Posterior Tibial Tendon Dysfunction Causes

Overview
Have you noticed the arch in your foot collapse over a fairly short period of time as an adult? Or Do you suffer from pain on the inside and sole of your arch? If it does, then you may be suffering from a condition known as adult acquired flat foot. As one of the main support structures of the foot?s arch, the tibilais posterior tendon, along with other muscles, tendons and ligaments, play a very important role in its mechanical function.

Causes
The posterior tibial tendon, which connects the bones inside the foot to the calf, is responsible for supporting the foot during movement and holding up the arch. Gradual stretching and tearing of the posterior tibial tendon can cause failure of the ligaments in the arch. Without support, the bones in the feet fall out of normal position, rolling the foot inward. The foot's arch will collapse completely over time, resulting in adult acquired flatfoot. The ligaments and tendons holding up the arch can lose elasticity and strength as a result of aging. Obesity, diabetes, and hypertension can increase the risk of developing this condition. Adult acquired flatfoot is seen more often in women than in men and in those 40 or older.

Symptoms
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.

Diagnosis
Although you can do the "wet test" at home, a thorough examination by a doctor will be needed to identify why the flatfoot developed. Possible causes include a congenital abnormality, a bone fracture or dislocation, a torn or stretched tendon, arthritis or neurologic weakness. For example, an inability to rise up on your toes while standing on the affected foot may indicate damage to the posterior tibial tendon (PTT), which supports the heel and forms the arch. If "too many toes" show on the outside of your foot when the doctor views you from the rear, your shinbone (tibia) may be sliding off the anklebone (talus), another indicator of damage to the PTT. Be sure to wear your regular shoes to the examination. An irregular wear pattern on the bottom of the shoe is another indicator of acquired adult flatfoot. Your physician may request X-rays to see how the bones of your feet are aligned. Muscle and tendon strength are tested by asking you to move the foot while the doctor holds it.

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.

Surgical Treatment
Surgical correction is dependent on the severity of symptoms and the stage of deformity. The goals of surgery are to create a more functional and stable foot. There are multiple procedures available to the surgeon and it may take several to correct a flatfoot deformity. Usually surgical treatment begins with removal of inflammatory tissue and repair of the posterior tibial tendon. A tendon transfer is performed if the posterior tibial muscle is weak or the tendon is badly damaged. The most commonly used tendon is the flexor digitorum longus tendon. This tendon flexes or moves the lesser toes downward. The flexor digitorum longus tendon is utilized due to its close proximity to the posterior tibial tendon and because there are minimal side effects with its loss. The remainder of the tendon is sutured to the flexor hallucis longus tendon that flexes the big toe so that little function is loss.