Related Experiment Video
Updated: May 10, 2026
08:46
Force System with Vertical V-Bends: A 3D In Vitro Assessment of Elastic and Rigid Rectangular Archwires
Published on: July 24, 2018
A biomechanical evaluation of three drop wire configurations
Johnattan Arango1, Daniel D Lewis, Caleb C Hudson
1Comparative Orthopaedics and Biomechanics Laboratory, University of Florida, Gainesville, Florida, USA.
Veterinary Surgery : VS
|June 26, 2013
Summary
Adding drop wires to single-ring external skeletal fixator constructs enhances stability in all loading directions. Positioning drop wires farther from the ring surface improves bending stiffness without compromising axial compression or torsional stability.
Area of Science:
- Orthopedics
- Biomechanical Engineering
- Biomaterials Science
Background:
- External skeletal fixators (ESFs) are crucial for bone fracture stabilization.
- Single-ring ESF constructs offer limited stability, especially under complex loading conditions.
- Enhancing the stiffness of ESF constructs is vital for optimal fracture healing and clinical outcomes.
Purpose of the Study:
- To evaluate the biomechanical effect of incorporating drop wires into single-ring external skeletal fixator constructs.
- To compare the construct stiffness of various drop wire configurations against a standard single-ring and a two-ring construct.
- To determine the influence of drop wire positioning on construct stability under different loading modalities.
Main Methods:
- A biomechanical study utilizing a Delrin bone model stabilized with single-ring external skeletal fixator constructs.
- Five construct configurations were tested: a base single-ring, three variations of drop wire placement (on fixation bolts, 1-hole posts, 2-hole posts), and a two-ring construct.
- Constructs were subjected to axial compression, craniocaudal bending, mediolateral bending, and torsion, with stiffness measured for each mode.
Main Results:
- Drop wire incorporation significantly increased the stiffness of single-ring constructs across all tested loading modes compared to the base construct.
- The two-ring construct demonstrated the highest stiffness in axial compression and torsion.
- Drop wire placement on 2-hole posts yielded the highest stiffness in mediolateral bending, surpassing even the two-ring construct in some instances.
Conclusions:
- Drop wires are an effective method for enhancing the stiffness of single-ring external skeletal fixator constructs.
- Optimizing drop wire placement, specifically positioning them farther from the ring surface using posts, significantly improves bending stiffness.
- This study provides valuable biomechanical data for the design and application of improved external skeletal fixation devices.
