aetiology and pathology

Last reviewed 01/2018

Normally, slipping of one vertebrae upon the another is prevented by the engagement of its articular process with those of the segment next below it. A failure of this check mechanism produces spondylolisthesis. This may arise in five situations:

• slipping at a spondylolysis of the pars interarticularis:
• caused by a fatigue fracture
• the most common form of spondylolisthesis

• degenerative osteoarthritis:
• mechanical wear of the posterior facet joints may result in vertebral slipping
• the main problem is degenerative disc disease
• it is most most common in women over the age of 55 years

• dysplastic:
• a congenital deficiency of the posterior facet joints
• this is most common at the lumbo-sacral joint allowing the L5 vertebra to slip forwards off S1
• it is a rare condition, more common in girls than boys
• complete displacement may produce a cauda equina syndrome

• trauma - very rarely, spondylolisthesis may result from an acute traumatic fracture, or a pathological fracture through a tumour

• pathological - weakening of the pars interarticularis by tumours and osteoporosis