Can C-Reactive Protein (CRP) be elevated with neck strain?

CRP and Neck Strain

CRP is typically not elevated with simple mechanical neck strain, as uncomplicated musculoskeletal strain does not trigger a systemic inflammatory response. Elevated CRP in the setting of neck pain should prompt evaluation for serious underlying pathology rather than being attributed to muscle strain alone.

When CRP Elevation Indicates Serious Pathology

Elevated CRP with neck pain is considered a "red flag" that warrants imaging and further workup to exclude infection, inflammatory arthritis, malignancy, or other serious conditions 1. The ACR Appropriateness Criteria explicitly lists elevated inflammatory markers (including CRP) alongside fever, constitutional symptoms, and immunosuppression as indicators requiring investigation beyond simple mechanical neck pain 1.

Key Clinical Distinctions

• Simple neck strain: Does not cause systemic inflammation or CRP elevation 1
• Serious cervical pathology: Associated with elevated CRP and requires urgent evaluation 1

Conditions That DO Elevate CRP with Neck Pain

Cervical Spine Infection

• Vertebral osteomyelitis and discitis cause marked CRP elevation 1
• CRP combined with ESR is recommended for assessment when spinal infection is suspected 1
• CT demonstrates abnormalities in nearly half of patients within the first 2 weeks of infection 1

Crowned Dens Syndrome

• Crystal deposition around the odontoid process causes acute neck pain with elevated CRP 2
• Characterized by severe limitation of neck rotation with minimal limitation on flexion 2
• One case report specifically noted a patient suspected of neck strain who actually had crowned dens syndrome, where "there was no fever and no elevated CRP" initially, but imaging revealed the true diagnosis 2

Inflammatory Arthropathies

• Inflammatory conditions affecting the cervical spine elevate CRP 1
• Serologic tests including CRP can be difficult to interpret when underlying inflammatory arthropathy is present 1

Clinical Approach to Elevated CRP with Neck Pain

When CRP is ≥10 mg/L with neck pain, repeat testing and examine for sources of infection or inflammation 3. The magnitude of elevation provides diagnostic clues 3:

• Acute bacterial infections: median ~120 mg/L
• Inflammatory diseases: median ~65 mg/L
• Non-bacterial infections: median ~32 mg/L

Imaging Recommendations

• MRI cervical spine is the most sensitive modality for detecting soft tissue abnormalities, epidural collections, and spinal cord involvement 1
• CT with IV contrast is superior for detecting early bone changes, osteolysis, and bone erosions 1
• Plain radiographs alone are insufficient when infection or inflammatory pathology is suspected 1

Important Caveats

CRP is a non-specific marker of inflammation that can be elevated in many conditions 4. Normal CRP is typically <3 mg/L but can rise above 500 mg/L during acute illness 3.

Do not attribute elevated CRP to simple neck strain—this represents a critical diagnostic pitfall that may delay recognition of serious pathology 1. The combination of neck pain with elevated inflammatory markers mandates evaluation for infection, inflammatory arthritis, malignancy, or other systemic conditions rather than reassurance about benign musculoskeletal strain 1.