Radius fracture repair using volumetrically expanding polyurethane bone cement.

Area of Science:

• Orthopedic biomechanics
• Polymer science
• Skeletal repair

Background:

• Fragility fractures, particularly of the distal radius, necessitate robust repair techniques.
• Biomechanical justification is crucial for evaluating new fracture fixation methods.

Purpose of the Study:

• To investigate the biomechanical efficacy of an expanding polymer bone cement for fracture repair.
• To compare the strength of polyurethane bone cement against polymethylmethacrylate in human radius specimens.

Main Methods:

• Human radii (n=6 pairs) were osteotomized and repaired with either polyurethane or polymethylmethacrylate cement.
• Repaired specimens underwent biomechanical testing in cantilever beam (distal radius) and pure tension (proximal radius) configurations.
• Cement penetration into cancellous bone models and baseline mechanical properties were assessed.

Main Results:

• Polyurethane cement demonstrated 2.9 times higher shear stress and 2.5 times higher peak tensile bending stress resistance compared to polymethylmethacrylate.
• Polyurethane cement exhibited superior penetration into trabecular bone (49% farther).
• Mechanical properties of polyurethane cement met ASTM standards, showing high compressive and tensile strength.

Conclusions:

• Expanding polyurethane bone cement provides significant biomechanical advantages for fracture repair.
• This expanding cement represents a potential alternative strategy for treating fragility fractures.
• Further research is warranted to validate this technique for clinical application in distal radius fractures.