Adult Acquired Flatfoot (Posterior Tibial Tendon Dysfunction) is a painful, progressive deformity in adults. It results from a gradual stretch (attenuation) of the tibialis posterior tendon and the ligaments that support your foot’s arch. This stretching causes the tendon to lose strength and function. Many people have flat feet and do not experience pain. However, pain occurs with Adult Acquired Flatfoot because the tendons and ligaments have been torn. Once the vital ligaments and posterior tibial tendon are lost, there is no longer anything holding the arch of the foot in place.
As discussed above, many health conditions can create a painful flatfoot. Damage to the posterior tibial tendon is the most common cause of AAFD. The posterior tibial tendon is one of the most important tendons of the leg. It starts at a muscle in the calf, travels down the inside of the lower leg and attaches to the bones on the inside of the foot. The main function of this tendon is to hold up the arch and support your foot when you walk. If the tendon becomes inflamed or torn, the arch will slowly collapse. Women and people over 40 are more likely to develop problems with the posterior tibial tendon. Other risk factors include obesity, diabetes, and hypertension. Having flat feet since childhood increases the risk of developing a tear in the posterior tibial tendon. In addition, people who are involved in high impact sports, such as basketball, tennis, or soccer, may have tears of the tendon from repetitive use. Inflammatory arthritis, such as rheumatoid arthritis, can cause a painful flatfoot. This type of arthritis attacks not only the cartilage in the joints, but also the ligaments that support the foot. Inflammatory arthritis not only causes pain, but also causes the foot to change shape and become flat. The arthritis can affect the back of the foot or the middle of foot, both of which can result in a fallen arch.
In many cases, adult flatfoot causes no pain or problems. In others, pain may be severe. Many people experience aching pain in the heel and arch and swelling along the inner side of the 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
Although AAF is not reversible without surgery, appropriate treatment should address the patient?s current symptoms, attempt to reduce pain, and allow continued ambulation. In the early stages, orthotic and pedorthic solutions can address the loss of integrity of the foot?s support structures, potentially inhibiting further destruction.3-5 As a general principle, orthotic devices should only block or limit painful or destructive motion without reducing or restricting normal motion or muscle function. Consequently, the treatment must match the stage of the deformity.
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.