What is the recommended management for a patient presenting with low back pain and radicular symptoms due to Bertolotti syndrome (lumbosacral transitional vertebra)?

Management of Bertolotti Syndrome

For patients with Bertolotti syndrome presenting with low back pain and radicular symptoms, begin with conservative management including physical therapy, NSAIDs, and neuropathic pain medications; if symptoms persist beyond 3 months or are severe/disabling, proceed to fluoroscopically-guided diagnostic injections at the pseudoarticulation, and reserve surgical resection (pseudoarthrectomy) only for patients who demonstrate clear symptomatic improvement with targeted injections but have recurrent symptoms.

Initial Diagnostic Approach

The critical first step is confirming the diagnosis with advanced imaging (CT or MRI of the lumbosacral spine), as plain radiographs frequently miss lumbosacral transitional vertebrae (LSTV). Look specifically for:

• Enlarged L5 transverse process(es) with pseudoarticulation or fusion with the sacrum
• Castellvi classification Type II (pseudoarticulation present) or Type III (complete fusion)
• Exclusion of more obvious pain generators (disc herniation, spinal stenosis, facet arthropathy)

Critical caveat: LSTVs are common (4-36% prevalence) and often asymptomatic 1. The anatomical finding alone does not confirm Bertolotti syndrome—you must establish causality through the clinical presentation and response to targeted interventions.

Conservative Management (First-Line: 3-6 Months)

Start all patients with a structured conservative approach:

• Physical therapy focusing on lumbosacral myofascial release and therapeutic exercises targeting the thoracolumbar fascia and quadratus lumborum 2
• NSAIDs for anti-inflammatory effect
• Neuropathic pain medications (gabapentinoids, SNRIs) since radicular pain from LSTV often has neuropathic characteristics [@2-9@]
• Activity modification avoiding provocative movements

Avoid strong opioids or use only at the lowest dose for the shortest duration with close monitoring, given lack of long-term benefit evidence and significant harm potential [@2-9@].

Timing for Specialist Referral

Severe/Disabling Symptoms or Neurological Deficit

• Refer within 2 weeks if pain is disabling (prevents normal daily activities) or if sensory/motor deficits are present in the L5 distribution [@2-9@]

Less Severe Radicular Pain

• Refer to specialist services no later than 3 months if conservative management fails [@2-9@]

Young Patients (<30 years)

• Maintain higher index of suspicion given the congenital origin of LSTV 1
• Consider earlier specialist evaluation if symptoms persist beyond 6-8 weeks

Interventional Management (Second-Line)

When conservative management fails, the evidence supports a diagnostic and therapeutic injection strategy:

Fluoroscopically-Guided Pseudoarticulation Injection

• Target the L5/S1 pseudoarticulation specifically with local anesthetic ± steroid
• This demonstrates significantly better symptomatic improvement compared to other injection locations (facet, epidural, trigger point) 3
• Fluoroscopic guidance is the gold standard—blind injections should not be performed [@2-9@]
• Patients responding well to pseudoarticulation injections are candidates for surgical consideration 3

Alternative: Radiofrequency Ablation

• RFA targeting the L4 medial branch, L5 dorsal ramus, and S1 lateral branch may provide sustained relief 4
• Consider this for patients with bilateral Bertolotti joints or those seeking longer-lasting relief than injections provide

Important contradiction in evidence: The 2025 BMJ guideline 5 provides strong recommendations AGAINST most spinal injections for chronic low back pain, citing lack of evidence for improved morbidity/mortality and potential harms. However, this guideline addresses non-specific low back pain, not the specific anatomical pathology of Bertolotti syndrome. The targeted pseudoarticulation injection has demonstrated specific diagnostic and therapeutic value in this population 3.

Surgical Management (Third-Line)

Indications for Surgery

Reserve surgical intervention for patients who:

1. Demonstrate clear improvement with pseudoarticulation injections (confirming the LSTV as pain generator)
2. Have recurrent symptoms requiring repeated injections
3. Have failed at least 3-6 months of conservative management
4. Are appropriately counseled on risks and have realistic expectations

Surgical Options

Pseudoarthrectomy (Resection of Pseudoarticulation)

• Partial resection of the hypertrophic L5 transverse process and sacral alar
• Decompression of the L5 nerve root
• Can be performed via open technique or minimally invasive endoscopic approach (unilateral biportal endoscopic spinal surgery) 6
• Demonstrates significant pain relief in carefully selected patients 3, 7

Fusion vs. Resection Alone

• The literature is limited and variable on whether fusion should accompany resection 1
• Consider fusion if there is concern for adjacent segment instability or if multiple levels are involved
• Biomechanical alterations from LSTV predispose to adjacent segment disease, complicating this decision 1

Surgical Outcomes

Recent case series show:

• Significant improvement in VAS pain scores (from 8/10 to 1-2/10 postoperatively) 6
• Sustained benefit at 6-24 month follow-up 7
• Complete resolution of radicular symptoms in most cases 6, 7
• No neurological complications in recent series 7

Common Pitfalls to Avoid

1. Failure to identify the LSTV: 33% of patients with LSTV have it missed by providers, leading to multiple ineffective injections at wrong locations 3

2. Assuming all LSTVs are symptomatic: The anatomical variant is common; establish causality through clinical correlation and response to targeted interventions

3. Premature surgery: Patients who undergo surgery without demonstrating response to pseudoarticulation injections have less predictable outcomes

4. Inadequate imaging: Plain films miss many LSTVs—obtain CT or MRI when clinical suspicion exists

5. Wrong injection targets: Non-targeted epidural, facet, or trigger point injections are less effective than pseudoarticulation-specific injections 3

Biopsychosocial Considerations

Conduct a biopsychosocial assessment before proceeding with invasive interventions [@2-9@]. Patients with significant psychosocial factors, catastrophizing, or secondary gain may benefit from cognitive behavioral therapy alongside physical treatments. This is particularly important given the chronic nature of symptoms in many patients.