Effects of Low Bone Mineral Status on Biomechanical Characteristics in Idiopathic Scoliotic Spinal Deformity

World Neurosurg. 2018 Feb:110:e321-e329. doi: 10.1016/j.wneu.2017.10.177. Epub 2017 Nov 10.

Abstract

Background: Low bone mass in patients with adolescent idiopathic scoliosis has been well reported. Poor bone quality was regarded as a new and unique prognostic factor in aggravating curve progression. However, the potential biomechanical correlation between them remains unclear.

Methods: Three-dimensional finite element models of idiopathic scoliotic spine with different bone mineral status were created for axial loading simulation. An axial load of 3 different body weights was applied on different bone mineral mass models. The mechanical responses of the vertebral cortical and cancellous bone, facet joints, end plate, and intervertebral disc were analyzed.

Results: Accompanied with the low bone mineral status, thoracic scoliosis produced asymmetric and higher stress in the cortical bone, lumbar facet joints, and end plate at the concave side of the thoracic structure curve. Stress increased in the disc at the apex of the scoliosis, whereas it mildly decreased in the L4-5 and L5-S1 disc. Body weight gain increased the stress in scoliotic spine structures in all bone mineral statues.

Conclusions: Biomechanical simulations indicated that low bone mineral mass might aggravate curve progression and induce more serious lumbar compensatory scoliosis in patients with adolescent idiopathic scoliosis. Weight gain was also a risk factor for curve progression.

Keywords: Biomechanics; Bone quality; Finite element analysis; Idiopathic scoliosis.

MeSH terms

  • Adolescent
  • Biomechanical Phenomena
  • Body Weight
  • Bone Density*
  • Bone Diseases, Metabolic / complications
  • Bone Diseases, Metabolic / physiopathology*
  • Computer Simulation
  • Finite Element Analysis
  • Humans
  • Intervertebral Disc / physiopathology
  • Lumbar Vertebrae / physiopathology
  • Male
  • Models, Biological
  • Scoliosis / complications
  • Scoliosis / physiopathology*
  • Stress, Physiological
  • Thoracic Vertebrae / physiopathology