Total knee replacement, also known as total knee arthroplasty, is a surgical procedure in which a damaged or worn-out knee joint is replaced with an artificial joint, known as a prosthetic implant. This procedure is typically performed to alleviate severe pain and improve the overall function of the knee joint when other treatments, such as medications and physical therapy, have proven ineffective in managing the condition.
The knee joint consists of the femur (thigh bone), tibia (shin bone), and patella (kneecap). During a total knee replacement surgery, the damaged portions of these bones and cartilage are removed and replaced with prosthetic components made from metal, plastic, or a combination of both. The procedure aims to replicate the natural movement and function of the knee joint, allowing patients to regain mobility and reduce pain.
Sometimes the patella is not replaced if it is well preserved.
Candidates for total knee replacement surgery usually have conditions such as:
- Osteoarthritis: A degenerative joint disease that causes the cartilage between the bones to wear away, leading to pain, stiffness, and reduced mobility.
- Rheumatoid arthritis: An autoimmune disorder that affects the joints, leading to inflammation and damage.
- Traumatic injury: Severe fractures or injuries to the knee joint that result in significant damage to the bones and surrounding structures.
- Other conditions: Certain other forms of arthritis, such as post-traumatic arthritis or avascular necrosis, can also warrant knee replacement surgery.
The procedure involves several steps:
- Anesthesia: Patients are given anesthesia to ensure they are comfortable and pain-free during the surgery. The choice of anesthesia (general, regional, or local) depends on the patient’s health and the anaesthetist’s preference.
- Incision: The surgeon makes an incision over the knee joint to access the damaged joint components.
- Reshaping bones: The damaged surfaces of the femur and tibia are removed and reshaped to accommodate the prosthetic components.
- Implant placement: The artificial components, including metal caps for the femur and tibia and a plastic spacer for the kneecap, are attached to the prepared bone surfaces with cement or if their undersurface is especially coated to allow bone in growth into them without.
- Patellar resurfacing: Depending on the case, the undersurface of the patella might be resurfaced or left intact.
- Closure: The incision is closed using stitches or staples.
- Recovery and rehabilitation: After surgery, patients are monitored and gradually introduced to physical therapy to help them regain strength, flexibility, and mobility in the new knee joint.
It’s important to note that while total knee replacement can greatly improve a person’s quality of life, it is a major surgery with potential risks and complications, including infection, blood clots, implant loosening, and limited range of motion. Candidates for the surgery are carefully evaluated by medical professionals to determine if the benefits outweigh the risks.
Recovery time can vary, but most individuals can expect several weeks of rehabilitation to regain optimal function and mobility. Following the post-operative instructions provided by the surgical team and adhering to a rehabilitation program are crucial for successful outcomes.