Single-stage exchange revision for chronic PJI in selected patients · advanced
- One-stage revision is appropriate only when the organism is known preoperatively and susceptible to biofilm-active antibiotics, the patient is immunocompetent, the soft tissues are healthy without a sinus tract, and bone stock permits immediate reimplantation — these are the Endo-Klinik selection pillars.
- The defining technical step is the mandatory complete re-draping, re-gowning and opening of an entirely new sterile instrument set after explantation and debridement — this prevents recontamination from the infected field and is what makes it a true one-stage protocol.
- Antibiotic-loaded cement (typically 2-4 g antibiotic per 40 g cement, chosen according to susceptibility) is used for fixation; systemic antibiotics are continued for 4-6 weeks postoperatively with close infectious-disease input.
- Reinfection rates after carefully selected one-stage revision are reported in the 5-15 percent range at 5-10 years, comparable to two-stage exchange in appropriately chosen patients, with the advantage of a single anaesthetic exposure and faster functional recovery.
When & Why
One-stage exchange revision removes the infected prosthesis, radically debrides the joint, and reimplants a new prosthesis — all in a single operation, with antibiotic-loaded cement. It is reserved for chronic periprosthetic joint infection (symptoms greater than 4 weeks) in a strictly selected patient. Acute postoperative or haematogenous PJI is managed by DAIR (debridement, antibiotics and implant retention); complex chronic PJI is managed by two-stage exchange. One-stage sits in the middle — for the well-defined, favourable chronic case. Absolute indications — the Endo-Klinik selection pillars. All five must be present: - A single, known, susceptible organism identified on preoperative aspiration or biopsy
- An immunocompetent host with well-controlled comorbidities and no active systemic infection
- A healthy soft-tissue envelope without sinus tract, abscess or significant scarring
- Adequate bone stock permitting immediate stable reimplantation without major structural augments
- An organism susceptible to biofilm-active antibiotics that can be delivered both locally (in cement) and systemically Relative indications include patient preference for a single anaesthetic after informed discussion, low-virulence organisms (coagulase-negative staphylococci, Cutibacterium, streptococci) with proven susceptibility, and well-fixed implants with minimal bone loss. Absolute contraindications — each of these excludes one-stage and demands two-stage (or, for acute disease, DAIR):
A sinus tract is a chronic fistulous communication with skin flora and guarantees polymicrobial or resistant contamination. Any sinus tract mandates two-stage exchange with excision of the tract and a temporary spacer.
Without a preoperative culture you cannot select the local and systemic antibiotics. Resistant organisms (MRSA, VRE, fungi, multidrug-resistant Gram-negatives, rifampicin-resistant staphylococci) are managed by two-stage protocols or suppressive therapy.
Chemotherapy, high-dose steroids or biologics, uncontrolled diabetes (HbA1c greater than 8 percent), dialysis, or HIV with low CD4 — host immunity cannot clear residual biofilm. Two-stage exchange with prolonged antibiotic holiday and optimisation is preferred.
Major bone loss (Paprosky III or greater acetabular or femoral deficiency, or AORI 3 about the knee) precludes stable immediate fixation. Assess with CT and convert to two-stage with a spacer; plan augments or flaps at reimplantation.
If coverage will require a flap, one-stage is not appropriate — insert a spacer and reconstruct the soft tissues first.
Relative contraindications are acute postoperative or haematogenous PJI (DAIR indications), a previous failed one-stage revision, and a patient unable to comply with prolonged antibiotics or follow-up.
Do not attempt one-stage revision in the presence of a sinus tract, an unknown organism, a resistant pathogen, or an immunocompromised host — these are absolute contraindications. If any selection pillar is missing, default to two-stage exchange. One-stage is never appropriate for acute postoperative or haematogenous PJI; those are managed with DAIR and implant retention.
One-stage versus two-stage — the decision framework. When the patient is suitable for both, the choice balances organism certainty, host fitness, bone and soft-tissue quality, and the patient's preference for a single versus staged procedure.
- One-stage exchange
- Mandatory
- Two-stage exchange
- Preferred but not mandatory
- One-stage exchange
- Absolute contraindication
- Two-stage exchange
- Acceptable with tract excision
- One-stage exchange
- Contraindicated
- Two-stage exchange
- Preferred approach
- One-stage exchange
- Contraindicated
- Two-stage exchange
- Standard management
- One-stage exchange
- One
- Two-stage exchange
- Two (or more if spacer exchange)
- One-stage exchange
- Shorter (typically 7-14 days)
- Two-stage exchange
- Longer (spacer phase plus reimplantation)
- One-stage exchange
- Faster (no spacer interval)
- Two-stage exchange
- Slower (spacer complications possible)
- One-stage exchange
- 5-15 percent at 5 years
- Two-stage exchange
- 5-15 percent at 5 years
Preoperative workup. Every candidate undergoes a standardised workup to confirm infection, identify the organism, and assess host and local factors. Serum CRP and ESR (both elevated supports infection, but normal values do not exclude low-grade infection) with full blood count, renal and liver function, HbA1c and nutritional markers (albumin, prealbumin). Preoperative aspiration under sterile conditions (fluoroscopy- or ultrasound-guided for hips) gives a cell count and differential (greater than 3000 white cells per microlitre or greater than 80 percent neutrophils supports chronic infection), culture and sensitivity (aerobic, anaerobic, fungal), and alpha-defensin or leukocyte esterase where available. Plain radiographs assess implant fixation, bone stock and osteolysis; a metal-artefact-reduced CT classifies bone defects (Paprosky for the hip, AORI for the knee). Optimise the host first — glycaemic control, smoking cessation, nutritional repletion, and temporary cessation of immunosuppressants where safe — and obtain an infectious-disease opinion for antibiotic planning. Setup. Position depends on the joint: supine on a radiolucent table for the knee, lateral decubitus for the hip posterior approach. Full limb preparation and draping allows extensile exposure if needed. Regional (spinal or epidural) with sedation or general anaesthesia, with invasive monitoring for prolonged cases and the infectious-disease team available for real-time advice. Hold systemic antibiotics until after the deep tissue samples are obtained — then give targeted intravenous antibiotic based on the preoperative culture.
The Operation
The goal is to confirm and sample the infection, remove all implants and foreign material, radically debride the joint, eliminate recontamination by completely re-draping and changing instruments, and reimplant a new prosthesis fixed with antibiotic-loaded cement — all in one sitting. The exposure is laid out in full below as the first steps: it is the foundation on which a complete debridement depends.
Operative sequence
- Supine on a radiolucent table for the knee; lateral decubitus for the hip posterior approach. Full limb prep and drape for extensile access.
- Regional (spinal/epidural) with sedation or general anaesthesia; invasive monitoring for long cases; infectious-disease team on standby.
- Hold systemic antibiotic until the deep tissue samples are taken, then administer the targeted agent based on the preoperative culture.
- Use the previous surgical approach or an extensile approach as required, with a complete capsular incision.
- Hip — posterior approach. Identify and protect the sciatic nerve, which lies posterior to quadratus femoris — keep the hip extended and the knee flexed to relax it. Tag the gluteus maximus tendon insertion and the short external rotators; the posterior capsule and external rotators provide important stability and must be repaired meticulously after reimplantation. Assess acetabular and femoral bone stock now — it governs whether immediate reimplantation is feasible.
- Knee — medial parapatellar approach. Preserve the extensor mechanism and avoid excessive lateral retinacular release. Expose the medial collateral ligament and posteromedial capsule for complete debridement and protect the patellar tendon throughout — if exposure is difficult, use a quadriceps snip or tibial tubercle osteotomy. The competence of the collateral ligaments after debridement will set the implant constraint you need.
- Open the capsule completely and inspect the joint.
- Obtain a minimum of five deep tissue samples from representative sites — synovium, membrane and the bone-implant interface — before any antibiotic is given.
- Send samples for aerobic, anaerobic and fungal culture plus histology. These guide the final antibiotic choice even when preoperative aspiration has already identified the organism, because culture yield drops sharply once antibiotics are administered.
- Remove all implants using appropriate extraction tools.
- Remove all cement, screws, wires and suture material — no foreign body is left behind.
- Confirm there is no retained cement or hardware on fluoroscopy before moving to debridement.
- Excise the entire pseudocapsule, the synovial membrane and any necrotic or scarred tissue.
- Use high-speed burrs and curettes to debride the bone surfaces thoroughly back to healthy, bleeding bone.
- Perform extensive pulsatile lavage with at least 9 litres of fluid.
- Reassess bone stock and soft-tissue coverage — if a contained, stable bed cannot be achieved, abandon one-stage and place a spacer.
- Remove all drapes. The whole surgical team re-scrubs and re-gowns.
- Apply completely new sterile drapes.
- Open an entirely new sterile instrument set and new implants.
- This single manoeuvre prevents recontamination of the new prosthesis by bacteria carried over on drapes, gowns or instruments from the infected field — it is the defining technical feature of a true one-stage protocol and the most common step omitted when one-stage cases fail early.
- Prepare the bone surfaces for cemented fixation.
- Mix antibiotic-loaded cement according to organism susceptibility — commonly gentamicin, vancomycin or tobramycin at 2-4 g per 40 g cement; a common Gram-positive combination is gentamicin plus vancomycin.
- Implant the new prosthesis with the antibiotic-loaded cement.
- For the knee, use a constrained condylar or hinged implant if the collateral ligaments were compromised during debridement; for the hip, uncemented stems with cemented cups or hybrid constructs are used when bone quality permits, while fully cemented constructs remain acceptable.
- Verify stability, limb length and range of motion before final closure.
- Perform a final lavage and close in layers with absorbable sutures, over drains if indicated.
- Apply a sterile dressing and transfer to recovery with the targeted intravenous antibiotic continued.
- Monitor for early signs of recurrent infection — wound drainage, fever, a rising CRP.
The single greatest technical danger is proceeding to reimplantation without complete re-draping and a brand-new instrument set — the new prosthesis is then recontaminated by the infected field and early reinfection follows. Other dangers at this stage: inadequate debridement leaving residual membrane or cement (a persistent source of infection), choosing the wrong antibiotic in the cement or systemic regimen (treatment failure), and overlooking bone defects that compromise immediate fixation (early loosening). Physically remove every drape, re-scrub, and open a new set before any reimplantation.
After explantation and thorough debridement, remove every drape, re-scrub and re-gown, apply completely new drapes, and open an entirely new sterile instrument set before reimplantation. This is the hallmark of a true one-stage protocol and the step examiners expect you to describe explicitly — its omission is the commonest technical reason for early reinfection after a purported one-stage procedure.
Aftercare & Complications
Rehabilitation | Phase | Timing | Weight-bearing | Therapy and antibiotics | |-------|--------|----------------|-------------------------| | 1 | Day 0-1 | Protected — partial (hip) or toe-touch (knee) | Mobilise under physiotherapy; begin targeted intravenous antibiotic | | 2 | Weeks 1-6 | Progressive as tolerated with crutches | Range of motion and quadriceps strengthening (knee); weekly CRP | | 3 | Weeks 6-12 | Full weight-bearing | Resistance training and gait normalisation | | 4 | Months 3-12 | Unrestricted | Graded return to function; clinical and radiographic review at 3, 6 and 12 months | Antibiotic course. Four to six weeks of targeted intravenous or oral antibiotic in consultation with infectious diseases, with biofilm-active rifampicin added for staphylococci when the organism allows. Monitor CRP weekly at first; any clinical sign of recurrence prompts urgent aspiration. Follow-up. Clinical review at 2, 6 and 12 weeks with CRP, then at 3, 6 and 12 months with radiographs. Early mobilisation avoids the spacer-related complications (dislocation, fracture, prolonged immobilisation) seen in two-stage protocols. Complications
- Recognition
- Rising CRP, wound drainage, fever, pain within 3 months
- Prevention
- Strict selection, complete debridement, mandatory re-draping, correct antibiotic
- Management
- Urgent reoperation — usually convert to two-stage
- Recognition
- New pain and rising inflammatory markers months to years later
- Prevention
- Counsel the patient to present early with any new symptoms
- Management
- Aspirate, then manage by acuity — DAIR, one- or two-stage
- Recognition
- Radiographic loosening with normal inflammatory markers
- Prevention
- Sound cemented fixation; correct component and constraint choice
- Management
- Standard single-stage revision for an aseptic cause
- Recognition
- Persistent drainage, dehiscence, fluctuance
- Prevention
- Meticulous haemostasis and layered closure
- Management
- Negative-pressure therapy; rarely flap coverage
Viva & Exam Focus
SELECTSELECT — one-stage patient selection criteria
STEPSSTEPS — the one-stage operative sequence
DAIR retains the original implants and is indicated only for acute postoperative or haematogenous infection within 3-4 weeks of symptom onset. One-stage exchange is for chronic PJI (symptoms greater than 4 weeks) with a known organism and always involves complete explantation and reimplantation. DAIR leaves the implants in situ; one-stage never does.
Clinical Decision Scenarios
Practise clinical reasoning and management decisions out loud
“A 68-year-old man with a well-fixed cemented total hip arthroplasty presents with insidious groin pain 4 years after the index operation. CRP is 35 mg/L and ESR 45 mm/hr. Aspiration grows coagulase-negative Staphylococcus sensitive to vancomycin and rifampicin. There is no sinus tract, he is immunocompetent, and CT shows only minor osteolysis around the cup. Is he a candidate for one-stage revision, and what are the key technical steps you would emphasise?”
“You are planning a one-stage revision for an infected total knee arthroplasty. Preoperative aspiration grew methicillin-sensitive Staphylococcus aureus (MSSA). After radical debridement and explantation you notice that the medial collateral ligament has been compromised by the infectious process. How do you proceed?”
“A 72-year-old woman with an infected total hip arthroplasty has a sinus tract communicating with the joint. Aspiration grows a fully susceptible coagulase-negative Staphylococcus. She is otherwise fit and the bone stock is good. Why is one-stage revision contraindicated, and what is the correct management?”
Patient selection (Endo-Klinik pillars)
- Known susceptible organism on preoperative aspiration or biopsy — mandatory
- No sinus tract or fistulous communication — absolute contraindication
- Immunocompetent host with well-controlled comorbidities
- Healthy soft-tissue envelope without significant scarring or deficiency
- Adequate bone stock for immediate stable reimplantation
- Low-virulence organism (CoNS, streptococci, Cutibacterium) with biofilm-active options
Key technical steps
- Minimum five deep tissue samples before any antibiotic administration
- Radical debridement: complete synovectomy, membrane excision, removal of all foreign material, pulse lavage greater than 9 litres
- Complete explantation, confirming no retained cement or screws on fluoroscopy
- Mandatory re-draping: new drapes, re-scrub, new sterile field, entirely new instrument set
- Reimplantation with antibiotic-loaded cement (2-4 g per 40 g cement) tailored to the organism
- Verify stability, limb length and range of motion before final closure
Antibiotic strategy
- Local: antibiotic-loaded cement chosen by susceptibility (gentamicin, vancomycin, tobramycin)
- Systemic: 4-6 weeks targeted intravenous or oral under infectious-disease guidance
- Add biofilm-active rifampicin for staphylococci when the organism allows
- Weekly CRP initially; aspirate on any sign of recurrence
One-stage vs two-stage vs DAIR
- One-stage: known susceptible organism, no sinus, healthy host and tissues, good bone stock
- Two-stage: sinus tract, unknown or resistant organism, immunocompromised host, major bone loss or soft-tissue deficiency
- DAIR: acute postoperative or haematogenous PJI within 3-4 weeks — implants retained
- Reinfection in selected one-stage cases: 5-15 percent at 5 years, comparable to two-stage
Complications and failure
- Early reinfection (less than 3 months): usually technical — inadequate debridement, skipped re-draping, wrong antibiotic
- Late reinfection: new or haematogenous seeding — aspirate and manage by acuity
- Aseptic loosening: standard revision principles apply
- Wound complications: higher risk — may need negative-pressure therapy or flap coverage
Rehabilitation
- Protected weight-bearing from day 1, progressive to full by 6-12 weeks
- 4-6 weeks targeted antibiotic with weekly CRP monitoring
- Clinical and radiographic review at 2, 6 and 12 weeks, then 3, 6 and 12 months
- Early mobilisation avoids the spacer-related complications seen in two-stage protocols
Background & Evidence
Where one-stage fits. Periprosthetic joint infection is classified by timing and presentation, and management follows that pattern. Acute postoperative or acute haematogenous PJI (symptoms within about 3-4 weeks) is treated with DAIR and implant retention. Chronic PJI (symptoms greater than 4 weeks) requires exchange: either one-stage, in a strictly selected favourable case, or two-stage, for the complex case with a sinus tract, an unknown or resistant organism, an immunocompromised host, or major bone or soft-tissue loss. One-stage exchange is the middle path — for the chronic infection that is nonetheless straightforward enough to clear and reconstruct in a single sitting. The Endo-Klinik tradition. One-stage exchange has been performed at the Endo-Klinik in Hamburg since the 1980s, with published success rates supporting its use in selected patients. Modern series report reinfection rates of 5-15 percent at 5-10 years when strict selection criteria are applied — comparable to two-stage exchange in appropriately chosen cohorts. Advantages of one-stage include a single anaesthetic exposure, a shorter total hospital stay, lower cumulative cost, faster return to function, and avoidance of spacer-related complications (spacer dislocation, fracture, or prolonged immobilisation between stages). Limitations are the requirement for a known susceptible organism preoperatively, the technical demand of radical debridement in a single sitting, and the inability to confirm clearance of infection before reimplantation. These trade-offs are exactly why the selection pillars matter so much — the operation only succeeds when the organism, host and tissues are all favourable, and the re-draping protocol is honoured.
References
One-Stage Revision for Infected Total Hip Arthroplasty
- One-stage revision is a viable option for selected patients with infected total hip arthroplasty when the organism is known and susceptible.
One- and two-stage surgical revision of peri-prosthetic joint infection of the hip: a pooled individual participant data analysis of 44 cohort studies
- Pooled analysis of 44 cohort studies showing comparable reinfection rates between one-stage and two-stage revision for hip PJI in selected patients.
Re-infection outcomes following one- and two-stage surgical revision of infected knee prosthesis: a systematic review and meta-analysis
- Meta-analysis demonstrating that one-stage revision for infected knee prostheses has reinfection rates comparable to two-stage in appropriately selected cases.
One- and two-stage surgical revision of infected shoulder prostheses following arthroplasty surgery: a systematic review and meta-analysis
- Systematic review and meta-analysis providing evidence on outcomes of one-stage versus two-stage revision strategies across prosthetic joint infections.