Adult-acquired flatfoot is a challenging condition to treat. It is defined as a symptomatic, progressive deformity of the foot caused by loss of supportive structures of the medial arch. It is becoming increasingly frequent with the aging population and the obesity epidemic. Patients commonly try to lose weight by exercising to improve the condition. This often leads to worsening of symptoms and progression of the disorder. Early recognition of this complex disorder is essential, if chronic pain and surgery are to be avoided.
Flat feet causes greater pressure on the posterior tibial tendon than normal. As the person with flat feet ages, the muscles, tendons and ligaments weaken. Blood supplies diminish as arteries narrow. These conditions are magnified for obese patients because of their increased weight and atherosclerosis. Finally, the tendon gives out or tears. Most of the time, this is a slow process. Once the posterior tibial tendon and ligaments stretch, body weight causes the bones of the arch to move out of position. The foot rotates inward (pronation), the heel bone is tilted to the inside, and the arch appears collapsed. In some cases, the deformity progresses until the foot dislocates outward from the ankle joint.
The symptoms of PTTD may include pain, swelling, a flattening of the arch, and inward rolling of the ankle. As the condition progresses, the symptoms will change. For example, later, as the arch begins to flatten, there may still be pain on the inside of the foot and ankle. But at this point, the foot and toes begin to turn outward and the ankle rolls inward. As PTTD becomes more advanced, the arch flattens even more and the pain often shifts to the outside of the foot, below the ankle. The tendon has deteriorated considerably and arthritis often develops in the foot. In more severe cases, arthritis may also develop in the ankle. Symptoms, which may occur in some persons with flexible flatfoot, include. Pain in the heel, arch, ankle, or along the outside of the foot. ?Turned-in? ankle. Pain associated with a shin splint. General weakness / fatigue in the foot or leg.
Observe forefoot to hindfoot alignment. Do this with the patient sitting and the heel in neutral, and also with the patient standing. I like to put blocks under the forefoot with the heel in neutral to see how much forefoot correction is necessary to help hold the hindfoot position. One last note is to check all joints for stiffness. In cases of prolonged PTTD or coalition, rigid deformity is present and one must carefully check the joints of the midfoot and hindfoot for stiffness and arthritis in the surgical pre-planning.
Non surgical Treatment
PTTD is a progressive condition. Early treatment is needed to prevent relentless progression to a more advanced disease which can lead to more problems for that affected foot. In general, the treatments include rest. Reducing or even stopping activities that worsen the pain is the initial step. Switching to low-impact exercise such as cycling, elliptical trainers, or swimming is helpful. These activities do not put a large impact load on the foot. Ice. Apply cold packs on the most painful area of the posterior tibial tendon frequently to keep down the swelling. Placing ice over the tendon immediately after completing an exercise helps to decrease the inflammation around the tendon. Nonsteroidal Anti-inflammatory Medication (NSAIDS). Drugs, such as arcoxia, voltaren and celebrex help to reduce pain and inflammation. Taking such medications prior to an exercise activity helps to limit inflammation around the tendon. However, long term use of these drugs can be harmful to you with side effects including peptic ulcer disease and renal impairment or failure. Casting. A short leg cast or walking boot may be used for 6 to 8 weeks in the acutely painful foot. This allows the tendon to rest and the swelling to go down. However, a cast causes the other muscles of the leg to atrophy (decrease in strength) and thus is only used if no other conservative treatment works. Most people can be helped with orthotics and braces. An orthotic is a shoe insert. It is the most common non-surgical treatment for a flatfoot and it is very safe to use. A custom orthotic is required in patients who have moderate to severe changes in the shape of the foot. Physiotherapy helps to strengthen the injured tendon and it can help patients with mild to moderate disease of the posterior tibial tendon.
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.