Is lumbar stenosis associated with thoracic stenosis? A study of 1,072 human cadaveric specimens

Background contextTandem stenosis of the cervical and lumbar spine is known to occur in 5% to 25% of individuals with symptomatic neural compression in one region. However, the prevalence of concurrent lumbar and thoracic stenosis is not known. Whether this relationship is because of an increased risk of degenerative diseases in these individuals or because of the tandem presence of stenosis in lumbar and thoracic canal is unknown.PurposeTo determine the prevalence of concurrent lumbar and thoracic stenosis, and whether the presence of stenosis in the lumbar spine is associated with stenosis in the thoracic spine.Study designA morphoanatomic study of lumbar and thoracic cadaveric spines.MethodsOne thousand seventy-two adult skeletal specimens from the Hamann-Todd Collection in the Cleveland Museum of Natural History were selected. Canal area at each level was also calculated using a geometric formula. A standard distribution for each level was created, and values that were 2 standard deviations below mean were considered as being stenotic. Linear regression analysis was used to determine the association between the additive canal areas at all levels in the lumbar and thoracic spine and between the number of stenotic lumbar and thoracic levels. Logistic regression was used to calculate the odds ratios (OR) for concurrent lumbar and thoracic stenosis.ResultsThe prevalence of concurrent lumbar and thoracic stenosis is 1.42%. A positive association was found between the additive areas of all lumbar and thoracic levels (p<.01). No association, however, was found between the number of stenotic lumbar and thoracic levels (p=.7). Log regression demonstrated no significant association (OR <1) between stenosis in the lumbar and thoracic spine.ConclusionsThe stenosis of the lumbar spine is not associated with the thoracic stenosis. Thus, stenosis in lumbar and thoracic levels does not seem to be contributed by tandem stenosis.