WBR0941

Author	PageAuthor::William J Gibson
Exam Type	ExamType::USMLE Step 1
Main Category	MainCategory::Anatomy
Sub Category	SubCategory::Gastrointestinal
Prompt	[[Prompt::A 70-year-old man presents to his primary care physician for a bulge in his right groin that becomes more prominent with coughing. Ultrasound of the region reveals a hernia that protrudes medial to the inferior epigastric vessels and laterally from the rectus abdominus. The inferior border of this hernia is bounded by a tissue formed from the aponeurosis of which of the following?]]
Answer A	AnswerA::Internal abdominal oblique
Answer A Explanation	[[AnswerAExp::Incorrect: The internal abdominal oblique lies deep to the external abdominal oblique and superficial to the transversus. It is responsible for rotation and side-bending of the trunk. In males, the cremaster muscle is attached to the internal abdominal oblique.]]
Answer B	AnswerB::External abdominal oblique
Answer B Explanation	AnswerBExp::Correct: The aponeurosis of the external abdominal oblique gives rise to the inguinal ligament.
Answer C	AnswerC::Transversus abdominus
Answer C Explanation	AnswerCExp::Incorrect: The transversus abdominis, so called for the direction of its fibers, is the innermost of the flat muscles of the abdomen, being placed immediately beneath the internal oblique muscle. Its aponeurosis gives rise to the line alba.
Answer D	AnswerD::Linea alba
Answer D Explanation	AnswerDExp::Incorrect: The linea alba is the fibrous band that runs down the midline of the abdomen atop the rectus abdominus.
Answer E	AnswerE::Spermatic cord
Answer E Explanation	AnswerEExp::Incorrect: The spermatic cord travels through the inguinal canal, which is not equivalent to the inguinal ligament.
Right Answer	RightAnswer::B
Explanation	[[Explanation::The patient in this vignette has a direct hernia, in which the contents of the abdomen protrude through a weakend area in the transversalis fascia. This region lies superior to the inguinal ligament, medial to the epigastric vessels and lateral to the rectus abdominus. It is often referred to as Hesselbach’s triangle. These hernias are capable of exiting via the superficial inguinal ring but, unlike indirect inguinal hernias, they cannot move into the scrotum. Direct inguinal hernias are occur 10x more often in males than females. Educational Objective: The aponeurosis of the external abdominal oblique gives rise to the inguinal ligament. References: First Aid 2013 page 316 Educational Objective: References: ]]
Approved	Approved::Yes
Keyword	WBRKeyword::Abdomen, WBRKeyword::Anatomy, WBRKeyword::Inguinal, WBRKeyword::Ligament, WBRKeyword::Hernia
Linked Question	Linked::
Order in Linked Questions	LinkedOrder::