What is the management for posterior disc space narrowing at L5-S1 with slight retrolisthesis of L5 on S1 and mild levoscoliosis?

Management of L5-S1 Disc Space Narrowing with Retrolisthesis and Mild Levoscoliosis

Conservative management with structured physical therapy for at least 6 weeks is the initial treatment approach for L5-S1 disc space narrowing with slight retrolisthesis, reserving surgical fusion only for cases with documented instability, persistent disabling symptoms after comprehensive conservative treatment, or progressive neurological deficits. 1, 2

Initial Conservative Management

Begin with a minimum 6-week trial of comprehensive conservative treatment before considering any surgical intervention. 2, 3

• Formal physical therapy focusing on core strengthening exercises, flexibility training, and proper body mechanics is essential 3
• Pain management with NSAIDs or acetaminophen as first-line pharmacologic treatment 3
• Neuroleptic medications (gabapentin or pregabalin) should be trialed if radicular symptoms are present 2
• Remain physically active rather than bed rest, as activity is more effective for low back pain 3
• Patient education about the generally favorable prognosis of degenerative disc disease 3

Important Caveat About Retrolisthesis

Retrolisthesis alone at L5-S1 is not associated with worse baseline pain or function compared to disc pathology without retrolisthesis. 4 The prevalence of retrolisthesis in patients with L5-S1 disc herniation is 23.2%, and its presence does not predict increased preoperative low back pain or physical dysfunction 4. This means your imaging findings may not correlate with symptom severity.

When to Consider Advanced Interventions

Proceed to advanced imaging or interventional procedures only if:

• Symptoms persist or progress after 6 weeks of conservative management 3
• Neurological deficits develop (progressive weakness, sensory changes, bowel/bladder dysfunction) 3
• Functional impairment remains significant despite conservative measures 2

Interventional Options Before Surgery

• Epidural steroid injections may provide short-term relief (less than 2 weeks duration) for radicular symptoms, though evidence is limited for chronic low back pain without radiculopathy 2
• Facet joint injections can be both diagnostic and therapeutic, as facet-mediated pain causes 9-42% of chronic low back pain 2

Surgical Indications

Lumbar fusion at L5-S1 should be reserved for specific criteria being met: 1, 2

Absolute Requirements for Fusion

1. Documented instability on flexion-extension radiographs showing dynamic movement 2
2. Failure of comprehensive conservative management for 3-6 months including formal physical therapy, medication trials, and possibly injections 1, 2
3. Significant functional impairment persisting despite conservative measures 2
4. Pain that correlates directly with degenerative changes on imaging 2

Additional Fusion Indications

• Spondylolisthesis with instability (your slight retrolisthesis may not meet this threshold unless dynamic instability is demonstrated) 2
• Extensive decompression that might create iatrogenic instability 2, 5
• Post-laminectomy syndrome with documented instability 2

Surgical Technique Considerations (If Criteria Met)

If fusion becomes necessary after failed conservative management, transforaminal lumbar interbody fusion (TLIF) at L5-S1 provides high fusion rates (92-95%) and allows simultaneous decompression. 2

• Pedicle screw instrumentation provides optimal biomechanical stability with fusion rates up to 95% 2
• Combined anterior-posterior approaches (ALIF with posterior instrumentation) achieve superior stability but carry higher complication rates (31-40%) 2
• Complication rates for TLIF procedures are approximately 33.6%, including cage subsidence, new nerve root pain, and hardware issues 2

Expected Outcomes with Surgery

• Clinical improvement occurs in 86-92% of appropriately selected patients 2
• Statistically significant reductions in both back pain (p=0.01) and leg pain (p=0.002) compared to decompression alone when spondylolisthesis is present 2
• Resolution of radiculopathy occurs in the majority of cases when preoperative radicular symptoms are present 2

Critical Pitfalls to Avoid

Do not proceed to surgery without completing adequate conservative management. 2 The lack of formal physical therapy completion is a critical deficiency that must be addressed first 2.

Do not assume imaging findings correlate with symptoms. 3, 4 Disc abnormalities and mild retrolisthesis are common in asymptomatic individuals and may not be the pain source 3, 4.

Do not fuse based on imaging alone without documented instability. 2, 5 Slight retrolisthesis without dynamic instability on flexion-extension films does not automatically warrant fusion 2.

Avoid early imaging without red flags, as this leads to increased healthcare utilization and unnecessary interventions 3.

Monitoring and Follow-up

• Reassess at 6 weeks after initiating conservative treatment to determine response 3
• Obtain flexion-extension radiographs if considering surgery to document dynamic instability 2
• MRI without contrast is the preferred imaging modality if symptoms persist beyond 6 weeks and surgical intervention is being considered 3
• Postoperative CT with fine-cut axial and multiplanar reconstruction is superior to plain radiographs for assessing fusion status if surgery is performed 2