This condition is characterized by a progressive flattening or falling of the arch. It is often referred to as posterior tibial tendon dysfunction (PTTD) and is becoming a more commonly recognized
foot problem. Since the condition develops over time, it is typically diagnosed in adulthood. It usually only develops in one foot although it can affect both. Since it is progressive, it is common
for symptoms to worsen, especially when it is not treated early. The posterior tibial tendon attaches to the bones on the inside of your foot and is vital to the support structure within the foot.
With PTTD, changes in the tendon impair its ability to function normally. The result is less support for the arch, which in turn causes it to fall or flatten. A flattening arch can cause the heel to
shift out of alignment, the forefoot to rotate outward, the heel cord to tighten, and possible deformity of the foot. Common symptoms include pain along the inside of the ankle, swelling, an inward
rolling of the ankle, pain that is worse with activity, and joint pain
Causes of an adult acquired flatfoot may include Neuropathic foot (Charcot foot) secondary to Diabetes mellitus, Leprosy, Profound peripheral neuritis of any cause. Degenerative changes in the ankle,
talonavicular or tarsometatarsal joints, or both, secondary to Inflammatory arthropathy, Osteoarthropathy, Fractures, Acquired flatfoot resulting from loss of the supporting structures of the medial
longitudinal arch. Dysfunction of the tibialis posterior tendon Tear of the spring (calcaneoanvicular) ligament (rare). Tibialis anterior rupture (rare). Painful flatfoot can have other causes, such
as tarsal coalition, but as such a patient will not present with a change in the shape of the foot these are not included here.
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.
The adult acquired flatfoot, secondary to posterior tibial tendon dysfunction, is diagnosed in a number of ways with no single test proven to be totally reliable. The most accurate diagnosis is made
by a skilled clinician utilizing observation and hands on evaluation of the foot and ankle. Observation of the foot in a walking examination is most reliable. The affected foot appears more pronated
and deformed compared to the unaffected foot. Muscle testing will show a strength deficit. An easy test to perform in the office is the single foot raise. A patient is asked to step with full body
weight on the symptomatic foot, keeping the unaffected foot off the ground. The patient is then instructed to "raise up on the tip toes" of the affected foot. If the posterior tibial tendon has been
attenuated or ruptured, the patient will be unable to lift the heel off the floor and rise onto the toes. In less severe cases, the patient will be able to rise on the toes, but the heel will not be
noted to invert as it normally does when we rise onto the toes. X-rays can be helpful but are not diagnostic of the adult acquired flatfoot. Both feet - the symptomatic and asymptomatic - will
demonstrate a flatfoot deformity on x-ray. Careful observation may show a greater severity of deformity on the affected side.
Non surgical Treatment
Orthotic or anklebrace, Over-the-counter or custom shoe inserts to position the foot and relieve pain are the most common non-surgical treatment option. Custom orthotics are often suggested if the
shape change of the foot is more severe. An ankle brace (either over-the-counter or custom made) is another option that will help to ease tendon tension and pain. Boot immobilization. A walking boot
supports the tendon and allows it to heal. Activity modifications. Depending on what we find, we may recommend limiting high-impact activities, such as running, jumping or court sports, or switching
out high-impact activities for low-impact options for a period of time. Ice and anti-inflammatory medications. These may be given as needed to decrease your symptoms.
When conservative care fails to control symptoms and/or deformity, then surgery may be needed. The goal of surgical treatment is to obtain good alignment while keeping the foot and ankle as flexible
as possible. The most common procedures used with this condition include arthrodesis (fusion), osteotomy (cutting out a wedge-shaped piece of bone), and lateral column lengthening. Lateral column
lengthening involves the use of a bone graft at the calcaneocuboid joint. This procedure helps restore the medial longitudinal arch (arch along the inside of the foot). A torn tendon or spring
ligament will be repaired or reconstructed. Other surgical options include tendon shortening or lengthening. Or the surgeon may move one or more tendons. This procedure is called a tendon transfer.
Tendon transfer uses another tendon to help the posterior tibial tendon function more effectively. A tendon transfer is designed to change the force and angle of pull on the bones of the arch. It's
not clear yet from research evidence which surgical procedure works best for this condition. A combination of surgical treatments may be needed. It may depend on your age, type and severity of
deformity and symptoms, and your desired level of daily activity.