CT outperforms radiographs at a comparable radiation dose in the assessment for spondylolysis.

Background: Lumbar spondylolysis, a unilateral or bilateral fracture at pars interarticularis, is a common cause of low back pain in children. The initial imaging study in the diagnosis of lumbar spondylolysis has historically been lumbar spine radiographs; however, radiographs can be equivocal or false-negative. Definitive diagnosis can be achieved with computed tomography (CT), but its use has been limited due to the dose of ionizing radiation to the patient.