A cross-sectional imaging study of young adults.
To investigate the prevalence of disc degeneration (DD) and displacement, anular tears, and Modic changes in lumbar magnetic resonance imaging (MRI) among young adults.
Although low back pain in young adulthood is common, the prevalence of spinal MRI findings at this age remains virtually unknown.
The study population was a subcohort of the Northern Finland Birth Cohort 1986. Subjects living within 100 km of Oulu (n = 874) were invited to participate in lumbar MRI at 20 to 22 years of age (mean: 21.2 years). Degree of DD, type of Modic changes, and presence of disc bulges, herniations, high intensity zone (HIZ) lesions, and radial tears at all lumbar levels were assessed.
Three hundred twenty-five women and 233 men (n = 558) attended the MR imaging. DD was significantly more frequent in men (54% vs. 42%, P = 0.005), as was multiple DD (21% vs. 14%, P = 0.036). The prevalences of disc bulges and radial tears were 25% and 9.1%, respectively, without gender differences. HIZ lesions were more common among women than men (8.6% vs. 4.3%, P = 0.046), whereas herniations were significantly more common among men (5.6% vs. 2.5%, P = 0.047). Only 2 disc extrusions were observed, one in each gender. All degenerative disc findings were more common at the L5–S1 level except HIZ lesions, which were most likely at L4–L5. The prevalence of the Modic changes was 1.4%, without gender difference, type I being more common than type II. Typically, Modic changes were located adjacent to a DD Grade 4 disc and at the 2 lowest levels.
Almost half of young Finnish adult aged 21 years had at least one degenerated disc, and a quarter had a bulging disc. Modic changes and disc herniations were, however, relatively rare.
We found disc degeneration and bulging to be common in the lumbar spine of 21-year-old Finnish man, whereas Modic changes and herniations were rare at this age. A significant gender difference was observed in prevalences of disc degeneration, herniations, and high intensity zone lesions.
From the *Department of Physical and Rehabilitation Medicine, Institute of Clinical Sciences, University of Oulu, Oulu, Finland; †Finnish Institute of Occupational Health, Oulu, Finland; ‡Institute of Diagnostics, University of Oulu, Oulu, Finland; §Department of Public Health, University of Helsinki, Helsinki, Finland; and ¶Institute of Health Sciences, University of Oulu, Finland.
Acknowledgment date: September 30, 2008. Acceptance date: January 19, 2009.
The manuscript submitted does not contain information about medical device(s)/drug(s).
No funds were received in support of this work. No benefits in any form have been or will be received from a commercial party related directly or indirectly to the subject of this manuscript.
Supported by the Academy of Finland grant (200868) (to J.K.).
Address correspondence and reprint requests to Jaro Karppinen, MD, PhD, Department of Physical and Rehabilitation Medicine, Institute of Clinical Sciences, University of Oulu, PL 5000, 90014 Oulu, Finland; E-mail: email@example.com