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Health condition

Periprosthetic joint infection, from MSIS diagnosis to staged revision.

A serious complication of hip, knee and other joint replacements - caught early it can often be treated without removing the implant.

Jump to treatment
A radiographer guides a patient onto the bed of an advanced 3 Tesla MRI scanner in a London imaging suite

Why trust this guide

  • 01

    Editorial team

    Written by our editorial team from the UK sources listed on each page.

  • 02

    Sourced from guidance

    Checked against BOA, MSIS and peer-reviewed sources you can see at the end.

  • 03

    Current for 2026

    Reflects modern UK practice including DAIR, one- and two-stage revision, and MDT-led antibiotic planning.

Key facts

Periprosthetic joint infection at a glance.

The essentials, in plain English - what it is, how it presents, and how it’s managed in the UK today.

  • What it is

    Infection of the tissue around a joint replacement - a serious cause of implant failure needing revision surgery.

  • Timing

    Early infection appears within weeks of surgery; late infection arrives months or years later, often from bloodstream spread.

  • Presentation

    Joint pain is the most consistent symptom - swelling, warmth, redness and, in chronic cases, a discharging sinus.

  • Diagnosis

    MSIS criteria combine blood markers, joint aspiration and, at surgery, tissue culture and histology.

  • Acute management

    Debridement, antibiotics and implant retention (DAIR) if caught early with a stable implant.

  • Chronic management

    Usually implant removal with one- or two-stage revision, plus prolonged targeted antibiotics.

Why this guide matters

Getting the diagnosis right, early.

Periprosthetic joint infection is uncommon but serious - with the right approach at the right stage, implants and function can often be saved.

  • Timing changes everything

    Acute infection caught early with a stable implant opens the door to DAIR - chronic infection usually needs full revision.

  • Diagnosis is a team effort

    MSIS criteria bring together blood tests, joint aspiration and tissue culture - no single test is enough alone.

  • Antibiotics alone rarely cure it

    Bacteria form a biofilm on the implant surface - surgery to address the hardware is usually part of a lasting cure.

How the diagnosis is made

From first symptoms to a confirmed plan.

The steps a UK orthopaedic team will normally follow, in order - so you know what to expect and why.

  1. 01

    Assessing

    Clinical assessment

    Joint pain, swelling, warmth, erythema and reduced range of motion are reviewed alongside the timing since surgery.

  2. 02

    Assessing

    Inflammatory markers

    CRP and ESR are checked - raised markers support the diagnosis but are not specific on their own.

  3. 03

    Assessing

    Joint aspiration

    Synovial fluid is sent for white cell count and culture - a cornerstone of diagnosis and organism identification.

  4. 04

    Confirming

    Imaging

    X-ray looks for loosening; MRI or nuclear medicine scans are sometimes added for equivocal cases.

  5. 05

    Confirming

    Specialist MDT review

    Orthopaedic and infectious diseases specialists jointly weigh the evidence given how complex the diagnosis can be.

  6. 06

    Planning

    Intraoperative culture and histology

    At revision surgery, multiple tissue samples confirm infection and identify the causative organism definitively.

  7. 07

    Planning

    Treatment planning

    DAIR, single-stage or two-stage revision is chosen based on chronicity, implant stability and organism.

Typical timeline: days for acute assessment, longer where revision surgery is planned.

Symptoms

What periprosthetic joint infection actually looks like.

Early infection is often dramatically symptomatic. Chronic, low-grade infection can be far more subtle - and easy to miss.

  • Persistent joint pain

    Often the most consistent symptom - present in both acute and chronic infection, sometimes the only sign.

  • Swelling

    New or worsening swelling around the joint, especially after an initially uneventful recovery.

  • Warmth around the joint

    Increased local temperature compared with the other side is a useful bedside clue.

  • Erythema

    Redness of the skin overlying the prosthesis - more prominent in acute, early infection.

  • Wound discharge or sinus tract

    A persistently discharging wound or sinus in chronic infection is essentially diagnostic on its own.

  • Fever and systemic illness

    More common in acute infection - chills, malaise and feeling generally unwell alongside the joint symptoms.

  • Reduced range of motion

    Stiffness and loss of movement beyond what is expected for the stage of recovery.

  • Red flag - subtle chronic infection

    Low-grade chronic infection can be subtle, with vague pain and no fever - don’t dismiss it.

Treatment

How periprosthetic joint infection is treated in the UK.

DAIR for early, stable infection - staged revision and prolonged targeted antibiotics for chronic disease, all led by a specialist MDT.

  • DAIR

    Debridement, antibiotics and implant retention - for acute infection caught early with a stable, well-fixed implant.

  • Two-stage revision

    Implant removal, an antibiotic-loaded cement spacer, a course of targeted antibiotics, then reimplantation once infection has cleared.

  • One-stage revision

    Implant removal and reimplantation in a single procedure - selected cases with known organisms and good soft tissue.

  • Antibiotic spacer

    A temporary cement spacer loaded with antibiotics fills the joint space and delivers local treatment between stages.

  • Targeted antibiotic therapy

    Prolonged treatment, often 6 weeks or more, guided by culture results and directed by specialist microbiology.

  • Suppressive antibiotics

    Long-term, lower-dose antibiotics when revision surgery is not feasible - controls rather than cures the infection.

  • Orthopaedic-microbiology MDT

    Joint decision-making across specialist commissioned orthopaedics and infectious diseases teams shapes every step.

  • Post-revision rehabilitation

    Structured physiotherapy after revision surgery to restore strength, function and confidence in the joint.

What this guide is based on

The sources behind every claim on this page.

UK national guidance and specialist society standards, current at the time of last review.

Key references

Guidelines and standards we relied on.

A quiet reminder

This guide is for information, not medical advice.

Your orthopaedic surgeon knows your implant and history and can tell you which parts apply to you. If in doubt, get seen.

  • British Orthopaedic Association (BOA). Standards for periprosthetic joint infection.

  • Musculoskeletal Infection Society (MSIS). Diagnostic criteria for periprosthetic joint infection.

  • National Joint Registry (NJR). Annual report - revision surgery and infection data.

  • Public Health England / UKHSA. Surgical site infection surveillance guidance.

Red flags

When it needs urgent attention.

Most suspected infection needs prompt review. These are the situations that need it immediately.

  • Sepsis or systemic sepsis

    Fever, tachycardia, confusion or falling blood pressure alongside a hot, painful joint needs emergency assessment.

  • Acutely unstable implant

    Sudden inability to weight-bear or a clearly loose prosthesis on imaging warrants urgent orthopaedic review.

  • Rapidly discharging sinus

    A new or worsening discharging wound over a prosthesis should be seen the same day, not watched.

  • Early post-operative deterioration

    Worsening pain, wound issues or fever in the first weeks after joint replacement needs prompt reassessment.

  • Multi-resistant organisms

    MRSA or other resistant organisms on culture change the antibiotic plan and need specialist microbiology input early.

  • Bacteraemia from another source

    Bloodstream infection elsewhere - dental, urinary, skin - can seed a prosthetic joint even years after surgery.

  • Failed DAIR

    Ongoing infection despite debridement and antibiotics usually means escalation to staged revision is needed.

  • Immunosuppression

    Diabetes, rheumatoid disease or immunosuppressive drugs raise infection risk and blunt the usual warning signs.

  • Delayed presentation of chronic infection

    Long-standing low-grade pain dismissed as "wear" can be chronic infection - persistent symptoms deserve investigation.

Living with it

A serious complication, with a clear pathway.

Four things that make the biggest difference through diagnosis and recovery - staying alert, protecting against seeding, finishing antibiotics and committing to rehab.

A quiet reminder

Early recognition changes the treatment options available.

The earlier acute infection is caught, the more likely the original implant can be kept.

  1. 01 Vigilance

    Know your normal

    Learn what your joint felt like once it settled, so new pain, swelling or warmth stands out early.

  2. 02 Hygiene

    Protect against seeding

    Treat dental work, skin infections and urinary symptoms promptly - bacteraemia can seed a prosthesis years later.

  3. 03 Adherence

    Complete the antibiotic course

    Targeted therapy often runs 6 weeks or more - stopping early risks relapse and harder-to-treat infection.

  4. 04 Rehab

    Commit to rehabilitation

    Function after revision surgery depends heavily on consistent physiotherapy in the months that follow.

Frequently asked

Everything we get asked about periprosthetic joint infection.

Quick answers on diagnosis, DAIR, revision surgery and antibiotic treatment.

  • What is periprosthetic joint infection?

    Infection of the tissue surrounding a joint replacement, such as a hip or knee prosthesis. It is one of the most serious complications of joint replacement surgery and a significant cause of implant failure requiring revision.

  • How soon after surgery can it happen?

    Early infection typically appears within weeks of the original operation. Late infection can occur months or years later, usually from bloodstream spread of infection from elsewhere in the body, or from a low-grade chronic infection that was present from the start.

  • How is it diagnosed?

    Diagnosis follows MSIS criteria, combining inflammatory markers (CRP, ESR), joint aspiration for synovial fluid white cell count and culture, imaging, and intraoperative tissue culture and histology at revision surgery. It is assessed by a specialist orthopaedic and infectious diseases MDT.

  • What is DAIR?

    Debridement, antibiotics and implant retention - a treatment used for acute infection when the implant is still stable and the infection is caught early. It avoids removing the prosthesis but is not suitable for chronic or long-standing infection.

  • Why do some people need two operations instead of one?

    Two-stage revision removes the infected implant, places an antibiotic-loaded spacer, treats with targeted antibiotics, then reimplants a new prosthesis once infection has cleared. It is generally used for chronic infection and gives infection more time to be eradicated than a single-stage approach.

  • How long does antibiotic treatment last?

    Prolonged, culture-guided therapy is typical - often 6 weeks or more - with specialist microbiology input throughout. If revision surgery is not feasible, long-term suppressive antibiotics may be used instead to control rather than cure the infection.

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