1. neoplastic; see Differential diagnosis: spine & spinal cord tumors for more:
a) metastatic tumors with a predilection for bone:prostate,breast,renal cell,lymphoma,thy- roid, lung…; see Spinal epidural metastases.
b) primary bone tumors:chordomas,osteoid osteoma,hemangioma
2. infection:
a) vertebral osteomyelitis: occurs mostly in IV drug abusers,patients with diabetes mellitus, and hemodialysis patients. May have associated spinal epidural abscess. Also see Vertebral osteomyelitis
b) Discitis
3. chronic renal failure: some patients develop a destructive spondyloarthropathy that resembles infection11,12
4. ankylosing spondylitis: bamboo spine (square VBs with bridging syndesmophytes)
5. lesions producing posterior scalloping of VB (mnemonic: AMEN)
A acromegaly or achondroplasia
M Marfan syndrome or mucopolysaccharidosis
E Ehlers-Danlos
N neurofibromatosis
also: dural ectasia
6. lesions producing anterior scalloping of VB
a) aortic aneurysm
b) lymphoma
c) spinal TB