Posterior tibial tendon insufficiency
(also called posterior tibial tendon dysfunction or adult acquired flatfoot)
has been named literally after failure of the posterior tibial tendon. However, the condition is caused not only by the progressive failure of the posterior tibial tendon; it is also failure of
associated ligaments and joints on the inner side of the ankle and foot. This results in collapse of the arch of the foot, along with the deformity which most often becomes the debilitating problem
in its later stages. While at the beginning the common symptom is pain over the tendon in the inner part of the hindfoot and midfoot, later on it is the deformity that can threaten a person's ability
to walk. Just as the tendon degenerates and loses its function, other soft tissue on the same inner side of the foot - namely the ligaments - degenerate and fail. Ligaments are responsible for
holding bones in place, and when they fail, bones shift to places where they shouldn?t; deformity is the result. The deformity causes malalignment, leading to more stress and failure of the
Adult acquired flatfoot is caused by inflammation and progressive weakening of the major tendon that it is responsible for supporting the arch of the foot. This condition will commonly be accompanied
by swelling and pain on the inner portion of the foot and ankle. Adult acquired flatfoot is more common in women and overweight individuals. It can also be seen after an injury to the foot and ankle.
If left untreated the problem may result in a vicious cycle, as the foot becomes flatter the tendon supporting the arch structure becomes weaker and more and more stretched out. As the tendon becomes
weaker, the foot structure becomes progressively flatter. Early detection and treatment is key, as this condition can lead to chronic swelling and pain.
Some symptoms of adult acquired flat foot are pain along the inside of the foot and ankle, pain that increases with activity, and difficulty walking for long periods of time. You may experience
difficulty standing, pain on the outside of the ankle, and bony bumps on the top of the foot and inside the foot. You may also have numbness and tingling of the feet and toes (may result from large
bone spurs putting pressure on nerves), swelling, a large bump on the sole of the foot and/or an ulcer (in diabetic patients). Diabetic patients should wear a properly fitting diabetic shoe wear to
prevent these complications from happening.
The diagnosis of tibialis posterior dysfunction is essentially clinical. However, plain radiographs of the foot and ankle are useful for assessing the degree of deformity and to confirm the presence
or absence of degenerative changes in the subtalar and ankle articulations. The radiographs are also useful to exclude other causes of an acquired flatfoot deformity. The most useful radiographs are
bilateral anteroposterior and lateral radiographs of the foot and a mortise (true anteroposterior) view of the ankle. All radiographs should be done with the patient standing. In most cases we see no
role for magnetic resonance imaging or ultrasonography, as the diagnosis can be made clinically.
Non surgical Treatment
The adult acquired flatfoot is best treated early. There is no recommended home treatment other than the general avoidance of prolonged weightbearing in non-supportive footwear until the patient can
be seen in the office of the foot and ankle specialist. In Stage I, the inflammation and tendon injury will respond to rest, protected ambulation in a cast, as well as anti-inflammatory therapy.
Follow-up treatment with custom-molded foot orthoses and properly designed athletic or orthopedic footwear are critical to maintain stability of the foot and ankle after initial symptoms have been
calmed. Once the tendon has been stretched, the foot will become deformed and visibly rolled into a pronated position at the ankle. Non-surgical treatment has a significantly lower chance of success.
Total immobilization in a cast or Camwalker may calm down symptoms and arrest progression of the deformity in a smaller percentage of patients. Usually, long-term use of a brace known as an ankle
foot orthosis is required to stop progression of the deformity without surgery. A new ankle foot orthosis known as the Richie Brace, offered by PAL Health Systems, has proven to show significant
success in treating Stage II posterior tibial dysfunction and the adult acquired flatfoot. This is a sport-style brace connected to a custom corrected foot orthotic device that fits well into most
forms of lace-up footwear, including athletic shoes. The brace is light weight and far more cosmetically appealing than the traditional ankle foot orthosis previously prescribed.
If conservative treatment fails surgical intervention is offered. For a Stage 1 deformity a posterior tibial tendon tenosynovectomy (debridement of the tendon) or primary repair may be indicated. For
Stage 2 a combination of Achilles lengthening with bone cuts, calcaneal osteotomies, and tendon transfers is common. Stage 2 flexible PTTD is the most common stage patients present with for
treatment. In Stage 3 or 4 PTTD isolated fusions, locking two or more joints together, maybe indicated. All treatment is dependent on the stage and severity at presentation with the goals and
activity levels of the patient in mind. Treatment is customized to the individual patient needs.