A painful flat foot, or adult acquired flatfoot deformity, is a progressive collapsing of the arch of the foot that occurs as the posterior tibial tendon becomes insufficient due to various factors. Early stages may present with only pain along the posterior tibial tendon whereas advanced deformity usually results in arthritis and rigidity of the rearfoot and ankle.
A person with flat feet has greater load placed on the posterior tibial tendon which is the main tendon unit supporting up the arch of the foot. Throughout life, aging leads to decreased strength of muscles, tendons and ligaments. The blood supply diminishes to tendons with aging as arteries narrow. Heavier, obese patients have more weight on the arch and have greater narrowing of arteries due to atherosclerosis. In some people, the posterior tibial tendon finally gives out or tears. This is not a sudden event in most cases. Rather, it is a slow, gradual stretching followed by inflammation and degeneration of the tendon. Once the posterior tibial tendon stretches, the ligaments of the arch stretch and tear. The bones of the arch then move out of position with body weight pressing down from above. The foot rotates inward at the ankle in a movement called pronation. The arch appears collapsed, and the heel bone is tilted to the inside. The deformity can progress until the foot literally dislocates outward from under the ankle joint.
Symptoms shift around a bit, depending on what stage of PTTD you?re in. For instance, you?re likely to start off with tendonitis, or inflammation of the posterior tibial tendon. This will make the area around the inside of your ankle and possibly into your arch swollen, reddened, warm to the touch, and painful. Inflammation may actually last throughout the stages of PTTD. The ankle will also begin to roll towards the inside of the foot (pronate), your heel may tilt, and you may experience some pain in your leg (e.g. shin splints). As the condition progresses, the toes and foot begin to turn outward, so that when you look at your foot from the back (or have a friend look for you, because-hey-that can be kind of a difficult
maneuver to pull off) more toes than usual will be visible on the outside (i.e. the side with the pinky toe). At this stage, the foot?s still going to be flexible, although it will likely have flattened somewhat due to the lack of support from the posterior tibial tendon. You may also find it difficult to stand on your toes. Finally, you may reach a stage in which your feet are inflexibly flat. At this point, you may experience pain below your ankle on the outside of your foot, and you might even develop arthritis in the ankle.
Examination by your foot and ankle specialist can confirm the diagnosis for most patients. An ultrasound exam performed in the office setting can evaluate the status of the posterior tibial tendon, the tendon which is primarily responsible for supporting the arch structure of the foot.
Non surgical Treatment
Initial treatment for most patients consists of rest and anti-inflammatory medications. This will help reduce the swelling and pain associated with the condition. The long term treatment for the problem usually involves custom made orthotics and supportive shoe gear to prevent further breakdown of the foot. ESWT(extracorporeal shock wave therapy) is a novel treatment which uses sound wave technology to stimulate blood flow to the tendon to accelerate the healing process. This can help lead to a more rapid return to normal activities for most patients. If treatment is initiated early in the process, most patients can experience a return to normal activities without the need for surgery.
If surgery is necessary, a number of different procedures may be considered. The specifics of the planned surgery depend upon the stage of the disorder and the patient?s specific goals. Procedures may include ligament and muscle lengthening, removal of the inflamed tendon lining, tendon transfers, cutting and realigning bones, placement of implants to realign the foot and joint fusions. In general, early stage disease may be treated with tendon and ligament (soft-tissue) procedures with the addition of osteotomies to realign the foot. Later stage disease with either a rigidly fixed deformity or with arthritis is often treated with fusion procedures. If you are considering surgery, your doctor will speak with about the specifics of the planned procedure.