Spondylolisthesis-
Spodylolisthesis is a forward translation of one vertebral body on another. It is most common in the lower lumbar spine.
Classification of spondylolisthesis:
| 1) Isthmic - | the
basic lesion is in the pars interarticularis a) Lytic : fatigue fracture of pars b) Elongated but intact pars c) Acute pars fracture |
| 2) Dysplastic - | congenital abnormality at the lumbosacral junction, due to a deficiency of the upper sacrum or dysplasia of the posterior arch of L5 |
| 3) Degenerative - | due to degenerative arthritis of the facet joints and long-standing intersegmental instability. It is much more common in females and far more common at the L4-L5 level than at the L5-S1 level. |
| 4) Traumatic | |
| 5) Pathologic - | due to metabolic bone disease, tumor or after surgery |
| Meyerding's scale: | |
| Grade | Amount of subluxation |
| 1 | <25% |
| 2 | 25-50% |
| 3 | 50-75% |
| 4 | 75-100% |
| 5 | >100% |
|
Degenerative
Spondylolisthesis at the L4-L5 Level |
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