In cases of liver trauma, where might pain manifest according to Kehr's sign?

In cases of liver trauma, pain can manifest in the right shoulder according to Kehr's sign. This phenomenon occurs due to diaphragmatic irritation caused by blood or fluid accumulation in the peritoneal cavity, which can irritate the phrenic nerve that supplies the diaphragm. The phrenic nerve originates from cervical nerve roots C3, C4, and C5, and its irritation can lead to referred pain felt in the shoulder region.

This reflects the body's interconnected neural pathways, where visceral pain from internal organs can sometimes be felt in more distant anatomical locations. In the case of liver trauma, if bleeding or injury leads to irritation of the diaphragm, the patient may experience pain specifically in the right shoulder — an important consideration for paramedics when evaluating potential internal injuries in trauma patients.