Presentation
Lumbar back pain and progressive deformity. No neurology.
Patient Data
There is complete malalignment of the lumbosacral junction with almost complete anterior displacement of L5 on S1.
The CT confirms the plain film finding of anterior displacement of L5 on S1. The shape of L5 and associated sclerosis confirms that this is a longstanding abnormality.
As demonstrated on the CT and plain film, there is almost complete anterior displacement of L5 on S1. L5 is abnormal and there is marked loss of height posteriorly suggesting a longstanding process. Normal cord and canal.
Case Discussion
There is almost complete anterior displacement of L5 on S1. The shape of L5 with reduced posterior height and associated sclerosis (on the CT) suggest that this is the result of a longstanding progressive anterolisthesis secondary to bilateral pars defects. There is no underlying vertebral abnormality and the bone density appears normal.
Even when there is this degree of anterolisthesis, the spinal canal is not compromised.