Methyl methacrylate concentrations in tissues adjacent to bone cement

Area of Science:

• Biomaterials Science
• Orthopedic Surgery
• Polymer Chemistry

Background:

• Bone cement, primarily poly(methyl methacrylate), is widely used in orthopedic procedures.
• Concerns exist regarding the potential toxicity of residual methyl methacrylate monomer leaching into surrounding bone tissue.
• Understanding monomer diffusion and degradation kinetics is crucial for patient safety.

Purpose of the Study:

• To quantify the concentration of methyl methacrylate monomer in bone tissue adjacent to polymerized bone cement in vivo.
• To determine the temporal profile of methyl methacrylate monomer presence in bone tissue post-implantation.

Main Methods:

• Poly(methyl methacrylate) bone cement was implanted into the distal femoral condyle of canine models.
• Bone tissue samples adjacent to the cement were collected at various time points after polymerization.
• Homogenization and liquid gas chromatography were employed to determine methyl methacrylate monomer levels.

Main Results:

• The highest methyl methacrylate monomer concentration (0.140%) was detected within 1000 micrometers of the bone cement immediately after polymerization.
• A similar concentration (0.137%) was observed 1 hour post-polymerization.
• Monomer levels dropped significantly, with no free methyl methacrylate monomer detected in adjacent bone tissue after 4 hours.

Conclusions:

• Methyl methacrylate monomer is present in bone tissue immediately following cement polymerization but dissipates rapidly.
• The rapid decrease suggests limited long-term exposure risk of free monomer to bone tissue.
• Further research could explore long-term effects and alternative bone cement formulations.