Spondylolysis
Spondylolysis is a stress fracture or defect of the vertebral pars interarticularis, most often at L5, common in preadolescent and adolescent athletes who repeatedly extend and rotate the spine, treated first with activity modification and NSAIDs and reserving imaging escalation and bracing for persistent or progressive symptoms.
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What this article covers
- Overview
Spondylolysis is a fracture or defect of the vertebral pars interarticularis, the bony bridge between the superior and inferior articular facets, most often affecting L5.
- Epidemiology
Most common in preadolescent and adolescent athletes engaged in sports with repetitive back extension and rotation, including gymnastics, diving, weightlifting, and football.
- Risk factors
Sports with repetitive lumbar extension and rotation, particularly gymnastics, diving, weightlifting, and football (linemen), which load the pars interarticularis with repeated hyperextension.
- Pathophysiology
Repetitive extension and rotation load the pars interarticularis beyond its capacity to remodel, producing a stress reaction that can progress to a frank fracture if loading continues unmodified.
- Clinical features
Unilateral or midline low back pain that is worse with lumbar extension and rotation and improves with flexion and rest, the hallmark presentation; pain is typically insidious rather than from a single traumatic event.
- Differential diagnosis
Spondylolisthesis: a palpable lumbosacral step-off and, in higher-grade slips, radiculopathy or bowel/bladder symptoms distinguish anterior vertebral translation from an isolated, non-displaced pars defect.
- Diagnosis
Spondylolysis is confirmed by imaging demonstrating a defect or stress reaction of the pars interarticularis; a completed fracture shows a lucent line with sclerotic, corticated margins if chronic…
- Management
First, modify activity: restrict the provocative extension-rotation sport (gymnastics, diving, weightlifting, football) while continuing non-provocative conditioning, since unloading the pars is the…
- Complications
Progression to spondylolisthesis: a bilateral pars defect can allow anterior vertebral translation across serial follow-up radiographs, particularly during residual growth; see spondylolisthesis.
- Prognosis
Usually complete recovery with activity modification, NSAIDs, and physical therapy, particularly for an isolated, unilateral, non-displaced defect identified early.
- Prevention
Limit cumulative extension-rotation training load in high-risk sports (gymnastics, diving, weightlifting, football) to no more than a graded 10% weekly increase in training volume, through structured…
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Related articles
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Spondylolisthesis is anterior displacement of a vertebral body, usually L5 on S1, through a bilateral pars interarticularis defect in children and adolescent athletes or through degenerative facet disease in older adults, graded by percentage slip on a lateral radiograph and managed with activity modification and NSAIDs for low-grade disease, escalating to fusion for a high-grade or progressive slip with neurologic compromise.
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- Ankylosing spondylitis
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