Osteoarthritis, also referred to as degenerative joint disease, occurs when the cartilage between the joint begins to wear and thin out. With prolonged suffering the bone may thicken and spur, meaning the surface of the bone is no longer smooth but jagged. Inflammation may occur as well. This makes ambulation painful and difficult. The knee is a common location for osteoarthritis due to the pressure applied to the joint and the amount of joint use.
Pain
Pain is the likely the most common initial symptom of arthritis of the knee. Generally the pain begins as a mild ache that worsens over time. Usually pain intensifies with activities such as walking. As the condition progresses, pain may prevent ambulation entirely or the individual may require assistive devices such as walkers or canes. Pain can occur as a result of decreased cartilage, inflammation or effusion.
Instability
Another symptom of osteoarthritis of the knee is instability. Instability may occur due to damage to the supportive structures of the knee joint. Individuals may find that walking is difficult due to joint weakness, and the joint may not be able to support the body's weight. Depending on the degree and duration of the condition, instability may occur sporadically or more frequently.
Swelling
Swelling and inflammation is another symptom commonly associated with the condition of knee arthritis. The individual may experience effusion, redness, tenderness and skin warmth at the site. Although uncomfortable, inflammation is a defense mechanism the body uses to protect against abnormal or harmful body tissues. According the Cleveland Clinic, this is a normal reaction to conditions such as arthritis.
Deformity
In severe cases over a prolonged period of time, individuals may experience deformity of the knee joint. Specific terms for the conditions are varus alignment of the knee and vargus alignment of the knee. In varus alignment, the stress, pressure and degenerative changes cause the knees to move inward toward each other. In vargus alignment the changes in the knee joint force the knee outward away from each other.
