Doctor's Notes on Osteoarthritis
Osteoarthritis (OA) is a degenerative joint disease that leads to the structural or functional failure of one or more joints. Osteoarthritis also involves progressive loss of cartilage. It can also affect the nearby muscles, the underlying bone, ligaments, joint lining (synovium), and joint cover (capsule). Osteoarthritis is the most common cause of chronic joint pain.
Symptoms of osteoarthritis may develop in one or more joints and include pain, aches, stiffness, and difficulty moving the joint. The pain may worsen with overuse and pain can occur at night. As the disease progresses, the pain may occur even when at rest. If the joints of the fingers and hands are affected by osteoarthritis, symptoms may include bone enlargements in the fingertips (first joint) called Heberden nodes that can develop suddenly and are painful, swollen, and red. Symptoms of osteoarthritis of the spine can include bone spurs or osteophytes, which can pinch or crowd nerves and cause pain and weakness in the arms or legs. Chronic low back pain (lumbago) may occur when osteoarthritis affects the lower spine.
The following signs and symptoms may be seen:
- Pain: Aching pain, stiffness, or difficulty moving the joint may develop in one or more joints. The pain may get worse with overuse and may occur at night. With progression of this arthritis, the pain can occur at rest.
- Specific joints are affected.
- Fingers and hands: Bone enlargements in the fingertips (first joint) are common. These are called Heberden nodes. They are usually not painful. Sometimes they can develop suddenly and are painful, swollen, and red. This is known as nodal osteoarthritis and occurs in women older than 45 years of age. Another typical joint affected is at the base of the thumb (basal thumb joint or first carpometacarpal joint). This can lead to difficulty gripping and turning keys and opening jars.
- Hip: The hips are major weight-bearing joints. Involvement of the hips may be seen more in men. Farmers, construction workers, and firefighters have been found to have an increased incidence of hip osteoarthritis. Researchers think that a heavy physical workload contributes to OA of the hip and knee.
- Knees: The knees are also major weight-bearing joints. Repetitive squatting and kneeling may aggravate osteoarthritis.
- Spine: Osteoarthritis of the spine can cause bone spurs or osteophytes, which can pinch or crowd nerves and cause pain and potentially weakness in the arms or legs. Osteoarthritis affecting the low back can lead to chronic low back pain (lumbago). Osteoarthritis in the spine leads to degenerative disc disease (spondylosis).
The causes of osteoarthritis include the following:
- Endocrine: People with diabetes may be prone to osteoarthritis. Other endocrine problems also may promote osteoarthritis development, including acromegaly, hypothyroidism, hyperparathyroidism, and obesity.
- Posttraumatic: Traumatic causes can be further divided into macrotrauma or microtrauma. An example of macrotrauma is an injury to the joint such as a bone break, causing the bones to line up improperly (malalignment), lose stability, or damage cartilage. Microtrauma may occur over time (chronically). An example of this would be repetitive movements or the overuse noted in several occupations.
- Inflammatory joint diseases: This category would include infected joints, chronic gout, and rheumatoid disease.
- Metabolic: Diseases causing errors of metabolism may cause osteoarthritis. Examples include Paget's disease and Wilson disease.
- Congenital or developmental: Abnormal anatomy such as unequal leg length may be a cause of osteoarthritis.
- Genetic: A genetic defect may promote breakdown of the protective architecture of cartilage. Examples include collagen disturbances such as Ehlers-Danlos syndrome.
- Neuropathic: Diseases such as diabetes can cause nerve problems. The loss of sensation may affect how the body knows the position and condition of the joints or limbs. In other words, the body can't tell when it is injured.
- Other: Nutritional problems may cause osteoarthritis. Other diseases such as hemophilia and sickle cell are further examples.
Cycling -- in a group or alone, outside or on a stationary bike -- builds stamina and balance with less impact on your knees, hips, and other joints than if you walk or jog. Recumbent models let you sit in a reclining position, and they might give you relief if you're uncomfortable on upright bikes. If you aren’t active now, check with your doctor before you start a new fitness program, so you know what’s OK for you to do.
Kasper, D.L., et al., eds. Harrison's Principles of Internal Medicine, 19th Ed. United States: McGraw-Hill Education, 2015.