Related Experiment Video
Updated: Apr 26, 2026
09:41
Calibrated Forceps Model of Spinal Cord Compression Injury
Published on: April 24, 2015
20.5K
Forces in spinal cannulation and breaches ex vivo
Aubrey Blair-Pattison1, Richard W Hu2, Ganesh Swamy2
1Biomedical Engineering, University of Calgary, Calgary, AB, Canada McCaig Institute for Bone and Joint Health, University of Calgary, Calgary, AB, Canada.
Summary
Surgeons experienced lower forces during pedicle screw tract cannulation than during breaches. Understanding these forces is crucial for safe spinal stabilization procedures.
Area of Science:
- Spinal surgery
- Biomechanics
- Orthopedic research
Background:
- Pedicle screw insertion is vital for spinal stabilization and correction.
- Accurate trajectory during pedicle cannulation prevents cortical wall breaches.
- The forces and torques during pedicle probing are not well understood.
Purpose of the Study:
- To quantify the forces and torques during pedicle tract cannulation.
- To differentiate forces between correct and incorrect cannulation paths.
Main Methods:
- Two experienced surgeons used a modified probe with a load cell.
- Cadaveric specimens (T12-S1) were used for testing (n=76 pedicles).
- Forces and torques were measured during cannulation and cortical breach.
Main Results:
- Average cannulation axial force was 48 N (SD=13 N).
- Medial breach force averaged 129 N (SD=25 N), lateral breach 86 N (SD=27 N).
- Cannulation forces were significantly lower than breach forces across all degrees of freedom (p < 0.001).
Conclusions:
- Significant variations in forces and torques were observed, reflecting clinical bone quality differences.
- This study provides the first reported measurements of absolute and relative pedicle probe forces and torques.
