Rheumatoid arthritis is a chronic, systemic, inflammatory, autoimmune disease for which there is no known cure. It affects approximately 2.1 million Americans.
Patients with rheumatoid arthritis (RA) often present with pain in the metatarsal heads (balls of the feet). In fact, this is one of the more common modes of onset.
If uncontrolled, rheumatoid arthritis can lead to multiple deformities including hammer toes (where the toes bend at the knuckle and calluses develop at the tips of the toe), hallux valgus (bunions), and subluxation of the metatarsal heads (where the joints in the balls of the feet become so deformed that the balls of the feet and the toes become disconnected."
In addition, patients with rheumatoid arthritis are prone to develop flat feet and a condition known as hindfoot valgus, where the back of the foot and ankle tilt outwards. This places a lot of stress on the tendons along the inside part of the ankle. Eventually the ankle can collapse.
Rheumatoid arthritis can also lead to damage of the small nerves in the feet so that patients no longer have the proper ability to sense the ground as they walk. This makes them more prone to fall.
Recently, a new study showed that patients with rheumatoid arthritis are also likely to develop another problem and that is foot ulceration. (Firth J, et al. Arthritis Care and Research. 2008;59:200-205).
"Foot ulceration affects 1 in 10 patients with RA and is often a recurrent problem affecting multiple sites in the foot," Dr. Jill Firth from the University of Leeds, the lead author of the study stated. "Clinical examination should include looking for early signs of tissue damage and intervening before ulceration occurs."
The researchers investigated the prevalence of foot ulceration in patients with RA under the care of rheumatologists.
Patients with diabetes, another cause of foot ulceration were excluded from the study. Reports from patients indicated that the point prevalence of foot ulceration in RA patients is 3.39%, and the overall prevalence is 9.73%, the investigators found.
One-third of the patients with ulcers reported multiple sites of ulceration, with the most common ulceration sites being the top part hammer toes (48%), metatarsal heads (32%), and the medial aspect of the first metatarsophalangeal joint (inside part of a bunion) (20%).
Nearly half the patients with ulcerations reported multiple episodes, ranging from 2 to 30 episodes, the researchers added.
Open and healed foot ulceration was associated with significantly longer disease duration, significantly greater usage of special footwear, and a higher prevalence of foot surgery.
The authors noted that foot ulceration has many clinical implications for the patient including increased pain, restricted choice of footwear, reduced mobility, and reduced participation in social activities all of lead to a negative impact on quality of life."
Other predisposing factors the researchers felt may lead to the ulcers include localized rheumatoid arthritis activity, anemia of chronic disease, vasculitis (inflammation of blood vessels), and medicine side effects.
As most clinicians know, patients with long-term disease where the feet have been involved often have the most problems with complications related to the feet.
"The aim of the prevalence study was to determine the size of the problem and to draw attention to the fact that this is an area which has received little clinical or research attention. The next step is to identify risk factors and to establish appropriate screening techniques and care pathways to provide evidence-based intervention," Dr. Firth went on to say.
Podiatry evaluation and assessment of footwear fit were another set of conclusions reached by the scientists.
The authors also made a point of mentioning that close attention should be paid to patients on anti-TNF therapies because soft tissue infection in an ulcer site may rapidly lead to life-threatening generalized sepsis if untreated.
