The adult acquired flatfoot (AAF) 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. Although the posterior tibialis tendon plays a significant role, this pathology has recently been recognized as involving failure of other interosseous ligaments, such as the spring ligament. Due to the complexity of this pathology, posterior tibial tendon dysfunction (PTTD) is now referred to as adult acquired flatfoot. Severe flatfoot associated with AAF can lead to other problems, such as plantar fascial tension, tendon pain, rearfoot subluxation, and ankle osteoarthritis.
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.
Initially, flatfoot deformity may not present with any symptoms. However, overtime as the tendon continues to function in an abnormal position, people with fallen arches will begin to have throbbing or sharp pain along the inside of the arch. Once the tendon and soft tissue around it elongates, there is no strengthening exercises or mechanism to shorten the tendon back to a normal position. Flatfoot can also occur in one or both feet. If the arch starts to slowly collapse in one foot and not the other, posterior tibial dysfunction (PTTD) is the most likely cause. People with flatfoot may only have pain with certain activities such as running or exercise in the early phase of PTTD. Pain may start from the arch and continue towards the inside part of the foot and ankle where the tendon courses from the leg. Redness, swelling and increased warmth may also occur. Later signs of PTTD include pain on the outside of the foot from the arch collapsing and impinging other joints. Arthritic symptoms such as painful, swollen joints in the foot and ankle may occur later as well due to the increased stress on the joints from working in an abnormal position for a long period of time.
The diagnosis of posterior tibial tendon dysfunction and AAFD is usually made from a combination of symptoms, physical exam and x-ray imaging. The location of pain, shape of the foot, flexibility of the hindfoot joints and gait all may help your physician make the diagnosis and also assess how advanced the problem is.
Non surgical Treatment
Options range from shoe inserts, orthotics, bracing and physical therapy for elderly and/or inactive patients to reconstructive surgical procedures in those wishing to remain more active. These treatments restore proper function and alignment of the foot by replacing the damaged muscle tendon unit with an undamaged, available and expendable one, lengthening the contracted Achilles tendon and realigning the Os Calcis, or heel bone, while preserving the joints of the hindfoot. If this condition is not recognized before it reaches advanced stages, a fusion of the hindfoot or even the ankle is necessary. Typically this is necessary in elderly individuals with advanced cases that cannot be improved with bracing.
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. Surgical treatment may include repairing the tendon, tendon transfers, realigning the bones of the foot, joint fusions, or both. Dr. Piccarelli will determine the best approach for your specific case. A variety of surgical techniques is available to correct flexible flatfoot. Your case may require one procedure or a combination of procedures. All of these surgical techniques are aimed at relieving the symptoms and improving foot function. Among these procedures are tendon transfers or tendon lengthening procedures, realignment of one or more bones, or insertion of implant devices. Whether you have flexible flatfoot or PTTD, to select the procedure or combination of procedures for your particular case, Dr. Piccarelli will take into consideration the extent of your deformity based on the x-ray findings, your age, your activity level, and other factors. The length of the recovery period will vary, depending on the procedure or procedures performed.