Originally known as posterior tibial tendon dysfunction or insufficiency, adult-acquired flatfoot deformity encompasses a wide range of deformities. These deformities vary in location, severity, and rate of progression. Establishing a diagnosis as early as possible is one of the most important factors in treatment. Prompt early, aggressive nonsurgical management is important. A patient in whom such treatment fails should strongly consider surgical correction to avoid worsening of the deformity. In all four stages of deformity, the goal of surgery is to achieve proper alignment and maintain as much flexibility as possible in the foot and ankle complex. However, controversy remains as to how to manage flexible deformities, especially those that are severe.
Women are affected by Adult Acquired Flatfoot four times more frequently than men. Adult Flatfoot generally occurs in middle to older age people. Most people who acquire the condition already have flat feet. One arch begins to flatten more, then pain and swelling develop on the inside of the ankle. This condition generally affects only one foot. It is unclear why women are affected more often than men. But factors that may increase your risk of Adult Flatfoot include diabetes, hypertension, and obesity.
As different types of flatfoot have different causes, the associated symptoms can be different for different people. Some generalized symptoms are listed. Pain along the course of the posterior tibial tendon which lies on the inside of the foot and ankle. This can be associated with swelling on the inside of the ankle. Pain that is worse with activity. High intensity or impact activities, such as running and jumping, can be very difficult. Some patients can have difficulty walking or even standing for long periods of time and may experience pain at the inside of the ankle and in the arch of the foot. Feeling like one is ?dragging their foot.? When the foot collapses, the heel bone may shift position and put pressure on the outside ankle bone (fibula). This can cause pain in the bones and tendons in the outside of the ankle joint. Patients with an old injury or arthritis in the middle of the foot can have painful, bony bumps on the top and inside of the foot. These make shoe wear very difficult. Sometimes, the bony spurs are so large that they pinch the nerves which can result in numbness and tingling on the top of the foot and into the toes. Diabetic patients may not experience pain if they have damage to their nerves. They may only notice swelling or a large bump on the bottom of the foot. The large bump can cause skin problems and an ulcer (a sore that does not heal) may develop if proper diabetic shoe wear is not used.
Starting from the knee down, check for any bowing of the tibia. A tibial varum will cause increased medial stress on the foot and ankle. This is essential to consider in surgical planning. Check the gastrocnemius muscle and Achilles complex via a straight and bent knee check for equinus. If the range of motion improves to at least neutral with bent knee testing of the Achilles complex, one may consider a gastrocnemius recession. If the Achilles complex is still tight with bent knee testing, an Achilles lengthening may be necessary. Check the posterior tibial muscle along its entire course. Palpate the muscle and observe the tendon for strength with a plantarflexion and inversion stress test. Check the flexor muscles for strength in order to see if an adequate transfer tendon is available. Check the anterior tibial tendon for size and strength.
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.
Stage two deformities are less responsive to conservative therapies that can be effective in mild deformities. Bone procedures are necessary at this stage in order to recreate the arch and stabilize the foot. These procedures include isolated fusion procedures, bone grafts, and/or the repositioning of bones through cuts called osteotomies. The realigned bones are generally held in place with screws, pins, plates, or staples while the bone heals. A tendon transfer may or may not be utilized depending on the condition of the posterior tibial tendon. Stage three deformities are better treated with surgical correction, in healthy patients. Patients that are unable to tolerate surgery or the prolonged healing period are better served with either arch supports known as orthotics or bracing such as the Richie Brace. Surgical correction at this stage usually requires fusion procedures such as a triple or double arthrodesis. This involves fusing the two or three major bones in the back of the foot together with screws or pins. The most common joints fused together are the subtalar joint, talonavicular joint, and the calcaneocuboid joint. By fusing the bones together the surgeon is able to correct structural deformity and alleviate arthritic pain. Tendon transfer procedures are usually not beneficial at this stage. Stage four deformities are treated similarly but with the addition of fusing the ankle joint.