Periprosthetic joint infectionDr. Jatinder S. Luthra

Prevalance - PJI

Increasing Total joint arthroplasty PJI – 2-2.4% ( Nation wide ) 1.6 billion dollar – 2020

0.6% - 0.9 % - PJI ( Single institute )

Clinical suspicion - PJI

Sinus tract Persistent wound drainage Acute onset – painful prosthesis H/o wound healing complications

Risk Factors - PJI

Patient Factors Age Obesity Diabetes Steroid Malignancy Rheumatoid arthritis

Risk Factors - PJI

Local Factors

Previous arthroplasty Arthroplasty for fractures Type of replaced joint Perioperative wound complications

Risk Factors - PJI

Operative Factors Operative time Dirty wounds No antibiotic cement No antibiotic prophylaxis

Pathogens - PJI

Gram Positive Bacteria Staphylococcus Streptococcus Enterococcus Diptheroids

Gram Negative Bacteria Pseudomonas

Pathogens - PJI

Anaerobes Mycobacteria Fungi Polymicrobial Culture negative

Antibiotic sensitivity - PJI

Classification - PJI

Acute post operative infection - PJI

Acute onset painful swelling Erythema and warmth Tenderness and discharge Sinus

Late Chronic Infection - PJI

Subtle signs and symptoms

Chronic pain and loosening

Progressive deterioration of function

Haematogenous seeding - PJI

Sudden onset pain

Trigger event – skin infection, dental extraction, respiratory / urinary infection

Immunosuppressed

Pathogenesis - PJI

Bacterial adhesion to biomaterial Cannot be eliminated without removing

biomaterial Resistance to antibiotics level 1000 times

higher Formation of biofilm

Biofilm - PJI

Serological investigation - PJI

White blood cell count

Usually normal in pt with implant infection

When elevated – infection is usually obvious

Serological investigation - PJI

ESR >30 – 82% sensitivity 85% specificity

CRP >10 – 96% sensitivity 92% specificity

Both elevated – 83 % probabilityBoth normal – Eliminate infection

Serological investigation – PJIInvestigational

Interleukin -6 Produced by monocyte and macrophagesReturns to normal 48 hrs post op

Procalcitonin

Serological investigation – PJIInvestigational

Plain X- rays - PJI

Non sensitive & specific

Polyethylene wearEndosteal scallopingRadiolucent lines Periosteal reaction Lacy periostitisOsteopenia

Ultrasound - PJI

Thickened capsule

Abscess

Aspiration of abscess

Radionuclide imaging - PJIBone scintigraphy

Technitium 99

Uptake - Rate of blood flow and Bone Formation

Diffuse uptake -Infection – osteolysis

Aeptic loosening – inflammation

Accuracy 50 – 70 %High negative predictive value

Radionuclide imaging – PJISequential Gallium scanning

Gallium 65 citrate

Bound to Transferrin

Complementary to scintigraphy

Uptake – inflammation

Accuracy – 70%- 80%

Radionuclide imaging – PJILabelled leucocyte scintigraphy

Indium 111 Labelling inflammatory

cells – neutrophils Increased periprosthetic

activity – infection Accumulates in infection Complimentary bone

marrow scan – Tc99m Accuracy 90%

Radionuclide imaging – PJIInvestigational agents

Technitium labelled Ciprofloxacin

Technitium labelled murine monoclonal antibody

Radionuclide imaging – PJIPET scan

Fluoro deoxy glucose

Increased metabolic activity – increased uptake

91% Sensitivity , 72 % Specificity

False positive – particle induced inflammation – aseptic loosening

MRI CT scan

Joint aspiration – PJIGram Stain & Culture

Strong suspicion infectionSensitivity – 57% - 93 %Specificity – 88% - 100 %

2 weeks after antibiotics Enriched culture – 14 days False positive - Contamination

Joint aspiration – PJILeucocyte count

Total count Differential count

> 500 /micro Liter Neutrophil – 64%

Joint aspiration – PJIInflammatory markers

Synovial fluid – CRP

Synovial leukocyte esterase

Intraoperative Gram stain – PJI

Sensitivity – 27 % - No Role

Intraoperative Tissue culture– PJI

Sensitivity – 94% Specificity 97% Not always positive 5-6 samples

Ultrasonification of prosthesis – disrupt glycocalyx

Intraoperative Frozen section– PJI

Preop – false elevation of ESR and CRP

Intra- op – joint looks non healthy

Sensitivity – 85% Specificity – 90%

> 5 PMN / high power field - Infection

Molecular Techniques - PJI

Polymerase chain reaction ( PCR ) – aspirateTarget gene – 16S RNAHigh False positive

Microarray and proteomic technologyTarget Specific bacterial genesProfile of genes ( microarray ) and proteins ( Proteomic )

Musculoskeletal infection society (MSIS) - PJI Criteria

Sinus Tract Isolated pathogen – 2 separate tissue culture /Specimen

Four of following criteria 1. ESR2. CRP3. Synovial white cell count4. Synovial PMN %5. > 5 neutrophil/ High power field- 5 field

Treatment options - PJI

Surgical- Debridement and retention prosthesis- Resection arthroplasty with reimplantation- Definitive resection arthroplasty with/without

arthrodesis- Amputation

Non Surgical - Suppressive antimicrobial therapy

Surgical Treatment – PJI Debridement and retention of prosthesis

Prodedure Debridement Exchange of modular componentsProlonged antibiotic therapy

IndicationDuration of symptoms < 3 weeksJoint age < 30 days

Success Rate – 85 %

Medical Treatment – PJI Debridement and retention of prosthesis

Staph PJI

2-6 wks – I.V. PSA + Rifampicin ( 300 mg BID )

Rifampicin + Companion drug ( Cipro /Levo ) – THA – 3 months TKA – 6 months

Non Staph PJI

4 – 6 wks of I.V. / Oral -PSA

Surgical Treatment – PJITwo-stage replacement arthroplasty

Prodedure

Removal of prosthesis

Surgical debridement of joint

Administration of antimicrobial with delayed implantation

Antibiotics – 4 – 6 weeks

Surgical Treatment – PJITwo-stage replacement arthroplasty

PrerequisitesAdequate bone stock

Medical fitness for multiple surgeries

Normal serology / negative aspiration

Stop antibiotics for 2 weeks

Surgical Treatment – PJITwo-stage replacement arthroplasty

Time intervalEarly repimplantation – less success2 weeks – 35%6 weeks – 70 – 90 % Intraop. – Frozen sectionCulture and histopath evaluation

Surgical Treatment – PJITwo-stage replacement arthroplasty

Antibiotics spacerDynamic spacer Joint mobilityEase of revision

Static spacerHigher dose of antibioticFavourable environment for wound healing

Medical Treatment – PJITwo-stage replacement arthroplasty

4-6 weeks of i.v./ Bioavailable oral PSAMore virulent Staph aureusCefazolin / NaficillinMRSA – Vancomycin Rifampicin – no role

Surgical Treatment – PJIOne-stage replacement arthroplasty

Procedure

Prosthesis , Infected bone , soft tissue excised – RADICAL debridement

New prosthesis implanted same surgery

Iv antibiotics

Surgical Treatment – PJIOne-stage replacement arthroplasty

AdvantagesSingle procedureLower costEarlier mobilityPatient convenience

Disadvantage ReinfectionResidual microorganism

Organism identified – good sensitivity

Overall success rate – 75% - 100%

Medical Treatment – PJIOne-stage replacement arthroplasty

Staph. PJI

2- 6 weeks PSA + RifampicinRifampicin + Companion Drug – 3 months

Non Staph PJI

4- 6 weeks I.V/ Oral PSA

Surgical Treatment – PJIResection Arthroplasty

ProcedureDefinitive prosthesis removalNo subsequent implantation

DisadvantageShortened limbPoor functionPatient dissatisfaction

Surgical Treatment – PJIResection Arthroplasty

IndicationsPoor quality bone and soft tissueRecurrent infectionMDR organismFailure of previous exchange procedure

Outcome Hip – 60% - 100%Knee 50%- 89%

Surgical Treatment – PJIArthrodesis

Bony ankylosis of joint

Subsequent reimplantation not feasiblePoor bone stockRecurrent infectionLoss extensor mech.

Overall success – 70% - 90%

Surgical Treatment – PJIAmputation

A/K amputation

All other option exhausted

Severe pain, soft tissue compromise, extensive bone loss , vascular compromise

Non - Surgical Treatment – PJI

Suppressive antimicrobial therapy

Frail Elderly Sick patient

Symptomatic relief Prevent systemic spread rather than

eradication of infection

Success rate – 10% - 25%

Summary

Thank You