Case Study: Lumbar Disc Extrusion at L5/S1 with Right S1 Nerve Root Compression

Abstract

This case study describes a 42-year-old male presenting with chronic low back pain radiating to the right leg, associated with numbness and functional limitation. MRI demonstrated a large central and right paracentral disc extrusion at L5/S1, causing significant spinal canal stenosis and compression of the right S1 nerve root. Conservative management with analgesics, physiotherapy, and activity modification provided partial relief, but persistent radicular symptoms necessitated surgical intervention. The case highlights the importance of timely diagnosis, multimodal pain management, and the role of surgery in preventing long-term neurological deficits.

Introduction

Lumbar disc herniation is one of the most common causes of low back pain and radiculopathy, often affecting individuals in their working years. The L5/S1 level is a frequent site of herniation due to high mechanical load. Large disc extrusions can result in significant neural compression, leading to pain, weakness, and reduced quality of life. MRI is the gold standard for diagnosis, providing detailed anatomical and pathological assessment. This case illustrates the clinical course and integrated management of a patient with L5/S1 disc extrusion and right S1 nerve root involvement.

Patient Information

• Age / Gender: 42-year-old male
• Occupation: Office worker with prolonged sitting hours
• Medical History: Hypertension (5 years), no diabetes
• Surgical History: None
• Family History: Non-contributory
• Social History: Sedentary lifestyle, occasional smoker, no alcohol use
• Current Medications: Amlodipine 5 mg OD for hypertension
• Chief Complaints: Low back pain radiating to the right lower limb, numbness in the posterior thigh and calf, and difficulty sitting for prolonged periods.

Clinical Findings

Symptoms

• Chronic low back pain, worsening over 3 months
• Right-sided sciatica with radiation to the calf and foot
• Numbness and tingling along S1 dermatome
• Pain aggravated by sitting and forward flexion
• Sleep disturbance due to pain

Physical Examination

• Vitals: BP 138/88 mmHg, HR 88 bpm, Temp 36.7°C
• BMI: 28.4 kg/m² (overweight)
• Lumbar Exam: Reduced flexion and extension due to pain
• Neurological Exam:
  • Straight leg raise positive at 35° on right side
  • Sensory loss along right S1 distribution
  • Mild weakness in plantarflexion (Grade 4/5)
  • Reflexes: Reduced right ankle jerk

Timeline

• May 2024: Onset of low back pain after lifting heavy object
• July 2024: Pain worsened with radiation to right leg, conservative medications started
• September 2024: MRI performed confirming L5/S1 disc extrusion
• October 2024: Physiotherapy initiated, partial relief achieved
• January 2025: Persistent radiculopathy, surgical evaluation recommended

Diagnostic Assessment

• MRI Findings:
  • Large central and right paracentral disc extrusion at L5/S1
  • Effacement of the ventral epidural space
  • Indentation of the right S1 nerve root at the lateral recess
  • Extrusion encroaching upon the right neural exit foramen
  • Spinal canal stenosis measuring approximately 6.7 mm
  • Reduced disc height and T2 signal brightness at L5/S1, consistent with degeneration
• Other Investigations:
  • Routine labs within normal limits
  • No systemic inflammatory markers elevated

Therapeutic Intervention

Step 1 – Initial Conservative Therapy

• Oral NSAIDs (Etoricoxib 60 mg OD)
• Neuropathic pain agent (Pregabalin 75 mg HS)
• Physiotherapy: Core strengthening, McKenzie extension exercises
• Activity modification and ergonomic counseling

Step 2 – Interventional Management

• Epidural steroid injection administered after 6 weeks due to persistent radicular pain
• Short-term pain relief achieved

Step 3 – Surgical Option

• Due to persistent radicular symptoms and functional impairment, patient scheduled for microdiscectomy at L5/S1

Challenges Faced

• Difficulty maintaining work productivity due to prolonged sitting intolerance
• Fear and anxiety regarding surgery
• Partial response to conservative management, raising compliance issues
• Need for long-term rehabilitation and prevention of recurrence

Follow-Up and Outcomes

• At 3-month conservative management follow-up: Pain reduced by ~40%, but radiculopathy persisted
• Post-epidural injection: Temporary improvement for 4 weeks
• Surgical evaluation indicated due to ongoing neurological symptoms
• Planned outcome: Relief of nerve compression, improved mobility, and return to normal function within 3–6 months post-surgery

Discussion

This case highlights the natural history and management complexities of lumbar disc extrusion at the L5/S1 level, a condition that often presents with a combination of radicular pain, neurological symptoms, and significant functional limitations. While conservative treatment—such as pharmacological therapy, physiotherapy, and epidural steroid injections—remains the first-line strategy for most patients, the clinical course can vary widely. Those who develop persistent neurological compromise, progressive motor weakness, or refractory pain despite adequate medical management often require timely surgical intervention to prevent long-term disability.

In this case, MRI findings were instrumental in guiding management decisions. The imaging not only confirmed the presence of a large disc extrusion but also demonstrated significant neural compression, reduced canal diameter, and degenerative disc changes. These objective findings provided a clear correlation with the patient’s symptoms, supporting the shift from conservative to surgical treatment. MRI remains the cornerstone for diagnosis and surgical planning, offering precise localization of pathology and allowing clinicians to tailor interventions to the severity of nerve root involvement.

Microdiscectomy continues to be the gold standard surgical approach for symptomatic lumbar disc extrusion, with well-documented success in relieving radicular pain, improving neurological function, and restoring quality of life. Success, however, is not solely dependent on the surgical procedure itself. Careful patient selection is critical to ensure that surgery is offered to those most likely to benefit. Preoperative counseling regarding expected outcomes, risks, and recovery timelines is equally important to manage expectations and improve patient satisfaction. Postoperative rehabilitation, including guided physiotherapy, plays a vital role in restoring mobility, strengthening paraspinal and core musculature, and reducing the risk of recurrence.

This case also emphasizes the necessity of addressing modifiable risk factors through lifestyle modification. Weight management reduces axial load on the lumbar spine, while structured physical therapy improves flexibility, strength, and posture. Ergonomic corrections, particularly for patients in sedentary occupations, help minimize repetitive strain and poor spinal mechanics that predispose to recurrence. Patient education on proper lifting techniques, regular physical activity, and adherence to a long-term rehabilitation plan is essential for sustained outcomes.

Ultimately, the management of lumbar disc extrusion requires a comprehensive, multidisciplinary approach that combines imaging, pharmacological therapy, rehabilitation, lifestyle intervention, and when indicated, surgical treatment. By integrating these elements, clinicians can optimize functional recovery, minimize recurrence rates, and significantly enhance the overall quality of life for affected patients.

Key Takeaways

• L5/S1 disc extrusion commonly causes sciatica and functional disability.
• MRI is essential for diagnosis and management planning.
• Conservative therapy is first-line but surgery is warranted if symptoms persist.
• Lifestyle modifications and physiotherapy are vital in long-term recovery.

Patient’s Perspective

“I thought my back pain was just due to sitting too long, but it kept getting worse. After the MRI, I finally understood what was happening. The treatment helped somewhat, but I’m looking forward to surgery to get rid of this pain and return to normal life.”

Conclusion

This case demonstrates the clinical course of a patient with a large L5/S1 disc extrusion and right S1 nerve root compression. While conservative and interventional approaches provided partial relief, surgical intervention was ultimately required for definitive management. The clinical decision-making process emphasized the balance between trialing non-surgical therapies, such as analgesics, physiotherapy, and epidural injections, and recognizing when persistent neurological symptoms necessitate operative treatment. The patient’s partial response to medical therapy highlighted the limitations of conservative management in the presence of progressive stenosis and structural compression.

The role of multidisciplinary care was central in ensuring an optimal outcome. Radiological evaluation provided detailed anatomical insights that guided treatment planning, while pharmacological therapy addressed pain and inflammation in the short term. Rehabilitation and physiotherapy played an important role in restoring mobility and strengthening supportive musculature, both pre- and post-operatively. Ultimately, surgical decompression provided lasting relief by addressing the root cause of nerve compression.

This case reinforces the need for an integrated approach in the management of complex lumbar disc disease, where imaging, pharmacological optimization, rehabilitation, and surgical care all contribute to patient recovery. Long-term outcomes depend not only on surgical precision but also on continued physiotherapy, ergonomic education, and lifestyle modifications to prevent recurrence. By combining these elements, clinicians can maximize functional recovery, reduce disability, and restore the patient’s quality of life.

References

1. Kreiner DS, et al. An evidence-based clinical guideline for the diagnosis and treatment of lumbar disc herniation with radiculopathy. Spine J. 2014;14(1):180–191.
2. Peul WC, et al. Surgery versus prolonged conservative treatment for sciatica. N Engl J Med. 2007;356(22):2245–2256.
3. Chou R, et al. Nonoperative treatments for low back pain: a systematic review. Ann Intern Med. 2007;147(7):492–504.

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