Asymmetrical vertebral collapse from spinal metastasis in lower thoracic and lumbar spine

J Orthop Sci. 2017 May;22(3):405-410. doi: 10.1016/j.jos.2016.12.013. Epub 2017 Jan 9.

Abstract

Objective: The purpose of this study was to investigate the differences between spinal metastasis and osteoporotic compression fractures on plain X-ray images, focusing on asymmetrical vertebral collapse and fracture level.

Materials and methods: This study included 180 patients with pathological collapse from spinal metastasis (188 vertebrae) who were treated at our institution and 70 patients (92 vertebrae) with osteoporotic compression fractures. Anteroposterior X-ray images of the lower thoracic and lumbar spine were evaluated for asymmetrical collapse deformity.

Results: Asymmetrical collapse was found in 134 vertebrae (71.3%) with metastasis, and in 20 osteoporotic vertebrae (21.7%); this difference was significant (p < 0.0001). The asymmetrical collapse angle in spinal metastasis patients ranged from 0 to 18°, with a mean of 7.0 and a standard deviation (SD) of 4.5. In contrast, the asymmetrical collapse angle in patients with osteoporotic fractures ranged from 0 to 13°, with a mean of 3.1 and a SD of 2.8. The difference in collapse angle between the two groups was statistically significant (p < 0.001). The cutoff value to suspect spinal metastasis was determined to be 5° or more (sensitivity 0.67, specificity 0.74). Fracture at Th10 or below L3 was found in 20.2% of spinal metastasis patients; only 3% of osteoporotic fractures occurred at these levels.

Conclusion: Asymmetrical collapse with an angle of 5° or more and fractures at atypical levels on plain radiographs can be useful clues to spinal metastasis.

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Female
  • Follow-Up Studies
  • Fractures, Compression / diagnosis
  • Fractures, Compression / etiology*
  • Fractures, Compression / surgery
  • Fractures, Spontaneous / diagnosis
  • Fractures, Spontaneous / etiology*
  • Fractures, Spontaneous / surgery
  • Humans
  • Lumbar Vertebrae*
  • Magnetic Resonance Imaging
  • Male
  • Middle Aged
  • Neoplasm Metastasis
  • Positron-Emission Tomography
  • Prognosis
  • Retrospective Studies
  • Spinal Fractures / diagnosis
  • Spinal Fractures / etiology*
  • Spinal Fractures / surgery
  • Spinal Neoplasms / complications*
  • Spinal Neoplasms / secondary
  • Spinal Neoplasms / surgery
  • Thoracic Vertebrae*
  • Time Factors
  • Tomography, X-Ray Computed
  • Vertebroplasty / methods*