Neck Pain

Chapter 19 | Part 2: Cardinal Manifestations and Presentation of Diseases

KEY CLINICAL POINTS

• Neck pain is the fourth leading cause of disability in the United States with a lifetime prevalence of nearly 50%, peaking in late middle life
• Red flags requiring urgent investigation include history of cancer, fever, weight loss, progressive neurologic deficits, myelopathic signs (Hoffmann's sign, clonus, gait disturbance), and bladder/bowel incontinence
• Degenerative cervical myelopathy diagnosis is often delayed up to 2 years; early recognition and prompt surgical referral improve outcomes
• C7 is the most frequently affected nerve root in cervical radiculopathy, followed by C6
• Most acute neck pain improves spontaneously; conservative management with NSAIDs, physical therapy, and activity modification is first-line treatment

1. DEFINITION & OVERVIEW

Neck pain is a highly prevalent global problem arising most commonly from diseases of the cervical spine and soft tissues of the neck. It is typically precipitated by movement and may be accompanied by focal tenderness and limitation of motion. Pain arising from the brachial plexus, shoulder, or peripheral nerves can sometimes be confused with cervical spine disease, but history and examination usually identify a more distal origin. The underlying causes of neck pain are diverse, and patients often present with nonspecific and vague symptoms; occipital headache is a common complaint. A systematic approach to evaluation and management is essential, particularly to recognize dangerous etiologies including infection, malignancy, or spinal cord involvement from any cause. When evaluating neck pain, clinicians should identify if the pain has a neuropathic component, indicating that the pain originates from identifiable nerves producing cervical radiculopathy.

2. EPIDEMIOLOGY

Neck pain represents a significant global health burden with substantial impact on quality of life and productivity.

2.1 Prevalence and Demographics

• Lifetime prevalence: nearly 50%
• Fourth leading cause of disability in the United States
• Affects people of all ages, genders, and professions
• Women at higher risk than men
• Incidence increases with age, peaking in late middle life

2.2 Risk Factors

• Sport- and work-related injuries
• Low job satisfaction and poor work support (play a role in work-related neck pain)
• Genetic factors
• Headaches
• Sleep disorders
• Smoking
• Obesity
• Sedentary lifestyle
• Secondary gain
• History of neck pain
• Trauma
• Back pain
• Poor overall physical or mental health

3. ETIOLOGY & PATHOPHYSIOLOGY

The causes of neck pain are diverse, ranging from benign musculoskeletal conditions to life-threatening pathologies requiring urgent intervention.

3.1 Degenerative Causes

CERVICAL RADICULOPATHY: - Occurs when a cervical spinal nerve root is compressed - Herniated cervical disks cause ~25% of cervical radiculopathy - Protruding cervical disks and narrowing intervertebral foramen due to osteophytic spurs, hypertrophic facet joints, and uncovertebral joints account for ~70% of cases - C7 is the most frequently affected nerve root, followed by C6 - Mechanisms include ischemia and hypoxia of the affected nerve root DEGENERATIVE CERVICAL DISK DISEASE: - Degenerative disks contain inflammatory mediators including proinflammatory cytokines - These lead to stimulation of inflammation-responsive sensory nerve fibers innervating intervertebral disks - Results in nociceptive or "discogenic" pain - Herniated cervical disks can cause radiculopathy and myelopathy DEGENERATIVE CERVICAL MYELOPATHY: - Comprehensive term for various degenerative diseases causing symptomatic cervical spine narrowing - Includes: cervical spondylosis, ossification of the posterior longitudinal ligament, degenerative disk disease, ossification of the ligamentum flavum - These conditions compress the cervical spinal cord leading to spinal cord injury - Diagnosis often delayed up to 2 years after symptom onset - Deterioration typically slow, occurring in stepwise progressive fashion

3.2 Neoplastic Causes

• Metastases are the most common extradural spinal tumors
• Cervical spine involved in <20% of patients with spinal metastatic tumors
• Pain tends to be unrelieved by rest and worse at night
• Metastases may cause pathological fractures Primary spinal cord tumors:
• Schwannomas, meningiomas, intramedullary tumors: cause neuropathic neck pain
• Primary spinal bone tumors (hemangiomas, chordomas): cause nociceptive neck pain
• Systemic tumors (multiple myeloma, lymphoma): may cause neck pain when cervical spine involved

3.3 Infectious Causes

• Cervical vertebral osteomyelitis and diskitis: less common than thoracic/lumbar regions; causes constant neck pain
• Fever may be absent, leading to delayed diagnosis
• Risk factors: intravenous drug abuse, immunocompromised status, diabetes mellitus
• Cervical epidural abscess: causes severe neck pain and progressive neurologic deterioration due to cord compression; often requires urgent surgical intervention
• Meningitis: causes neck pain usually accompanied by fever and headache

3.4 Vascular Causes

• Vertebral and carotid artery dissections: sudden neck pain and headache
• Acute coronary syndromes: may present as referred neck pain
• Cervical arteriovenous malformations: cause acute neck pain when bleeding occurs
• Cervical epidural hematomas: sudden neck pain with neurologic deficits; may be misdiagnosed as stroke - Distinguishing sign: neck pain aggravated by palpation of spinous process

3.5 Congenital Causes

Chiari Type 1 Malformations: - Cause headache and neck pain aggravated by cough - Pathophysiology unclear but may involve: - Dissociation between intracranial and intraspinal pressures - Traction on pain-sensitive nerves of the dura mater

3.6 Autoimmune/Inflammatory Causes

RHEUMATOID ARTHRITIS: - Commonly affects cervical spine - ~50% of patients have atlantoaxial subluxation - May lead to neurologic deterioration POLYMYALGIA RHEUMATICA: - Pain and stiffness in neck, shoulder, and pelvic girdle - Accompanied by systemic symptoms ANKYLOSING SPONDYLITIS: - Causes neck pain (chronic back pain more common) - Pain typically worsens with rest or inactivity CROWNED DENS SYNDROME: - Also known as periodontoid calcium pyrophosphate dihydrate crystal deposition disease - Causes severe neck pain and neck stiffness

3.7 Endocrine/Metabolic Causes

PAGET'S DISEASE: - Bone disorder characterized by imbalance in bone modeling and remodeling - Less common in cervical spine vs. thoracolumbar regions - Pain tends to be worse at rest OSTEOPOROSIS: - Sometimes induced by hyperparathyroidism and glucocorticoid therapy - Can produce pathological bone fractures OSTEOMALACIA: - Due to abnormal vitamin D metabolism - Usually affects lumbar or lower thoracic vertebrae - Neck pain occurs when cervical spine affected

3.8 Traumatic Causes

TRAUMATIC FRACTURE AND DISLOCATION: - Life-threatening when accompanied by cervical spinal cord injury - Nociceptive and neuropathic pains can be combined - Immobilization essential to reduce pain and prevent further cord injury WHIPLASH INJURY: - Usually caused by motor vehicle collisions - Injury to facet joints believed to underlie pain syndrome - ~50% of patients have persistent neck pain at 1 year

3.9 Other Causes

CERVICAL MYOFASCIAL PAIN: - Very common clinical condition - Can involve diffuse areas around neck and shoulder - Restriction of cervical spine motions can cause nonspecific neck pain - Myofascial trigger points (palpable nodules inside taut muscle bands) are hallmark of myofascial pain

4. CLINICAL FEATURES

Clinical presentation varies depending on the underlying etiology and structures involved.

Table 19-1: Cervical Radiculopathy - Neurologic Features

Nerve Root	Reflex	Sensory	Motor	Pain Distribution
C5	Biceps	Lateral deltoid	Rhomboids (elbow extends backward with hand on hip); Infraspinatus (arm rotates externally with elbow flexed at side); Deltoid* (arm raised laterally 30°-45° from side)	Lateral arm, medial scapula
C6	Biceps	Palmar thumb/index finger; Dorsal hand/lateral forearm	Biceps* (arm flexed at elbow in supination); Pronator teres (forearm pronated)	Lateral forearm, thumb/index fingers

Nerve Root	Reflex	Sensory	Motor	Pain Distribution
C7	Triceps	Middle finger; Dorsal forearm	Triceps (forearm extension, flexed at elbow); Wrist/finger extensors	Posterior arm, dorsal forearm, dorsal hand
C8	Finger flexors	Palmar surface of little finger; Medial hand and forearm	Abductor pollicis brevis (thumb abduction); First dorsal interosseous (index finger abduction); Abductor digiti minimi (little finger abduction)	Fourth and fifth fingers, medial hand and forearm
T1	Finger flexors	Axilla, medial arm, anteromedial forearm	Abductor pollicis brevis (thumb abduction); First dorsal interosseous (index finger abduction); Abductor digiti minimi (little finger abduction)	Medial arm, axilla

4.1 History Taking

Essential elements of history: - Occupation, general health, past medical history - Characteristics of pain: dull, sharp, electric, stabbing, spasms - Aggravating and alleviating factors - Radiating pain into occiput, arms, or hands (suggests radiculopathy) Specific symptoms to inquire about: - Numbness or tingling in extremities - Clumsiness in hands - Change in handwriting - Difficulty with buttons - Unsteady gait - Saddle paresthesia - Bladder or bowel incontinence

4.2 Cervical Radiculopathy Presentation

• Besides neck pain, commonly accompanied by: - Pain in shoulder, interscapular, or upper limb - Sensory disturbance - Motor weakness
• Distribution depends on affected nerve root
• Neck pain can be the only symptom, especially with C4 or higher nerve root involvement
• Radicular pain typically follows dermatomal distributions

4.3 Cervical Myelopathy Presentation

EARLY SIGNS (often mild and easily overlooked): - Paresthesia - Minor loss of hand dexterity - Feelings of "clumsiness" LATE/SEVERE SIGNS: - Gait disturbance - Quadriparesis - Bowel or bladder incontinence

4.4 Physical Examination

OBSERVATION: - Examine head, neck, and shoulder for deformity, mass, skin changes, signs of trauma - Determine location and quantity of pain - Assess interference with daily function and activities RANGE OF MOTION: - 50% of cervical motion (flexion, extension, rotation) originates from atlantoaxial joint (C1-C2) - 50% from subaxial spine (C3-C7) - Any motion restriction requires further investigation

4.5 Special Tests

SPURLING'S MANEUVER: - Test for radiculopathy from cervical spine - Performed by passively rotating and flexing patient's neck laterally and applying axial compression to top of head - Positive if triggers or worsens upper extremity radiculopathy symptoms LHERMITTE'S SIGN: - Elicited by gently flexing patient's neck - Positive if reproduces electric pain down spine or extremities - Signifies underlying cervical spinal pathology HOFFMANN'S TEST: - Perform whenever cervical spinal cord pathology suspected - Sign of hyperreflexia - Positive when patient involuntarily flexes and adducts thumb and index finger while examiner snaps distal phalanx of middle finger ANKLE CLONUS: - More than three beats when ankle briskly dorsiflexed and held under pressure - Upper motor neuron sign signifying spinal cord pathology TANDEM (HEEL-TO-TOE) GAIT: - Dependent on proprioception, coordination, and strength - Imbalance suggests possible spinal cord compression

5. DIFFERENTIAL DIAGNOSIS

The differential diagnosis of neck pain is broad and includes both benign and life-threatening conditions.

Table 19-2: Clinical Features Suggesting Need for Further Investigation in Neck Pain

History Red Flags	Physical Exam Red Flags
History of congenital disorders	Fever
History of cancer	Neck stiffness
History of substance abuse	Severe neck pain and tenderness

History Red Flags	Physical Exam Red Flags
History of inflammatory arthritis	Torticollis
Recent trauma to head and neck	Motor weakness in upper or lower extremities
Signs or symptoms of infection	Sensory changes in upper or lower extremities
Family history of spinal conditions	Upper motor neuron signs: Hoffmann, clonus, Babinski
Unexplained weight loss	Hyperreflexia
Progressive neurologic deficits	Unsteady gait
Saddle anesthesia	Difficulty with tandem or heel-to-toe walk
Bladder or bowel incontinence

5.1 Categories of Neck Pain Etiology

DEGENERATIVE: - Cervical radiculopathy - Degenerative cervical disk disease - Degenerative cervical myelopathy - Cervical spondylosis NEOPLASTIC: - Metastatic tumors - Primary spinal cord tumors (schwannomas, meningiomas) - Primary bone tumors (hemangiomas, chordomas) - Systemic tumors (multiple myeloma, lymphoma) INFECTIOUS: - Vertebral osteomyelitis/diskitis - Epidural abscess - Meningitis VASCULAR: - Vertebral/carotid artery dissection - Acute coronary syndrome (referred pain) - Arteriovenous malformation - Epidural hematoma CONGENITAL: - Chiari type 1 malformation AUTOIMMUNE/INFLAMMATORY: - Rheumatoid arthritis - Polymyalgia rheumatica - Ankylosing spondylitis - Crowned dens syndrome ENDOCRINE/METABOLIC: - Paget's disease - Osteoporosis - Osteomalacia TRAUMATIC: - Fracture/dislocation - Whiplash injury OTHER: - Cervical myofascial pain - Brachial plexus pathology - Shoulder pathology - Peripheral nerve disorders

6. INVESTIGATIONS & DIAGNOSIS

Diagnostic workup should be guided by clinical history and physical examination findings.

6.1 Imaging Studies

CERVICAL SPINE X-RAYS: - Simple, readily accessible diagnostic tool - Views: anterior-posterior, lateral, flexion-extension - Useful for screening: fractures, instability, osteoarthritis - Can prompt further investigations COMPUTED TOMOGRAPHY (CT): - Indicated for concerns of spinal column fractures - Useful for assessing previous surgical instrumentation/hardware complications - Limitation: poor visualization of soft tissues; not helpful for evaluating spinal cord or intervertebral disk pathologies MAGNETIC RESONANCE IMAGING (MRI): - Gold standard for assessing soft tissue structures - Indications: - Radiculopathy symptoms - Signs of myelopathy or other neurologic deficits - Ruling out malignancy or infectious causes - Caution: high rate of abnormal findings (especially degenerative changes) in asymptomatic individuals - Should be performed only with strong indications based on history, exam, and screening radiographs CT MYELOGRAPHY: - For patients in whom MRI is contraindicated - Contrast injected into spinal canal prior to CT - Assesses spinal cord and surrounding structures

6.2 Electrodiagnostic Studies

ELECTROMYOGRAPHY (EMG) AND NERVE CONDUCTION STUDIES (NCS): - Typically unnecessary when diagnosis is clear - Helpful when symptoms do not correlate with MRI findings - Measures electrical response to nerve stimulation in muscles and conduction velocity - Can distinguish: - Radiculopathy arising from spine - Peripheral neuropathy - Brachial plexopathy - Referral to neurologist recommended if high clinical suspicion with negative electrodiagnostic findings

6.3 Laboratory Tests

• Limited value in assessment of most patients with neck pain
• Obtain appropriate blood panels when clinical suspicion of: - Underlying infection - Malignancy - Inflammatory arthritis - Neuromuscular disorder

6.4 Diagnostic Algorithm

1. Complete clinical history and physical examination
2. Identify red flags (Table 19-2)
3. If red flags present → urgent further investigation
4. If neurologic deficits present → MRI cervical spine
5. If fracture suspected → CT scan
6. If symptoms do not correlate with MRI → EMG/NCS
7. If MRI contraindicated → CT myelography
8. Consider laboratory workup if infection, malignancy, or inflammatory condition suspected

7. MANAGEMENT & TREATMENT

Treatment should be tailored to the underlying condition. Recognition of red flags indicating myelopathy, malignancy, infection, or severe spinal injury requires urgent assessment.

7.1 Neck Pain Without Radiculopathy or Neurologic Findings

ACUTE NECK PAIN: - Spontaneous improvement is the norm - Goals: promote rapid return to normal function and provide pain relief while healing proceeds - Patient education regarding favorable natural history is essential to avoid unrealistic fear and inappropriate requests for imaging Pharmacologic: - NSAIDs - Acetaminophen - NSAIDs + acetaminophen combination - Cyclobenzaprine 5-10 mg at night for patients with sleep disturbance (relieves muscle spasm and promotes drowsiness) Non-pharmacologic: - Cold packs or heat - Supervised exercise with or without mobilization (appears effective) - Exercises: shoulder rolls, neck stretches - McKenzie method of physical therapy - Soft neck collar (modest relief with little risk or cost) - Massage (temporary pain relief) CHRONIC NECK PAIN: - Supervised exercise programs: provide symptom relief and improve function - Acupuncture: short-term benefit compared to sham procedure; reasonable option - Spinal manipulation alone: NOT shown to be effective and carries risk of injury REFRACTORY PAIN: - Referral to pain specialist recommended - Fluoroscopically guided radiofrequency ablation effective for facet joint-origin pain - Careful patient selection essential for optimal outcomes - Specialist referral highly recommended before considering such procedures

7.2 Neck Pain With Radiculopathy or Neurologic Findings

NATURAL HISTORY: - Favorable for acute neck pain with radiculopathy due to disk disease - Many patients improve without specific therapy INITIAL THERAPY: - NSAIDs, acetaminophen, or both (no randomized trials but reasonable) - Muscle relaxants - Avoidance of activities that trigger symptoms - Gentle supervised exercise - Avoidance of inactivity - Soft cervical collars (modestly helpful by limiting neck movements that exacerbate pain; hard collars poorly tolerated) - Opioid analgesics: emergency department and short outpatient courses only STEROID THERAPY: - Short course of high-dose oral glucocorticoids with rapid taper OR - Epidural steroids administered under imaging guidance - Can be effective for acute/subacute disk-related cervical radicular pain - NOT subjected to rigorous trials - Higher risk of injection-related complications in neck vs. low back: - Vertebral artery dissection - Dural puncture - Spinal cord injury - Embolism in vertebral arteries CERVICAL SPONDYLOSIS WITH FORAMINAL NARROWING: - Periodic follow-up to assess for progression - Consider surgical decompression

7.3 Surgical Treatment

ROLE OF SURGERY: - Very limited role in patients with acute/chronic neck pain without: - Neurologic findings - Spine instability - Fractures INDICATIONS FOR CERVICAL DISK SURGERY: - Progressive motor deficit due to nerve root compression - Functionally limiting pain that fails to respond to conservative management - Spinal cord compression OUTCOMES: - Surgery can produce rapid pain relief - Unclear if long-term functional outcomes improved over nonsurgical therapy - In other circumstances, clinical improvement over time is common regardless of therapeutic intervention SURGICAL PROCEDURES: - Anterior cervical diskectomy/corpectomy and fusion - Posterior cervical laminectomy - Laminoplasty - Laminectomy with fusion ADJACENT SEGMENT DISEASE: - Risk of subsequent radiculopathy or myelopathy at segments adjacent to fusion: ~3% per year, 26% per decade - May reflect natural history of degenerative cervical disk disease rather than surgery complication

8. PROGNOSIS & COMPLICATIONS

Prognosis varies based on underlying etiology and presence of neurologic involvement.

8.1 Prognosis

ACUTE NECK PAIN WITHOUT RADICULOPATHY: - Spontaneous improvement is the norm - Favorable natural history ACUTE NECK PAIN WITH RADICULOPATHY (disk disease): - Natural history is favorable - Many patients improve without specific therapy DEGENERATIVE CERVICAL MYELOPATHY: - Deterioration typically slow and stepwise progressive - Prompt diagnosis and timely surgical intervention at initial phase results in better clinical outcomes WHIPLASH INJURY: - ~50% of patients have persistent neck pain at 1 year

8.2 Complications

DISEASE-RELATED: - Progressive neurologic deterioration (myelopathy, radiculopathy) - Spinal cord compression - Pathological fractures (metastatic disease, osteoporosis) TREATMENT-RELATED (Epidural Steroid Injections): - Vertebral artery dissection - Dural puncture - Spinal cord injury - Embolism in vertebral arteries SURGICAL COMPLICATIONS: - Adjacent segment disease: ~3% per year, 26% per decade after fusion

9. SPECIAL CONSIDERATIONS

Certain populations and conditions require heightened awareness and modified approaches.

9.1 High-Risk Populations

INTRAVENOUS DRUG USERS: - Higher risk for vertebral osteomyelitis, diskitis, epidural abscess - Maintain high index of suspicion for infectious causes IMMUNOCOMPROMISED PATIENTS: - Increased risk for spinal infections - May have atypical presentations with absent fever DIABETES MELLITUS: - Predisposed to spinal infections - Consider infectious etiology in unexplained neck pain CANCER PATIENTS: - Pain unrelieved by rest and worse at night suggests metastatic disease - Urgent imaging indicated

9.2 Urgent/Emergent Conditions

CERVICAL EPIDURAL ABSCESS: - Severe neck pain with progressive neurologic deterioration - Often requires urgent surgical intervention CERVICAL SPINE FRACTURE/DISLOCATION: - Life-threatening when accompanied by spinal cord injury - Immediate immobilization essential CERVICAL EPIDURAL HEMATOMA: - Sudden neck pain with neurologic deficits - May be misdiagnosed as stroke - Distinguishing feature: neck pain aggravated by spinous process palpation ARTERIAL DISSECTION: - Sudden neck pain with headache - Requires immediate vascular imaging

10. KEY POINTS & CLINICAL PEARLS

Essential takeaways for clinical practice.

10.1 Diagnostic Pearls

• 50% of cervical motion (flexion, extension, rotation) originates from C1-C2 joint; 50% from C3-C7
• C7 is the most commonly affected nerve root in cervical radiculopathy, followed by C6
• Degenerative cervical myelopathy diagnosis is often delayed up to 2 years - early recognition improves outcomes
• High rate of abnormal MRI findings in asymptomatic individuals - interpret imaging in clinical context
• EMG/NCS can distinguish radiculopathy from peripheral neuropathy and brachial plexopathy when symptoms don't correlate with MRI

10.2 Management Pearls

• Most acute neck pain improves spontaneously - patient education about favorable natural history is essential
• Spinal manipulation alone is NOT effective and carries injury risk
• Epidural steroid injections have higher complication risk in cervical vs. lumbar spine
• Surgery indications: progressive motor deficit, refractory functionally limiting pain, spinal cord compression
• Adjacent segment disease occurs at ~3% per year after cervical fusion

10.3 Red Flag Summary

URGENT INVESTIGATION REQUIRED FOR: - History of cancer + neck pain (especially if worse at night, unrelieved by rest) - Fever with neck pain - Progressive neurologic deficits - Signs of myelopathy: Hoffmann's sign positive, clonus >3 beats, gait disturbance, bladder/bowel dysfunction - Recent trauma with suspected fracture/instability - Signs/symptoms of infection in high-risk patients