03/09/2026
🧠Cervical Nerve Root Assessment – Focus on C7 (C4–T1 Overview)
This image highlights the cervical spine levels (C4–T1) and demonstrates how a specific nerve root—primarily C7—relates to motor function, reflex testing, and sensory distribution in the upper limb.
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📍 Spinal Level Shown
The diagram centers on C7, located between C6 and T1.
C7 is one of the most commonly affected nerve roots in cervical disc herniation.
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🔹 Motor Function (Myotome)
The image shows wrist flexion as a key motor function.
C7 contributes to:
• Wrist flexors
• Triceps (elbow extension)
• Finger extensors
👉 Weak wrist flexion or elbow extension may suggest C7 involvement.
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🔹 Reflex
Triceps tendon reflex is highlighted.
• Reduced or absent triceps reflex → possible C7 radiculopathy
Reflex testing helps confirm neurological level involvement.
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🔹 Sensory Distribution (Dermatome)
The sensory map shows:
• C7 dermatome → middle finger region
• Surrounding levels (C5, C6, C8, T1) also displayed for comparison
👉 Numbness or tingling in the middle finger is a classic C7 sign.
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🔎 Clinical Importance
Cervical disc herniation at C6–C7 can compress the C7 nerve root, causing:
• Neck pain radiating down the arm
• Middle finger numbness
• Triceps weakness
• Reduced triceps reflex
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🦴 Key Takeaway
To localize a cervical nerve problem, assess:
âś” Motor strength
âś” Reflex changes
âś” Dermatomal sensation
Combining all three provides accurate neurological diagnosis.