- Referred pain: pain of visceral origin (heart, diaphragm) perceived in a somatic area sharing the same spinal cord segments as the organ's own sensory pathway.
Cause, Route and Site of Referred Pain
Differences between referred pain from the heart and the diaphragm
Point
Cause
- Heart
- Ischemia of the heart
- Diaphragm
- Irritation secondary to peritonitis
Nerve carrying the pain
- Heart
- Sympathetic fibers (cervical and thoracic ganglia)
- Diaphragm
- Phrenic nerve
Spinal segments (root value)
- Heart
- T1 to T5
- Diaphragm
- C3, C4, C5
Site of referred pain
- Heart
- Pectoral region, medial aspect of arm and forearm
- Diaphragm
- Tip of the shoulder
Nerve supplying referred site
- Heart
- T1 to T5 spinal nerves
- Diaphragm
- Supraclavicular nerve (C3, C4, C5)