Diagnosis of Spondylolysis
Health care providers will do a thorough exam. During the exam, they might push on the back or ask a patient to bend backward to hyperextend the spine. If these things cause back pain, it's likely that there's a fracture in the pars.

Other things, such as muscle pain, a pinched nerve, or herniated (bulging) disc, also can cause lower back pain. To rule those out - or to confirm a diagnosis of spondylolysis - health care providers will order tests such as:

a back X-ray, which can show many fractures
a bone scan or a CT (computed tomography) scan, which can detect smaller fractures
a lumbar MRI scan