Psoas sign Video:
The psoas sign is a medical sign that indicates irritation to the iliopsoas group of hip flexors in the abdomen, and consequently indicates that the inflamed appendix is retrocaecal in orientation (as the iliopsoas muscle is retroperitoneal). It is one of the physical examinations that aids in diagnosis acute appendicitis. Other physical examinations include the Obturator’s sign and Rovsing’s sign. Please watch the following Psoas sign video.
The pain results because the psoas borders the peritoneal cavity, so stretching (by hyperextension at the hip) or contraction (by flexion of the hip) of the muscles causes friction against nearby inflamed tissues. In particular, the right iliopsoas muscle lies under the appendix when the patient is supine, so a positive psoas sign on the right may suggest appendicitis.
A positive psoas sign may also be present in a patient with a psoas abscess. It may also be positive with other sources of retroperitoneal irritation, e.g. as caused by hemorrhage of an iliac vessel.
References for Psoas Sign:
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