Common innervation of the heart that often causes referred pain refers to which structures?

• A. Hip and knee
• B. Lower back
• C. Fingers
• D. Jaw, neck, diaphragm, and shoulder

Answer: (D)

When heart-related pain is detected, it often travels with visceral sensory fibers that ride along the sympathetic pathways to the upper thoracic spinal levels. The brain then misinterprets that input as coming from somatic structures served by those same levels, producing referred pain. This pattern explains why cardiac issues are commonly felt in the jaw, neck, shoulder, and in the diaphragm area via the phrenic nerve. So the structures most often involved in referred cardiac pain are the jaw, neck, diaphragm, and shoulder.