Courtesy: Dr S Macdonald, Ashok Shyam TV, Ortho

Why This Matters

Incidence of infection after TKA: ~1% to 2.5%.
Devastating complication:
- Severe patient morbidity.
- Surgeon burden.
- High healthcare cost.
Prevention requires a multifactorial strategy:
- Patient factors
- Intraoperative factors
- Postoperative factors

1 Patient-Related Risk Factors

Some modifiable, some not.

Gender

Large registry data (e.g., Finnish arthroplasty registry ~43,000 TKAs):
- Slightly higher infection in males (~1%) vs females (~0.7%).
Not clinically modifiable.

Diagnosis

Osteoarthritis: ~0.7% infection risk.
Rheumatoid arthritis: approximately double the risk.

Management in Rheumatoid Arthritis

NSAIDs

Stop ~7–10 days preoperatively.

Steroids

Perioperative stress dosing recommended.
Common protocol: 3 doses of 25 mg IV steroid.

Methotrexate

Historically stopped.
Recent data suggests continuation may not increase infection risk.
Practice varies.

Leflunomide

Should be stopped (increased infection risk).

TNF-alpha blockers

Evidence suggests may not significantly increase infection risk.
Coordinate with rheumatologist.

Practical strategy:

Collaborate with rheumatology.
Temporarily hold immunosuppressive drugs where safe.

Diabetes

Poor glycemic control – higher infection risk.
Elevated HbA1c strongly associated with increased infection.

Recommendation:

Screen preoperatively.
Optimize glucose control before surgery.

Obesity

Associated with:
- Prolonged wound drainage.
- Higher superficial complications.
Deep infection risk likely increased.
BMI trends:
- Obesity prevalence rising globally.
- Increasing number of patients with BMI >40.

Reality:

Weight loss before surgery is difficult.
Counseling important but limited impact in practice.

2 Intraoperative Factors

These are largely under surgeon control.

Antibiotic Prophylaxis

Standard of care.
First-line: Cefazolin (if no allergy).
Adjust for MRSA risk or allergies.

Operating Room Environment

Air Quality

High air exchange turnover essential.
Laminar flow beneficial but not universally available.
UV light rarely used routinely.

OR Traffic

Increased traffic – higher contamination.
Minimize personnel and door openings.

Sterile Technique

Change gloves before handling implants.
Avoid breaks in sterility.
Maintain discipline in the OR.

Surgical Time

Longer operative time – increased infection risk.
Efficient, well-planned surgery reduces risk.

Antibiotic Cement

Controversial but strongly supported by registry data.

Large registry findings (Norwegian, Finnish, etc.):

IV antibiotics alone:
- ~1% infection rate.
IV + antibiotic-loaded cement:
- Reduced to ~0.6–0.7%.

Findings:

Lower septic and aseptic loosening rates.
Gentamicin-containing cement performs best.
No strong evidence of increased resistant organisms.

Takeaway:

Antibiotic cement significantly reduces infection risk.
Especially useful in primary TKA.

3 Postoperative Factors

Drain Use

No convincing evidence either way.
Surgeon preference.

DVT Prophylaxis

Necessary.
Avoid starting anticoagulation preoperatively.

Wound Complications

Critical point:

Hematoma
Persistent drainage
Skin necrosis
Superficial infection

These do NOT resolve spontaneously.

They must be:

Identified early.
Managed aggressively.

Failure to intervene early -deep periprosthetic infection.

Dental Prophylaxis

Controversial topic.
No strong evidence for routine long-term prophylaxis.
Follow updated guidelines.

Key Infection Prevention Principles

Optimize the patient.
Use perioperative IV antibiotics.
Consider routine antibiotic cement.
Minimize OR traffic.
Maintain strict sterile discipline.
Keep operative time efficient.
Aggressively manage wound issues.

Final Message

Infection prevention in TKA is not one intervention—it is a layered defense strategy:

Patient optimization
Intraoperative discipline
Postoperative vigilance

No single step eliminates infection risk.

A multifaceted, systematic approach offers the best protection.

Post Views: 149