The disease, which lasts over a long period of time, can cause damage to cartilage, bone, tendons and ligaments (DynoMed.com, 2000).
Foot deformities are very common in RA. These deformities may affect patient functional foot, especially hallux rigidus and calcaneal valgus (Bal, et al. 2006). Human foot is more susceptible to arthritis because the human foot contains 33 joints. About 90 percent of RA patients will complain of problems with the midfoot and forefoot while 67 percent will have problems with the hindfoot and ankle. The ankle is usually the last joint to be involved with RA (DynoMed.com, 2000).
RA causes inflammation in the lining (synovium) of joints, most often the joints of the feet. The most common symptoms of RA in the foot are pain, swelling, and stiffness. Symptoms usually appear in several joints on both feet. The signs of inflammation can also include a feeling of warmth around affected joints. In some patients, chronic inflammation results in damage to the cartilage and bones in the joint. Serious damage can lead to permanent joint destruction, deformity, and disability (FootPhysicans.com, 2007). With the progress in the disease the feeling of pain in the joint or in the sole or ball of the foot will increase. The joint may be warm and the way the patient walk may be affected. In addition the patient may develop corns or bunions, and the toes can begin to curl and stiffen in positions called claw toe or hammer toe. Corns, or even ulcers, may develop on the foot.
Metatarsalgia, a general term for pain in the sole or the ball of the foot, is also very common. This indicates that RA is affecting the metatarsal joints of the toes. Hindfoot and ankle pain often involves the posterior tibial tendon. The ankle itself is usually the last joint in the foot to be involved with RA (DynoMed.com, 2000).
As the disease progresses in the foot region, the joint space becomes narrow and bone begins to rub on bone, leading to painful arthritis. Besides, deformities may occur resulting in loosening of the ligaments and capsule lining of the joint. If the housing of the joint or the capsule loosens up considerably, the joints mostly in front of the foot may dislocate. This can cause painful swelling on the bottom of the ball of the foot that can make walking even more terribly uncomfortable. Later the big toe begins to deviate and bunions may form on the inside of the big toe (footandankle.mdmercy.com, N.D.).
In cases where the hindfoot (back of the foot) and ankle are affected, the bones may shift position in the joints. This can cause the long arch on the bottom of your foot to collapse (flatfoot), resulting in severe pain and difficulty walking. Because RA affects the entire system, the patient may also feel feverish, tire easily, and lose appetite (AAOS, 2001).
The exact cause for RA is still unknown, but there are many thoughts about what might contribute to it. A sudden and traumatic injury such as a broken bone, torn ligament, or ankle sprain can cause the injured joint to become arthritic in the future. According to Cotran et al, (1994)"...RA is triggered by exposure of an immuno-genetically susceptible host to an arthritogenic microbial antigen". Heredity, or the genes from the parents, may be a determining factor in who gets rheumatoid arthritis. Roth explains that this "genetic predisposition appears to be related to the