Posterior tibial tendon dysfunction (PTTD) is an inflammation and / or overstretching of the posterior tibial tendon in the foot. An important function of the posterior tibial tendon is to help support the arch. But in PTTD, the tendon?s ability to perform that job is impaired, often resulting in a flattening of the foot. PTTD is often called ?adult-acquired flatfoot? because it is the most common type of flatfoot developed during adulthood. Although this condition typically occurs in only one foot, some people may develop it in both feet. PTTD is usually progressive, which means it will keep getting worse-especially if it isn?t treated early. This differs from flexible flatfoot because flexible flatfoot typically begins in childhood or adolescence and continues into adulthood. It usually occurs in both feet and generally progresses in severity throughout the adult years. As the deformity worsens, the soft tissues (tendons and ligaments) of the arch may stretch or tear and become inflamed. The term ?flexible? means that while the foot is flat when standing (weight bearing), the arch returns when not standing. In the early stages of flexible flatfoot arthritis is not restricting motion of the arch and foot, but in the later stages arthritis may develop to such a point that the arch and foot become stiff.
As the name suggests, adult-acquired flatfoot occurs once musculoskeletal maturity is reached, and it can present for a number of reasons, though one stands out among the others. While fractures, dislocations, tendon lacerations, and other such traumatic events do contribute to adult-acquired flatfoot as a significant lower extremity disorder, as mentioned above, damage to the posterior tibial tendon is most often at the heart of adult-acquired flatfoot. One study further elaborates on the matter by concluding that ?60% of patients [presenting with posterior tibial tendon damage and adult-acquired flatfoot] were obese or had diabetes mellitus, hypertension, previous surgery or trauma to the medial foot, or treatment with steroids?.
The first stage represents inflammation and symptoms originating from an irritated posterior tibial tendon, which is still functional. Stage two is characterized by a change in the alignment of the foot noted on observation while standing (see above photos). The deformity is supple meaning the foot is freely movable and a ?normal? position can be restored by the examiner. Stage two is also associated with the inability to perform a single-leg heel rise. The third stage is dysfunction of the posterior tibial tendon is a flatfoot deformity that becomes stiff because of arthritis. Prolonged deformity causes irritation to the involved joints resulting in arthritis. The fourth phase is a flatfoot deformity either supple (stage two) or stiff (stage 3) with involvement of the ankle joint. This occurs when the deltoid ligament, the major supporting structure on the inside of the ankle, fails to provide support. The ankle becomes unstable and will demonstrate a tilted appearance on X-ray. Failure of the deltoid ligament results from an inward displacement of the weight bearing forces. When prolonged, this change can lead to ankle arthritis. The vast majority of patients with acquired adult flatfoot deformity are stage 2 by the time they seek treatment from a physician.
Examination by your foot and ankle specialist can confirm the diagnosis for most patients. An ultrasound exam performed in the office setting can evaluate the status of the posterior tibial tendon, the tendon which is primarily responsible for supporting the arch structure of the foot.
Non surgical Treatment
Depending on the stage of the deformity and patient?s functional goals, various treatment options are available. Some patients improve with conservative care which includes rest and immobilization, shoe modifications, orthoses and bracing, or physical therapy. Surgery might be warranted for advanced stages of the condition. Often a combination of procedures including tendon and muscle augmentation, tendon transfers, realigning of bones or fusion of certain joints might be necessary in more advanced cases. Your doctor will evaluate and recommend an individualized plan of care with your specific needs in mind.
For more chronic flatfoot pain, surgical intervention may be the best option. Barring other serious medical ailments, surgery is a good alternative for patients with a serious problem. There are two surgical options depending on a person?s physical condition, age and lifestyle. The first type of surgery involves repair of the PTT by transferring of a nearby tendon to help re-establish an arch and straighten out the foot. After this surgery, patients wear a non-weight bearing support boot for four to six weeks. The other surgery involves fusing of two or three bones in the hind foot below the ankle. While providing significant pain relief, this option does take away some hind foot side-to-side motion. Following surgery, patients are in a cast for three months. Surgery is an effective treatment to address adult-acquired flatfoot, but it can sometimes be avoided if foot issues are resolved early. That is why it is so important to seek help right away if you are feeling ankle pain. But perhaps the best way to keep from becoming flatfooted is to avoid the risk factors altogether. This means keeping your blood pressure, weight and diabetes in check.