NeuroSurgery Case: Low Back Pain

1. NeuroSurgery Case:Low Back Pain

2. Salient Features • A 45 year old office secretary • Sudden snap and pain in the left lumbar area while trying to lift a box load of papers. • Pain was subsequently felt in the posterolateral aspect of the right thigh and leg down to the right heel. • Admitted initially and placed on bed rest and pelvic traction for 3 weeks with no improvement.

3. Neurological examination revealed the following findings: • BP: 130/80, PR: 88, RR: 18, T: 37 • Patient in left lateral decubitus with the right knee flexed • Numbness in the back of the right calf muscle, lateral heel, foot and toe • Weakness of the right plantar flexion of foot and toes • Difficulty walking on toes on the right • Atrophy of right gastrocnemius and soleus muscles • Both knee jerks are (++) • Right ankle jerk absent, left ankle jerk is (++) • No babinski bilaterally • The rest of the neurological examination is within normal limit

4. 1. What is the nature of the problem of the patient? What is the anatomical explanation of the symptoms of the patient?

5. Nature of the problem • Based on the history of the patient (heavy lifting, while bent at the waist), the most probable problem is due to an injury to the spinal cord, more specifically, a lumbar disc herniation. • A tear in an annulus fibrosus allows the nucleus pulposus to squeeze into the spinal canal. If a nerve root is compressed by the disc material, there can be pain, numbness, and weakness in the areas supplied by the nerve (often down the back of a leg).

7. Depending on the nerve root that is compressed, the patient may present with the following symptoms:

9. Anatomic Problem • Right L5-S1 nerve root compression due to lumbar disc herniation • Lumbar Radiculopathy (affecting L5-S1) • If a nerve root is compressed by the disc material, there can be pain, numbness, and weakness in the areas supplied by the nerve

10. 2. What is the difference between a radicular and a myelopathic manifestations and what is the significance of each in relation to the signs and symptoms and clinical management?

11. Radiculopathy vs Myelopathy • when a disc or osteophytic protrusion compresses the adjacent nerve roots = radiculopathy • when a disc or osteophytic protrusion compresses the spinal cord = myelopathy

12. Radiculopathy • pain + paresthesia + root signs • Pain = (sharp, stabbing, worse on coughing) + (constant deep ache radiating over shoulders and down the arm) : follows a nerve root distribution • Paresthesia: numbness or tingling follows a nerve root distribution

13. Radiculopathy • Root signs: • sensory loss—pin prick deficit in the appropriate dermatomal distribution • muscle (lower motor neuron) weakness and wasting in appropriate muscle groups • reflex impairment or loss • trophic change—in long standing root compression, skin becomes dry, scaly, inelastic, blue, and cold

14. Myelopathy • Compression causes segmental damage at the involved level and long tract signs below level • Arms: LMN signs and symptoms; UMN signs and symptoms below the level of the lesion (e.g. muscle weakness and wasting, diminished reflexes in some joints, hyperreflexia in others, all corresponding to the nerve distribution)

15. Myelopathy • Legs: UMN signs and symptoms; difficulty in walking due to stiffness; “pyramidal” distribution weakness, increased tone, clonus and extensor plantar responses; sensory symptoms and signs are variable and less prominent • Sphincter disturbance is seldom a prominent early feature