Why is irrigation and debridement essential in suspected periprosthetic joint infection, and what does a two-stage revision involve?

• A. To reduce bone loss and improve imaging; two-stage revision involves immediate reimplantation with antibiotic cement.
• B. To reduce biofilm burden and bacterial load; two-stage revision involves removing the prosthesis, placing an antibiotic spacer, and reimplanting a new prosthesis after infection control.
• C. To facilitate wound healing; two-stage revision involves exchanging only the tibial component.
• D. To reduce pain; two-stage revision uses a spacer only for 2 weeks.

Answer: (B)

In suspected periprosthetic joint infection, the challenge is that bacteria form a protective biofilm on the implant, making them harder to eradicate with antibiotics alone. Irrigation and debridement target this problem by physically removing infected tissue and washing away contaminated material, which lowers the bacterial load and disrupts the biofilm, giving antibiotics a much better chance to work.

A two-stage revision follows a staged approach. In the first stage, the entire prosthesis is removed and a thorough debridement is performed to clear infected and dead tissue. An antibiotic-impregnated spacer is placed to deliver high local concentrations of antibiotics, help maintain joint space and alignment, and allow some degree of function. The patient then undergoes systemic antibiotic therapy while the infection is monitored. Once infection control is achieved—clinically and with laboratory markers—the second stage implants a new prosthesis. This two-stage strategy is favored for more difficult or chronic infections because it offers higher infection eradication rates and preserves bone and soft-tissue quality for a successful reimplantation.