Imaging recommendation · Musculoskeletal

Adolescent athlete (gymnast, dancer) with low back pain, suspected pars defect

Q: What's the alternative imaging for adolescent athlete (gymnast, dancer) with low back pain, suspected pars defect when bony detail / planning?

CT — Limited CT lumbar with thin slices (no contrast).

Q: What's the alternative imaging for adolescent athlete (gymnast, dancer) with low back pain, suspected pars defect when activity / functional assessment?

NM — SPECT/CT bone scan (iv contrast).

Recommended: MRI Lumbar Spine (STIR for early stress reaction) is the preferred imaging study for adolescent athlete (gymnast, dancer) with low back pain, suspected pars defect. Pars interarticularis stress fracture, most common at L5.

Recommended study

MRI Lumbar Spine (STIR for early stress reaction)

MRI No contrast Preferred Musculoskeletal Outpatient Reviewed 2026-05

Pars interarticularis stress fracture, most common at L5. Bilateral defects → spondylolisthesis.

If the default doesn't apply

Bony detail / planning

CT Limited CT lumbar with thin slices No contrast

Activity / functional assessment

NM SPECT/CT bone scan IV contrast

Watch-outs

Spondylolisthesis grades

Meyerding I-V; high-grade slips may need surgical fusion.

Pearls

Scotty dog 'collar' on oblique X-rays — pars defect.
MRI STIR: pars edema is earliest finding before frank fracture.
Bracing + activity restriction for active lesions; chronic stable lesions often asymptomatic.