背景:目前的研究缺乏对脊柱侧凸矫正过程中脊髓和神经根生物力学变化的全面研究。本研究采用有限元分析来广泛探索不同Cobb角度的这些生物力学变化,为临床治疗提供有价值的见解。
方法:个性化有限元模型,结合椎骨,韧带,脊髓,和神经根,是使用工程软件构建的。施加力和位移以实现Cobb角改善,指定T1/2-T4/5为上段,T5/6-T8/9为中间段,和T9/10-L1/2作为下段。牵引下的模拟,推,进行了牵引+扭转条件,并分析脊髓各节段和神经根的生物力学变化。
结果:在脊柱侧凸矫正过程中,在各种条件和移位下,中段脊髓始终存在受伤的风险。在牵引+扭转条件下,脊髓下段无明显损伤变化。在早期校正阶段,在所有情况下,上脊髓段都有受伤的风险,在推挤条件下,下脊髓段存在受伤的风险。牵引条件在中段和下段两侧都有神经损伤的风险。在推动条件下,所有节段的两侧都有神经损伤的风险。牵引+扭转条件涉及上段右神经损伤的风险,中间段的两边,和下段的左侧。在后期校正阶段,在牵引+扭转条件下,上脊髓段有受伤的风险,牵引条件下中段的左神经,在推动条件下,上段的右神经。
结论:当矫正率达到61-68%时,应特别注意中上脊髓。推送条件也需要注意下脊髓和主胸曲线两侧的神经根。牵引条件需要注意中段和下段两侧的神经根,虽然牵引结合扭转条件需要集中在上段的右侧神经根,中间段的两边,和下段的左侧神经根。
BACKGROUND: Current research lacks comprehensive investigation into the biomechanical changes in the spinal cord and nerve roots during scoliosis correction. This
study employs finite element analysis to extensively explore these biomechanical variations across different Cobb angles, providing valuable insights for clinical treatment.
METHODS: A personalized finite element model, incorporating vertebrae, ligaments, spinal cord, and nerve roots, was constructed using engineering software. Forces and displacements were applied to achieve Cobb angle improvements, designating T1/2-T4/5 as the upper segment, T5/6-T8/9 as the middle segment, and T9/10-L1/2 as the lower segment. Simulations under
traction, pushing, and
traction + torsion conditions were conducted, and biomechanical changes in each spinal cord segment and nerve roots were analyzed.
RESULTS: Throughout the scoliosis correction process, the middle spinal cord segment consistently exhibited a risk of injury under various conditions and displacements. The lower spinal cord segment showed no significant injury changes under
traction + torsion conditions. In the early correction phase, the upper spinal cord segment demonstrated a risk of injury under all conditions, and the lower spinal cord segment presented a risk of injury under pushing conditions.
Traction conditions posed a risk of nerve injury on both sides in the middle and lower segments. Under pushing conditions, there was a risk of nerve injury on both sides in all segments. Traction + torsion conditions implicated a risk of injury to the right nerves in the upper segment, both sides in the middle segment, and the left side in the lower segment. In the later correction stage, there was a risk of injury to the upper spinal cord segment under traction + torsion conditions, the left nerves in the middle segment under
traction conditions, and the right nerves in the upper segment under pushing conditions.
CONCLUSIONS: When the correction rate reaches 61-68%, particular attention should be given to the upper-mid spinal cord. Pushing conditions also warrant attention to the lower spinal cord and the nerve roots on both sides of the main thoracic curve. Traction conditions require attention to nerve roots bilaterally in the middle and lower segments, while traction combined with torsion conditions necessitate focus on the right-side nerve roots in the upper segment, both sides in the middle segment, and the left-side nerve roots in the lower segment.