What is joint replacement?

A joint is where two or more bones connect. Joint replacement (arthroplasty) is when a damaged joint is surgically removed and replaced with an artificial (prosthetic) joint by an orthopaedic surgeon. Prosthetic joints can be made of metal, plastic, or a mix of both. In other cases, rather than replace the whole joint, only the damaged parts are replaced or fixed.

The most common types of joint replacement surgery are for the hips and knees, but other joints such as the shoulders, fingers, elbows and ankles can also require surgery. 

Old couple cycling.Joint replacement surgery is most commonly performed for frequently-used joints such as the hips and knees. 

Orthopaedic

The medical specialty that look at deformities and diseases of the bones.

Reasons for procedure

The main reason for joint replacement surgery is joint pain, often due to arthritis, which affects an individual's quality of life and/or ability to perform daily activities. Joint replacement surgery is considered if the joint pain does not respond to other simpler treatment options. 

Types

There are many different types of joint replacement, including:

  • Hip joint replacement;
  • Knee joint replacement;
  • Shoulder joint replacement, and;
  • Hand joint replacement.

What happens during surgery

Before your surgeon performs your procedure, you will be given an anaesthetic to either block pain to the site of your surgery (regional anaesthesia) or to render you unconscious (general anaesthesia). Each procedure is different and depends on the site, technique, and how badly the joint is damaged. To replace a knee or joint it typically takes about two hours or less. 

Anaesthetic

A medication or other substance that causes a temporary loss of sensations, including pain.

What happens after surgery

Depending on the type of surgery, such as knee or hip surgery, you may need to stay in hospital for a few days. Pain medications are often needed for the first few days after surgery. Physical therapy is often needed to help strengthen the muscles around the new joint and regain motion in the joint. Usually you will be provided with a group of exercises to help with rehabilitation. 

Potential complications

Specific complications depend on the type of joint replacement surgery you are undertaking or have had, but in general they include:

  • Stiffness and swelling;
  • Blood clots - these result from inactivity during and after surgery and the slow flow of blood through the blood vessels;
  • Infection - all surgeries carry a small risk of infection and antibiotics may be taken after surgery to help reduce your risk of infection;
  • Nerve injury - although rare, there are many nerves around the joints and they can sometimes be damaged during surgery;
  • Fracture - although rare, during total joint replacement there is drilling into bone, which may cause the bone to fracture;
  • Implants failing or coming loose, and;
  • Joint dislocation - this is when joints pop out of place.

Antibiotics

Chemical substances that kill or suppress the growth of bacteria.

Infection

Entry into the body of microorganisms that can reproduce and cause disease.

Nerve

One or more fibres that transmit signals of sensation and motion between the brain or spinal cord and other parts of the body.

Clots

The thickened or solid mass formed from a liquid, such as blood. Blood clots normally form at an injury site to prevent further blood loss.

Prognosis

The outlook depends on the type of joint replacement surgery you have had. Doing physical exercises as prescribed by your surgical team will help improve outcomes, such as greater range of movement and stability of the joint. Depending on your age and circumstances, you may require more surgery in the future, with the majority of hip and knee replacements lasting about 20 years.