Arthroscopic washout of septic arthritis

Why are we operating?

Pus in a joint is an emergency for cartilage: the scope washes the knee with litres while the cultures are still growing.

Indication: Septic arthritis of the native knee, on aspiration findings and clinical picture; prosthetic joints follow different rules.

The operation in 4 steps

1. 01Confirming and culturing

   The joint is aspirated before antibiotics when possible: cell count, Gram stain, crystals, culture.

2. 02Portals and inspection

   Standard arthroscopy portals; the joint is inspected compartment by compartment and synovitis graded.

3. 03Lavage and debridement

   Six to nine litres of saline through the joint; fibrin and infected synovium debrided with a shaver as needed.

4. 04Drains, antibiotics, reassessment

   The joint may be drained, antibiotics run long guided by cultures, and re-washout booked on response rather than by routine.

Anatomy you need

Femur, tibia and patella around the joint space the arthroscope enters through its two portals.

What can go wrong

• Intra-abdominal abscess

  Swinging fevers, malaise, and localized pain from day 5 onward, classically after perforated appendicitis.

• Surgical-site infection

  Wound erythema, warmth, discharge, and pain out of proportion, typically from postoperative day 4–7.