What is Total Knee Replacement?
Total knee replacement, also known as total knee arthroplasty, is a surgical procedure that replaces the damaged surfaces of the knee joint with artificial components. It is one of the most effective treatments for relieving pain and restoring function in patients with severe knee arthritis or joint damage.
During surgery, the worn ends of the thigh bone (femur) and shin bone (tibia) are carefully removed and replaced with smooth metal and plastic components. The end of the femur is shaped and fitted with a curved metal surface, while the top of the tibia is fitted with a flat metal plate and a plastic insert that acts as cartilage, allowing the knee to bend smoothly. The surgeon also adjusts the ligaments around the knee to ensure proper alignment and stability.
Knee replacement surgery may be total, where both sides of the joint are replaced, or partial (unicompartmental), where only one side of the knee is resurfaced.
.jpg)
Knee replacement is recommended for people with severe knee damage caused by conditions such as:
-
Osteoarthritis – the most common cause, where cartilage wears down with age.
-
Rheumatoid arthritis – an inflammatory condition that damages the joint lining.
-
Post-traumatic arthritis – following a fracture or injury to the knee.
-
Avascular necrosis – a loss of blood supply to the ends of the bones.
Surgery may be considered when:
-
Pain is constant, severe, and no longer relieved by medication or physiotherapy.
-
Walking, work, or daily activities are restricted by knee pain.
-
The joint is stiff, swollen, and deformed.
-
Pain disrupts sleep and overall quality of life.
-
X-rays show advanced arthritis or damage to the joint surfaces.
Who is Total Knee Replacement Surgery For?
Benefits of Total Knee Replacement
-
Pain relief: Significantly reduces or eliminates knee pain caused by arthritis or joint damage.
-
Mobility: Restores smooth movement and allows greater freedom of motion.
-
Strength and function: Improves stability, balance, and the ability to perform daily activities.
-
Quality of life: Helps patients return to walking, working, and recreational activities comfortably.
-
Durability: Modern implants typically last 15–20 years or more.
-
Patient satisfaction: Over 95% of patients report being very satisfied with their outcomes.
Risks and Complications
As with any major surgery, total knee replacement carries some risks. These include:
-
Infection: Occurs in about 1–2% of cases; antibiotics and sterile operating conditions greatly reduce the risk.
-
Blood clots: Prevented with early mobilisation and medication such as aspirin or anticoagulants.
-
Persistent stiffness: May require physiotherapy or further treatment to restore movement.
-
Wear of components: Implants are designed to last many years, but wear can occur gradually over time.
-
Nerve or vessel injury: Rare but possible during surgery.
-
General risks: As with any surgery, anaesthetic or medical complications can occur, though these are uncommon.
Although no operation can be guaranteed 100% successful, total knee replacement has an excellent success rate, with the vast majority of patients experiencing major improvements in comfort and function.
Before and After Surgery
Before surgery
Patients will undergo a full medical assessment, including blood tests and imaging such as x-rays. It’s important to inform the surgeon of all medical conditions, medications, and allergies. Smoking should be stopped at least two weeks before surgery, and any infections — including dental, bladder, or skin infections — should be treated beforehand.
Surgery
The operation usually takes about two hours and can be performed under general or spinal anaesthesia. Patients typically remain in hospital for two to four days. Modern anaesthesia and pain management techniques allow for early mobilisation, with many patients standing and beginning to walk the same day or the day after surgery.
Recovery
After surgery, patients use a Continuous Passive Motion (CPM) machine or guided physiotherapy to help regain movement in the knee. It’s common to use crutches or a walking frame for the first few weeks.
Most patients achieve 90 degrees of knee flexion before leaving hospital, and mobility continues to improve over time. Swelling and stiffness gradually lessen as recovery progresses, and most patients can resume driving and normal daily activities within six weeks.
