The Effect of Halo-Pelvic Traction on Bone Mineral Density of Vertebrae and Corresponding Risk Factors

Abstract

Objectives: Decreased bone mineral density (BMD) is associated with complications in implantation surgery for severe spinal deformity. In this quantitative study, we aimed to investigate the impact of halo-pelvic traction on vertebral bone mineral density (BMD) and identify the risk factors for a decrease in BMD.

Methods: Patients who underwent halo-pelvic traction at our hospital between 2019 and 2022 were included in the study. Patients' data, including height, weight, and BMD pre- and post-traction, were collected and analyzed. Quantitative computed tomography (QCT) was used to determine the BMD. The paired rank sum test was used to evaluate the changes in each measurement parameter. Linear regression was used to identify risk factors for a decrease in BMD.

Results: Fifteen patients were included in the study, nine women and six men, with an average age of 21.2 ± 7.3 years. Eleven patients had severe rigid scoliosis, while four had tuberculotic kyphosis. One expert measured the BMD values of 345 vertebrae using QCT. The average traction time was 143.3 ± 44.4 days. The average pre-traction BMD was 183.1 ± 73.8 mg/cm³ , and the average post-traction BMD was 140.5 ± 61.3 mg/cm³ (p < 0.01) Patients' height increased from an average of 151.3 ± 12.8 cm pre-traction to 165.5 ± 13.7 cm post-traction (p < 0.01), with traction length averaging 14.3 ± 6.2 cm (p < 0.01). The Cobb angle of the main curve declined from an average of 112.5° ± 24.4° pre-traction to 67.7° ± 19.8° post-traction (p < 0.01). Linear regression revealed a positive correlation between BMD loss and traction length and a negative correlation between BMD loss and correction rate.

Conclusions: Halo-pelvic traction can lead to a decrease in the BMD of the spinal vertebrae, with traction length positively correlated with BMD loss and correction rate negatively correlated with BMD loss. To prevent osteoporosis, physicians should ensure a limited traction length while utilizing better management techniques.

Keywords: Bone Mineral Density; Halo-Pelvic Traction; Qualitative Computed Tomography; Severe Spinal Deformity.