Different osteosyntheses for Colles' fracture: a mechanical study in 42 cadaver bones

Area of Science:

• Orthopedic biomechanics
• Surgical implant technology

Background:

• Numerous internal fixation plate designs for distal radius fractures exist.
• Limited biomechanical comparisons of these novel implants have been conducted.

Purpose of the Study:

• To compare the mechanical properties of five distinct commercial plates (three volar, two dorsal) against standard K-wire fixation.
• Utilize a distal radial cadaver model for biomechanical assessment.

Main Methods:

• 42 human radial bones were analyzed, with bone mineral density (BMD) measured via DEXA.
• Bones were allocated into six equivalent groups based on BMD and mineral content.
• A distal radial osteotomy was performed, removing a dorsal 30-degree wedge of bone.
• Rigidity, yield load, and maximum load were evaluated for K-wire fixation and five plate groups.

Main Results:

• No significant differences in stiffness, yield load, or maximum load were found when pooling volar and dorsal plate data.
• K-wire fixation demonstrated significantly lower yield load compared to three plate groups.
• All five plate groups showed no statistically significant differences in yield load among themselves.
• K-wire fixation exhibited lower rigidity than all plate groups.
• K-wire fixation and one plate group had a statistically significant lower maximum load than four other plate groups.

Conclusions:

• Volar plates provide equivalent mechanical stability to dorsal plates, serving as a viable alternative.
• K-wire osteosynthesis is biomechanically inferior to plate osteosynthesis for distal radius fractures.