Imaging Spinal Stenosis

Kiran S. Talekar, MD; Mougnyan Cox, MD; Elana Smith, MD; Adam E. Flanders, MD


Appl Radiol. 2017;46(1) 

In This Article

Abstract and Introduction


Degenerative lumbar spinal stenosis is a condition in which there is diminished space available for the neural and vascular elements in the lumbar spine secondary to degenerative changes in the spinal canal.[1] Classically, patients with spinal stenosis complain of lower-extremity pain exacerbated by walking and relieved by bending forward or sitting. Given that spinal stenosis is the most common reason for lumbar spine surgery in patients over 65 years,[2] and that many patients with anatomic narrowing are asymptomatic,[3] there is a recognized need for standardizing descriptive radiologic terms for spinal stenosis. The variability in description and reporting of spinal stenosis among radiologists and other physicians is well-documented.[4] This variability and lack of standardization may contribute to increased heterogeneity of the patient population undergoing surgery for spinal stenosis, rendering any analysis of surgical outcomes difficult at best. In response, a combined task force of radiologists and orthopedic surgeons endorsed a set of radiologic criteria for spinal stenosis in hope of improving communication among healthcare providers. Their recommendations for lumbar disc nomenclature were released in 2001 and revised in 2014.[5,6]

The diagnosis of spinal stenosis relies primarily on imaging to provide objective evidence of neurovascular compromise. The imaging features may be roughly classified into two categories; qualitative and quantitative findings. In 2011, Steurer and associates conducted a review of quantitative radiologic criteria published in the literature, and compiled a list of descriptive terms for lumbar spinal stenosis.[7] In 2012, Mamisch and associates surveyed an expert panel to learn which imaging criteria were considered most important for the diagnosis of spinal stenosis, and to assess the strength of agreement among experts. At the end of their survey, Mamisch et al concluded that while some qualitative criteria were considered important by imaging experts, there were no widely accepted quantitative criteria for the diagnosis of spinal stenosis.[8]

In this article, we will discuss pertinent anatomy, updated nomenclature, indications for imaging, and qualitative and quantitative criteria, illustrating our discussion of stenonis with examples for clarity where appropriate.