What Causes Posterior Tibial Tendon Dysfunction (PTTD) ?
OverviewAdult-acquired flatfoot is a challenging condition to treat. It is defined as a symptomatic, progressive deformity of the foot caused by loss of supportive structures of the medial arch. It is becoming increasingly frequent with the aging population and the obesity epidemic. Patients commonly try to lose weight by exercising to improve the condition. This often leads to worsening of symptoms and progression of the disorder. Early recognition of this complex disorder is essential, if chronic pain and surgery are to be avoided.CausesFlat 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.SymptomsThe symptom most often associated with AAF is PTTD, but it is important to see this only as a single step along a broader continuum. The most important function of the PT tendon is to work in synergy with the peroneus longus to stabilize the midtarsal joint (MTJ). When the PT muscle contracts and acts concentrically, it inverts the foot, thereby raising the medial arch. When stretched under tension, acting eccentrically, its function can be seen as a pronation retarder. The integrity of the PT tendon and muscle is crucial to the proper function of the foot, but it is far from the lone actor in maintaining the arch. There is a vital codependence on a host of other muscles and ligaments that when disrupted leads to an almost predictable loss in foot architecture and subsequent pathology.DiagnosisIt is of great importance to have a full evaluation, by a foot and ankle specialist with expertise in addressing complex flatfoot deformities. No two flat feet are alike; therefore, "Universal" treatment plans do not exist for the Adult Flatfoot. It is important to have a custom treatment plan that is tailored to your specific foot. That starts by first understanding all the intricacies of your foot, through an extensive evaluation. X-rays of the foot and ankle are standard, and MRI may be used to better assess the quality of the PT Tendon.Non surgical TreatmentBecause of the progressive nature of PTTD, early treatment is critical. If treated soon enough, symptoms may resolve without the need for surgery and progression of the condition can be stopped. If left untreated, PTTD may create an extremely flat foot, painful arthritis in the foot and ankle, and will limit your ability to walk, run, and other activities. Your podiatrist may recommend one or more of these non-surgical treatments to manage your PTTD. Orthotic devices or bracing. To give your arch the support it needs, your foot and ankle surgeon may recommend an ankle brace or a custom orthotic device that fits into your shoe to support the arch. Immobilization. A short-leg cast or boot may be worn to immobilize the foot and allow the tendon to heal. Physical therapy. Ultrasound therapy and stretching exercises may help rehabilitate the tendon and muscle following immobilization. Medications. Nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen, help reduce the pain and inflammation. Shoe modifications. Your foot and ankle surgeon may recommend changes in your footwear.Surgical TreatmentIn 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.