A 50-year-old woman presents with new complaint of pain in several fingers. She has had psoriasis for many years; however, she only developed joint pain last year. Her examination is significant for swelling and tenderness at the distal interphalangeal (DIP) joints of her second, third, and fourth fingers (Figure 95-1, A). She had an elevated erythrocyte sedimentation rate (ESR) and radiographs with erosive changes (Figure 95-1, B). Choices for therapy include methotrexate and the new biologic anti-tumor necrosis factor (TNF)-α medications.
Psoriatic arthritis at initial presentation in a 50-year-old woman with psoriasis and new-onset hand pain. A. Note the prominent involvement of the distal interphalangeal joints. B. Radiography showing early psoriatic arthritis changes with periarticular erosions seen at the distal interphalangeal joints. (Courtesy of Richard P. Usatine, MD.)
Arthritis means joint inflammation of the joints; however, the term is used for any disease or condition that affects joints or the tissues around the joints. Joint pain can be classified as monoarticular or polyarticular and inflammatory or noninflammatory. Diagnosis is based on a combination of clinical presentation, synovial fluid analysis, other laboratory tests, and radiographic findings. Management goals include minimizing joint damage, controlling pain, maximizing function, and improving quality of life.
- Fifty million adults in the United States (22%) report doctor-diagnosed arthritis.1
- Arthritis is the most common cause of disability in the United States. Twenty-one million adults have functional limitations because of arthritis.1
- Fifty percent of adults age 65 years or older have been diagnosed with arthritis.1
- One in every 250 children younger than the age of 18 have some form of arthritis.2
- In 2003, the total cost attributable to arthritic conditions was $128 billion.3
Arthritis can be caused by one of several mechanisms.
- Noninflammatory arthritis (i.e., osteoarthritis) is caused by bony overgrowth (osteophytes) and degeneration of cartilage and underlying bone (Figures 95-2 and 95-3).
- Autoimmune arthritis (i.e., rheumatoid arthritis, systemic lupus erythematosus [SLE], psoriatic arthritis) is caused by an inappropriate immune response.
- Crystalline arthritis (i.e., gout, calcium pyrophosphate dehydrate deposition disease) is caused by deposition of uric acid crystals (gout) or calcium pyrophosphate dehydrate crystals (CPPD) resulting in episodic flares with periods of remission.
- Septic arthritis is most commonly caused by bacteria (Neisseria gonorrhoeae, Staphylococcus, or Streptococcus; also gram-negative bacilli in immunocompromised patients and Salmonella in patients with sickle cell disease). Several viral illnesses may also have an associated arthritis.
- Postinfectious (reactive) arthritis is caused by an immune reaction several weeks after a urethritis or enteric infection.
- Fibromyalgia has an unknown etiology but includes abnormal pain perception processing.