• Konrad Bach, Jonathan Ford, Robert Foley, Jacob Januszewski, Ryan Murtagh, Summer Decker, and Juan S Uribe.
• Department of Neurological Surgery and Brain Repair, University of South Florida, Morsani College of Medicine, Tampa, Florida, USA. Electronic address: kbach@health.usf.edu.
• World Neurosurg. 2018 Dec 20.

BackgroundLittle published data exist regarding normal values of disc height. Current literature relies on plain radiographs making accurate measurements of individual lumbar disc height difficult.ObjectiveWe seek to establish normal values for lumbar intervertebral discs in different age groups using computed tomography scans in healthy individuals.MethodsTwo hundred forty anonymized abdominal computed tomography scans (131 women) were prospectively collected once institutional review board approval was obtained. Individuals with spinal pathologies were excluded. Disc height measurements were obtained at the anterior edge, center, and posterior edge of each vertebra in the midsagittal plane, averaged, and compared against age and sex.ResultsAverage age was 45 (14-83) years for women and 48 (14-89) years for men. Average lumbar disc height was 5.6 ± 1.1 mm for men and 4.8 ± 0.8 mm for women at T12/L1, 6.9 ± 1.3 mm for men and 5.8 ± 0.9 mm for women at L1/2, 8.1 ± 1.4 mm for men and 6.9 ± 1.1 mm for women at L2/3, 8.7 ± 1.5 mm for men and 7.6 ± 1.2 mm for women at L3/4, 9.2 ± 1.6 mm for men and 8.5 ± 1.6 mm for women at L4/5, and 8.8 ± 1.6 mm for men and 8.6 ± 1.8 mm for women at L5/S1. Disc height was significantly smaller for women than men (P < 0.001), except at L5/S1.ConclusionsVariation in disc height is determined much more by sex than age. The maximum height of the interbody space in the adult lumbar spine was at the L4/5 level (8.9 ± 1.7 mm [men], 8.6 ± 1.8 mm [women]). Based on our findings, >10 mm cage height will result in supraphysiologic interbody space restoration and potentially predispose to complications.Copyright © 2018 Elsevier Inc. All rights reserved.

6 keywords...

hide…