Adult acquired flatfoot deformity (AAFD) is a painful, chronic condition found most often in women between the ages of 40 and 60. AAFD occurs when the soft tissues of the foot are overstretched and torn, causing the arch to collapse. Flatfoot deformities may also be caused by a foot fracture, or may result from long-term arthritis. Once the posterior tibial tendon-the tendon unit that holds up the arch-loses its function, the foot becomes ?flat? as the bones spread out of position during weight bearing. Without an AAFD repair, the condition may progress until the affected foot becomes entirely rigid and quite painful.
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.
Pain and swelling behind the inside of your ankle and along your instep. You may be tender behind the inner ankle where the posterior tibial tendon courses and occasionally get burning, shooting, tingling or stabbing pain as a result of inflammation of the nerve inside the tarsal tunnel. Difficulty walking, the inability to walk long distances and a generalised ache while walking even short distances. This may probably become more pronounced at the end of each day. Change in foot shape, sometimes your tendon stretches out, this is due to weakening of the tendon and ligaments. When this occurs, the arch in your foot flattens and a flatfoot deformity occurs, presenting a change in foot shape. Inability to tip-toe, a way of diagnosing Posterior Tibial Tendon Dysfunction is difficulty or inability to ?heel rise? (stand on your toes on one foot). Your tibialis posterior tendon enables you to perform this manoeuvre effectively. You may also experience pain upon attempting to perform a heel rise.
The adult acquired flatfoot, secondary to posterior tibial tendon dysfunction, is diagnosed in a number of ways with no single test proven to be totally reliable. The most accurate diagnosis is made by a skilled clinician utilizing observation and hands on evaluation of the foot and ankle. Observation of the foot in a walking examination is most reliable. The affected foot appears more pronated and deformed compared to the unaffected foot. Muscle testing will show a strength deficit. An easy test to perform in the office is the single foot raise. A patient is asked to step with full body weight on the symptomatic foot, keeping the unaffected foot off the ground. The patient is then instructed to "raise up on the tip toes" of the affected foot. If the posterior tibial tendon has been attenuated or ruptured, the patient will be unable to lift the heel off the floor and rise onto the toes. In less severe cases, the patient will be able to rise on the toes, but the heel will not be noted to invert as it normally does when we rise onto the toes. X-rays can be helpful but are not diagnostic of the adult acquired flatfoot. Both feet - the symptomatic and asymptomatic - will demonstrate a flatfoot deformity on x-ray. Careful observation may show a greater severity of deformity on the affected side.
Non surgical Treatment
There are many non-surgical options for the flatfoot. Orthotics, non-custom braces, shoe gear changes and custom braces are all options for treatment. A course of physical therapy may be prescribed if tendon inflammation is part of the problem. Many people are successfully treated with non-surgical alternatives.
Although non-surgical treatments can successfully manage the symptoms, they do not correct the underlying problem. It can require a life-long commitment to wearing the brace during periods of increased pain or activity demands. This will lead a majority of patients to choose surgical correction of the deformity, through Reconstructive Surgery. All of the considerations that were extremely important during the evaluation stage become even more important when creating a surgical plan. Generally, a combination of procedures are utilized in the same setting, to allow full correction of the deformity. Many times, this can be performed as a same-day surgery, without need for an overnight hospital stay. However, one or two day hospital admissions can be utilized to help manage the post-operative pain. Although the recovery process can require a significant investment of time, the subsequent decades of improved function and activity level, as well as decreased pain, leads to a substantial return on your investment.