Musculoskeletal model predicted paraspinal loading may quick estimate the effect of exercise on spine BMD

Shizhong Liu; Xiaoyu Xia; Yinxia Nie; Mengen Huang; Lin Meng; Juan Du

doi:10.3389/fbioe.2024.1464067

Musculoskeletal model predicted paraspinal loading may quick estimate the effect of exercise on spine BMD

Front Bioeng Biotechnol. 2024 Dec 23:12:1464067. doi: 10.3389/fbioe.2024.1464067. eCollection 2024.

Authors

Shizhong Liu^#^{1

2}, Xiaoyu Xia^#¹, Yinxia Nie³, Mengen Huang¹, Lin Meng¹, Juan Du¹

Affiliations

¹ Academy of Medical Engineering and Translational Medicine, Tianjin University, Tianjin, China.
² Rehabilitation Department, Tianjin Medical University General Hospital, Tianjin, China.
³ College of Sports Health, Tianjin University of Sport, Tianjin, China.

^# Contributed equally.

Abstract

Purpose: Spine is the most commonly found fracture site due to osteoporosis. Combined exercise including high-impact and resistance exercise shows the potential to improve bone mineral density (BMD) in the spine. However, the mechanical loading introduced by exercise, which is the mechanism of BMD changes, has not been investigated. The purpose of this study is to provide a new insight to investigate the mechanical stimuli of exercise induced bone remodelling.

Methods: Ten postmenopausal women with osteopenia who finalized a 6-month combined exercise of high-impact and resistance intervention were included. The changes in BMD were analyzed based on QCT images obtained from pre and post intervention. A modified full-body musculoskeletal model was built to estimate paravertebral muscle force (MF) and intervertebral compression force (ICF) during daily activities (walking and heel drop) and combined exercise including high-impact (jumping) and resistance exercise (pulling elastic bands).

Results: The paravertebral MF and ICF during jumping and pulling elastic bands exercise were all significantly greater than walking and heel drop exercise with up to 1.22-8.18 times. Spine BMD remained at the same level with no significant decline observed, especially at L1 (pre 247.95 ± 26.77 mg/cm³ and post 245.49 ± 22.04 mg/cm³). Comparing with daily activities, significant correlations were observed between the changes of BMD and the sum of spinal loadings generated by combined exercise at both global and segmental level (r = 0.687, p < 0.05).

Conclusion: It has been proved that paravertebral muscle forces and intervertebral compression forces generated by the combined exercise, rather than daily exercise, were the main reasons for the improvement of spine BMD. This study contributes into the understanding of exercise induced spine adaptation as well as a potential in fast prediction to evaluate the effect of physical exercise therapy.

Keywords: bone remodelling; exercise; musculoskeletal model; osteoporosis; spine biomechanics.

Grants and funding

The author(s) declare that financial support was received for the research, authorship, and/or publication of this article. This study was supported by the National Key Research and Development Program of China (2022YFF1202500, 2022YFF1202503), National Natural Science Foundation of China (12302420), Key Program of Tianjin Natural Science Foundation (23JCZDJC00830).