Clinical Rationale Axial Load

Dynamic Effects on the Lumbar Spinal Canal: Axially Loaded CT-Myelography and MRI in Patients with Sciatica an/or Neurogenic Claudication, Jan Willén, M.D., Ph.D.; Barbro Danielson, M.D., Ph.D.; Arne Gaultiz, M.D.; Thomas Niklason; Nils Schönström, M.D., Ph.D.; Tommy Hansson, M.D., Ph.D. SPINE 1997, Volume 22, Number 24, pp 2968-76.

• 79% of patients experienced a significant reduction of the dural sac cross-sectional area during axial compression;
• 35% of patients passed the borderlines for relative (100mm²) or absolute stenosis (75mm²);
• 36% of patients experienced deformation of the dural sac during axial compression;
• 13% of patients experienced a narrowing of the lateral recess during axial compression.

This study recommends axial loading of the lumbar spine in computed tomographic scanning and magnetic resonance imaging and concludes that the diagnostic specificity of spinal stenosis will increase considerably when a patient is subject to axial load.