Total Knee Replacement (TKR)

What is a Knee Replacement?

Total Knee Replacement (also called knee arthroplasty) is a surgical procedure to replace a worn, painful, or damaged knee joint with an artificial implant. It is most commonly offered when pain and stiffness from conditions like osteoarthritis have not responded to non-surgical treatments.

Total Knee Replacement involves removing the arthritic surfaces of the tibia (shin bone) and femur (thigh bone), to restores the knee to its natural alignment, improves mobility and helps significantly reduce pain.

There are two main types:

Total Knee Replacement (TKR) — replaces all major surfaces of the knee.
Partial Knee Replacement (PKR) — Sometime call Uni Knee Replacement, replaces only the part of the joint that is damaged, preserving as much of the rest of the knee as possible. [See Partial Knee Replacement]

Who Might Need Knee Replacement?

You may be considered for a knee replacement if:

You have severe knee pain or stiffness that limits everyday activities.
Pain that regularly interferes with sleep or quality of life.
Conservative treatments like medication, physiotherapy, injections, weight management, or walking aids aren’t enough.

Every patient is assessed individually, and surgery is only recommended when the potential benefits outweigh the risks.

Common Symptoms & Daily Impact

Signs that knee replacement might be worth discussing include:

Persistent pain during walking, climbing stairs, or standing.
Swelling and stiffness that limits range of motion.
Knee deformity or instability.
Difficulty with routine tasks you used to manage independently.

The Procedure

This procedure, including the anaesthetic and recovery, typically takes 1.5 to 2 hours. Most patients receive a spinal anaesthetic, along with sedation to ensure they remain unaware of the surgery. Sensory nerve blocks are also used to ensure you are as pain free as possible.

An incision is made along the front of the knee, and the arthritic bone is removed and replaced with metal and plastic components. To reduce post-operative pain, a local anaesthetic is applied around the knee. The incision is closed and a dressing is applied. A bandage and ice are used to manage any swelling and bruising.

Recovery & Rehabilitation — What to Expect

After surgery, most patients experience minimal discomfort and are encouraged to start using the knee straight away. It’s safe to walk on the knee immediately, and physiotherapists will guide you on how to do so safely and to begin activating your quadriceps muscle.

The typical hospital stay is now only 1 night due to improvements in anaesthetic techniques and strong evidence of improved outcomes in patients who are mobilising normally as quickly as possible.

Recovery varies from person to person, but most people progress through these phases:

Early recovery (0–6 weeks)

Pain and swelling gradually improve.
Begin walking with assistance (crutches or frame) soon after surgery.
Physiotherapy starts early to restore movement and strength.
Key focus in these early weeks is achieving full extension of the knee

Medium phase (6–12 weeks)

Most patients can walk more confidently without aids.
Daily activities return gradually.
Continued physiotherapy helps build strength and flexibility.

Long-term recovery (3–12+ months)

Continued improvement in comfort and activity levels.
Some recovery of strength and function may continue up to 12–18 months.

Expected Outcomes

Most patients experience significant pain relief and improved mobility after knee replacement.

Many individuals report excellent satisfaction and return to everyday activities with less discomfort. The key to this is working hard restoring range of movement and strength quickly to the knee after surgery.

Pain management is essential to ensure you are adequately pain free to enable you to carry out range of movement exercises every day. Many patients also recommend getting a small skateboard to use to move the knee through a full range of movement multiple times throughout the day.

Modern implants and surgical techniques have excellent long-term outcomes, with many lasting 20+ years in appropriately selected patients.

Preparing for Surgery

Preparation helps optimise your recovery:

Prehabilitation exercises to strengthen leg muscles.
Managing medical conditions such as diabetes or high blood pressure.
Getting weight to within safe limits to make the surgery and anaesthetic as safe as possible.
Talking with other patients who have undergone knee replacement to get a full and honest overview of the surgery and the recovery.

Please see Total Knee Replacement Rehabilitation Videos for advice on how to best recover following Total Knee Replacement.

Frequently Asked Questions?

When can I walk after surgery?
Most patients begin walking on the day of surgery with physiotherapy support.

When can I drive again?
Typically around 6–8 weeks after surgery when you have good control, strength, and can perform an emergency stop safely.

How long before I return to work?
Return to work depends on your job and recovery progress — many sedentary roles by 6–8 weeks, more physically demanding work later.

Swelling After Knee Replacement – What’s Normal?
Swelling of the lower leg, ankle and foot is very common after knee replacement surgery. It can fluctuate through the day and may take weeks (and sometimes months) to fully settle. This swelling is often due to normal post-operative inflammation and fluid settling in the lower leg, especially when you have been sitting or standing for longer periods.

A useful guide is that normal swelling often improves overnight and with elevation, and is typically worse towards the end of a day.