Thermomechanical method for cement extraction in revision arthroplasty

Area of Science:

• Orthopedic Surgery
• Biomaterials Science
• Materials Engineering

Background:

• Bone cement extraction during joint revision surgery presents significant challenges.
• Current methods for bone cement removal are often unsatisfactory.
• Understanding the thermomechanical properties of bone cement is crucial for improving extraction techniques.

Purpose of the Study:

• To investigate the impact of heat on the mechanical properties and microstructure of bone cement.
• To determine the glass transition temperature (T_G) of bone cement.
• To establish a thermomechanical method for easier bone cement extraction.

Main Methods:

• Thermoanalysis of polymerized bone cement samples using differential thermal analysis and thermogravimetry.
• Heating samples to 390°C at a rate of 5 K/min.
• Analysis of microstructural changes using 3D micro-X-ray computed tomography (3D-μXCT).

Main Results:

• Bone cement transitions from a firm elastic state to a plastic viscosity state between 60°C and 155°C in air.
• Decomposition of the molten bone cement occurs between 290°C and 390°C.
• The glass transition temperature (T_G) was determined to be approximately 60°C (air) and 65°C (nitrogen).

Conclusions:

• The glass transition temperature of bone cement was successfully determined.
• Heating bone cement to at least 65°C can reduce the required removal strength by over 50%.
• A thermomechanical approach utilizing elevated temperatures offers a promising solution for efficient bone cement extraction.