Archives of Orthopaedic and Trauma Surgery - 2026-04-06 - Journal Article
Biomechanical comparison of palmar plate plus headless compression screw versus radiopalmar double plating in AO/OTA 23-C2.1 distal radius fractures.
Riegner P, Spiegel C, Kohler FC, Kielstein H, Zderic I, Gueorguiev-Rüegg B, Lenz M, Weschenfelder W
Topics
Key Takeaway
Palmar plate plus headless compression screw fixation of AO/OTA 23-C2.1 distal radius fractures produces significantly greater initial radial-shaft rotation (1.14° vs. 0.51°, p=0.02) and progressive ulnar-shaft rotation after cyclic loading compared to radiopalmar double plating, despite equivalent axial stiffness.
Summary Depth
Choose how much analysis to show on this article page.
Summary
This cadaveric biomechanical study compared palmar plate plus HCS versus radiopalmar double plating for standardized AO/OTA 23-C2.1 distal radius fractures with metaphyseal defect zones in 11 matched pairs subjected to 5000 cycles of axial loading at 150 N. Both constructs showed equivalent stiffness and axial displacement with no hardware failure. The plate-HCS construct demonstrated significantly greater initial radial-shaft rotation (1.14° vs. 0.51°, p=0.02) and a significant increase in ulnar-shaft rotation after cyclic loading (0.97° to 1.16°, p=0.02) not seen in the double-plate group.
Key Limitation
The small final sample size of 9 pairs after exclusions substantially limits statistical power, and the 150 N cyclic load may not replicate physiologic torsional and bending forces encountered during early wrist mobilization.
Original Abstract
INTRODUCTION
This biomechanical study compared the fracture stability of a palmar plate combined with a headless compression screw (HCS) with that of a radiopalmar double-plate construct for AO/OTA 23-C2.1 distal radius fractures with metaphyseal defect zones.
MATERIALS AND METHODS
Eleven matched pairs of cryopreserved human radii were prepared with standardized AO/OTA 23-C2.1 fractures. Left radii (n = 11) were fixed with a palmar plate plus HCS, while right radii (n = 11) received a radiopalmar double-plate construct. Construct stiffness and axial displacement were assessed using a universal testing machine. Interfragmentary range of motion (ROM) and rotation (ROT) were quantified using an optical three-dimensional motion-tracking system. Measurements were obtained before and after 5000 cycles of dynamic axial loading at 150 N. Two specimen pairs were excluded due to early failure or incomplete data acquisition.
RESULTS
Both constructs demonstrated comparable stiffness and axial displacement, with no implant loosening or hardware failure observed. Interfragmentary ROM did not differ significantly between groups. However, the plate–HCS construct showed greater variability in rotational parameters. Initial radial-shaft rotation was significantly greater in the plate–HCS group (1.14° vs. 0.51°, p = 0.02). After cyclic loading, ulnar-shaft rotation increased significantly in the plate–HCS group (0.97° to 1.16°, p = 0.02) but not in the double-plate group.
CONCLUSION
In this cadaveric model, fixation with a palmar plate combined with an HCS provided comparable axial stability but demonstrated greater variability and less consistent rotational control compared with radiopalmar double plating. Clinical studies are required to determine whether this less invasive construct achieves equivalent outcomes in vivo.