What is the recommended treatment for a patient with mild L5‑S1 retrolisthesis, diffuse disc bulge and left paracentral/subarticular broad‑based protrusion causing moderate central canal and left lateral recess stenosis and mild bilateral foraminal narrowing, without acute neurological deficits?

Treatment for L5-S1 Retrolisthesis with Moderate Stenosis and Disc Protrusion

Begin with a minimum of 6 weeks of comprehensive conservative management including formal physical therapy, neuropathic pain medications (gabapentin or pregabalin), anti-inflammatory therapy, and consider epidural steroid injections before any surgical intervention. 1, 2

Initial Conservative Management (Mandatory First-Line)

Conservative treatment must be completed for at least 6 weeks to 3 months before considering surgical options, as subacute to chronic low back pain with or without radiculopathy is a self-limiting condition responsive to medical management and physical therapy in most patients. 1

Required conservative measures include:

• Formal, supervised physical therapy program for minimum 6 weeks (not just home exercises) 1, 2
• Neuropathic pain medications (gabapentin or pregabalin) for radicular symptoms 2
• Anti-inflammatory therapy (NSAIDs or prednisone course) 2
• Epidural steroid injections at L5-S1 if radiculopathy persists, though relief typically lasts less than 2 weeks 2
• Remaining active and avoiding prolonged bed rest 1

When to Consider Surgical Intervention

Surgery becomes appropriate only after 6 weeks of optimal conservative management has failed AND the patient is a surgical candidate. 1 The goal of imaging and surgery is to identify and treat actionable pain generators causing persistent or progressive symptoms. 1

Surgical Indications for Your Specific Pathology

Your imaging findings (retrolisthesis + moderate stenosis + disc protrusion) meet fusion criteria IF:

1. Documented instability on flexion-extension radiographs (any degree of spondylolisthesis or retrolisthesis with motion) 1, 2
2. Moderate-to-severe stenosis requiring extensive decompression that might create iatrogenic instability 1, 2
3. Persistent disabling symptoms after completing conservative management 1, 2

Decompression with fusion provides superior outcomes (93-96% excellent/good results) versus decompression alone (44% good outcomes) when stenosis is combined with any degree of listhesis. 2 Patients treated with decompression/fusion report statistically significantly less back pain (p=0.01) and leg pain (p=0.002) compared to decompression alone. 2

Surgical Approach if Conservative Management Fails

For Stenosis WITHOUT Documented Instability:

Decompression alone (laminectomy/foraminotomy) is sufficient if no instability is present on dynamic imaging and less than 50% of facet removal is required. 1, 2

For Stenosis WITH Retrolisthesis/Instability:

Decompression with instrumented fusion is recommended as Class II medical evidence supports fusion following decompression in patients with lumbar stenosis and spondylolisthesis. 1, 2

Recommended surgical technique:

• Transforaminal Lumbar Interbody Fusion (TLIF) at L5-S1 with pedicle screw fixation provides fusion rates of 92-95% 2, 3
• Bilateral foraminotomy for bilateral foraminal stenosis 4, 5
• Instrumented fusion with pedicle screws provides optimal biomechanical stability with fusion rates up to 95% 2

Critical Pitfalls to Avoid

Do NOT proceed to fusion without:

• Completing minimum 6 weeks of formal physical therapy 1, 2
• Obtaining flexion-extension radiographs to document instability 1
• Confirming that imaging findings correlate with clinical symptoms 1

Avoid fusion if:

• Only isolated axial back pain without radiculopathy or stenosis 2
• No documented instability on dynamic imaging 1, 2
• Conservative management has not been adequately attempted 1, 2

The incidence of delayed progressive spondylolisthesis after decompression alone ranges from 9% (without preoperative instability) to 73% (with preoperative spondylolisthesis), making fusion particularly important when any degree of listhesis is present preoperatively. 1

Expected Outcomes with Appropriate Treatment

If fusion is performed for appropriate indications:

• 93-96% report excellent/good outcomes 2
• Significant improvements in ability to perform activities, participate socially, sit, and sleep 2
• Fusion rates of 92-95% with modern instrumented techniques 2, 3

Retrolisthesis specifically may result in somewhat worse postoperative bodily pain and physical function scores compared to patients without retrolisthesis, though the differences in disability and sciatica scores are not significant. 6 This suggests the retrolisthesis component may contribute ongoing pain even after disc decompression.