Adult-acquired flatfoot or collapsed arch occurs because the large tendon on the inside of the ankle - the posterior tibial tendon - becomes stretched out and no longer supports the foot?s arch. In many cases, the condition worsens and and the tendon thickens, becoming painful, especially during activities. Flatfoot or collapsed arch is also known as posterior tibial tendon dysfunction. This condition is different than having flat feet since birth (known as congenital flatfoot), although sometimes these patients develop similar symptoms and require similar treatments.
Rheumatoid arthritis This type of arthritis attacks the cartilage in the foot, leading to pain and flat feet. It is caused by auto-immune disease, where the body?s immune system attacks its own tissues. Diabetes. Having diabetes can cause nerve damage and affect the feeling in your feet and cause arch collapse. Bones can also fracture but some patients may not feel any pain due to the nerve damage. Obesity and/or hypertension (high blood pressure) This increases your risk of tendon damage and resulting flat foot.
Pain along the inside of the foot and ankle, where the tendon lies. This may or may not be associated with swelling in the area. Pain that is worse with activity. High-intensity or high-impact activities, such as running, can be very difficult. Some patients can have trouble walking or standing for a long time. Pain on the outside of the ankle. When the foot collapses, the heel bone may shift to a new position outwards. This can put pressure on the outside ankle bone. The same type of pain is found in arthritis in the back of the foot. Asymmetrical collapsing of the medial arch on the affected side.
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
The adult acquired flatfoot is best treated early. Accurate assessment by your doctor will determine which treatment is suitable for you. Reduce your level of activity and follow the RICE regime. R - rest as often as you are able. Refrain from activity that will worsen your condition, such as sports and walking. I - ice, apply to the affected area, ensure you protect the area from frostbite by applying a towel over the foot before using the ice pack. C - compression, a Tubigrip or elasticated support bandage may be applied to relieve symptoms and ease pain and discomfort. E - elevate the affected foot to reduce painful swelling. You will be prescribed pain relief in the form of non-steroidal antiinflammatory medications (if you do not suffer with allergies or are asthmatic). Immobilisation of your affected foot - this will involve you having a below the knee cast for four to eight weeks. In certain circumstances it is possible for you to have a removable boot instead of a cast. A member of the foot and ankle team will advise as to whether this option is suitable for you. Footwear is important - it is advisable to wear flat sturdy lace-up shoes, for example, trainers or boots. This will not only support your foot, but will also accommodate orthoses (shoe inserts).
Surgery should only be done if the pain does not get better after a few months of conservative treatment. The type of surgery depends on the stage of the PTTD disease. It it also dictated by where tendonitis is located and how much the tendon is damaged. Surgical reconstruction can be extremely complex. Some of the common surgeries include. Tenosynovectomy, removing the inflamed tendon sheath around the PTT. Tendon Transfer, to augment the function of the diseased posterior tibial tendon with a neighbouring tendon. Calcaneo-osteotomy, sometimes the heel bone needs to be corrected to get a better heel bone alignment. Fusion of the Joints, if osteoarthritis of the foot has set in, fusion of the joints may be necessary.