Acquired Flat Foot Tibialis Posterior Tenosynovitis

Overview
The posterior tibial tendon serves as one of the major supporting structures of the foot, helping it to function while walking. Posterior tibial tendon dysfunction (PTTD) is a condition caused by changes in the tendon, impairing its ability to support the arch. This results in flattening of the foot. PTTD is often called ?adult acquired flatfoot? because it is the most common type of flatfoot developed during adulthood. Although this condition typically occurs in only one foot, some people may develop it in both feet. PTTD is usually progressive, which means it will keep getting worse, especially if it isn?t treated early.

Causes
As discussed above, many different problems can create a painful flatfoot. Damage to the posterior tibial tendon is the most common cause of AAFD. The posterior tibial tendon is one of the most important tendons of the leg. It starts at a muscle in the calf, travels down the inside of the lower leg and attaches to the bones on the inside of the foot. The main function of this tendon is to support the arch of your foot when you walk. If the tendon becomes inflamed or torn, the arch will slowly collapse. Women and people over 40 are more likely to develop problems with the posterior tibial tendon. Other risk factors include obesity, diabetes, and hypertension. Having flat feet since childhood increases the risk of developing a tear in the posterior tibial tendon. In addition, people who are involved in high impact sports, such as basketball, tennis, or soccer, may have tears of the tendon from repetitive use. Inflammatory arthritis, such as rheumatoid arthritis, can cause a painful flatfoot. This type of arthritis attacks not only the cartilage in the joints, but also the ligaments that support the foot. Inflammatory arthritis not only causes pain, but also causes the foot to change shape and become flat. The arthritis can affect the back of the foot or the middle of foot, both of which can result in a fallen arch. An injury to the tendons or ligaments in the foot can cause the joints to fall out of alignment. The ligaments support the bones and prevent them from moving. If the ligaments are torn, the foot will become flat and painful. This more commonly occurs in the middle of the foot (Lisfranc injury), but can also occur in the back of the foot. Injuries to tendons of the foot can occur either in one instance (traumatically) or with repeated use over time (overuse injury). Regardless of the cause, if tendon function is altered, the forces that are transmitted across joints in the foot are changed and this can lead to increased stress on joint cartilage and ligaments. In addition to tendon and ligament injuries, fractures and dislocations of the bones in the midfoot can also lead to a flatfoot deformity. People with diabetes or with nerve problems that limits normal feeling in the feet, can have collapse of the arch or of the entire foot. This type of arch collapse is typically more severe than that seen in patients with normal feeling in their feet. In addition to the ligaments not holding the bones in place, the bones themselves can sometimes fracture and disintegrate without the patient feeling any pain. This may result in a severely deformed foot that is very challenging to correct with surgery. Special shoes or braces are the best method for dealing with this problem.

Symptoms
Many patients with this condition have no pain or symptoms. When problems do arise, the good news is that acquired flatfoot treatment is often very effective. Initially, it will be important to rest and avoid activities that worsen the pain.

Diagnosis
In the early stages of dysfunction of the posterior tibial tendon, most of the discomfort is located medially along the course of the tendon and the patient reports fatigue and aching on the plantar-medial aspect of the foot and ankle. Swelling is common if the dysfunction is associated with tenosynovitis. As dysfunction of the tendon progresses, maximum pain occurs laterally in the sinus tarsi because of impingement of the fibula against the calcaneus. With increasing deformity, patients report that the shape of the foot changes and that it becomes increasingly difficult to wear shoes. Many patients no longer report pain in the medial part of the foot and ankle after a complete rupture of the posterior tibial tendon has occurred; instead, the pain is located laterally. If a fixed deformity has not occurred, the patient may report that standing or walking with the hindfoot slightly inverted alleviates the lateral impingement and relieves the pain in the lateral part of the foot.

Non surgical Treatment
Non-surgical treatment includes rest and reducing your activity until the pain improves. Orthotics or bracing help support the tendon to reduce its pull along the arch, thus reducing pain. In moderate to severe cases, a below knee cast or walking boot may be needed to allow the tendon to rest completely and heal. Physical therapy is an integral part of the non-surgical treatment regimen to reduce inflammation and pain. Anti-inflammatory medication is often used as well. Many times evaluation of your current shoes is necessary to ensure you are wearing appropriate shoe gear to prevent re-injury.

Surgical Treatment
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.