II. Definitions
- Spondylolysis
- Vertebral defect at pars interarticularis (one or two defects)
- When two, bilateral Pars Defects occur, Spondylolisthesis (Vertebral slippage) occurs
III. Epidemiology
- Uncommon cause of back pain in general population, non-athletes
-
Incidence in age <40 years old: 6%
- Spondylolisthesis is much less common, and typically at L5-S1
- Pars Interarticularis Defect is twice as common in men
- However women have higher risk of high grade Spondylolisthesis
- Common cause of back pain in athletes (esp. repeated spine extension)
- Gymnastics, ballet or dance
- Football (e.g. blocking, lineman)
- Volleyball (e.g. serving the ball)
- Soccer
- Weightlifting
- Diving
- Baseball Players
IV. Pathophysiology
- Repetitive back hyperextension
- Most commonly occurs at L4 or, especially L5
- Results in Fracture at pars interarticularis resulting in Pars Interarticularis Defect
- One Pars Defect: Spondylolysis
- Two Pars Defects: Spondylolisthesis
V. Symptoms
- History should include Cauda Equina Syndrome symptoms and other cord compression symptoms
- Back pain exacerbated by Lumbar Spine hyperextension
- Radiation into posterior legs
VI. Signs
- Perform complete Neurologic Exam of lower extremity
- Hyperlordotic curvature of the Lumbar Spine
- Decreased Lumbar Spine range of motion
- Hamstring tightness
- Quadriceps tightness
- Altered gait (crouched position)
-
One Legged Hyperextension (Stork Standing Test)
- Examiner stands behind patient for support
- Patient balances on one leg and hyperextends back
- Positive if pain at affected lumbar Vertebrae
VII. Imaging: XRay
- Indicated for back pain lasting >3 weeks (esp. athletes)
- Views: AP, lateral and oblique views
- Findings: Scotty Dog Sign on oblique view
- Identify landmarks corresponding to Scotty Dog
- Head of Scotty Dog: Superior articular process
- Neck of Scotty Dog: Pars interarticularis
- Front leg of Scotty Dog: Inferior articular process
- Body and back leg of Dog: Transverse process
- Findings consistent with Spondylolysis
- Collar on Scotty Dog neck: Fracture through pars
- Identify landmarks corresponding to Scotty Dog
- Pitfalls
- Pars Fracture often not seen in early Spondylolysis
VIII. Imaging: Advanced Imaging
- MRI L-Spine
- Preferred imaging for non-diagnostic XRay
- MRI sequenced for pedicle and pars region Bone Marrow edema
- Single photon emission computed tomography (SPECT)
- Most sensitive for Spondylolysis
- Consider for nondiagnostic XRay
- CT L-S Spine (thin cut, reverse gantry CT)
- Highly specific for Spondylolysis
- Consider for positive SPECT scan
- Differentiates acute versus chronic Spondylolysis
IX. Management
- Consider 6 weeks of conservative therapy if XRay negative, but suspect Spondylolysis
- NSAIDs
- Relative rest period with no sports activity
- Chronic Spondylolysis: Rest until no pain
- Acute Spondylolysis: Rest minimum of 3 months
- Adjunctive measures
- Low Thoracolumbar Orthosis bracing could be considered at 3 weeks of rest
- Taper the Orthosis to pain free status (regardless of imaging)
- Transcutaneous electrical nerve stimulation (TENS)
- Consider repeat imaging to survey acute injury for healing
- Low Thoracolumbar Orthosis bracing could be considered at 3 weeks of rest
- Rehabilitation program
- Quadriceps and Hamstring flexibility
- Spine stabilization (flexion, core Muscle)
- Low-impact aerobics
- Progress to sport-specific activity
- Gradual return to activity over a 5 month period
- Orthopedics or Spine Surgery referral indications
- Spondylolysis refractory to above management (<10% of cases)
X. Complications
XI. References
- Connolly (1995) Fractures and Dislocations, p. 443-4
- Achar (2020) Am Fam Physician 102(1):19-28 [PubMed]
- Cassas (2006) Am Fam Physician 73:1014-22 [PubMed]
- Standaert (2002) Clin J Sports Med 12:119-22 [PubMed]