Case Study: Degenerative Spinal Disorders

Degenerative Spinal Disorders: Case Study

Case Presentation

Mr. B. is a 55-year-old male who presents with a history of chronic low back pain that has recently worsened and started radiating down his right leg. He reports that the pain is aggravated by coughing and sneezing and finds some relief by slightly bending forward at the waist. He notes difficulty walking long distances due to increasing pain and weakness in his leg, which he describes as a dull ache and sometimes a tingling sensation. Mr. B. has a history of working in a physically demanding job involving heavy lifting.

On physical examination, there is restricted movement in his lumbar spine, local tenderness over the lower back, and some paravertebral muscle spasm. Straight Leg Raising Test (SLRT) on the right side is positive at 45 degrees, eliciting his radicular pain. Motor examination reveals mild weakness in dorsiflexion of the right foot. Sensation is slightly diminished in the distribution of the right L5 dermatome. Deep tendon reflexes are symmetric. An MRI of the lumbar spine is performed.

Questions

1. Based on the location of symptoms (low back and leg), which major division of the nervous system and which specific part of the CNS are primarily involved in degenerative spinal disorders?
2. The patient's symptoms point towards "Degenerative spinal disorders". What are the specific conditions within this category mentioned in the source that could explain low back and leg pain with neurological symptoms? Briefly mention the difference between radiculopathy and myelopathy in the context of degenerative spinal disorders, as described for both cervical and lumbar regions.
3. Explain the likely pathophysiological mechanism causing the patient's symptoms, including how disc herniation leads to root compression and why coughing/sneezing might aggravate the pain, referencing the relevant structures.
4. Describe the characteristic clinical signs on physical examination for lumbar disc prolapse as mentioned in the source, including back signs and specific nerve root tension tests. What does a positive Straight Leg Raising Test (SLRT) indicate?
5. The MRI shows a posterolateral disc herniation. Describe the grades of disc herniation mentioned in the source. If this posterolateral herniation compresses a nerve root, which level is commonly affected in lumbar disc prolapse?
6. Outline the conservative management options for lumbar disc prolapse detailed in the source.
7. What are the indications for surgical treatment in lumbar disc prolapse according to the source, and what surgical procedures are listed?
8. If the patient developed sudden, severe back and leg pain, profound weakness in the lower extremities (described as LMN), numbness in the "saddle area," and inability to urinate, what specific emergent condition, related to lumbar degenerative disorders, should be suspected based on the source? What is the required management for this condition?

Answers

1. Based on the location of symptoms in the low back and leg, the Central Nervous System (CNS), specifically the spinal cord, and potentially the Peripheral Nervous System (via the nerve roots exiting the spinal cord) are primarily involved. Degenerative spinal disorders affect the spine, which encloses and protects the spinal cord.

2. Within the category of "Degenerative spinal disorders," the specific conditions that could explain low back and leg pain with neurological symptoms include Lumbar disc prolapse and lumbar canal stenosis (lumbar spondylosis). Degenerative spine conditions involve the loss of strength, function, or mobility of the spine due to changes in structures like vertebral bodies, intervertebral discs, facet joints, and ligaments. These can lead to compression of nerve roots (radiculopathy) or the spinal cord (myelopathy).

   In the cervical region, disc prolapse or spondylosis can cause Radiculopathy (root compression) and/or Myelopathy (cord compression), or both (Radiculomyelopathy). Similarly, in the lumbar region, disc prolapse usually causes Radiculopathy (root compression), leading to Sciatica if lower roots are compressed, while significant central compression or lumbar canal stenosis can cause Cauda Equina Syndrome or Neurogenic claudication, which affect multiple roots or the distal spinal cord segments.

3. The likely pathophysiological mechanism involves the intervertebral disc located between the bony vertebrae. The disc has a fibrous outer wall (annulus fibrosus) surrounding a jelly-like core (nucleus pulposus). Degenerative changes or injury can weaken the annulus fibrosus, allowing the nucleus pulposus to herniate (disc prolapse). When the prolapse is posterolateral, it can compress an exiting spinal nerve root. Compression or irritation of the nerve root causes the radiating pain (radiculopathy) and neurological symptoms in the leg. Coughing, sneezing, and straining increase pressure within the spinal canal, which can exacerbate the compression on the affected nerve root, thus aggravating the pain.

4. Characteristic clinical signs of lumbar disc prolapse on physical examination include back signs such as Restricted spinal movement, Local tenderness, Scoliotic tilt, Paravertebral muscle spasm, and Obliteration of lumbar lordosis. Nerve root tension signs are also important.

   The Straight Leg Raising Test (SLRT) is a clinical test performed by passively elevating the fully extended leg. It is considered positive if the patient feels sciatica at an angle <60°. A positive SLRT is indicative of lower disc prolapse (L5 and S1 root irritation). Another test mentioned is the Femoral stretch test (reverse SLRT), which is positive in higher disc prolapse (L2, L3, or L4 root irritation).

5. The source describes several grades of disc herniation beyond a simple bulge: Protrusion, Extrusion, Sequestration, and Migration. A posterolateral disc herniation causing root compression, as in this case, could correspond to a Protrusion, Extrusion, or Sequestration grade depending on the extent.

   In lumbar disc prolapse, the levels most commonly affected are L4-L5 and L5-S1, which typically compress the L4, L5, or S1 nerve roots.

6. Conservative management options for lumbar disc prolapse detailed in the source include: Rest, lifestyle modification and reduction of body weight, Lumbar support, Physiotherapy, Analgesics (e.g., NSAIDs), Antineuropathic pain medications (e.g., Gabapentin), Muscle relaxants, and Epidural steroid injections.

7. According to the source, the indications for surgical treatment in lumbar disc prolapse are: Radiculopathic pain not responding to medical treatment and Progressive neurological deficit due to root compression. The source also lists manifestations of Cauda equina syndrome as an indication for urgent surgery.

   Surgical procedures mentioned include: Standard open laminectomy and discectomy, Microdiscectomy, Endoscopic discectomy, and Wide laminectomy (± facetectomy) with or without instrumentation.

8. If the patient developed sudden, severe back and leg pain, profound weakness in the lower extremities (described as LMN - Lower Motor Neuron type), numbness in the "saddle area," and inability to urinate, the emergent condition suspected, related to lumbar degenerative disorders (specifically a large central disc prolapse), is Cauda Equina Syndrome.

   The source states that manifestations of Cauda equina syndrome are an indication for urgent surgery. The clinical features mentioned correspond to the description of Cauda equina syndrome symptoms: incapacitating back and lower extremity pain, numbness including saddle anesthesia/hypoesthesia, profound LMN weakness/hyporeflexia of the lower extremities, inability to urinate (early) and urinary incontinence (later), bowel issues, and sexual dysfunction.