Clarifying the Effect of Cement Mixing Technique on Antibiotic Elution: Higher Porosity Increases, Not Decreases, Release

Arabi, Hamid; Akbarzadeh, Armin; Mortazavi, SM Javad

doi:10.22038/abjs.2026.96268.4317

Clarifying the Effect of Cement Mixing Technique on Antibiotic Elution: Higher Porosity Increases, Not Decreases, Release

Articles in Press

Document Type : LETTER TO THE EDITOR

Authors

Hamid Arabi ¹

Armin Akbarzadeh ²

SM Javad Mortazavi ³

¹ Orthopedic Research Center, Shahid Kamyab Hospital, Mashhad University of Medical Sciences, Mashhad, Iran

² Department of Orthopedic Surgery, Shiraz University of Medical Sciences, Shiraz, Iran

³ Tehran University of Medical Sciences Joint Reconstruction Research Center

10.22038/abjs.2026.96268.4317

Abstract

In their review on antibiotic-impregnated cement spacers, Shahpari et al. present an internally contradictory account of how cement mixing technique affects antibiotic elution. They correctly state that porosity increases elution and that hand mixing produces a more porous cement with intact antibiotic crystals, yet conclude that hand mixing decreases the overall elution rate. This conclusion conflates inconsistent elution with reduced elution. Inhomogeneous distribution in hand-mixed cement may produce non-uniform release kinetics, but the increased porosity raises the overall elution rate, whereas vacuum mixing lowers porosity and reduces release while improving mechanical strength. Multiple in vitro studies and systematic reviews confirm that hand mixing increases antibiotic elution relative to vacuum mixing. We propose a corrected statement and highlight the clinical relevance for surgeons selecting a mixing technique when preparing antibiotic-loaded spacers for two-stage revision arthroplasty.

Keywords

Polymethyl methacrylate

Anti-bacterial agents

Prosthesis-related infections

Arthroplasty, replacement, hip

Drug delivery systems

Subjects