Biomechanical Comparison between Volar Plate Fixator and Nonbridge External Wrist Fixator

Area of Science:

• Orthopedic Surgery
• Biomechanical Engineering
• Trauma Care

Background:

• Intra-articular distal radius fractures present challenges for nonoperative management.
• Open Reduction and Internal Fixation (ORIF) involves implants that remain post-healing.
• External fixation offers stabilization without long-term implants.

Purpose of the Study:

• To compare the nonbridging fixator (NBX) with volar plate fixation (VPS) for 5-fragment, OTA 23 C3.2 distal radius fractures.
• To evaluate reduction quality, fixation rigidity, and range of motion (ROM).

Main Methods:

• A 5-part distal radius fracture model was created in 10 cadaver arms.
• Arms were randomly assigned to NBX or VPS fixation.
• Fluoroscopic imaging assessed ROM; axial loading determined failure strength.

Main Results:

• NBX demonstrated superior reduction in radial tilt (13.8° vs 6.3°) and volar tilt (26.3° vs 14.0°).
• NBX showed better restoration of radial length (3.4 mm vs 1.9 mm).
• NBX fixation had minimal effect on ROM, while VPS increased it post-fracture; NBX peak load was 925 N vs 2152 N for VPS.

Conclusions:

• The NBX provides adequate strength and superior alignment restoration compared to VPS for this fracture model.
• NBX offers a viable alternative to ORIF, minimizing long-term implant burden.
• NBX fixation preserves joint function with minimal ROM compromise.