Adult-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.
Posterior tibial tendon dysfunction is the most common cause of acquired adult flatfoot. Sometimes this can be a result of specific trauma, but usually the tendon becomes injured from wear and tear
over time. This is more prevalent in individuals with an inherited flat foot but excessive weight, age, and level of activity are also contributing factors.
Posterior tibial tendon insufficiency is divided into stages by most foot and ankle specialists. In stage I, there is pain along the posterior tibial tendon without deformity or collapse of the arch.
The patient has the somewhat flat or normal-appearing foot they have always had. In stage II, deformity from the condition has started to occur, resulting in some collapse of the arch, which may or
may not be noticeable. The patient may feel it as a weakness in the arch. Many patients initially present in stage II, as the ligament failure can occur at the same time as the tendon failure and
therefore deformity can already be occurring as the tendon is becoming symptomatic. In stage III, the deformity has progressed to the extent where the foot becomes fixed (rigid) in its deformed
position. Finally, in stage IV, deformity occurs at the ankle in addition to the deformity in the foot.
Diagnostic testing is often used to diagnose the condition and help determine the stage of the disease. The most common test done in the office setting are weightbearing X-rays of the foot and ankle.
These assess joint alignment and osteoarthritis. If tendon tearing or rupture is suspected, the gold standard test would be MRI. The MRI is used to check the tendon, surrounding ligament structures
and the midfoot and hindfoot joints. An MRI is essential if surgery is being considered.
Non surgical Treatment
Stage one deformities usually respond to conservative or non-surgical therapy such as anti-inflammatory medication, casting, functional orthotics or a foot ankle orthosis called a Richie Brace. If
these modalities are unsuccessful surgery is warranted.
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. Your foot
and ankle surgeon will determine the best approach for you.