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.
There are multiple factors contributing to the development of this problem. Damage to the nerves, ligaments, and/or tendons of the foot can cause subluxation (partial dislocation) of the subtalar or talonavicular joints. Bone fracture is a possible cause. The resulting joint deformity from any of these problems can lead to adult-acquired flatfoot deformity. Dysfunction of the posterior tibial tendon has always been linked with adult-acquired flatfoot deformity (AAFD). The loss of active and passive pull of the tendon alters the normal biomechanics of the foot and ankle. The reasons for this can be many and varied as well. Diabetes, high blood pressure, and prolonged use of steroids are some of the more common causes of adult-acquired flatfoot deformity (AAFD) brought on by impairment of the posterior tibialis tendon. Overstretching or rupture of the tendon results in tendon and muscle imbalance in the foot leading to adult-acquired flatfoot deformity (AAFD). Rheumatoid arthritis is one of the more common causes. About half of all adults with this type of arthritis will develop adult flatfoot deformity over time. In such cases, the condition is gradual and progressive. Obesity has been linked with this condition. Loss of blood supply for any reason in the area of the posterior tibialis tendon is another factor. Other possible causes include bone fracture or dislocation, a torn or stretched tendon, or a neurologic condition causing weakness.
Symptoms shift around a bit, depending on what stage of PTTD you?re in. For instance, you?re likely to start off with tendonitis, or inflammation of the posterior tibial tendon. This will make the area around the inside of your ankle and possibly into your arch swollen, reddened, warm to the touch, and painful. Inflammation may actually last throughout the stages of PTTD. The ankle will also begin to roll towards the inside of the foot (pronate), your heel may tilt, and you may experience some pain in your leg (e.g. shin splints). As the condition progresses, the toes and foot begin to turn outward, so that when you look at your foot from the back (or have a friend look for you, because-hey-that can be kind of a difficult
maneuver to pull off) more toes than usual will be visible on the outside (i.e. the side with the pinky toe). At this stage, the foot?s still going to be flexible, although it will likely have flattened somewhat due to the lack of support from the posterior tibial tendon. You may also find it difficult to stand on your toes. Finally, you may reach a stage in which your feet are inflexibly flat. At this point, you may experience pain below your ankle on the outside of your foot, and you might even develop arthritis in the ankle.
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
Nonoperative therapy for adult-acquired flatfoot is a reasonable treatment option that is likely to be beneficial for most patients. In this article, we describe the results of a retrospective cohort study that focused on nonoperative measures, including bracing, physical therapy, and anti-inflammatory medications, used to treat adult-acquired flatfoot in 64 consecutive patients. The results revealed the incidence of successful nonsurgical treatment to be 87.5% (56 of 64 patients), over the 27-month observation period. Overall, 78.12% of the patients with adult-acquired flatfoot were obese (body mass index [BMI] = 30), and 62.5% of the patients who failed nonsurgical therapy were obese; however, logistic regression failed to show that BMI was statistically significantly associated with the outcome of treatment. The use of any form of bracing was statistically significantly associated with successful nonsurgical treatment (fully adjusted OR = 19.8621, 95% CI 1.8774 to 210.134), whereas the presence of a split-tear of the tibialis posterior on magnetic resonance image scans was statistically significantly associated with failed nonsurgical treatment (fully adjusted OR = 0.016, 95% CI 0.0011 to 0.2347). The results of this investigation indicate that a systematic nonsurgical treatment approach to the treatment of the adult-acquired flatfoot deformity can be successful in most cases.
Good to excellent results for more than 80% of patients have been reported at five years’ follow up for the surgical interventions recommended below. However, the postoperative recovery is a lengthy process, and most surgical procedures require patients to wear a plaster cast for two to three months. Although many patients report that their function is well improved by six months, in our experience a year is required to recover truly and gain full functional improvement after the surgery. Clearly, some patients are not candidates for such major reconstructive surgery.