Flatfoot may sound like a characteristic of a certain water animal rather than a human problem. Flatfoot is a condition in which the arch of the foot is fallen and the foot is pointed outward. In contrast to a flatfoot condition that has always been present, this type develops after the skeleton has reached maturity. There are several situations that can result in fallen arches, including fracture, dislocation, tendon laceration, tarsal coalition, and arthritis. One of the most common conditions that can lead to this foot problem is posterior tibial tendon dysfunction. The posterior tibial tendon attaches the calf muscle to the bones on the inside of the foot and is crucial in holding up and supporting the arch. An acute injury or overuse can cause this tendon to become inflamed or even torn, and the arch of the foot will slowly fall over time.
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.
Initially, flatfoot deformity may not present with any symptoms. However, overtime as the tendon continues to function in an abnormal position, people with fallen arches will begin to have throbbing or sharp pain along the inside of the arch. Once the tendon and soft tissue around it elongates, there is no strengthening exercises or mechanism to shorten the tendon back to a normal position. Flatfoot can also occur in one or both feet. If the arch starts to slowly collapse in one foot and not the other, posterior tibial dysfunction (PTTD) is the most likely cause. People with flatfoot may only have pain with certain activities such as running or exercise in the early phase of PTTD. Pain may start from the arch and continue towards the inside part of the foot and ankle where the tendon courses from the leg. Redness, swelling and increased warmth may also occur. Later signs of PTTD include pain on the outside of the foot from the arch collapsing and impinging other joints. Arthritic symptoms such as painful, swollen joints in the foot and ankle may occur later as well due to the increased stress on the joints from working in an abnormal position for a long period of time.
Posterior Tibial Tendon Dysfunction is diagnosed with careful clinical observation of the patient?s gait (walking), range of motion testing for the foot and ankle joints, and diagnostic imaging. People with flatfoot deformity walk with the heel angled outward, also called over-pronation. Although it is normal for the arch to impact the ground for shock absorption, people with PTTD have an arch that fully collapses to the ground and does not reform an arch during the entire gait period. After evaluating the ambulation pattern, the foot and ankle range of motion should be tested. Usually the affected foot will have decreased motion to the ankle joint and the hindfoot. Muscle strength may also be weaker as well. An easy test to perform for PTTD is the single heel raise where the patient is asked to raise up on the ball of his or her effected foot. A normal foot type can lift up on the toes without pain and the heel will invert slightly once the person has fully raised the heel up during the test. In early phases of PTTD the patient may be able to lift up the heel but the heel will not invert. An elongated or torn posterior tibial tendon, which is a mid to late finding of PTTD, will prohibit the patient from fully rising up on the heel and will cause intense pain to the arch. Finally diagnostic imaging, although used alone cannot diagnose PTTD, can provide additional information for an accurate diagnosis of flatfoot deformity. Xrays of the foot can show the practitioner important angular relationships of the hindfoot and forefoot which help diagnose flatfoot deformity. Most of the time, an MRI is not needed to diagnose PTTD but is a tool that should be considered in advanced cases of flatfoot deformity. If a partial tear of the posterior tibial tendon is of concern, then an MRI can show the anatomic location of the tear and the extensiveness of the injury.
Non surgical Treatment
Conservative (nonoperative) care is advised at first. A simple modification to your shoe may be all that???s needed. Sometimes purchasing shoes with a good arch support is sufficient. For other patients, an off-the-shelf (prefabricated) shoe insert works well. The orthotic is designed specifically to position your foot in good alignment. Like the shoe insert, the orthotic fits inside the shoe. These work well for mild deformity or symptoms. Over-the-counter pain relievers or antiinflammatory drugs such as ibuprofen may be helpful. If symptoms are very severe, a removable boot or cast may be used to rest, support, and stabilize the foot and ankle while still allowing function. Patients with longer duration of symptoms or greater deformity may need a customized brace. The brace provides support and limits ankle motion. After several months, the brace is replaced with a foot orthotic. A physical therapy program of exercise to stretch and strengthen the foot and leg muscles is important. The therapist will also show you how to improve motor control and proprioception (joint sense of position). These added features help prevent and reduce injuries.
If cast immobilization fails, surgery is the next alternative. Treatment goals include eliminating pain, halting deformity progression and improving mobility. Subtalar Arthroereisis, 15 minute outpatient procedure, may correct flexible flatfoot deformity (hyperpronation). The procedure involves placing an implant under the ankle joint (sinus tarsi) to prevent abnormal motion. Very little recovery time is required and it is completely reversible if necessary. Ask your Dallas foot doctor for more information about this exciting treatment possibility.