Posterior tibial tendon dysfunction is one of several terms to describe a painful, progressive flatfoot deformity in adults. Other terms include posterior tibial tendon insufficiency and adult acquired flatfoot. The term adult acquired flatfoot is more appropriate because it allows a broader recognition of causative factors, not only limited to the posterior tibial tendon, an event where the posterior tibial tendon looses strength and function. The adult acquired flatfoot is a progressive, symptomatic (painful) deformity resulting from gradual stretch (attenuation) of the tibialis posterior tendon as well as the ligaments that support the arch of the foot.
Adult flatfoot typically occurs very gradually. If often develops in an obese person who already has somewhat flat feet. As the person ages, the tendons and ligaments that support the foot begin to lose their strength and elasticity.
Most people will notice mild to extreme pain in their feet. Below outlines some signs and symptoms of AAFD. Trouble walking or standing for any duration. Pain and swelling on the inside of the ankle. Bump on the bottom of the foot. Ulcer or wound developing on the outer aspects of foot.
Observe forefoot to hindfoot alignment. Do this with the patient sitting and the heel in neutral, and also with the patient standing. I like to put blocks under the forefoot with the heel in neutral to see how much forefoot correction is necessary to help hold the hindfoot position. One last note is to check all joints for stiffness. In cases of prolonged PTTD or coalition, rigid deformity is present and one must carefully check the joints of the midfoot and hindfoot for stiffness and arthritis in the surgical pre-planning.
Non surgical Treatment
In the early stages, simple pre-fabricated orthotics can help improve the heel position to reduce the mechanical load which is contributing to the symptoms. In advanced stages or long term orthotic use, a plaster of paris or foam box cast can be taken and specific bespoke orthotics manufactured. If the condition develops further a AFO (ankle foot orthotic) may be necessary for greater control. In more advanced stages of symptomatic Adult Acquired flat feet, where the conservative methods of treatment have failed there are various forms of surgery available depending upon the root cause of the issue and severity.
Good to excellent results for more than 80% of patients have been reported at five years’ follow up for the surgical interventions recommended below. However, the postoperative recovery is a lengthy process, and most surgical procedures require patients to wear a plaster cast for two to three months. Although many patients report that their function is well improved by six months, in our experience a year is required to recover truly and gain full functional improvement after the surgery. Clearly, some patients are not candidates for such major reconstructive surgery.