Case 11
History
Back pain.
Findings
There is diffuse disk dessication and multilevel narrowing of the lower thoracic and lumbar spine with multilevel disc bulge or protrusion. There is spondylolisthesis of L4 on L5. There is close approximation of the spinous processes of the lower lumbar spine with sclerosis (low signal) and flattening of the adjacent spinous processes. There are focal fluid collections seen as high signal on the T2 sequence between the opposing spinous processes.
Discussion
Baastrups's disease is characterized on plain films by close approximation of spinous processes ("kissing spines") with associated sclerosis, enlargement and squaring off/ flattening of the involved spines. MR may document the development of adventitious bursae between the spines, seen as high signal fluid between the processes. Clinically there is midline tenderness. There may be pain exacerbated by extension and relieved by flexion, local anesthetic injection or surgical resection of the spinous processes/bursae.
A recent report cited below notes that intraspinal epidural posterior cysts associated with baastrup's disease may encroach upon the spinal canal and lead to central canal stenosis. Bursography has documented the contiguity of the epidural cysts with the interspinous bursae.
Reference
Chen CK et al : Intraspinal Posterior Epidural Cysts Associated with Baastrup's Disease: Report of 10 Patients AJR 2004; 182:191-194.
Submitted by Paul Clifford, MD and Steve Falcone, MD
