The objective of this study was to determine the nature of the persist
ence of remnants of the original nutritive vascular canals within the
vertebral body and correlate their existence with end-plate ''weak spo
ts.'' The body-disc region of 20 lumbar vertebrae between the ages of
birth and 22 years was examined histologically to study the vascularit
y of the end-plate cartilage and its fate at the end of vertebral grow
th. Observations indicate a regression of the vascular canals in the e
nd-plate commencing in the first decade, with ''scars'' left by these
canals visible as nodular areas. By the beginning of the third decade,
herniation of the disc material into the weak spots was observed. It
is apparent that these weak spots represent a route for the early form
ation of intrabody nuclear herniations at this age (Schmorl's nodes).
(C) 1998 Wiley-Liss, Inc.