Central Spinal Stenosis

Discussion:

Central stenosis produces compression of the thecal sac in contrast to lateral stenosis which involves compression of individual nerve roots; - may be congenital (idiopathic or developmental in achondroplastic dwarfs) or acquired;

Acquired stenosis: - due to degenerative hypertrophic facets w/ medial encroachment (inferior facets most commonly involved); - can be secondary to spondylolisthesis, post traumatic, post surgical, Paget's disease, ect; - soft tissue (ligamentum flavum and disc) may contribute as much as 40% to dural sac compression; - central stenosis is more common in males because their spinal canal is smaller at the L3-L5 level;

Clinical Findings: - neurogenic claudication;

CT Scan: - compression of thecal sac to less than 100 mm squ or < 10 mm of AP diameter as seen on CT cross section; Ý

Treatment: - lumbar epidural steroids may be helpful for short term relief; - surgery is indicated in patients with positive studies and persistent symptoms;

Decompression: - laminectomy; - partial faceteotomy of the lateral recess; - can be done w/o destabilizing, thus avoiding fusion;

Fusion: - indicated in patients with surgical instability (bilateral facet joint removal); - neural arch defects with disc disease; - symptomatic radiographic instability ( > 4-6 mm horizonatal translation or reversal of the intervertebral angle); - degenerative spondylolisthesis; - degenerative Scoliosis;