Management of Supernumerary Lumbar Vertebrae
Supernumerary lumbar vertebrae are typically incidental anatomical variants that require no specific treatment unless they are associated with symptomatic conditions such as low back pain, scoliosis, or spinal stenosis. The management approach depends entirely on whether symptoms are present and what underlying pathology, if any, exists.
Initial Clinical Assessment
The key is determining whether the supernumerary vertebra is causing or contributing to symptoms:
- Document the exact spinal anatomy including the presence of transitional vertebrae (sacralization or lumbarization), as these commonly occur together with supernumerary ribs 1
- Assess for symptomatic conditions including low back pain, radiculopathy, neurogenic claudication, or spinal deformity
- Identify any "red flags" that would warrant immediate imaging or intervention 2
Management Algorithm
Asymptomatic Supernumerary Vertebrae
No treatment is indicated for incidentally discovered supernumerary lumbar vertebrae in asymptomatic patients. These are anatomical variants with no inherent pathology requiring intervention.
- Simply document the variant anatomy for future reference
- No imaging follow-up is needed unless symptoms develop
Symptomatic Presentations
If the patient presents with low back pain or other spinal symptoms, the supernumerary vertebra itself is rarely the direct cause—focus on identifying the actual pathology:
For Acute Uncomplicated Low Back Pain (<4 weeks)
Conservative management without imaging is the appropriate initial approach 2:
- Medical management with analgesics and NSAIDs 3
- Physical therapy and exercise programs 4, 3
- The condition is self-limiting in most patients, responsive to conservative care within 2-12 weeks 2
- Avoid early imaging (within first 4 weeks) as it provides no clinical benefit and leads to increased healthcare utilization without improving outcomes 2
For Chronic or Severe Symptoms
If symptoms persist beyond 3 months or worsen despite conservative management:
- MRI lumbar spine without contrast is the preferred imaging modality if surgical intervention is being considered 2
- Consider epidural steroid injections for radicular symptoms after failed conservative management 4
- Surgical consultation if neurologic deficits, spinal instability, or severe spinal stenosis develop 4, 3
Associated Scoliosis
Supernumerary vertebrae are commonly found in patients with scoliosis, particularly in Williams-Beuren syndrome where 73.6% have supernumerary ribs 1:
- Manage the scoliosis according to standard protocols
- The supernumerary vertebra itself does not require separate treatment
Critical Pitfalls to Avoid
- Do not attribute symptoms directly to the supernumerary vertebra without identifying actual pathology (disc herniation, stenosis, instability)
- Avoid unnecessary imaging in acute uncomplicated low back pain, as this leads to increased interventions without improved outcomes 2
- Ensure accurate vertebral counting when planning any spinal intervention, as transitional anatomy can lead to wrong-level surgery
- Do not perform fusion surgery that includes the supernumerary vertebra unless there is documented instability or other clear surgical indication 5
Long-Term Considerations
The natural history of degenerative changes is favorable with conservative management 3, 6: