Use of lumbosacral spine radiographs in a level II emergency department

We studied indications for lumbosacral spine radiographs in an emergency department setting.

Clinicians completed a lumbosacral spine request form before obtaining lumbosacral radiographs on 482 patients who were examined in a level II emergency department. The clinicians detailed the indications for the examination, their suspected clinical diagnoses, and the expected effect of the lumbosacral spine study on management. In addition, the duration of the patients' symptoms was recorded as well as their age and sex. These data were compared with the actual radiographic findings as interpreted by board-certified musculoskeletal radiologists.

Major indications for lumbosacral radiographs were lower back pain (92%) and trauma (36%). Patient expectation and medicolegal concerns, related either to insurance documentation or to physician litigation, were cited in 42% of cases. A neurologic deficit was present in 88% of patients, and a history of neoplasm was elicited in 4%. Strain (56%) and fracture (20%) were the most commonly suspected clinical diagnoses. Radiographs showed either normal findings or spondylosis in 86% of cases. Fractures, of which 10 were definitely acute, were identified in 55 patients. No fracture required decompression. Neoplastic involvement was found in seven patients, all of whom had histories of osseous metastases. Neurologic deficit, present in 37 patients, did not correlate with abnormalities seen on lumbosacral radiographs.

As with studies of lumbosacral spine radiographs obtained in outpatient settings, our data from a level II emergency department support the use of lumbosacral spine radiographs for patients with a history of trauma, even if relatively minor, in elderly patients and in patients with lower back pain who have a history of neoplasm. Lumbosacral radiographs obtained for an isolated complaint of lower back pain generally provide no clinically useful information. Similarly, lumbosacral radiographs obtained for patients with isolated neurologic abnormalities are unrevealing. Such patients are better examined (although not necessarily at the time of emergency department evaluation) with techniques such as MR imaging that show soft-tissue lesions.