Neurospine.
2023 Dec;20(4):1177-1185. 10.14245/ns.2346830.415.
Screw Insertional Torque Measurement in Spine Surgery: Correlation With Bone Mineral Density and Hounsfield Unit
- Affiliations
-
- 1Department of Neurosurgery, Chungbuk National University Hospital, Cheongju, Korea
- 2Department of Neurosurgery, St. Vincent’s Hospital, The Catholic University of Korea, Suwon, Korea
- 3Department of Neurosurgery, Eunpyeong St. Mary’s Hospital, The Catholic University of Korea, Seoul, Korea
- 4Department of Neurological Surgery, Duke University Medical Center, Durham, NC, USA
- KMID: 2549841
- DOI: http://doi.org/10.14245/ns.2346830.415
Abstract
Objective
Achieving successful fusion during spine surgery is dependent on rigid pedicle screw fixation. To assess fixation strength, the insertional torque can be measured during intraoperative screw fixation. This study aimed to explore the technical feasibility of measuring the insertional torque of a pedicle screw, while investigating its relationship with bone density.
Methods
Thoraco-lumbar screw fixation fusion surgery was performed on 53 patients (mean age, 65.5 ± 9.8 years). The insertional torque of 284 screws was measured at the point passing through the pedicle using a calibrated torque wrench, with a specially designed connector to the spine screw system. The Hounsfield units (HU) value was determined by assessing the trabecular portion of the index vertebral body on sagittal computed tomography images. We analyzed the relationship between the measured insertional torque and the following bone strength parameters: bone mineral density (BMD) and HU of the vertebral body.
Results
The mean insertion torque was 105.55 ± 58.08 N∙cm and T-score value (BMD) was -1.14 ± 1.49. Mean HU value was 136.37 ± 57.59. Screw insertion torque was positively correlated with BMD and HU in whole patients. However, in cases of osteopenia, all variables showed very weak correlations with insertional torque. In patients with osteoporosis, there was no statistically significant correlation between BMD and torque strength; HU showed a significant correlation.
Conclusion
The insertional torque of screw fixation significantly correlated with bone density (BMD and HU). HU measurements showed greater clinical significance than did BMD values in patients with osteoporosis.
- Full Text Links
-
- Actions
-
Cited
- CITED
-
- Close
- Share
-
- Similar articles
-
- A Biomechanical Study of Two Kinds of Tapered Pedicle Screws in Osteoporotic Lumber Spine
- Optimizing preoperative bone health assessment for adult spinal deformity: a prospective correlation analysis of intraoperative pedicle screw insertion torque and imaging modalities in Japan
- Significance of the Pars Interarticularis in the Cortical Bone Trajectory Screw Technique: An In Vivo Insertional Torque Study
- Clear Zone Formation around Screws in the Early Postoperative Stages after Posterior Lumbar Fusion Using the Cortical Bone Trajectory Technique
- Correlation between Bone Mineral Density Measured by Dual-Energy X-Ray Absorptiometry and Hounsfield Units Measured by Diagnostic CT in Lumbar Spine
