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Updated: Apr 23, 2026
10:09
Adjustable Stiffness, External Fixator for the Rat Femur Osteotomy and Segmental Bone Defect Models
Published on: October 9, 2014
22.1K
Accuracy of a hexapod parallel robot kinematics based external fixator
Maximilian Faschingbauer1, Hinrich J D Heuer1, Klaus Seide1,2
1Berufsgenossenschaftliches Unfallkrankenhaus (Trauma Hospital) Hamburg, Department for Trauma Surgery, Orthopaedics and Sportstraumatology, Hamburg, Germany.
Summary
This study precisely measured the accuracy of a motorized hexapod external fixator for bone deformities. The system demonstrated high accuracy in translations and rotations, proving reliable for clinical use.
Area of Science:
- Orthopedic biomechanics
- Medical device engineering
Background:
- Hexapod external fixators are vital for treating bone deformities and fractures.
- Comprehensive accuracy data is lacking for many hexapod fixator models.
Purpose of the Study:
- To evaluate the accuracy of a motorized Precision Hexapod® external fixator.
- To establish a reliable method for assessing hexapod fixator precision.
Main Methods:
- Utilized an infrared tracking system to monitor positioning maneuvers.
- Simulated radiographic projections by omitting one coordinate dimension.
- Calculated accuracy based on the difference between targeted and measured values.
Main Results:
- Median accuracy for translations was below 0.3 mm; for rotations, below 0.2°.
- Quartiles for translations ranged from -0.5 mm to 0.5 mm; for rotations, -1.0° to 0.9°.
- 149 positioning maneuvers were analyzed.
Conclusions:
- The experimental setup is precise and reliable for accuracy assessment.
- This methodology can be used to compare various hexapod fixators.
- The investigated hexapod system exhibits high accuracy.
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