Total knee replacement

Why might this treatment be considered?

Total knee replacement may be considered when advanced osteoarthritis affects more than one part of the knee and causes substantial pain, stiffness, deformity or loss of function despite appropriate non-operative treatment. The aim is to improve pain and function—not simply to treat an X-ray. Some people continue to experience residual symptoms or dissatisfaction despite technically successful surgery, so expectations are discussed carefully.

What does the procedure involve?

During total knee replacement, the damaged surfaces at the end of the thigh bone and top of the shin bone are carefully prepared and resurfaced with metal components, usually with a polyethylene bearing between them. The kneecap may also be resurfaced when appropriate. Alignment, ligament balance and stability are checked before the wound is closed. Implant design and fixation are selected for the individual patient.

Potential benefits

• Substantial reduction in arthritic pain for most appropriately selected patients
• Improved walking, mobility and ability to perform everyday activities
• Correction of significant deformity and improvement in knee stability
• Better function, independence and quality of life

Reasonable alternatives

• Physiotherapy and an individual exercise programme
• Activity modification and pacing
• Weight optimisation where appropriate
• Pain relief or anti-inflammatory medication when medically suitable
• A walking stick, brace or other mobility aid
• A knee injection in selected circumstances
• Partial knee replacement when arthritis is suitably confined to one compartment
• Delaying or deciding not to have surgery

Important risks and limitations

Every procedure carries risk. The likelihood and importance of each risk vary between individuals.

• Bleeding, occasionally requiring transfusion
• Superficial or deep infection, which may require antibiotics, washout or revision surgery
• Blood clots in the leg (DVT) or lungs (PE), which may be life-threatening
• Wound or soft-tissue healing problems
• Pain, swelling, stiffness or a need for manipulation or further treatment
• Instability, altered movement or difficulty kneeling
• Ongoing pain or less improvement than hoped
• Fracture around the implant during or after surgery
• Wear or loosening of the replacement, with possible revision surgery
• Rare nerve or blood-vessel injury, including weakness such as foot drop that may be temporary or permanent
• Anaesthetic and medical complications including chest infection, heart attack or stroke, and a very small risk of death

Recovery and expectations

• Early mobilisation begins soon after surgery with support from the ward and physiotherapy teams.
• Pain, swelling, bruising and tiredness are expected initially; medication, ice, elevation and regular movement form part of recovery.
• Exercises and physiotherapy are important for restoring movement, strength, balance and confidence.
• Walking aids, blood-clot prevention, wound care and the timing of discharge are personalised; an overnight stay may be needed if pain or mobility limits same-day discharge.
• Improvement continues over several months. Progress is influenced by pre-operative stiffness, muscle strength, body weight, diabetes and general health.
• Return to driving, work and exercise is individual and should follow the clinical team’s advice.