II. Definitions
- Myelopathy
- Spinal Cord Injury and compression resulting in UMN and LMN neurologic deficits
- Cervical Myelopathy
- Cervical Spinal Cord Injury and compression with neurologic deficits (most commonly due to degenerative disease)
III. Epidemiology
- Cervical Spondylotic Myelopathy is the most common spinal cord disorder in adults
- Onset age 50-60 years (mean presenting age 64 years old)
- Prevalence: 605 per 1 Million (U.S.)
- Gender: Male (by 3:1 ratio)
IV. Pathophysiology
- Spinal cord compressed by degeneration (discs and facets) as well as ligamentous hypertrophy and ossification
- Includes hard disc lesions with Cervical Spondylosis (chronic) in older patients
- Pressure of posterior osteophytes at anterior cord
- Results in combined nerve root (Lower Motor Neuron) and cord compression (Upper Motor Neuron) symptoms
- Lower extremities are typically more affected than lower extremities
- Lower extremity tracts are more peripheral in cord and susceptible to injury than upper extremity tracts
- Lateral spinal cord tracts are more susceptible to initial injury
- Spinothalamic Tract (pain and TemperatureSensation) and Lateral Corticospinal tract (motor) are susceptible to injury
- Dorsal columns (ipsilateral vibration and proprioception) are less affected in the posterior cord
- Distribution
- C5-6 (most common)
- C6-7 and C4-5 are also common
V. Risk Factors: Degenerative Cervical Spine Findings
- Static
- Congenital spinal stenosis
- Degenerative disc disease
- Ligamentum flavum ossification
- Posterior longitudinal ligament ossification
- Cervical Spondylosis
- Vertebral osteophytes
- Dynamic
- Degenerative Spondylolisthesis
- Spinal cord straining or Stretching from cervical flexion or extension
- Physiologic spinal canal narrowing
VI. Risk Factors: Noncompressive Factors (e.g. physiologic spinal canal narrowing)
- Cord Lesions
- Systemic Disease
- Alcohol Abuse
- Copper Deficiency
- Vitamin B12 Deficiency
- HIV Infection
- Liver Disease
- Paraneoplastic Syndrome
- Parkinsonism
- Viral Encephalitis
VII. Symptoms
- Cervical Nerve root related symptoms (radicular symptoms and Lower Motor Neuron Deficits at level of lesion)
- Neck Pain (50%)
- Neck stiffness
- Radicular symptoms such as Shoulder or arm pain, Paresthesias or numbness (38%)
- Upper extremity weakness or atrophy (corresponding to affected spinal level of compression)
- Spinal cord related symptoms (Upper Motor Neuron Deficits)
- Gait difficulty and falls
- Leg weakness and spasticity
- Ascending Paresthesias (first lower extremity, then upper extremity)
- Decreased hand dexterity and altered handwriting
- Autonomic Dysfunction
- Erectile Dysfunction
- Urine retention or stool retention (44%)
- Urine Incontinence or Stool Incontinence
VIII. Signs
- See Neck Exam
- Cervical Nerve root related signs (proximal lesion related and Lower Motor Neuron)
- Painful Cervical Spine range of motion
- Neck flexion stretches the spinal cord over Vertebral osteophytes
- Neck extension may force ligamentum flavum towards cord, narrowing spinal canal
- Lhermitte Sign
- Passive neck flexion results in electrical Sensation down spine or arms
- Upper extremity weakness (corresponding to affected spinal level of compression)
- Hyporeflexia (specific to affected nerve root)
- C6: Biceps Reflex and Brachioradialis Reflex
- C7: Triceps Reflex
- Painful Cervical Spine range of motion
- Spinal cord related symptoms (Upper Motor Neuron Deficits)
- Upper Motor Neuron Deficits
- Hyperreflexia
- Pathologic reflex spread
- Ankle Clonus
- Spasticity
- Babinski Reflex (or Brissaud Reflex)
- Intrinsic Hand Muscle atrophy and weakness
- Wide-based ataxic gait
- Romberg Test
- Hoffman Sign
- Flick the distal tip of the third or fourth finger
- Results in thumb abduction and flexion at the distal phalanx
- Synkinesis
- Involuntary limb movement occuring with voluntary other limb movement
- Pyramidal Weakness
- Flexion is stronger in the upper extremity
- Extension is stronger in the lower extremity
- Specific Findings for C5-6 Spinal Cord Compression
- Inverted Brachioradialis Reflex Positive (Supinator Test)
- Biceps Reflex Absent (C5)
- Brachioradialis Reflex (C6)
- Hyperreflexia at Triceps Reflex (C7)
- Upper Motor Neuron Deficits
IX. Differential Diagnosis
- Compressive Myelopathy
- Inflammatory or Autoimmune Myelopathy
- Rheumatoid Arthritis
- Multiple Sclerosis
- Amyotrophic Lateral Sclerosis
- Connective Tissue Disease (e.g. Systemic Lupus Erythematosus) or Vasculitis
- Acute infectious Myelitis (e.g. Herpes Zoster, HIV related Myelitis, Rabies)
- Spinal Osteomyelitis or Discitis (or Spinal Epidural Abscess as above)
- Post-infectious Myelitis
- Radiation Therapy
- Chronic Myelopathy
- Congenital Myelopathy
- Atlantoaxial Instability (esp. Down Syndrome, also seen in Congenital Dwarfism, odontoid hypoplasia)
- Klippel-Feil Syndrome
- Familial Spastic Paraplegia
- Adrenomyeloneuropathy
- Os Odontoideum
- References
X. Grading: Modified Japanese Orthopedic Association Scoring System of Cervical Myelopathy Severity (mJOA)
- Motor Scoring
- Score 0-4: Upper Extremity (unable to move hands=0, able to button shirt with slight difficulty=4)
- Score 0-7: Lower Extremity (complete motor loss=0, no dysfunction=7)
- Sensory Scoring
- Score 0-3: Upper Extremity (complete hand sense loss=0, no sensory loss=3)
- Score 0-3: Sphincter Dysfunction (unable to urinate voluntarily=0, normal urination=3)
- Interpretation (total of all 4 criteria from motor and sensory)
- Total >=15: Mild
- Total 12-14: Moderate
- Total <=11: Severe
- Resources
XI. Grading: Nurick Scoring of Cervical Myelopathy Severity
- Scoring (select one)
- Score 0: Root involvement symptoms and signs but NO spinal cord findings
- Score 1: Spinal cord findings but no difficulty with walking
- Score 2: Slight walking difficulty, but does not prevent full time employment
- Score 3: Able to walk without assistance, but walking difficulty limits full-time work and house work
- Score 4: Only able to walk with assistance or with use of walker or other similar device
- Score 5: Chairbound or bed bound
- Interpretation
- Score 0: Mild
- Score 1-2: Moderate
- Score >=3: Severe
XII. Imaging
- See Cervical Spine Imaging in Neck Pain
- MRI Cervical Spine with and without contrast
- CT Myelogram
- Alternative to MRI, when not available
- XRay Cervical Spine
- Consider while awaiting advanced imaging
- Defines spinal canal narrowing, osteophytes, ligament ossification
- Identifies significant cervical lordosis or kyphosis
XIII. Management
- Conservative Management
- See Cervical Disc Disease
- Physical Therapy
- Cervical Traction
- Risk of spinal ischemia complications
- Cervical Spine Immobilization
- Massage
- Foraminal injections or epidural steroid injections
- Surgical Management (Spinal cord decompression and stabilization)
- Indications
- Moderate to severe, or progressive Cervical Myelopathy
- Mild to moderate Cervical Myelopathy refractory to conservative management
- Contraindications
- Asymptomatic cord compression incidental on imaging (surgery NOT recommended)
- Cervical stenosis is a common finding on imaging (see above)
- Asymptomatic cord compression incidental on imaging (surgery NOT recommended)
- Complications
- Residual neurologic deficits are common (e.g. pain, spasticity, neurogenic Bladder or bowel)
- C5 Nerve injury (30%)
- Recurrent laryngeal nerve injury (2.7%)
- Superficial laryngeal nerve injury (1.3%)
- Vertebral Artery injury (4.1%)
- Prognosis: Predictors of best outcome
- Younger patients with fewer comorbidities
- Non-smokers
- No gait dysfunction
- Indications
XIV. Course
- Gradual onset at age 50 with slow progression
- Surgical management needed for severe symptoms in 20-60% of patients at 3-6 years from onset