Overview

Terminology: Spondylo (Spine) Lysis (Break) Listhesis (Slip)

This condition is commonly present in about 5% of the population and may be asymptomatic

  • Dysplastic is usually a congenital abnormally of the facets and posterior elements.
  • Isthmic (pars) is the bony zone between the facet joints a region subject to break.
    • lytic (stress fracture),
    • elongated (repetitive micro-fractures with /healing
    • acute fracture (single event)

Activity-related with onset of low back pain., usually around the L5-S1. Typical in persons with a history of trauma – commonly among gymnasts, linemen, wrestlers.

  • Slip more than 50%, adolescent growth spurt, in females
  • Lysis: females less than males (2:1), listhesis females greater than males (4:1)
  • Radiculopathy is pain radiating to the lower extremities
    • Lysis may lead to scar tissues formation
    • Dysplastic – with stretch on affected nerve roots by the intact arch
    • Isthmic – narrowing of the nerve root canal (foraminal stenosis)

Clinical Exam

  • Lumbar hyperlordosis/ flat buttocks
  • Tight hamstring
  • Crouched gait/ tilted pelvis

Imaging

  • Plain X-rays in the standing position with oblique side view
  • CT– best for bony pathology; localize lesion; confirm diagnosis; plan surgery
  • MRI –
    • Neuro deficit or unusual presentation
    • Adjacent level hydration status
  • SPECT or bone scan with increased uptake may indicate the potential of the break to heal in children.

Surgical Options

  • Pars Repair: Good for spondylolysis with low grade slip in children
  • Fusion in Situ: High fusion rate for single level L5-S1 and low grade with or without instrumentation
  • Posterior Fusion with interbody Fusion (TLIF/PLIF)
  • The type of surgery should be tailored to patient symptoms, Degree of slippage and neurologic status

The Role of instrumentation

  • Higher fusion/complication rates

Anterior Fusion will increase arthrodesis rate

  • High grade slips have a high incidence of neurologic complication if reduction is attempted. The slip angle reduction is more relevant than percent slip reduction for a good functional outcome.