin, or Ibuprofen which can decrease inflammation to the posterior tibial tendon. If pain is severe, the patient may need to be placed in a below the knee air walker boot for several weeks which will allow the tendon to rest and heal, especially if a posterior tibial tendon tear is noted on MRI.

Surgical Treatment
If conservative treatment fails surgical intervention is offered. For a Stage 1 deformity a posterior tibial tendon tenosynovectomy (debridement of the tendon) or primary repair may be indicated. For Stage 2 a combination of Achilles lengthening with bone cuts, calcaneal osteotomies, and tendon transfers is common. Stage 2 flexible PTTD is the most common stage patients present with for treatment. In Stage 3 or 4 PTTD isolated fusions, locking two or more joints together, maybe indicated. All treatment is dependent on the stage and severity at presentation with the goals and activity levels of the patient in mind. Treatment is customized to the individual patient needs.