Total Joint Replacement Surgery

The knee joint is comprised of the femur (thigh bone), patella (knee cap), and the tibia (shin bone), The hip is a ball and socket joint, made up of the femoral head (top of the femur) and the acebebulum, which is the socket in the pelvis. The ends of these bones are covered with articular cartilage. When this cartilage is worn down, the joint has developed arthritis, one of the most common causes hip and knee pain.

jointMore than 43 million people have some form of arthritis. It is estimated that the number of people affected by arthritis will increase to 60 million by 2020. The most common types are Osteoarthritis (OA), Rheumatoid Arthritis (RA), and Avascular Necrosis (AVN). When the arthritis is severe and other treatments are not working, hip and knee replacement is often the answer. Over 300,000 hip and knee replacements, respectively, are performed each year in the United States.

An estimated 27 million adults (roughly 8.9%) in the United States suffer from OA. This genetic condition is the most common form of arthritis, and it breaks down the cartilage that lines our joints. This condition can develop suddenly or very slowly over time, and can cause pain and stiffness in the joint affected. It may cause swelling, and can make the simplest of tasks very difficult to complete. In fact, about 80% of patients with OA have some degree of movement limitation.

RA, the most crippling form of arthritis affects approximately 2.1 million Americans. This condition is found two to three times more in women than men, with the average onset age ranging from 20 to 45 years old. The disease attacks the lining of the hip joint, and wears out synovium (soft tissue that lines the non-cartilaginous surfaces within joints), cartilage, and underlying bone.

Finally, AVN, or osteonecrosis, is a condition that cuts the supply of blood to the hip joint. Without adequate blood supply, the bone beneath the cartilage begins to die and the cartilage surface basically collapses. When this occurs in the hip, it can lead to a very painful type of arthritis.

There are various options for an individual who is suffering from an arthritic condition. Non-surgical methods include rest, ice, and heat applications, medications for inflammation and pain, lifestyle modification, physical therapy, and joint fluid supplements. Surgical options include knee arthroscopy, or total joint replacement.

A joint replacement is an option when the pain is so severe that it interferes with work or daily activities.

There are two types of knee joint replacements; total and partial. During a total knee replacement, the ends of the femur and tibia are replaced with metal, a plastic liner is inserted between the bones, and the patella is resurfaced with plastic. These components are typically cemented in place. Partial knee replacement is a procedure used when only part of a knee is arthritic. Typically, the medial, or inner part of the knee, is replaced. This can be associated with a quicker recovery than total knee replacement but is reserved only for patients with healthy bone structure and with arthritis in just one part of their knee.

During a hip replacement, the femoral head is removed and a stem is inserted into the femoral shaft. A ball on top of the stem articulates with an artificial socket that is implanted in the pelvis.

For those with severe arthritis that is limiting their quality of life, a hip or knee replacement can give patients their lives back. Today, these procedures have been found to result in significant restoration of function and reduction of pain in 90% to 95% of patients.

Post-surgical hospital stays generally last between two to three days. Patients begin to see significant functional improvement within four to six weeks, and maximum improvement is gained between six to twelve months. When fully recovered, patients can get back to their jobs and hobbies, with a dramatically improved quality of life.



This column was written by guest author Dr. Jeffrey Bush, M.D.