Residency · Residency · Physical Medicine Rehabilitation

Cervical Radiculopathy and Myelopathy

Anatomy Review

Cervical Spine Structure

7 cervical vertebrae (C1-C7) with 8 cervical nerve roots (C1-C8). C1-C2 (atlantoaxial joint): primarily rotation (~50% of cervical rotation). C3-C7: typical cervical vertebrae with uncovertebral joints (joints of Luschka), facet joints, and intervertebral discs. The cervical spinal canal is narrowest at C4-C6; canal diameter <13 mm increases myelopathy risk. Cervical nerve roots exit ABOVE their numbered pedicle (C6 root exits at C5-C6 foramen), unlike lumbar roots.

Key Neural Structures

Spinal cord occupies approximately 50% of the cervical canal. Lateral corticospinal tracts (motor): located laterally. Dorsal columns (proprioception, vibration): located posteriorly. Spinothalamic tracts (pain, temperature): located anterolaterally.

Cervical nerve roots travel through the neural foramen bordered by the uncovertebral joint anteriorly and facet joint posteriorly.

Cervical Radiculopathy

Etiology

Disc herniation: most common in younger patients (<50); typically posterolateral. Foraminal stenosis: most common in older patients; spondylotic osteophytes from uncovertebral and facet joints. Combined: disc-osteophyte complex. Less common: tumor, infection, demyelination.

Common Root Levels and Clinical Patterns

Clinical Evaluation

History

Neck pain radiating into the arm in a dermatomal pattern. Paresthesias and numbness in corresponding dermatome. Weakness in myotomal distribution. Symptoms may worsen with neck extension and ipsilateral rotation. Pain may be described as burning, sharp, or electric shock-like.

Physical Examination

Spurling test: axial compression with extension and ipsilateral rotation reproduces radicular symptoms (sensitivity ~50%, specificity ~90%). Shoulder abduction relief sign: relief of radicular pain with ipsilateral shoulder abduction (hand on head) -- suggests foraminal compression. Distraction test: relief of symptoms with manual axial traction. Upper limb tension test (ULTT/Elvey test): neural tension testing.

Motor examination: test specific myotomes (deltoid C5, wrist extensors C6, triceps C7, grip C8, finger abduction T1). Sensory examination: light touch and pinprick in dermatomal distribution. Reflexes: biceps (C5-C6), brachioradialis (C5-C6), triceps (C7). Inverted brachioradialis reflex: finger flexion with brachioradialis tap -- suggests cord compression at C5-C6.

Imaging

MRI without contrast: study of choice; shows disc herniation, foraminal stenosis, cord compression. CT myelography: alternative if MRI contraindicated; superior bony detail. Radiographs: assess alignment, foraminal narrowing, instability on flexion-extension views. Electrodiagnostics: EMG/NCS to confirm radiculopathy, rule out peripheral neuropathy, plexopathy, or entrapment neuropathy (see Topic 13).

Conservative Management (Effective in 75-90% of Cases)

Activity modification: avoid prolonged neck extension and overhead activities. Cervical collar: short-term use only (1-2 weeks maximum) for acute pain relief. Physical therapy: Cervical traction (mechanical or manual): 10-15 lbs, 15-20 minutes. Cervical ROM exercises. Deep neck flexor strengthening. Scapular stabilization. Neural mobilization/gliding techniques.

Postural education (forward head posture correction). Pharmacologic: NSAIDs, short course oral corticosteroids (Medrol dose pack), neuropathic pain agents (gabapentin, pregabalin). Cervical epidural steroid injection: transforaminal or interlaminar approach; evidence for short-term pain relief to facilitate therapy.

Surgical Referral Indications

Progressive motor deficit. Failure of 6-12 weeks of conservative management with persistent disabling radicular pain. Surgical options: anterior cervical discectomy and fusion (ACDF), posterior foraminotomy, cervical disc arthroplasty.

Cervical Myelopathy

Definition

Spinal cord compression causing intrinsic cord dysfunction. Most common cause of spinal cord dysfunction in adults over 55. Insidious, progressive course -- early recognition is critical.

Etiology

Cervical spondylosis: most common; disc-osteophyte complexes, ligamentum flavum hypertrophy. Ossification of the posterior longitudinal ligament (OPLL): more common in East Asian populations. Congenital stenosis: developmental canal narrowing. Central disc herniation: acute presentation possible. Rheumatoid arthritis: atlantoaxial subluxation.

Clinical Features (Distinguish from Radiculopathy)

Upper Motor Neuron Signs

Hyperreflexia (below the level of compression). Spasticity with velocity-dependent increased tone. Pathological reflexes: Babinski sign, Hoffman sign, clonus. Hoffman sign: flicking the middle finger DIP produces thumb/index finger flexion (most sensitive early sign).

Inverted brachioradialis reflex. Lhermitte sign: electric shock sensation down the spine/limbs with neck flexion (not specific to myelopathy).

Motor Findings

Hand clumsiness: difficulty with fine motor tasks (buttoning, writing, picking up coins). Myelopathy hand sign (finger escape sign): inability to rapidly grip and release; small finger abduction and extension. Gait disturbance: wide-based, spastic gait; difficulty with tandem walking. Lower extremity weakness and stiffness.

Sensory Findings

Numbness in hands (often in a non-dermatomal pattern). Loss of proprioception and vibration (dorsal column dysfunction). Variable pain and temperature loss (spinothalamic tract).

Bowel/Bladder

Urinary urgency, frequency, or incontinence (late finding). Bowel dysfunction.

Myelopathy Severity Grading

Modified Japanese Orthopaedic Association (mJOA) score: most widely used. Mild: 15-17. Moderate: 12-14. Severe: <12. Nurick grading: 0 (root signs only) to 5 (wheelchair/bedbound).

Imaging

MRI: essential; shows cord compression, T2 signal change within the cord (myelomalacia -- poor prognostic sign), T1 hypointensity (worse prognosis). CT: bony detail, OPLL characterization. Dynamic radiographs: assess instability. Spinal cord compression ratio: AP/transverse diameter of cord; <0.4 associated with worse outcomes.

Management

Surgical Referral (Primary Treatment for Myelopathy)

Moderate-to-severe myelopathy (mJOA <15): surgical decompression is the standard of care. Early surgery prevents progression; delayed surgery is associated with worse outcomes. Natural history is progressive deterioration in the majority (stepwise or gradual decline). Anterior approaches: ACDF, anterior cervical corpectomy and fusion (ACCF) -- for 1-2 level disease.

Posterior approaches: laminoplasty, laminectomy with fusion -- for multilevel disease. Combined approaches: for severe or complex cases.

Mild Myelopathy (Controversial)

Some advocate early surgery to prevent progression. Others support structured conservative monitoring with serial examinations. Close follow-up with repeat MRI and clinical assessment every 3-6 months. Any sign of progression should prompt surgical referral.

Rehabilitation in Myelopathy

Pre-operative optimization of function. Post-surgical rehabilitation: gait training, balance, hand function, ADL retraining. Spasticity management if needed. Cervical stabilization program (post-operative, once cleared by surgeon). Fall prevention.

Differentiating Radiculopathy from Myelopathy

<image>Axial cross-section of the cervical spinal cord at C5-C6 level showing the major ascending and descending tracts: lateral corticospinal tract (labeled, lateral), dorsal columns (fasciculus gracilis and cuneatus, posterior), spinothalamic tract (anterolateral), and anterior corticospinal tract (anterior). Show a posterolateral disc herniation compressing the exiting nerve root in the neural foramen and the uncovertebral and facet joints. Label the vertebral artery in the transverse foramen.</image>

<image>Side-by-side clinical comparison illustration: on the left, a patient with cervical radiculopathy showing dermatomal pain radiation down the arm with a positive Spurling test; on the right, a patient with cervical myelopathy demonstrating a wide-based spastic gait, positive Hoffman sign (close-up of hand showing flicking test), and difficulty with fine motor tasks such as buttoning a shirt. Include a small inset showing the Babinski sign on the foot.</image>

<image>Sagittal MRI illustration of the cervical spine showing multilevel spondylotic changes including disc-osteophyte complexes at C4-C5 and C5-C6, ligamentum flavum hypertrophy, and resulting spinal cord compression. Show T2 hyperintensity within the compressed cord segment indicating myelomalacia. Label the anterior and posterior structures, spinal cord, and CSF space.</image>

Clinical Pearls

Always test for Hoffman sign in any patient presenting with neck pain or upper extremity symptoms -- it is the most sensitive early sign of cervical myelopathy. Cervical myelopathy may present insidiously as gait difficulty or hand clumsiness without significant neck pain. The Spurling test is highly specific for radiculopathy -- a positive test is very helpful, but a negative test does not rule it out. C5 palsy can occur as a post-operative complication after cervical decompression surgery (incidence 2-5%).

In radiculopathy, the sensory examination is less reliable than motor and reflex findings for localizing the level. Combined radiculomyelopathy is common: look for both LMN signs at the level of compression and UMN signs below it. Never apply cervical traction in patients with suspected myelopathy or instability. Rheumatoid arthritis patients require flexion-extension cervical radiographs before intubation to assess for atlantoaxial instability.

References

• Iyer S, Kim HJ. Cervical radiculopathy. Curr Rev Musculoskelet Med. 2016;9(3):272-280.
• Fehlings MG, et al. A clinical practice guideline for the management of degenerative cervical myelopathy. Global Spine J. 2017;7(3 Suppl):21S-164S.
• Rhee JM, et al. Prevalence of physical signs in cervical myelopathy: a prospective, controlled study. Spine. 2009;34(9):890-895.
• Tetreault L, et al. A systematic review of the natural history of degenerative cervical myelopathy. J Neurosurg Spine. 2015;23(4):476-485.
• Thoomes EJ, et al. Value of physical tests in diagnosing cervical radiculopathy: a systematic review. Spine J. 2018;18(1):179-189.

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