Knee arthritis

This occurs when the joint surface cartilage (also called hyaline cartilage, or articular cartilage) becomes worn away, leaving the raw bone beneath exposed (See Fig 1). The cartilage normally serves as a “pad” or a bearing in the joint, and under normal conditions, the cartilage bearing is even slicker than a hockey puck on ice. When the bearing wears away, the result is a roughed joint surface that causes the pain and stiffness that people associate with osteoarthritis (See Fig 2 and Fig 3).

For most patients who have only mild arthritis, the pain can be managed with simple things such as ice, rest, activity modifications, pills, or joint injections.

However, if the arthritis becomes severe (See Fig 4 and Fig 5), the pain may not respond to those kinds of interventions. Patients with severe arthritis sometimes can benefit from joint replacement surgery, either partial (unicompartmental) knee replacement or total knee replacement (See Fig 6), which now can be done using a minimally-invasive quadriceps-sparing approach that can significantly shorten the recovery and decrease the pain following surgery.

Immediate medical attention

Osteoarthritis of the knee is not an emergency. It can, however, result in disturbing “flare ups,” with increased pain and swelling. Many patients who experience a sudden flare-up will go to the doctor for care, and for many patients this apparently “acute” set of symptoms will result in the diagnosis of this chronic condition.

Facts and myths

MYTH: Osteoarthritis of the knee is not usually the result of “overuse.” there have been studies of long-distance runners that show that they are not more likely to get arthritis than more sedentary individuals.

MYTH: Osteoarthritis of the knee is not a “normal result of aging.” Many older people – in fact, most – don’t develop arthritis of the knee, and many younger people do experience osteoarthritis.

MYTH: Osteoarthritis of the knee is not just “aches and pains.” It is a condition whose biology, x-ray appearance (See Fig 4), and clinical symptoms are defined.