Diseases of the Spinal Cord

1. Diseases of the Spinal Cord

2. Disease description • Many conditions constitute neurologic emergencies because of • Severity on presentation (quadriplegia, sensory deficits, spinal shock) • Potential reversibility • Hallmark: presence of horizontally defined level below which motor, sensory and autonomic function is impaired

3. Approach to a Patient • Determine level of lesion • Identify special anatomic patterns, if any • Determine time frame of the disease • Differentiate compressive from non-compessive lesions

4. Determining level of the lesion • Sensory level • Using pinprick or cold stimulus • Level indicates damage to the spinothalamic tract 1-2 segments above a unilateral lesion or at the level of the bilateral lesion

5. Determining level of the lesion • Motor level • Damage to the descending corticospinal tract • Paraplegia or quadriplegia • Upper motor neuron syndrome • Autonomic abnormalities • Sweating • Bladder or bowel dysfunction

6. Determining level of lesion

7. Determining level of the lesion • Upper level of the lesion may be determined with segmental signs • Hyperalgesia or hyperpathia • Fasciculations or muscle atrophy • Hypo- or areflexia

8. Special patterns

9. Special patterns • Brown-Sequard syndrome • Ipsilateral weakness (corticospinal), loss of joint and position sense (posterior column) • Contralateral loss of pain or temperature sense 1-2 levels below the lesion (spinothalamic) • Unilateral segmental signs

10. Special patterns • Central cord syndrome • Damge to gray matter and crossing spinothalamic tracts near central canal • Arm > leg weakness • Loss of pain and temperature sense with intact light touch, joint position and vibration sense (dissociated sensory loss)

11. Special patterns • Anterior spinal artery syndrome • Extensive bilateral deficits below the level of the lesion, with intact vibration and position sense • Foramen magnum syndrome • Damage to decussating pyramidal tract fibers of the legs • “Around the clock” pattern of weakness with suboccipital pain

12. Special patterns • Extramedullary • Radicular pain • Early sacral sensory loss, spastic leg weakness • Intramedullary • Sacral sparing

13. Time-frame of the disease • Acute or severe transverse lesions may initially present as spinal shock (flaccidity, areflexia) in the first few days or weeks, rather than upper motor neuron signs • May be mistaken for acute severe polyneuropathy or stratified to have more severe damage than actual

14. Compressive vs noncompressive myelopathy Compressive (mass) • Tumor • Epidural abscess or hematoma • Herniated disc • Vertebral pathology Non-compressive (intrinsic cord lesions) • Vascular • Inflammatory • Infectious

15. Tumors • Extradural • Intradural • Intramedullary • Epidural abscess • Epidural hematoma Compressive myelopathies

16. Neoplastic spinal cord compression: Epidural neoplasms • Mostly metastatic (breast, lung, prostate, kidney, lymphoma, myeloma) • Thoracic cord most common except for prostate and ovarian cancers (lumbosacral) • Pain is an early symptom, awakens patient at night and is worse with movement • MRI is useful

17. Neoplastic spinal cord compression: Epidural • Therapy • Glucocorticoids • Local radiotherapy • Treatment of underlying tumor • Fixed motor deficits of >12 hours do not usually improve and > 48 hours, prognosis is poor

18. Neoplastic spinal cord compression: Intradural • Mostly slow-growing and benign • Meningiomas, neurofibromas, also chordoma, lipoma, dermoid, sarcoma • Present with radicular sensory symptoms followed by asymmetric progressive cord syndrome • Therapy is surgical resection

19. Neoplastic spinal cord compression: Intramedullary • Present as central cord or hemicord syndromes of the cervical region • Ependymoma, hemangioblastoma or low-grade astrocytoma in adults • Secondary metastatic lesions are also common

20. Spinal epidural abscess • Triad: • midline dorsal pain, fever, progressive limb weakness • Risk factors: • impaired immune status, intravenous drug abuse, infections of skin or otehr tissues • Causes: • Hematogenous spread • Direct extension

21. Spinal epidural abscess • Causative organsims • Staph. Aureus • Tuberculosis • Gram-neg bacilli, Strep, anaerobes, fungi • Lab tests • MRI • High cervical MRI (to rule out concomittant meningitis) • Blood culture

22. Spinal epidural abscess • Treatment • Decompressive laminectomy with debridement with • Empirical, then culture-guided, antibiotics for >4weeks

23. Spinal epidural hematoma • Acute focal or radicular pain with variable cord findings • Risk factors: anticoagulation, trauma, tumor or blood dyscrasia • Labs • MRI, CT • Therapy is surgical decompression and correction of underlying problem

24. Spinal cord infarction • Inflammatory and immune myelitis • Systemic inflammatory diseases • SLE • Demyelinating myelopathy • Multiple sclerosis • Post-infectious myelitis • Acute infectious myelitis Noncompressive myelopathies

25. Spinal cord infarction • “Watershed” infarcts • T3-T4 and boundary zones between anterior and posterior spinal artery territories • Rapidly progressive weakness and spasticity with little sensory change • Usually associated with hypotension

26. Spinal cord infarction • Anterior spinal artery infarct • Anterior cord syndrome • Paraplegia or quadriplegia, dissociated sensory loss, loss of sphincter control • Onset may be sudden or progressive over hours • Sharp midline back pain • Initial spinal shock

27. Systemic inflammatory disorders • Mostly due to SLE, specially with antiphopholipid antibodies • CSF may be normal or show mild lymphocytic pleocytosis • May respond to high dose steroids and cyclophosphamide

28. Demyelinating myelopathy • Multiple sclerosis may present as myelitis • Mild swelling and edema of the cord • Multifocal areas of abnormal T2 signal on MRI • Mild pleocytosis, oligoclonal band • Hihg dose steroids, plasma exchange • Neuromyelitis optica • No oligoclonal bands • May respond to anti-CD20 (rituximab)

29. Post-infectious or post-vaccinal myelitis • Organisms implicated: EBV, CMV, mycoplasma, influenza, measles, varicella, rubeola, mumps • Autoimmune disorder triggered by infection and not due to direct infection of spinal cord • Treatment glucocorticoids,plasma exchange

30. Acute infectious myelitis • Poliomyelitis, herpes zoster • Bacterial or mycobacterial myelitis (abscess) • Schistosomiasis

31. Spondylitic myelopathy • Vascular malformations of the cord and dura • Syringomyelia • Subacute combined degeneration • Tabes dorsalis • Familial spastic paraplegia Chronic myelopathies

32. Spondylitic myelopathy • Most common cause of gait problems in the elderly • Early neck and shoulder stiffness, later radicular pain • Cord compression in <1/3 of patients • Spastic paraparesis, paresthesia • Reduced vibratory sense, (+) Romberg sgin • Dermatomal sensory loss & decreased tendon reflex in the arms, intrinsic hand muscle atrophy • Hyperreflexia in the legs

33. Vascular malformation of the cord & dura • Slowly progressive or intermittent myelopathy with incomplete sensory, motor or bladder disturbance • Spinal bruits • Labs : high resolution contrast MRI, CT myelogram, selective spinal angiography • Therapy: endovascular embolization

34. Syringomyelia • Developmental cavitary expansion of the cervical cord, often associated with Chiari type I malformation • Classic presentation is central cord syndrome (dissociated sensory loss, areflexi weakness of the arms) • Symptoms progress as the syrinx expand

35. Subacute combined degeneration • Vitamin B12 deficiency • Subacute paresthesia in hands & feet, loss of vibration and position sense, progressive spastic & ataxic weakness • Diffuse, symmetric myelopathy • Predominant involvement of posterior and lateral tracts • Associated peripheral neuropathy

36. Subacute combined degeneration • Labs: macrocytic RBCs, low B12 concentration • Therapy: replacement with intramuscular 1000ug vitamin B12 at regular intervals or subsequent oral treatement

37. Tabes dorsalis • Complication of syphilis • Fleeting and lancinating pains in the legs, wtih ataxia due to loss of position sense • Loss of leg reflexes • Impaired vibratory and position sense • Romberg’s sign • Argyll Robertson pupils • Differential: diabetic polyradiculopathy

38. Familial spastic paraplegia • Genetic defects of >20 different loci presenting as slowly progressive myelopathy • Progressive spasticity and leg weakness • Absent or mild sensory symptoms • Sphincter disturbances • + nystagmus, ataxia, optic atrophy • Onset maybe from infancy to middle adulthood • Therapy: symptomatic for spasticity

39. Summary • Spinal cord conditions may present catastrophically but many have treatable causes • Determine the level of the lesion and identify special patterns in the presentation to derive a diagnosis • Address the conditions promptly

40. Thank you.