Neck Pain

Differential Diagnosis

The differential diagnosis of neck pain is broad, but includes trauma and non-musculoskeletal disease processes that can be classified as neoplastic, inflammatory, infectious, vascular, endocrinological, or neurological.

• Non-specific neck pain
• Acute disc prolapse
• Acute torticollis
• Acute trauma (for example, whiplash type injury)
• Adverse dystonic drug reactions (for example, antipsychotic drugs, metoclopramide)
• Arthritis of the cervical spine
• Cervical strain/fracture/dislocation/myelopathy
• Cervical radiculopathy
• Fibromyalgia and psychogenic conditions
• Infections (for example, meningitis, osteomyelitis)
• Malignancy
• Neurological disorders leading to dystonia (for example stroke, encephalitis)

Whiplash Injury

Definition:

• An acute whiplash injury follows sudden or excessive hyperextension, hyperflexion, or rotation of the neck and causes neck pain and other symptoms. It may result from rear-end or side-impact motor vehicle collisions, but it can also occur during diving or other activities or mishaps.

Clinical features:

The most common symptoms of whiplash are:

• Neck pain which may be referred to the shoulder or arm (88-100% of people).
• Headache (54-66% of people).

Other signs and symptoms of whiplash may include:

• A reduced range of neck movements
• Muscular spasm
• Stiffness
• Deafness
• Dysphagia or nausea
• Fatigue, dizziness, or paresthesia (less common)
• Memory loss
• Temporomandibular joint pain
• Tinnitus

Assessment:

• Take a detailed medical history.
• Do not examine neck movements until clinical features which may indicate a serious injury have been excluded.
• Palpate the neck for tenderness and assess neck movements if/when appropriate.
• Apply the Canadian C-spine rule in people aged 65 years or under to determine whether X-ray of the cervical spine is required for diagnosis of fracture or dislocation.
• Evaluate for evidence of neurological involvement (for example, decrease in sensation, or strength, or abnormal reflexes).

Management:

• Offer self-care advice:
  • Provide reassurance that recovery from whiplash-associated disorder usually occurs within the first 2 to 3 months.
  • Encourage early return to usual non-provocative, pre-accident activities and early mobilisation.
  • Discourage rest, immobilisation, and the use of soft collars.
• Offer oral analgesics (for example, ibuprofen, paracetamol or codeine) — the choice depends on the severity of pain, personal preferences, tolerability, and risk of adverse effects.
• Consider referral to physiotherapy for a multimodal treatment strategy, which may include range of motion exercises, strengthening and stretching exercises, and some form of manual therapy.

Cervical Radiculopathy

Definition:

• Cervical radiculopathy is the term used to describe the pain in one or both of the upper extremities which corresponds to the dermatome of the involved cervical nerve root. It often occurs alongside neck pain which is secondary to compression, or irritation of nerve roots in the cervical spine.

Causes:

• The most common causes of cervical radiculopathy are degenerative changes, including cervical disc herniation, and spondylosis. Other possible causes include trauma.

Clinical features:

Symptoms of cervical radiculopathy include:

• Pain in the neck, shoulder and/or arm that approximates to that of a dermatome. It is usually unilateral, but may be bilateral. The pain may be severe enough to wake the person at night.
• Sensory symptoms, such as absent or altered sensation (for example, shooting pains, numbness, and hyperaesthesia). Sensory symptoms are more common than motor symptoms.
• Motor symptoms, such as muscle weakness. Gradual onset, although it may be abrupt. The most common nerve root affected is C7, followed by C6.

Signs of cervical radiculopathy include:

• Postural asymmetry — the head may be held to one side or flexed, as this decompresses the nerve root. If the asymmetry is long-standing, muscle wasting may be present.
• Neck movements — these may be restricted, or sharp pain may radiate into the arms (especially on extension or on bending or turning to the affected side).
• Dural irritation — assess with the Spurling test. Flex the neck laterally, rotate and then press on top of the person's head. The test is positive if this pressure causes the typical radicular arm pain.
• Neurological problems — for example, upper limb weakness, paraesthesia, dermatomal sensory or motor deficit, or diminished tendon reflexes at the appropriate level. Nerve root symptoms should normally arise from a single nerve root — involvement of more than one nerve root suggests a more widespread neurological disorder.
• Atypical signs of cervical radiculopathy include: deltoid weakness, scapular winging, weakness of the intrinsic muscles of the hand, chest or deep breast pain, and headaches.

Differential diagnosis:

• Abscess: fever, neurological deficit, pain
• Anterior interosseous nerve entrapment: grip and pinch weakness, no pain
• Arteriovenous malformation: numbness, paresthesias, variable pain, weakness
• Carpal tunnel syndrome: numbness in radial 3 1/2 fingers, paresthesias, thenar weakness
• Cubital tunnel syndrome: flexor digitorum profundus weakness, numbness in ulnar half of ring and little fingers, paresthesias
• Herpes zoster: vesicular rash
• Posterior interosseous nerve entrapment: finger and wrist weakness, pain
• Radial tunnel syndrome: pain only at the radial forearm
• Reflex sympathetic dystrophy: oedema, pain, skin discolouration
• Rotator cuff tendonitis: shoulder pain with potential radiation to arm
• Thoracic outlet syndrome: pain, swelling, vascular insufficiency

Investigations:

• Cervical X-rays, and other imaging studies and investigations are not routinely required to diagnose neck pain with radiculopathy.
• Magnetic resonance imaging (MRI) is indicated in people with complex cervical radiculopathy. For example, if there is a high suspicion for myelopathy or abscess, persistent or progressive objective neurologic findings, or failure to improve after four to six weeks of conservative treatment.

Management

• If cervical radiculopathy has been present for less than 4–6 weeks and there are no objective neurological signs, provide conservative management:
  • Offer oral analgesics (for example, ibuprofen, paracetamol or codeine) — the choice depends on the severity of pain, personal preferences, tolerability, and risk of adverse effects.
  • Consider offering amitriptyline, duloxetine, pregabalin or gabapentin.
  • Consider prescribing muscle relaxants.
  • Provide reassurance and information — the long-term prognosis of people with radiculopathy is good and most cases improve without surgery.
• If cervical radiculopathy has been present for 4–6 weeks or more, or there are objective neurological signs:
  • Refer to confirm the diagnosis with magnetic resonance imaging (MRI), and to consider invasive procedures, such as interlaminar cervical epidural injections, transforaminal injections, or spinal surgery.
  • Indications for surgery include signs and symptoms of cervical radiculopathy, and cervical radiculopathy with unremitting radicular pain despite 6 to 12 weeks of conservative treatments, or progressive motor weakness, and MRI that shows nerve root compression.

Nerve Root Involvement

Nerve Root	Muscle Weakness	Reflex Changes	Sensory Changes
C5	Shoulder abduction and flexion, Elbow flexion	Biceps	Lateral arm
C6	Elbow flexion, Wrist extension	Biceps, Supinator	Lateral forearm, Thumb, Index finger
C7	Elbow extension, Wrist flexion, Finger extension	Triceps	Middle finger
C8	Finger flexion	None	Medial side lower forearm, Ring and little fingers
T1	Finger abduction and adduction	None	Medial side upper forearm, Lower arm