What are common reasons to obtain an additional oblique view in the lumbar spine?

What are common reasons to obtain an additional oblique view in the lumbar spine?

• A. To evaluate scoliosis.
• B. To assess bone mineral density.
• C. To assess pars interarticularis for spondylolysis and to evaluate facet joints.
• D. To measure disc height.

Answer: (C)

The main point is that oblique views of the lumbar spine are specifically used to look at the posterior elements: the pars interarticularis and the facet joints. When the patient is rotated into an oblique projection, the pars interarticularis is brought into an optimal plane to be seen clearly. This makes it possible to detect spondylolysis, which is a stress fracture in the pars interarticularis, a finding that is especially common in young athletes. On oblique views you can also assess the facet joints more readily because their joints are seen in profile, allowing evaluation of joint space and potential facet arthropathy. Other options aren’t as well suited for these purposes. Evaluating scoliosis relies more on full-length PA and lateral views to assess curvature in the coronal plane. Bone mineral density cannot be reliably assessed on a lumbar oblique radiograph and typically uses dedicated DEXA imaging. Measuring disc height is best done on a lateral view where the vertebral bodies and intervertebral discs are viewed in profile.

The main point is that oblique views of the lumbar spine are specifically used to look at the posterior elements: the pars interarticularis and the facet joints. When the patient is rotated into an oblique projection, the pars interarticularis is brought into an optimal plane to be seen clearly. This makes it possible to detect spondylolysis, which is a stress fracture in the pars interarticularis, a finding that is especially common in young athletes. On oblique views you can also assess the facet joints more readily because their joints are seen in profile, allowing evaluation of joint space and potential facet arthropathy.

Other options aren’t as well suited for these purposes. Evaluating scoliosis relies more on full-length PA and lateral views to assess curvature in the coronal plane. Bone mineral density cannot be reliably assessed on a lumbar oblique radiograph and typically uses dedicated DEXA imaging. Measuring disc height is best done on a lateral view where the vertebral bodies and intervertebral discs are viewed in profile.