USMLE Anatomy Question Base

A 75-year-old man with a 40-pack.year history of Smoking and hypercholesterolemia is diagnosed with severe atherosclerosis. Atherosclerotic occlusion of which of the following arteries would result in insufficient perfusion of the urinary bladder ?

A 36-year-old woman ts hospitalized for treatment of a stomach ulcer that has been getting  progressively worse over several months. Radiographic studies reveal the site of involvement  to be along the greater curvature. approximately 4 cm away iron, the pyloric sphincter. That night, Me ulcer perforates, and there is considerable, intra-abdominal bleeding. Surgery reveals  that the ulcer has eroded through the stomach wall and has damaged the rtery supplying the involved region of the stomach. Which artery was likely involved?

A woman who recently gave birth has elevated prolasl in levels The gland responsible for secretion of this hormone is derived from which of the hallowing structures?

A 49 year old Vietnamese man is diagnosed with tuberculosis. On physical examination, large flocculent masses are noted over the lateral lumbar back, and a similar mass is located in the ipsilateral groin just medial to the anterior superior iliac spine. This pattern of involvement strongly suggests an abscess tracking along which of the following muscles?

A 24 year old man is stabbed in the neck. Neurologic examination reveals left-sided hemiparesis.  There is complete loss of discriminatory joint position and vibration sensation below C8 on the  left side. On the right side, there is loss of pain and temperature sensation below C8. It can be expected that an MRI of the cervical spinal cord will show which of the following findings?

A 2 year old boy is brought to the pediatrician by his mother because he has had several episodes of rectal bleeding. Evaluation with a technetium-99m perfusion scan reveals a 3cm ileal outpouching located 60 cm from the ileocecal value. This structure most likely contains which of the following types of ectopic tissue?

A 34 year old man is examined in the prison infirmary after sustaining a superficial stab wound to the superolateral aspect of the thoracic wall at the level of the third rib. There is little bleeding and no difficulty breathing; However, the medical boarder of the scapula on the injured side pulls away from the body wall when the arm is raised . In addition, the arm cannot be abducted above the horizontal. Which of the following muscles is paralyzed?

A histologist is examinig cells arrested at various stages of oogenesis. He discovers a follicle whitin the stroma of the ovary that has developed an antrum. This follicle would be classified as :

A 54 year old man has cirrhosis, with obstruction of the portal circulation within the liver. Portal  blood could still be conveyed to the caval system via which of the following ?

A 47 year old man presents to his neurologist with an unsteady, broad-based gait and slow, slurred speech. Neurologic examination reveals dysdiadochokinesia, intention tremor, hypotonia, and nystagmus. The patient’s lesion is in a brain structure that derives from which of the following embroyonic structures?

A 47-year-old woman with a history of rheumatic fever is examined by her physician. Physical examination is significant for a low-pitched, rumbling, diastolic mur­mur preceded by an opening snap. The affected valve can be best evaluated by auscultation at which of the following locations?

A patient has a tumor in the pterygopalatine fossa. The tumor is enlarging and moving through the pterygo­maxillary fissure. The tumor is entering what region of the skull?

A neuroscientist decides to perform a study that requires him to increase the concentration of norepinephrine in the cortex of an animal subject. He does this by electri­cally stimulating a nucleus in the brain. Which of the following nuclei is the most important source of norad­renergic innervation to the cerebral cortex?

A surgeon tells a medical student to tap the side of the face of a patient who just had thyroid surgery. The surgeon is most worried about damage to which of the following vessels?

A 45-year-old man comes into the emergency department with abdominal pain that has progressively worsened since the previous night. He also notes nausea and vomiting, but is afebrile. Upper gastrointestinal radiographic studies reveal that a loop of small intestine has passed through the epiploic foramen into the omental bursa and is constricted by the margins of the foramen as the intestine fills. The constriction should not be surgically relieved by opening the epiploic foramen because this procedure would risk cutting the

A 26-year-old man is stabbed in the left chest during a bar brawl. Several days after he is treated, he returns to the physician complaining of decreased function in his left arm. Physical examination reveals a winged left scapula and an inability to raise his left arm above the horizontal. Which of the following nerves is most likely affected?

A patient is transported to the emergency department with a knife wound to the right fifth intercostal space at the midaxillary line. Which of the following structures is likely to have been damaged?

A couple comes to the physician for advice about contraception and family planning. The physician provides advice about various methods of birth control. While discussing the option of using an intrauterine device. a discussion of the process of implantation comes up. At what stage of embryonic development does an embryo normally begin to implant in the endometrium?

A newborn male is found to have urethral openings along the ventral surface of the penis. The physician explains to the parents that the bilateral structures that should have fused in the midline failed to fuse completely, and this resulted in the defect. The parents are very concerned. but the physician reassures them that this can easily be surgically corrected. Which of the following structures in a female normally develop from the same structures that failed to fuse in this boy?

A 19 year old woman comes to the emergency department after falling while on roller-blades. There is a 3 cm laceration over the lateral aspect of the knee penetration so deep that the head of the fibula is apparent. A radiograph of the leg is negative for any fractures. A noticeable foot-drop occurs while the patient walks. Further examination reveals inability to dorsiflex or evert of the foot. Which of the following best explains her injury?

A resident physician is performing a pelvic examination on a young woman. The fingers of one of her hands are in the patient’s vagina, palpating the cervix. The other hand is pressing on the abdomen. With the palm of this hand, the physician feels a bony structure in the lower midline. This structure is most likely the

A 45-year-old man with a history of stable angina presents to the emergency department with an episode of chest pain that is not relieved by rest or nitroglycerin. After stabilization in the telemetry unit for 2 days, he undergoes a thallium stress test. The results show reduced perfusion of the lateral wall of the left ventricle. Which artery is most likely occluded?

A patient presents with sudden onset of violent involuntary flinging movements of the left upper limb. The movements are jerky and irregular. This patient’s condition can best be described as a loss of:

A 4-day-old boy is brought to the pediatric clinic because of breathing difficulties and poor feeding. He coughs, chokes, and spits up milk very soon after beginning to suckle. Physical examination and radiographs reveal the presence of the most common type of tracheoesophageal fistula. The infant’s defect likely resulted from

A 40-year-old man complains of loss of sensation over the right scrotum and on the medial right thigh. Damage to which of the following nerves would result in such symptoms?

A neonate has a prominent defect at the base of his spine through which his meninges and spinal cord protrude. A failure of which of the following processes is the most common cause of this type of defect?

A surgeon is first on the scene after a serious automobile accident. He finds a passenger bleeding profusely from the neck and correctly surmises that the bleeding is from the carotid artery. To control the bleeding, the surgeon can compress the carotid artery against the anterior tubercle of which of the following vertebrae?

An intravenous pyclogram is performed on a patient to evaluate the function and structure of her kidneys. Examination of the resulting radiographs reveals that the left kidney is normal but that there is a duplication of the ureter and renal pelvis on the right side. Further testing reveals that kidney function is normal. This variation is a result of abnormal development of which of the following structures?

MRI reveals that a 62-year-old man has a brain tumor growing in his interhemispheric fissure at the level of the central sulcus. The tumor produces neurologic dysfunction of the cerebral cortex on either side of the tumor. A neurologic examination of this patient would most likely reveal

Brunner’s glands secrete an alkaline product that helps achieve optimal pH for the activity of pancreatic enzymes. Where are these glands located?

A 24-year-old man presents with pain in his right wrist that resulted when he fell hard on his outstretched hand. Radiographic studies indicate an anterior dislocation of a proximal row carpal bone that articulates with the most lateral proximal row carpal bone. Which of the following bones was dislocated?

The femoral triangle is bounded superiorly by the inguinal ligament. Which of the following structures form the lateral and medial borders of the femoral triangle?

A 43-year-old woman is diagnosed with a condition that causes excruciating pain near her nose and mouth. The involved nerve innervates which of the following branchial arches?

An infant is born with an abnormally developed falciform ligament. The hepatogastric and hepatoduodenal ligaments are also malformed. These developmental anomalies are most likely due to abnormal development of the

An autopsy is performed on a man who died of an unknown cause. The pathologist discovers that the man lids a small atrial septa! defect. The defect is seen in the portion of the atrial septum near the upper border of the fossa ovalis. Which of the following was the likely functional manifestation of this defect during life?

A 6-year-old boy is brought to the office for evaluation of a neck mass. His mother reports that he first developed the mass 3 days ago, and it has not resolved. Further questioning reveals that he has recently recovered from a viral upper respiratory infection. He is otherwise healthy and is up to Gate on all recommended vaccinations. Physical examination shows a 2-cm neck mass in the midline immediately above the thyroid cartilage notch. The mass elevates when he sticks his tongue out of his mouth. Which of the following is the most likely diagnosis?

When removing an impacted mandibular third molar, the oral surgeon must warn the patient of possible lasting numbness of the tip of the tongue. This loss of general sensation is due to damage to the

A resident physician is demonstrating tire correct technique for inserting a subclavian central venous line. He has a medical student palpate the clavicle, then the chest wall below it. The first bonystructurc that can be palpated below the inferior margin of the medial portion of the clavicle is the

A 34-year-old woman bursts through the doors of the emergency department. She is straining to take a breath but can only mouth the phrase: “I can’t br—” before collapsing. She is placed on a stretcher. Her tongue is swollen and protruding from her mouth. ‘the patient has only minimal air movement with bag-mask ventilation. Oxygen saturation is approximately 80%. Attempts at oral intubation are unsuccessful due to massive soft tissue edema of her pharynx. A decision is made to perform a cricothyrotomy. The necessary instrument tray is collected, and the patient’s neck is quickly prepped. After palpating the neck to identify the appropriate landmarks, an incision should be made at which of the following locations?

Air infant born to an alcoholic mother had microcephaly and cardiac abnormalities and died despite resuscitative efforts. During which of the following periods of pregnancy is alcohol most teratogenic?

A 15-year-old girl with a history of chronic rlrinitis, allergy, asthma, and nasal polyposis presents with fever and dental pain. She is diagnosed with maxillary sinusitis. Mucopurulent exudate would be most likely to drain through an ostium in the

A patient presents to the physician complaining of “something wrong with her foot” that causes her to trip and fall. Physical examination reveals an inability to dorsiflex (extend) the foot and a loss of sensation between the first and second toes. There is no other motor or sensory loss. Which of the following nerves was most likely injured?

During a routine physical examination, a 71 -year-old man is found to have a 7-cm pulsatile mass deep in the abdomen, between the xiphoid and the umbilicus. He has a history of untreated hypertension. The endothelial lining of the affected structure is composed of which of the following tissue types?

One week following a sexual encounter at a ski resort in Colorado, a young woman develops a painful, swollen knee joint. The emergency department physician suspects gonococcal arthritis and wants to confirm this by sending joint fluid for bacterial culture. lie uses the standard suprapatellar approach and passes a needle from the lateral aspect of the thigh into the region immediately proximal to the patella. Through which of the following muscles does the needle pass?

A 67-year-old man has an abnormal neurologic exam. An electroencephalogram is subsequently performed and reveals delta waves over his left frontal lobe. Which of the following was the most likely abnormal finding on his neurologic exam?

A 23-year-old woman wearing high-heeled shoes inverts and sprains her ankle while running down a Bight of stairs. Which of the following ligaments did she most likely injure?

A surgeon performing an appendectomy makes an incision through the ventrolateral abdominal wall. The layers of the abdominal wall are shown below
            1. Internal oblique
           2. External oblique
          3. Peritoneum
         4. Transversus abdominis
Which of the following corresponds to the order of penetration of the layers of the abdominal wall ?

A 49-year-old woman comes to the emergency department because of right upper quadrant pain, nausea, vomiting, and fever. She also complains of pain in her right shoulder. A right upper quadrant ultrasound reveals multiple gallstones and pericholecystic fluid. Which of the following dermatomes is most likely involved in her shoulder pain?

A 57-year-old man has hematuria and left-sided flank pain. Diagnostic studies show a left-sided renal mass with extension into the renal vein. A radical nephrectomy is performed, and the specimen is sent for pathologieevaluation. Which of the following structures present in this patient’s specimen is lined with epithelium derived from mesoderm of the ureteric bud?