What neurological symptoms can be expected in a patient with severe foraminal narrowing at the C3, C4, and C5 levels?

Neurological Symptoms in Severe C3, C4, C5 Foraminal Narrowing

Severe foraminal narrowing at C3, C4, and C5 levels produces radicular symptoms affecting the shoulder, upper arm, and specific muscle groups innervated by these nerve roots, including shoulder abduction weakness (C5), elbow flexion weakness (C5-C6), and sensory changes in the lateral arm and forearm.

Expected Radicular Symptoms by Level

C3 Nerve Root Involvement

• Sensory changes: Numbness or paresthesias in the upper neck and posterior auricular region 1
• Motor deficits: Rarely isolated motor weakness, as C3 primarily provides sensory innervation 2

C4 Nerve Root Involvement

• Motor deficits: Weakness of shoulder shrug (trapezius contribution) and diaphragmatic breathing impairment in severe cases 2
• Sensory changes: Numbness over the lower neck and upper shoulder region 2
• Pain patterns: Radiating pain from neck to shoulder girdle 1, 3

C5 Nerve Root Involvement (Most Common Symptomatic Level)

• Motor deficits: Deltoid weakness causing difficulty with shoulder abduction, biceps weakness affecting elbow flexion 4, 5, 6
• Sensory changes: Numbness or paresthesias over the lateral shoulder and upper arm 1, 3
• Pain patterns: Severe radiating pain from neck down the lateral arm 1, 3
• Reflex changes: Diminished or absent biceps reflex 1

Critical Distinction: Radiculopathy vs. Myelopathy

Foraminal narrowing produces radiculopathy (nerve root compression), NOT myelopathy (spinal cord compression). This distinction is essential:

Radiculopathy Presentation (Expected with Foraminal Narrowing)

• Unilateral symptoms in the distribution of the affected nerve root 1, 3
• Dermatomal sensory loss or paresthesias 1, 3
• Myotomal weakness in specific muscle groups 1, 3
• Diminished reflexes at the affected level 1
• Sharp, shooting pain radiating down the arm 1, 3

Myelopathy Presentation (NOT Expected with Isolated Foraminal Narrowing)

• Bilateral hand weakness and clumsiness affecting fine motor control 7, 8
• Gait disturbance or lower extremity weakness 7, 2
• Hyperreflexia and pathological reflexes 7
• Sensory level changes below the compression 7, 2
• Bowel or bladder dysfunction in severe cases 2

If bilateral symptoms, lower extremity involvement, or hand clumsiness are present, suspect central canal stenosis with cord compression rather than isolated foraminal narrowing 7, 8.

Specific Clinical Patterns

Multiple Level Involvement (C3, C4, C5)

• Overlapping dermatomal sensory changes creating a broader area of numbness from upper neck through lateral shoulder and arm 1
• Combined motor weakness affecting multiple muscle groups: trapezius, deltoid, and biceps 4, 5
• More severe and persistent pain due to multi-level nerve root irritation 1, 3

Severity Indicators

• Severe foraminal narrowing produces more pronounced motor weakness, with potential for complete paralysis of affected muscles (grade 0-2/5 strength) 5, 6
• Patients with severe deficits (≤ grade 3/5 weakness) have less than 50% chance of complete recovery even with treatment 6
• Numbness or tingling predicts longer recovery times 6

Common Pitfalls to Avoid

1. Do not assume bilateral symptoms or hand dysfunction are from foraminal narrowing alone - these indicate cord compression requiring different imaging interpretation and management 7, 8

2. Do not overlook C3/C4 foraminal stenosis - while less commonly symptomatic than C5-C6 or C6-C7, significant narrowing at these levels can produce shoulder and upper arm symptoms 1

3. Distinguish radicular pain from referred pain - true radiculopathy follows dermatomal patterns with associated motor/sensory deficits, not just diffuse neck and shoulder pain 1, 3

4. Correlate imaging with clinical examination - degenerative changes and foraminal narrowing are common in asymptomatic individuals over 30 years; symptoms must match the anatomical level 8