What is the role of antibiotic powder or impregnated cement, and what evidence supports its use in arthroplasty?

• A. Local prophylaxis; evidence mixed; mechanical concerns include cost and potential for resistant organisms; systemic prophylaxis remains essential.
• B. It is universally recommended with clear evidence of benefit; no downsides.
• C. It is never used due to high toxicity.
• D. It replaces systemic prophylaxis entirely.

Answer: (A)

Antibiotic powder or impregnated cement provide local prophylaxis by delivering high concentrations of antibiotics right at the prosthesis-bone interface where bacteria can seed and form biofilms. This approach aims to reduce infection risk after arthroplasty, and it can be helpful in cemented implants or in higher-risk patients. However, the evidence is mixed, with some studies showing a reduction in infection and others showing little or no additional benefit. There are practical concerns to weigh: added cost, the potential for promoting antibiotic resistance, and possible effects on the cement’s mechanical properties or fixation, depending on how the antibiotic is used. Because systemic prophylaxis around the time of surgery remains essential and provides broad protection, local antibiotic measures are an adjunct rather than a replacement.