Revision total knee replacement.

It is a more complex operation than a first knee replacement. Scar tissue, altered anatomy and possible bone loss all make it harder, and the reconstruction often requires specialised implants that were not needed the first time.

Dr John Limbers’ fellowship training in hip and knee replacement was undertaken at Addenbrooke’s University Hospital in Cambridge and Cappagh National Orthopaedic Hospital in Dublin, both high-volume centres where complex and revision knee work is concentrated. Revision knee surgery has remained part of his practice since, alongside a primary knee replacement practice of more than 5,000+ joint replacements.

A painful knee replacement is not automatically an indication for revision. Working out why it hurts is the substance of the assessment, and revision performed without a clear diagnosis frequently does not solve the problem.

• Aseptic loosening of one or more components
• Wear or damage to the polyethylene bearing
• Instability or recurrent giving way
• Persistent stiffness or loss of movement
• Infection around the joint replacement
• Fracture around the implant
• Malposition or mechanical problems
• Progressive bone loss
• Pain that has been carefully investigated and linked to a correctable cause

Symptoms can also arise from the hip, spine, tendons, nerves or other medical conditions, so thorough investigation is essential.

• Pain that never settled after the original surgery
• New pain in a knee replacement that had been comfortable
• Swelling, warmth or redness
• Any wound discharge, at any time after surgery
• The knee giving way or feeling unstable
• Progressive loss of movement
• Reduced walking distance after a period of doing well

Any wound discharge after joint replacement should be reported the same day.

Dr Limbers reviews the original operation, implant details, symptom pattern, examination and previous imaging. Investigations may include weight-bearing X-rays, CT, blood tests, nuclear imaging or joint aspiration where infection is a concern.

Infection must be identified or excluded before any revision is planned, because it changes the entire treatment plan.

Revision may involve replacing a single component or removing the entire knee replacement. The procedure starts with a CT scan before surgery, with a virtual revision total knee replacement being planned. During the procedure the patient’s anatomy and existing total knee replacement are registered, thus matching the patient’s anatomy to the plan. The revision total knee replacement plan is then modified to produce a well-balanced revision total knee replacement. Scar tissue is released as required and failed implants carefully removed. The remaining bone is then prepared under robotic control. Bone defects may need reconstruction using specialised revision components, stems, cones, augments or bone graft.

The final reconstruction is selected to provide stability while preserving as much remaining bone as possible. Infection-related revisions may require more than one operation.

Recovery is usually slower and less predictable than after a first knee replacement. Hospital stay, mobility aids and rehabilitation requirements depend on the complexity of the reconstruction, bone quality and general health.

Expect swelling, weakness and a gradual return of movement. Weight-bearing may occasionally be restricted, although most patients can walk with assistance soon after surgery.

Rehabilitation after revision knee replacement is individualised rather than protocol-driven, because what is safe depends on how much bone was reconstructed and how the implants are fixed. Dr Limbers provides instructions covering weight-bearing, movement and progression at discharge, and those instructions take precedence over any general guide.

View the Total Knee Replacement Rehabilitation Protocol →

Revision surgery carries higher risks than primary knee replacement, including infection, fracture, blood clots, stiffness, instability, nerve or blood vessel injury, wound problems, persistent pain, recurrent loosening and the need for further surgery.

The objective is generally to address a defined mechanical, infectious or implant-related problem. The revised knee may not feel or function like a normal knee, particularly where there has been significant bone or soft-tissue damage.