pars defect
Pronunciation: parz DEE-fekt
A stress fracture or defect in the pars interarticularis, the bony connection between vertebral facets.
Full Definition
A pars defect, also called pars interarticularis defect, is a stress fracture or discontinuity in the narrow portion of bone connecting the superior and inferior articular processes of a vertebra. This condition is most common at L5 and is frequently seen in young athletes participating in sports involving repetitive hyperextension and rotation. The defect may be unilateral or bilateral and can be associated with spondylolisthesis if bilateral. Diagnosis is typically made with CT imaging, though SPECT scanning may be useful for detecting early stress reactions.
Usage
Usage note: Specify unilateral vs bilateral and associated listhesis grade when present; pars defect and spondylolysis are synonymous.
In Context
- "CT scan demonstrated a bilateral pars defect at L5 with Grade I spondylolisthesis." — radiology report
- "The young gymnast developed a pars defect from repetitive hyperextension activities." — sports medicine consultation