A common problem among the elderly and increasingly middle aged patients is collapsing arches, medically known as Adult Acquired Flat Foot Syndrome (AAF), or Posterior Tibial Tendon Dysfunction (PTTD). This is a progressive condition in which the arch of the foot collapses and the bones of the ankle and foot fall out of proper alignment.
A magnitude of foot problems develop as we age and many of these complaints begin about the age of 60. Among the most serious from a biomechanical standpoint is Adult Acquired Flat Foot Syndrome (AAF). Treated early enough, symptoms can be arrested or at least slowed. Untreated however, AAF becomes an extremely painful condition which ultimately affects the entire body and the patient’s lifestyle, as gait is significantly altered by the out-of-line foot and ankle. This malalignment can create pain, fatigue, and discomfort throughout the entire body.
As we age, many of our muscles, tendons, and ligaments lose their ability to stretch and support our bones. If you’ve ever discovered an old rubber band in the bottom of a drawer, you’ll get the idea – it’s more likely to snap than stretch. The Posterior Tibial Tendon, which attaches the calf muscle to the bones in the foot, is largely responsible for the support of your foot when walking, and to hold up the arch. With aging, overuse, or trauma, this tendon degenerates and loses its function, along with associated ligaments and joints on the inner side of the ankle and foot. Ligaments are responsible for holding bones in place, and when they fail, bones shift and deformity is the result. The deformity causes malalignment, which leads to more stress and failure of the ligaments, and a slow collapse of the arch which becomes debilitating in its later stages.
AAF is most frequently seen in women, especially those who start out with somewhat flat feet or a pronated (rolls inward) foot. These attributes place extra stress on the soft tissue structures, along with the posterior tibial tendon and the ligaments on the inner side of the foot. Other contributing factors are diabetes, obesity, rheumatoid arthritis, and hypertension. People who play high impact sports may also develop tears in the posterior tibial tendon, eventually leading to AAF.
Symptoms of PTTD/AAF
The symptoms of posterior tibial tendon deformity change considerably as the condition progresses. Initially, pain may be felt along the tendon’s path on the inside of the foot and ankle. This area may also be red, warm, and swollen. As the arch starts to flatten, in addition to pain, the foot and toes turn outward and the ankle rolls inward. As the arch flattens even more, the pain shifts to the outside of the foot, just below the ankle. Arthritis develops in the foot, and later may develop in the ankle, sometimes causing the ankle joint to lock.
Treatment of PTTD/AAF
Treatment of adult acquired flatfoot depends on the stage of the condition and its severity. Mild cases may only warrant rest, ice, and custom orthotics. Advanced cases may require immobilization, bracing, or even surgery. Early intervention by a podiatric surgeon is key to slowing the progression of PTTD.
At the onset of PTTD, a boot or brace is used to support the arch and relieve strain on the soft tissues, including the tendon. When pain has subsided, custom orthotics are used to reduce the stress on these tissues. However, as the arch has already fallen, the deformity may progress. If pain persists after these conservative measures, surgery to correct the deformity may be recommended.