A 30-year-old man has right iliac fossa pain suggestive of acute appendicitis. On examination, pain is reproduced by slow passive extension of the right hip at the joint while the patient lies supine. This finding indicates irritation of which muscle?

• A Obturator internus
• B Gluteus medius
• C Rectus femoris
• D Iliopsoas ✓

Explanation

Passive hip extension stretches the iliopsoas, reproducing pain when the inflamed retrocaecal or retroileal appendix lies against that muscle; this is the psoas sign. Flexion plus internal rotation of the hip tests the obturator internus (obturator sign), which points to a pelvic appendix. The discriminating fact is the direction of movement: extension stresses psoas, rotation stresses obturator.

Reference: Bailey and Love's Short Practice of Surgery, 27th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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