Baastrup's Disease: An Often Missed Etiology for Back Pain.

Baastrup's disease is a relatively common disorder of the vertebral column, characterized by low back pain arising from the close approximation of adjacent posterior spinous processes and resultant degenerative changes, most commonly at L4-L5. Though fairly common, Baastrup's disease is overwhelmingly underdiagnosed and often missed due to a lack of knowledge and/or improper diagnostic techniques, leading to frequent mistreatment. We present a case of a 56-year-old man who presented with chronic, ongoing low back pain of several years duration. His pain was relieved by flexion of the spine, and aggravated by extension. Imaging studies revealed "kissing" posterior spinous processes, consistent with a diagnosis of Baastrup's Disease. He was treated with subcutaneous steroid injections and showed considerable clinical improvement.