The influence of vertebral body fracture, intradiscal injection, and partial discectomy on the radial bulge and height of human lumbar discs.

The effects of vertebral body fracture, intradiscal injection, and partial discectomy on the radial extension and height of human lumbar discs have been investigated in vitro. Fracture and discectomy result in an increase of the radial disc bulge and a decrease of the disc height; intradiscal injection results in a decrease of the radial disc bulge and in an increase of the disc height. The significance of these changes is assessed by comparing them with those changes induced by load decrease or increase within the physiologic range. The results may explain clinical observations with regard to the persistence of or relief from low-back pain after fractures or after application of the therapeutic measures simulated in this experiment.