Which cervical nerve roots are affected by pain to the upper extremities, paresthesias to hands, and numbness to hands?

Cervical Nerve Roots Affected by Upper Extremity Pain, Hand Paresthesias, and Hand Numbness

The symptoms of upper extremity pain with hand paresthesias and numbness most commonly involve the C6, C7, and C8 nerve roots, though symptom overlap is extensive and precise localization based on symptoms alone is unreliable.

Primary Nerve Root Involvement

C6 and C7 Radiculopathy Predominance

• C6 and C7 nerve roots are the most frequently affected in cervical radiculopathy presenting with upper extremity pain and hand symptoms 1.
• Approximately 80% of patients with C6 or C7 radiculopathy experience impaired sensation in the distal forearm and hand, with nearly complete overlap in symptom distribution between these two roots 2.
• The only distinguishing feature is that impaired sensation in the dorsal aspect of the distal radial forearm is twice as common in C6 radiculopathy compared to C7 (p=0.02) 2.

C8 Nerve Root Consideration

• C8 radiculopathy should be considered when hand numbness and paresthesias are present, particularly affecting the ulnar aspect of the hand 3.
• C8 involvement can cause both superficial and deep pain in the interscapular and scapular regions, along with hand symptoms 4.

Critical Diagnostic Limitations

Symptom Overlap Makes Precise Localization Difficult

• Arm pain and sensory symptoms are diffuse and not distinctly different between C6 and C7 radiculopathy, requiring caution when predicting root involvement based on symptoms alone 5.
• The locations of sensory impairments associated with C6 and C7 nerve root compression overlap to such an extent that clinical examination findings have limited predictive value 2.
• Many patients have sensory findings in multiple areas simultaneously, further complicating anatomic localization 2.

Bilateral Symptoms Suggest Central Pathology

• Bilateral hand numbness with upper extremity pain should raise concern for cervical spinal cord pathology rather than isolated nerve root compression 6.
• Central cord syndrome classically presents with greater upper extremity weakness than lower extremity involvement, with bilateral hand numbness and burning dysesthesias in the forearms 6.
• MRI showing spinal cord signal changes from C3-C7 with canal narrowing confirms central cervical spine pathology requiring urgent neurosurgical evaluation 6.

Examination Findings to Assess

Motor and Reflex Testing

• Diminished deep tendon reflexes, particularly of the triceps (C7), are the most common neurologic finding in cervical radiculopathy 1.
• Approximately 41% of patients report some weakness, though specific descriptions have limited value for differentiating between C6 and C7 radiculopathy 5.
• Weakness with upper extremity muscle myotome testing can indicate cervical strain or radiculopathy 7.

Provocative Testing

• The Spurling test, shoulder abduction test, and upper limb tension test can confirm cervical radiculopathy diagnosis 1.
• Painful neck movements and muscle spasm are the most common examination findings 1.

Red Flags Requiring Immediate Imaging

Indicators of Serious Pathology

• Progressive motor weakness, bilateral symptoms affecting both upper AND lower extremities, new bladder or bowel dysfunction, loss of perineal sensation, and gait disturbance require immediate MRI and possible emergency intervention 8.
• Constitutional symptoms (fever, weight loss), elevated inflammatory markers (WBC, ESR, CRP), or immunosuppression suggest infection or malignancy requiring urgent evaluation 7.

Imaging Recommendations

MRI as First-Line for Radicular Symptoms

• MRI of the cervical spine without contrast is the appropriate imaging modality for patients with radicular symptoms, as it correctly predicts 88% of cervical radiculopathy lesions 8.
• Imaging is not required for acute symptoms without red flags unless symptoms persist beyond 4-6 weeks of conservative treatment 1.
• Contrast is unnecessary unless there is concern for infection, malignancy, or prior surgery 8.

Important Clinical Pitfalls

Double Crush Syndrome

• Consider double crush syndrome when cervical nerve root compression coexists with peripheral nerve compression (such as ulnar neuropathy at the elbow), as this increases susceptibility to symptoms at multiple locations along the nerve course 3.
• Ulnar nerve mobilizations may provide immediate symptom relief when distal compression contributes to the clinical picture 3.

Cervical Strain vs. Radiculopathy

• Cervical strain can present with neck pain, upper extremity weakness, and paresthesias/weakness (radicular symptoms) in the upper extremities, making differentiation from isolated radiculopathy important for management 7.
• Both conditions share common injury mechanisms, requiring careful assessment to determine if symptoms are isolated or concomitant 7.