Arthritis

This is a degenerative disease that causes progressive loss of articular cartilage in the knee. It can be associated with a traumatic injury to the knee, certain occupations that involve repetitive knee bending, muscle weakness and large body mass. 

Osteoarthritis can present with symptoms of function-limiting knee pain, effect on walking distance, pain at night or rest, activity induced swelling, knee stiffness, instability, locking, and a catching sensation.

Osteoarthritis is by far the most common cause of cartilage degeneration in the knee, but there are a number of other conditions which can lead to joint disease. Inflammatory conditions, such as rheumatoid arthritis, are largely treated with disease modifying medications, prescribed by a specialist rheumatologist, but occasionally they do require joint replacement surgery. I would be happy to offer advice regarding this.