A joint is formed by the junction of two bones. Its function is to allow movement, and the surrounding tissues and muscles support and direct that movement. A joint becomes painful when it gets diseased and degenerates, which can be caused by old age, injury, infection, rheumatoid arthritis, gout, and other reasons. The most common cause is wear and tear due to old age. A diseased joint becomes swollen and red, with pain on movement and weight-bearing, plus stiffness, making day-to-day activities difficult.

The ends of bones are covered with smooth white cartilage, which allows free movement of the joint. When a joint becomes diseased, this cartilage is lost, leading to raw bone ends rubbing against each other. This causes severe pain and restriction of movement. Initially, medicines and exercises help, but joint damage progresses over time. Pain that occurs at night and disturbs sleep indicates serious joint damage requiring surgery. As cartilage cannot be regenerated, it is replaced with a smooth plastic-and-metal surface — joint replacement surgery.

The worn-out cartilage and frayed bone ends are replaced with a smooth metal and plastic surface. Movements become easier, pain on movement and weight-bearing goes away, muscle strength improves, and daily activities become easier. Surgical pain decreases in two to three weeks. Overall, surgery improves quality of life.

Joint replacement surgery is one of the most successful surgeries in modern medical history. There are routine risks like any operation: anaesthesia allergies, infection, kneecap displacement, deep vein thrombosis, and others — but these are minimised through careful planning and post-operative care.

The surgery itself normally lasts less than one hour. Preparation takes about one to one-and-a-half hours, and dressings, cleaning, and post-surgery X-rays take roughly one more hour. So relatives can expect to see their loved ones back after about three hours.