What is the pathophysiology and management of cervical muscle strain?

Pathophysiology of Cervical Muscle Strain

Cervical muscle strain results from injury to neck structures that causes somatosensory dysfunction and aberrant signaling along cervical afferent pathways, leading to neck pain, stiffness, muscle tenderness, and often occipital/suboccipital headaches. 1

Primary Pathophysiological Mechanisms

Direct Tissue Injury and Neural Dysfunction

• Injury to cervical structures disrupts normal cervical afferent pathways that travel to the brain, which are typically involved in coordinating cervical and vestibular reflexes and supporting normal vision and vestibular functioning 1
• The aberrant signaling and transmission along these damaged pathways produces the characteristic symptoms of neck pain, stiffness, weakness, and persistent headache 1
• Patients develop clinical signs including pain and tenderness in the cervical spine (midline, paraspinal, and suboccipital muscles), weakness with paracervical strength testing, limitation of cervical motion, and pain with cervical movement 1

Pain Referral Patterns

• Cervical strain causes persistent headache that is characteristically occipital or suboccipital in location due to the somatosensory dysfunction and aberrant cervical afferent signaling 2
• Patients may experience pain or paresthesia in the occipital region during palpation or head movement, reflecting the referred pain pattern from injured cervical structures 2

Clinical Presentation and Physical Findings

Characteristic Signs

• Palpable muscle tightness in the cervical paraspinal muscles is a hallmark finding 2
• Visible muscle spasm, swelling, or bruising may be present on inspection 2
• Tenderness, muscle tightness, or nodules are detectable on palpation 2
• Limitation of neck motion and pain with movement are typical 1, 2

Associated Symptoms

• Upper extremity weakness or paresthesia (radicular symptoms) may occur 1
• Occipital/suboccipital headaches are common due to the cervical afferent pathway dysfunction 1, 2

Important Clinical Distinctions

Because cervical strain and concussion share common injury mechanisms, differentiating isolated versus concomitant etiologies (such as whiplash-associated disorder) is critical for determining appropriate management and treatment. 1 This distinction requires careful assessment of the mechanism of injury, onset of symptoms, and associated neurological findings.

Management Implications Based on Pathophysiology

Initial Treatment Approach

• Rest and activity modification combined with NSAIDs are effective for initial management of muscle strain 2
• Cyclobenzaprine (a centrally acting muscle relaxant) is FDA-approved as an adjunct to rest and physical therapy for relief of muscle spasm associated with acute, painful musculoskeletal conditions, but should only be used for short periods (up to 2-3 weeks) 3
• However, research shows little benefit to routinely adding cyclobenzaprine to NSAIDs for acute cervical strain, as pain scores improved similarly over time regardless of whether patients received ibuprofen alone, cyclobenzaprine alone, or both 4

Progressive Rehabilitation

• Progressive rehabilitation with gradual introduction of stretching and strengthening exercises improves flexibility and strength and prevents recurrence 2
• This approach addresses the underlying somatosensory dysfunction by restoring normal cervical afferent pathway function 1

Red Flags Requiring Further Investigation

• Neck pain with fever or elevated inflammatory markers 2
• Severe pain unresponsive to conservative treatment 2
• Neurological deficits suggesting nerve root or spinal cord involvement 2
• History of cancer, immunosuppression, or recent infection 2
• Neck stiffness with thunderclap headache (consider subarachnoid hemorrhage) 2