Posterior Vertebral Scalloping

The mnemonic AMEN can be used to remember the differential diagnosis for the appearance of scalloped posterior vertebral bodies.

• Acromegaly: Caused by soft tissue hypertrophy and bone resorption
• Achondroplasia: Caused by a small spinal canal. May also see caudal narrowing of the spinal canal.
• Ankylosing spondylitis: Caused by dural ectasia
• Marfan syndrome: Caused by dural ectasia
• Mucopolysaccharidoses (Morquio disease and Hurler syndrome): May also see platyspondyly and anterior vertebral body beaks.
• Ehlers-Danlos syndrome: Caused by dural ectasia
• Neurofibromatosis: Caused by dural ectasia. May also see scoliosis and syringomyelia

Hydrocephalus and intraspinal tumors may also cause scalloping via increased intraspinal pressures, but they don't fit in the mnemonic.

References

Wakely SL. The posterior vertebral scalloping sign. Radiology. 2006 May;239(2):607-9.