Investigation of physiological stress shielding within lumbar spinal tissue as a contributor to unilateral low back pain: A finite element study.

摘要: Abstract Introduction The pathomechanism of low back pain (LBP) remains unknown. Unilateral LBP patients have demonstrated ipsilateral morphological and material property changes within the lumbar soft tissues, potentially leading to asymmetric tissue loading. Through comparison healthy unilateral validated finite element models (FEMs), this study investigates potential stress shielding consequential spinal augmentation. Methods Two FEMs musculoskeletal system – one demonstrating conditions were developed undergoing 30-degree flexion. included vertebrae, intervertebral discs, tissues from L1-S1. Material properties selected for retrieved published literature. To reflect LBP, paraspinal morphology was atrophied, while moduli increased. symptomatic thoracolumbar fascia (TLF) uniformly Validation preceded testing. Results Model validation in flexion accomplished through Compared model, multifidus (MF), longissimus thoracis (LT), TLF exhibited average tension +7.9, -5.1, +9.3%, respectively. Likewise, MF, LT, +19.0, -10.4, +16.1% respectively, whereas asymptomatic -4.0, -2.0, +0.4% tension, Conclusion Relative a 19.5 kPa increase stress, with 99.8% distributed towards TLF, suggesting load allocation bias tissues. Consequentially, muscles may be unable withstand loading, shielding.