From the Guidelines
Disc prolapse is a condition where the nucleus pulposus herniates through a weakened or torn annulus fibrosus of an intervertebral disc, and it can be classified based on its location as central, paracentral, or lateral, each with distinct symptom patterns and treatment approaches. A central disc prolapse occurs when the disc material herniates directly backward into the spinal canal, potentially compressing the spinal cord in the cervical or thoracic regions or the cauda equina in the lumbar region, and may cause myelopathy or cauda equina syndrome in severe cases 1. Paracentral disc prolapse occurs when the herniation is slightly off-center, often compressing the traversing nerve root as it descends in the spinal canal, and presents with unilateral radicular symptoms. Lateral disc prolapse, also called foraminal herniation, occurs when the disc material protrudes into the intervertebral foramen, compressing the exiting nerve root at that level.
The clinical significance of these different types lies in their distinct symptom patterns and treatment approaches. Central herniations may require more urgent intervention if they cause cord compression or cauda equina syndrome (urinary retention, saddle anesthesia, bilateral leg weakness) 1. Paracentral and lateral herniations typically cause radicular pain, sensory changes, and motor weakness in the distribution of the affected nerve root. Treatment generally begins conservatively with pain management, physical therapy, and possibly epidural steroid injections, progressing to surgical intervention (discectomy or microdiscectomy) if symptoms are severe, progressive, or unresponsive to conservative measures 1.
Some key points to consider in the management of disc prolapse include:
- The natural history of lumbar disc herniation with radiculopathy in most patients is for improvement within the first 4 weeks with noninvasive management 1
- There is no compelling evidence that routine imaging affects treatment decisions or improves outcomes 1
- Magnetic resonance imaging (preferred if available) or CT is recommended for evaluating patients with persistent back and leg pain who are potential candidates for invasive interventions 1
- Clinicians should provide patients with evidence-based information on low back pain with regard to their expected course, advise patients to remain active, and provide information about effective self-care options 1
In summary, the management of disc prolapse should be based on the clinical correlation between symptoms and radiographic findings, severity of symptoms, patient preferences, surgical risks, and costs, and will generally require specialist input.
From the Research
Definition of Central, Paracentral, and Lateral Disc Prolapse
- Central disc prolapse: occurs when the disc material protrudes into the central canal of the spine, potentially compressing the spinal cord or cauda equina 2
- Paracentral disc prolapse: occurs when the disc material protrudes into the paracentral region, which is the area between the central canal and the lateral recess of the spine, potentially compressing the nerve roots 2
- Lateral disc prolapse: occurs when the disc material protrudes into the lateral recess or the intervertebral foramen, potentially compressing the nerve roots as they exit the spine 2
Clinical Significance
- The clinical significance of disc prolapse depends on the location and size of the prolapse, as well as the presence of neural compression or irritation 2
- Central and paracentral disc prolapses are more likely to cause symptoms such as back pain, leg pain, and neurological deficits, while lateral disc prolapses may cause more localized symptoms such as radiculopathy or sciatica 2
- The presence of neural foramen compromise is more important in determining the clinical signs and symptoms of disc prolapse than the type of disc herniation (bulge, protrusion, or extrusion) 2
- Surgical discectomy for carefully selected patients with sciatica due to lumbar disc prolapse provides faster relief from the acute attack than conservative management, although any positive or negative effects on the lifetime natural history of the underlying disc disease are still unclear 3