Is restoration of vertebral body height after vertebral body fractures and minimally-invasive dorsal stabilization with polyaxial pedicle screws just an illusion?

Arch Orthop Trauma Surg. 2024 Jan;144(1):239-250. doi: 10.1007/s00402-023-05082-8. Epub 2023 Oct 15.

Abstract

Introduction: Thoracolumbar spine fractures often require surgical treatment as they are associated with spinal instability. Optimal operative techniques and treatment are discussed controversially. Aim of our prospective cohort study was to investigate the sagittal alignment after reduction, the secondary loss of reduction and the subjective outcome as well as the causal correlation of these parameters after minimally invasive stabilization of thoracic and lumbar fractures with polyaxial pedicle screws.

Materials and methods: In a single-center study, a total of 78 patients with an average age of 61 ± 17 years who suffered a fracture of the thoracic or lumbar spine were included and subjected to a clinical and radiological follow-up examination after 8.5 ± 8 months. The kyphotic deformity was measured by determining the vertebral body angle, the mono- and bi-segmental wedge angle at three time points. The patients' subjective outcome was evaluated by the VAS spine score.

Results: After surgical therapy, a significant reduction of the traumatic kyphotic deformity was shown with an improvement of all angles (vertebral body angle: 3.2° ± 4.4°, mono- and bi-segmental wedge angle: 3.1° ± 5.6°, 2.0° ± 6.3°). After follow-up, a significant loss of sagittal alignment was observed for all measured parameters with a loss of correction. However, no correlation between the loss of reduction and the subjective outcome regarding the VAS spine scale could be detected.

Conclusion: The minimally invasive dorsal stabilization of thoracic and lumbar spine fractures with polyaxial pedicle screws achieved a satisfactory reduction of the fracture-induced kyphotic deformity immediately postoperatively with a floss of reduction in the further course. However, maybe the main goal of this surgical procedure should be the prevention of a complete collapse of the vertebral body instead of a long-lasting restoration of anatomic sagittal alignment.

Level of evidence: II.

Keywords: Kyphotic deformity; Minimal invasive posterior stabilization; Polyaxial pedicle screws; Sagittal alignment; Thoracolumbar fractures.

MeSH terms

  • Adult
  • Aged
  • Fracture Fixation, Internal / methods
  • Fractures, Bone* / complications
  • Humans
  • Illusions*
  • Kyphosis* / etiology
  • Kyphosis* / surgery
  • Lumbar Vertebrae / injuries
  • Lumbar Vertebrae / surgery
  • Middle Aged
  • Pedicle Screws* / adverse effects
  • Prospective Studies
  • Retrospective Studies
  • Spinal Fractures* / complications
  • Spinal Fractures* / diagnostic imaging
  • Spinal Fractures* / surgery
  • Thoracic Vertebrae / injuries
  • Thoracic Vertebrae / surgery
  • Treatment Outcome
  • Vertebral Body