Nerve most commonly injured in Mac Burneys incision –
**Core Concept**
The MacBurney's incision is a surgical approach used in the right lower quadrant of the abdomen, typically for appendectomies. The incision involves cutting through layers of skin, subcutaneous tissue, and muscle to access the cecum. However, this incision poses a risk to nearby structures, particularly nerves that supply the abdominal wall.
**Why the Correct Answer is Right**
The nerve most commonly injured in MacBurney's incision is the ilioinguinal nerve. This nerve arises from the L1 spinal nerve and supplies the skin of the upper medial thigh, the root of the penis, and the upper part of the scrotum in males, or the mons pubis and the labia majora in females. The ilioinguinal nerve runs along the inguinal ligament and is located superficially, making it vulnerable to injury during the incision. Damage to this nerve can result in sensory loss and pain in the distribution of the nerve.
**Why Each Wrong Option is Incorrect**
**Option A:** The iliohypogastric nerve is another nerve that runs through the abdominal wall but is not as commonly injured in MacBurney's incision. It supplies the abdominal skin and is located deeper than the ilioinguinal nerve.
**Option B:** The obturator nerve is not typically at risk during MacBurney's incision. It supplies the medial thigh muscles and is located more medially in the pelvis.
**Option C:** The femoral nerve is not commonly injured in MacBurney's incision. It supplies the anterior thigh muscles and is located more distally in the thigh.
**Clinical Pearl / High-Yield Fact**
In abdominal surgery, it's essential to identify and preserve the ilioinguinal nerve to prevent postoperative pain and sensory disturbances.
**Correct Answer: D. Ilioinguinal nerve**