What is the recommended evaluation and treatment plan for a patient with a disc protrusion?

Evaluation and Treatment of Disc Protrusions

MRI of the lumbar spine without contrast is the neuroimaging study of choice for evaluating disc protrusions, and most patients should be managed conservatively without surgery unless they present with red-flag neurological symptoms requiring urgent intervention. 1

Initial Evaluation

Clinical Assessment Priority

• Identify red-flag symptoms immediately: unilateral whole-body sensory changes, progressive neurological deficits developing over 2 days, multifocal neurological involvement, or signs of cauda equina syndrome (bladder/bowel dysfunction, saddle anesthesia) 2
• Distinguish radiculopathy patterns: single nerve root involvement (typical disc protrusion) versus hemibody changes (suggests pathology above lumbar level) 2
• Document baseline neurological function: motor strength, sensory distribution, reflexes, and straight leg raise testing to track progression 3

Imaging Strategy

For typical low back pain with radiculopathy:

• Order lumbar MRI without IV contrast as first-line imaging 1
• MRI demonstrates 99% accuracy in detecting disc abnormalities and avoids the expense and invasiveness of discography 1
• The positive predictive value of abnormal MRI for morphologically abnormal disc is 92%, with negative predictive value of 88% 1

For red-flag presentations:

• Order urgent whole-spine MRI (cervical, thoracic, and lumbar) without contrast 2
• Do not limit imaging to lumbar spine alone when symptoms suggest higher-level pathology 2
• Obtain imaging within hours, not days, as delayed diagnosis significantly worsens neurological outcomes 2

Critical Pitfall to Avoid

Do not attribute new hemibody sensory changes or rapidly progressive symptoms to an incidental lumbar disc bulge—disc bulges are extremely common incidental findings (present in asymptomatic individuals) and rarely produce extensive neurological symptoms 2, 4. MRI studies show no significant difference between disc protrusions, bulges, and discs with normal contour regarding internal architecture or symptomatic tears 4.

Treatment Algorithm

Conservative Management (First-Line for Most Patients)

Indications:

• Isolated low back pain with or without single-level radiculopathy 1
• No progressive neurological deficits 2
• No cauda equina syndrome features 2

Treatment approach:

• Active spinal manipulation by experienced chiropractors shows superior pain relief compared to simulated manipulation (28% vs 6% pain-free for local pain; 55% vs 20% for radiating pain) 3
• Manipulations reduce mean days with pain (23.6 vs 27.4 days) and days with moderate-severe pain (13.9 vs 17.9 days) 3
• Treatment typically involves 5 sessions per week, up to maximum of 20 sessions 3

Surgical Intervention

Absolute indications requiring surgery within 12-24 hours:

• Cauda equina syndrome with incomplete bladder function (CESI stage): 90-100% chance of regaining normal bladder function if treated urgently, versus only 48-93% if delayed to retention stage 2
• Spinal cord compression confirmed on MRI: surgical decompression within 12-24 hours yields best neurological recovery (odds ratio ≈ 2.83 for improved prognosis) 2
• Progressive motor weakness over 2-day period 2

Relative indications for elective surgery:

• Recurrent disc herniation with degenerative changes and persistent low back pain despite conservative therapy 1
• Displacement-type lumbar disc protrusion (Lee regions I-IV) with failed conservative management 5

Surgical technique selection:

• Percutaneous endoscopic interlaminar discectomy (PEID) for displacement-type protrusions at L2-L5: operative time 45-90 minutes, hospitalization 3-4 days, excellent-to-good results in 93% of patients 5
• Complete removal of herniated disc fragments for damage-herniation type (soft herniation caused by injury); minimally invasive endoscopic surgery achieves satisfactory results 6
• Posterior decompression with minimal disc removal for degeneration-protrusion type (hard, tough protrusions); focus on nerve decompression rather than disc excision 6

Primary fusion is seldom indicated for simple disc herniation 1. Fusion should be reserved for patients with concurrent degenerative spondylolisthesis or documented instability 1.

Pathological Classification Considerations

Understanding disc pathology guides surgical approach 6:

• Damage-herniation type: soft, easily removed; requires complete fragment removal 6
• Degeneration-protrusion type: hard, tough; requires nerve decompression, not aggressive disc removal 6
• Posterior vertebral osteochondrosis: requires removal of herniated disc plus protruding osteochondral nodules 6
• Intervertebral disc cyst: resect cyst under microscopic/endoscopic control 6

Time-Critical Decision Points

Within 2 days of symptom onset:

• This window still allows intervention to prevent permanent disability 2
• Do not postpone imaging for conservative trial when red flags present 2
• Do not wait for bladder/bowel dysfunction to develop—irreversible damage may already have occurred 2

Arrange immediate neurosurgical consultation if MRI confirms:

• Spinal cord compression 2
• Significant nerve root compression with progressive deficits 2
• Cauda equina syndrome 2