A fracture or a fissure in the arch of one of the vertebrae in the lower lumbar area of the vertebral spine is known as spondylolysis. It may occur abruptly or following a series of shocks and of stresses. Sometimes the disease is hereditary. Often, spondylolysis does not cause any symptom, and the patients may have this disease all their life without knowing. este Spondylolisthesis is a continuation of spondylolysis, where the vertebral arch breaks, and the vertebra slides out of the line (usually towards forward. .
This disease may occur if joints with facets wear out with age, allowing the vertebra to slide. If the sliding of the vertebra engages the ligament and nervous structures, paresthesia may occur in the leg area.
The most frequent localization is at the level of vertebra L5 due to the high mechanic stress. Spondylolisthesis has 5 staging degrees: I degree the vertebra slides on less than de 25% of the upper area of the subjacent vertebra, II degree – the sliding is between 25-50%, III degree – 50%-75%, IV degree:75%-100%, V degree over 100% (spondyloptosis). The treatment is conservative or surgical.