In plain language
What is conventional total knee replacement?
A total knee replacement does not remove the whole knee. The surgeon removes a thin layer of worn bone and cartilage from the end of the thigh bone and top of the shin bone, then caps these surfaces with metal components. A strong plastic spacer sits between them so the joint can move smoothly.Who it may help
When might it be considered?
- Advanced knee osteoarthritis with pain on most days
- Night pain, stiffness, deformity or loss of walking distance
- Difficulty with stairs, chairs, work or meaningful daily activity
- Symptoms that remain unacceptable after reasonable nonsurgical care
Before surgery
What may be considered first?
- Exercise-based rehabilitation and strength work
- Weight optimisation and activity modification
- Medication, walking aids and selected injections
- Partial knee replacement or joint-preserving surgery in carefully selected patients
Inside the operating theatre
What actually happens during the operation?
Confirming the pain source
Standing X-rays, examination and the pattern of symptoms must agree. Back, hip or soft-tissue pain can mimic knee arthritis and should not be overlooked.
Preparing the bone surfaces
Through an incision at the front of the knee, the surgeon moves the kneecap aside and removes only the damaged surface layers from the femur and tibia using measured guides and surgical instruments.
Balancing the knee
The ligaments are assessed so the knee is stable and can straighten and bend. Trial components help the surgeon check alignment, movement and soft-tissue balance.
Fitting the implants
A metal cap is fixed to the femur and a metal tray to the tibia, usually with bone cement. A medical-grade plastic insert locks into the tibial tray. The underside of the kneecap is resurfaced only when clinically appropriate.
Closure and early movement
After final checks the wound is closed and covered. Pain control, circulation exercises and assisted walking begin early because movement is part of recovery.
After the operation
What does recovery involve?
Swelling, bruising, disturbed sleep and stiffness are common in the first weeks.
Early goals are full straightening, progressive bending, quadriceps activation and safe independent walking.
Strength and endurance continue improving for months. A knee replacement is intended for reliable daily function; high-impact sport may not be recommended.
Informed consent
Important risks to understand
- Infection
- Blood clots
- Stiffness
- Persistent pain or swelling
- Nerve or blood-vessel injury
- Fracture or instability
- Implant wear, loosening or revision surgery
This is a general guide, not a complete consent discussion. Your surgeon will explain risks specific to your diagnosis, health, anatomy and proposed technique.
Common patient questions
Questions people often ask
Is the kneecap always replaced?+
Not always. The surgeon assesses its cartilage, shape and tracking and decides whether resurfacing is appropriate.
How much bend should I expect?+
Pre-operative movement strongly influences final movement. The usual aim is enough bend for stairs, chairs and a car, together with the ability to straighten the knee well.
Will the knee feel completely natural?+
Many patients gain major pain relief and function, but a replacement may feel different from a native knee. Clicking, skin numbness and awareness of the joint can occur.
Clinical references
These independent patient resources informed the general explanation above.