INGROWTH OF BLOOD-VESSELS IN DISC DEGENERATION - ANGIOGRAPHIC AND HISTOLOGICAL STUDIES OF CADAVERIC SPINES

Angiograms were made of twenty-two cadaveric lumbar spines to determin e the presence of any new blood vessels between adjacent lumbar verteb rae and corresponding discs. The annulus and adjacent longitudinal lig aments were also analyzed histologically. A total of 105 intervertebra l spaces were studied. It was found that the normal anastomosing arter ies in the posterior longitudinal ligament were significantly oblitera ted with advancing degeneration of the disc (p < 0.001), whereas sever al tiny tortuous arteries - often running between the osteophytic spur s - were seen in the anterolateral aspects of the intervertebral space s connecting the adjacent vertebrae. Histological examination of the a nterolateral part of the annulus showed that the vascularity of the an nulus increased significantly,vith degeneration of the disc (p < 0.001 ), and most of the arteries had a vertical orientation. Regression ana lysis showed that vascular changes occurred before degeneration of the disc at every lumbar level, suggesting that disturbances in the nutri tional supply may precede degeneration. The correlation coefficient wa s 0.77 (95 per cent confidence limit, 0.52 to 0.90) for the increase i n annular vascularity with an increase in the age of the individual at the time of death and 0.86 (95 per cent confidence limit, 0.69 to 0.9 4) for the increase in degeneration of the disc with an increase in ag e.