Anatomy Msk · Year 1 · from Anatomy Msk
Case 2: Spondylolisthesis
Clinical Image
Source: Wikimedia Commons - Spondylolisthesis - Public Domain
Case Presentation
A 16-year-old competitive gymnast presents with chronic low back pain that has worsened over the past 6 months. She describes the pain as a dull ache in her lower back, worse with extension-based activities such as backbends and dismounts. The pain occasionally radiates into her buttocks but not below the knees. She denies lower extremity weakness, numbness, or bowel/bladder dysfunction. Physical examination reveals hyperlordosis of the lumbar spine. Pain is reproduced with lumbar extension and single-leg hyperextension (stork test) bilaterally. There is palpable step-off at the L5 spinous process. Neurological examination is normal. Lateral standing radiographs reveal Grade II (26-50% slip) anterolisthesis of L5 on S1 with bilateral pars interarticularis defects visible on oblique views (spondylolysis). The "Scottie dog" appearance shows the collar representing the pars defect. She is placed in a thoracolumbosacral orthosis (TLSO) brace, restricted from gymnastics, and begins physical therapy focusing on core stabilization and hip flexor stretching.
Key Learning Points
- Spondylolysis is a defect in the pars interarticularis, often a stress fracture from repetitive hyperextension
- Spondylolisthesis is anterior slippage of one vertebra on another, commonly occurring when bilateral pars defects are present
- L5-S1 is the most common level (90%) due to the lumbosacral angle and mechanical stress
- The Meyerding classification grades slip severity: I (0-25%), II (25-50%), III (50-75%), IV (75-100%), V (spondyloptosis)
- Young athletes in extension sports (gymnastics, diving, football linemen) are at highest risk