ETIOLOGY AND PATHOGENESIS OF SPONDYLOLISTHETIC SPONDYLOLISTHESIS

The commonly accepted hypothesis set up by Brocher in 1950 that the dy splasia of the pars interarticularis vertebrae is an essential require ment for the occurrence of spondylolysis should be thought over in lig ht of recent findings. Newly published investigations show that distur bed spinal growth leads to dysplasia of the vertebral arch and to spon dylolysis. Disturbances that play an important role are biomechanical stress factors that result from the evolution from a quadripedal to a bipedal human locomotion as well as stress fractures of the vertebral pars interarticularis and defects in vertebral maturation in small inf ants.