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Amphotericin B delivery from bone cement increases with porosity but strength decreases

Chris Kweon1, Alex C McLaren, Christine Leon

  • 1Banner Orthopaedic Residency, 901 E Wiletta, Phoenix, AZ 85006, USA.

Clinical Orthopaedics and Related Research
|June 4, 2011
PubMed
Abstract

Insights

Adding poragen to amphotericin B-loaded bone cement increases antifungal release but significantly reduces compressive strength. This limits its use for implant fixation due to compromised mechanical integrity.

Area of Science:

  • Orthopaedic Surgery
  • Biomaterials Science
  • Pharmacology

Background:

  • Amphotericin B, a hydrophobic antifungal, is used for orthopaedic infections.
  • Debate exists regarding amphotericin B release from polymethylmethacrylate (PMMA).
  • The impact of poragen on amphotericin B release and PMMA compressive strength is unclear.

Purpose of the Study:

  • To quantify amphotericin B release from PMMA bone cement.
  • To assess the effect of poragen on drug release and cement compressive strength.
  • To determine the viability of poragen-enhanced antifungal delivery in bone cement.

Main Methods:

  • Formulation of antifungal-loaded bone cement (ALBC) with amphotericin B and cefazolin (poragen).
  • Elution of standardized test cylinders in deionized water.
  • Measurement of cumulative amphotericin B release and compressive strength over time.
  • Statistical analysis using repeated-measures analysis of variance.

Main Results:

  • ALBC with poragen demonstrated significantly higher amphotericin B release (12.76 μg/cylinder) by Day 15 compared to ALBC without poragen (1.74 μg/cylinder).
  • Amphotericin B alone did not alter compressive strength.
  • Adding poragen markedly decreased compressive strength, with further reduction observed during elution (80 MPa to 46 MPa over 30 days).

Conclusions:

  • Amphotericin B release from ALBC is minimal without poragen.
  • High-dose poragen enhances amphotericin B release but compromises cement compressive strength.
  • The significant decrease in mechanical integrity limits the clinical application of poragen-modified ALBC for implant fixation.

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