Adult acquired flatfoot deformity (AAFD or AAF) is a progressive, symptomatic deformity resulting from gradual stretch of the posterior tibial tendon as well as other ligaments supporting the arch of the foot. AAFD develops after skeletal maturity, May also be referred to as posterior tibial tendon dysfunction (PTTD), although due to the complexity of the disorder AAFD is more appropriate. Significant ligamentous rupture occurs as the deformity progresses. Involved ligaments include the spring ligament, the superficial deltoid ligament, the plantar fascia, and the long and short plantar ligaments. Unilateral AAFD is more common than bilateral AAFD.
Flat feet causes greater pressure on the posterior tibial tendon than normal. As the person with flat feet ages, the muscles, tendons and ligaments weaken. Blood supplies diminish as arteries narrow. These conditions are magnified for obese patients because of their increased weight and atherosclerosis. Finally, the tendon gives out or tears. Most of the time, this is a slow process. Once the posterior tibial tendon and ligaments stretch, body weight causes the bones of the arch to move out of position. The foot rotates inward (pronation), the heel bone is tilted to the inside, and the arch appears collapsed. In some cases, the deformity progresses until the foot dislocates outward from the ankle joint.
Posterior tibial tendon insufficiency is divided into stages by most foot and ankle specialists. In stage I, there is pain along the posterior tibial tendon without deformity or collapse of the arch. The patient has the somewhat flat or normal-appearing foot they have always had. In stage II, deformity from the condition has started to occur, resulting in some collapse of the arch, which may or may not be noticeable. The patient may feel it as a weakness in the arch. Many patients initially present in stage II, as the ligament failure can occur at the same time as the tendon failure and therefore deformity can already be occurring as the tendon is becoming symptomatic. In stage III, the deformity has progressed to the extent where the foot becomes fixed (rigid) in its deformed position. Finally, in stage IV, deformity occurs at the ankle in addition to the deformity in the foot.
Your podiatrist is very familiar with tendons that have just about had enough, and will likely be able to diagnose this condition by performing a physical exam of your foot. He or she will probably examine the area visually and by feel, will inquire about your medical history (including past pain or injuries), and may also observe your feet as you walk. You may also be asked to attempt standing on your toes. This may be done by having you lift your ?good? foot (the one without the complaining tendon) off the ground, standing only on your problem foot. (You may be instructed to place your hands against the wall to help with balance.) Then, your podiatrist will ask you to try to go up on your toes on the bad foot. If you have difficulty doing so, it may indicate a problem with your posterior tibial tendon. Some imaging technology may be used to diagnose this condition, although it?s more likely the doctor will rely primarily on a physical exam. However, he or she may order scans such as an MRI or CT scan to look at your foot?s interior, and X-rays might also be helpful in a diagnosis.
Non surgical Treatment
Flatfoot can be treated with a variety of methods, including modified shoes, orthotic devices, a brace or cast, anti-inflammatory medications or limited steroid injections, rest, ice, and physical therapy. In severe cases, surgery may be necessary.
A new type of surgery has been developed in which surgeons can re-construct the flat foot deformity and also the deltoid ligament using a tendon called the peroneus longus. A person is able to function fully without use of the peroneus longus but they can also be taken from deceased donors if needed. The new surgery was performed on four men and one woman. An improved alignment of the ankle was still evident nine years later, and all had good mobility 8 to 10 years after the surgery. None had developed arthritis.