What is a Joint Replacement?

Joint replacement is a surgical procedure in which a damaged or worn-out joint, typically due to arthritis or injury, is replaced with an artificial joint or prosthesis. The goal of joint replacement surgery is to relieve pain, improve joint function, and enhance the quality of life for individuals who have severe joint problems.

A joint is an articulation (junction) between 2 or more bones in the body. Muscles, tendons, ligaments, cartilage, and other soft tissue structures hold the joint in position.

The most frequently replaced joints are the hip, knee, and shoulder. Other joints, like the ankle, elbow, and finger joints, can also be replaced but are less common. The artificial joint, known as a prosthesis, is typically made of metal, ceramic, and/or plastic materials that are durable and compatible with the body.

Types of Joint Replacement

Total Joint Replacement: The entire joint is replaced with an artificial one.

Partial Joint Replacement: Only the damaged part of the joint is replaced, preserving as much of the natural joint as possible.

Indications for Joint Replacement

Joint replacement is typically recommended for the treatment of arthritis when other treatments, such as medication, physical therapy, or joint injections have failed to alleviate symptoms like chronic pain, stiffness, and decreased mobility. Arthritis is a condition in which the articular cartilage that covers the joint surface is damaged or worn out, causing significant pain, swelling, and stiffness in the joint. Joint replacement surgery is usually employed to treat symptoms of arthritis. The goal of the surgery is to relieve pain and restore the normal functioning of the joint. The two most common joint replacement surgeries are knee replacement and hip replacement.

Preparation for Joint Replacement

In general, preparation for joint replacement may include the following:

  • A thorough consultation with your orthopedic surgeon who will evaluate your joint condition, medical history, and overall health to determine if a joint replacement is suitable for you.
  • Detailed imaging studies, such as X-rays or CT scans to capture the joint anatomy in three dimensions. These images are used to design a customised surgical plan.
  • A review of your medications or supplements you are taking and any allergies you may have.
  • Your surgeon may instruct you to avoid certain medications and supplements that can thin the blood and increase the risk of bleeding during surgery.
  • You should not consume solids or liquids at least 8 hours prior to surgery.
  • A signed informed consent form will be obtained from you after the pros and cons of the surgery have been explained.

Procedure for Joint Replacement

In general, joint replacement surgery is performed under general or regional anaesthesia and typically involves the following steps:

  • The surgeon makes an incision over the joint to access the damaged area. The size and location of the incision depend on the joint being replaced and the surgical technique used.
  • The surgeon carefully separates the soft tissues and moves tendons and nerves aside to expose the damaged joint.
  • The damaged or diseased parts of the joint, including bone, cartilage, and any other structures that are no longer functional are carefully removed.
  • The surfaces of the bones are prepared to fit the new artificial joint components. This might involve shaping or smoothing the bone to accommodate the prosthesis.
  • The artificial joint components are inserted into the joint space. The components are designed to mimic the natural movement of the joint.
  • The prosthesis is secured to the bone using bone cement or a press-fit technique, where the prosthesis is designed to fit tightly into the bone. Over time, the bone may grow into the prosthesis to secure it further.
  • The surgeon carefully aligns the joint and tests its movement to ensure proper function and stability.
  • After confirming satisfactory repair, the soft tissues are repositioned, and the incision is closed with sutures or staples. A sterile dressing is applied to the wound.

Postoperative Care and Recovery

Postoperative care and recovery after joint replacement may include the following:

  • After joint replacement, the patient is typically placed in assistive devices such as casts, slings, crutches, or walkers to promote healing and facilitate mobility.
  • Early mobilisation is encouraged, often on the same day or the day after surgery to prevent complications such as blood clots or deep vein thrombosis (DVT).
  • The patient may experience pain, swelling, and discomfort in the treatment area. Pain and anti-inflammatory medications are provided as needed to address these.
  • The length of stay in the hospital varies, typically ranging from 1 to 3 days, depending on the joint replaced and the patient's overall health.
  • Activity guidelines are provided including refraining from lifting heavy weights and high-intensity activities for a defined period. 
  • A physical therapy protocol is started to restore range of motion, strength, and function to the joint.
  • Regular follow-up visits with the surgeon are scheduled to monitor progress and address any concerns.

Risks and Complications

Risks and complications associated with joint replacement include:

  • Infection
  • Bleeding
  • Pain
  • Blood clots or DVT
  • Implant loosening or failure
  • Nerve damage
  • General anaesthesia risks