The occurrence of anular tears and their relation to lifetime back pain history: a cadaveric study using barium sulfate discography.
METHODS
The occurrence of anular tears and general disc degeneration of the lumbar spine was studied in relation to the lifetime frequency of back pain.


BACKGROUND
Although anular tears and ruptures are common targets for diagnostic and therapeutic approaches, the relationship between disc findings and back pain has been weak or nonexistent.


METHODS
The data comprised barium sulfate discograms of lumbar spine levels from 157 male cadavers. The extent of "anular tears" and "general disc degeneration" based on posterior-anterior and side views were evaluated separately using a 4-point scale. Lifetime history of back pain occurrence and work were obtained from the families of 86 cadavers. To assess whether the risk of back pain changed with the severity of findings or the level of disc, we applied trend tests and proportional-odds logistic models for occurrence data.


RESULTS
In early adulthood, the risk of anular tears was 0.6 to 0.7, whereas at retirement age, tears were practically unavoidable. The risk of full anular tears with barium sulfate leaking ("leaking" tear) was estimated to be 0.10 and 0.35 among the men in the age groups of 20 to 49 and 50 to 59 years, respectively. The risk of "leaking" tears was greatest at the L5-S1 levels. There were less severe degenerative findings associated with sedentary occupation but no differences between driving and physically light and heavy occupations. Overall, the risk of any anular tears and any general degeneration as defined was similar. The frequency of back pain had a highly significant relation to the occurrence of tears (model-based P = 0.0009). With a "leaking" tear, the model-based estimate of the risk of frequent lifetime back pain was 0.42, with an "outer" tear the risk was 0.20, and with no tears or "inner" tears the risk was 0.10 (the observed prevalence was 0). The effect of occupational loading was of borderline significance (P = 0.045).


CONCLUSIONS
Anular degeneration of the lumbar discs appear earlier and are more clearly related to back pain than previously thought, most probably due to the better sensitivity of the BaSO4 discography method to detect tears.
Videman
Tapio
T
University of Alberta, Edmonton, Alberta, Canada. tapio.videman@ualberta.ca
Nurminen
Markku
M
D000328:Adult; D001466:Barium Sulfate; D002102:Cadaver; D003287:Contrast Media; D006801:Humans; D007278:Injections, Spinal; D007403:Intervertebral Disc / Q000000981:diagnostic imaging / Q000293:injuries / Q000473:pathology*; D007405:Intervertebral Disc Displacement / Q000150:complications / Q000175:diagnosis* / Q000503:physiopathology; D017116:Low Back Pain / Q000209:etiology / Q000473:pathology* / Q000503:physiopathology; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D013124:Spinal Injuries / Q000150:complications / Q000473:pathology / Q000503:physiopathology; D014057:Tomography, X-Ray Computed
D003287:Contrast Media; D001466:Barium Sulfate