Sunshine Coast Orthopaedic Group

Procedure · Knee · Revision arthroplasty

Revision knee replacement.

Replacing some or all of a knee replacement that has worn, loosened, become unstable, stiff or infected. As with the hip, establishing why it failed is more than half the operation.

Call (07) 5493 8038 How it is performed
Reviewed by Professor Daevyd Rodda Orthopaedic Surgeon · MBBS, Dip. Surg Anat, FRACS, FAOrthA Last reviewed: 21 August 2026
Type
Revision arthroplasty
Complexity
Higher than primary replacement
Hospital stay
3 to 7 nights, longer if infected
Implants
Often more constrained, sometimes stemmed
Recovery
3 to 12 months
Outcome
Improvement usual, less predictable than primary

What it is.

Australian registry data reports roughly 5 to 6% of knee replacements revised by ten years and about 10% by twenty. The common reasons differ from the hip.

  • Infection. A more common reason for revision in the knee than in the hip, because the joint is superficial with less soft tissue cover.
  • Aseptic loosening. Failure of fixation over time.
  • Instability. Ligament balance that is inadequate or has changed, producing a knee that feels unreliable.
  • Stiffness. Arthrofibrosis limiting movement, sometimes after an otherwise well-performed replacement.
  • Wear of the polyethylene bearing, sometimes revisable by exchanging the bearing alone.
  • Persistent unexplained pain. The most difficult category, and the one where revision is least likely to help. Revising a painful knee without a demonstrated cause frequently disappoints, and that is said clearly before any decision.

How it is performed.

Establishing the cause

Investigation includes serial radiographs, inflammatory markers, and aspiration where infection is possible. CT assesses component rotation and bone loss. Infection must be excluded before any revision is planned, because it changes the operation entirely.

The operation

  • Components are removed with careful preservation of bone. More bone is usually lost at this stage than at the primary operation.
  • Bone defects are managed with augments, metaphyseal cones or sleeves, or graft.
  • Revision implants are used, typically with stems that gain fixation in the shaft beyond the damaged bone.
  • Constraint is selected to match the ligaments. Where ligaments are deficient, a more constrained implant substitutes for the stability they no longer provide.
  • Balance and tracking are assessed through range before the final components go in.

Where infection is present

Usually a two-stage procedure: remove everything and place an antibiotic spacer, treat with targeted antibiotics guided by a microbiologist, then reimplant once the infection is controlled. This takes months rather than weeks.

Recovery timeline.

  • Hospital. Three to seven nights, longer for staged infected revisions.
  • Weeks 0 to 6. Weight bearing and range as specified for your operation. Full extension remains a priority.
  • Weeks 6 to 12. Progressive strengthening. Movement usually returns more slowly than after a primary replacement.
  • 3 to 12 months. Continued improvement. A year is a realistic horizon for the final result.

Outcomes.

Most patients improve, and the improvement is greatest where the reason for failure was clear and mechanical: a loose component, a worn bearing, a demonstrable instability. Those revisions do well.

Results are less predictable where the knee was painful without a demonstrated cause. Published series consistently show poorer outcomes in that group, which is why the cause is established before surgery is offered rather than after.

Range of movement after revision is typically a little less than after a primary replacement, and the risks of infection and further revision are higher. Complex revision may involve colleagues within Sunshine Coast Orthopaedic Group.

Rehabilitation.

Written specifically for your operation. In general:

  • Weeks 0 to 6. Extension first. Weight bearing exactly as specified. Protect any reconstruction.
  • Weeks 6 to 12. Progressive flexion and strengthening.
  • Beyond 12 weeks. Endurance, balance and function.

Protocols via For Physiotherapists.

Questions worth asking at your consultation.

Every one of these is a fair question and none of them should be awkward to ask. Print them or bring them on your phone.

  • Am I a good candidate for revision total knee replacement, and what would make me a poor one?
  • What are the alternatives, including doing nothing for now?
  • How many of these do you perform in a year?
  • What does the Australian registry say about the implant you would use for someone my age?
  • What does a realistic result look like for me specifically, and what will I still not be able to do?
  • What is your plan if it does not go well?

Frequently asked questions.

Why do knee replacements fail?

The commonest reasons are infection, loosening, instability, stiffness and wear of the polyethylene bearing. Infection is a relatively more common cause in the knee than in the hip because the joint is superficial with less soft tissue cover.

My knee replacement hurts but the X-ray is normal. Will revision fix it?

Often not, and this needs saying plainly. Revising a painful knee without a demonstrated cause has poorer published outcomes than revising one with a clear mechanical problem. The right first step is thorough investigation to find a cause, including excluding infection, rather than proceeding to surgery.

Will I get my movement back?

Range after revision is typically a little less than after a first replacement, and the starting point matters: a knee that was stiff before revision usually remains stiffer afterwards than one that moved well.

How long does recovery take?

Longer than a first replacement. Most of the gain is over three to six months, with improvement continuing to about a year.

Can just the plastic be changed?

Sometimes. Where the metal components are well fixed and correctly positioned and the problem is bearing wear, exchanging the polyethylene alone is a smaller operation. It is only appropriate in specific circumstances and it is confirmed during the operation.

References.

  1. Australian Orthopaedic Association National Joint Replacement Registry. Annual Report. Adelaide: AOA.
  2. Sharkey PF, Lichstein PM, Shen C, et al. Why are total knee arthroplasties failing today: has anything changed after 10 years? J Arthroplasty. 2014;29(9):1774-1778.
  3. Parvizi J, Gehrke T. Definition of periprosthetic joint infection. J Arthroplasty. 2014;29(7):1331.

This page provides general information about a medical condition and a surgical procedure. It is not individual medical advice and does not replace consultation with a qualified practitioner. Outcomes vary between individuals and all surgery carries risk. A referral is needed for a consultation with Professor Daevyd Rodda; without one, you can start with the practice nurse practitioner, who can provide it.