M1 Axilla/Brachial Plexus/Arm/Forearm Preformative Review Quiz

A 27-year-old man was brought to the emergency department after he was involved in a motor vehicle collision. An x-ray of the right shoulder shows a fracture of the lateral border of the scapula. Six weeks later, the patient comes to the physician because of pain and weakness in the right shoulder while performing his daily activities. Physical examination shows weakness and pain on medial rotation and adduction of the humerus. Which of the following nerves is most likely injured? 

A 55-year-old man comes to the physician after receiving a blunt trauma to his right axilla during a fall. He has difficulty elevating the right arm above the level of his shoulder. Physical examination shows the inferior angle of his right scapula protrudes more than the lower part of the left scapula. The protrusion is more prominent when the patient pushes against a wall. Which of the following neural structures is most likely injured?

A 28-year-old nulligravida woman gives birth to a 3500 g (7 lb 11 oz) baby boy by forceps delivery. The pregnancy was complicated by gestational diabetes. Physical examination of the neonate finds an adducted, medially rotated left arm that is flexed at the wrist. Which part of the brachial plexus was most likely injured during the delivery? 

A 19-year-old man is brought to the emergency department after falling painfully onto his right shoulder in a soccer game. A diagnosis of a dislocated right shoulder is made. After reduction of the shoulder dislocation, he has persistent pain over the dorsal region of the shoulder. Physical examination shows no obvious bone deformities but he is unable to abduct the arm normally. A magnetic resonance imaging (MRI) of the shoulder shows a torn muscle. Which of the following muscles is most likely damaged by this injury?

A 32-year-old man comes to the physician because of a 3-day history of right shoulder pain after taking part in a tennis competition. An MRI in the oblique sagittal plane shows thickening and hypertrophy of a shoulder ligament. The physician explains that over the years of playing tennis, a shoulder ligament has gradually caused severe damage to the underlying muscle. Which of the following ligaments is the physician most likely referring to? 

A 25-year-old man is brought to the emergency department because of excruciating pain in his right shoulder and proximal arm after a wrestling match. Physical examination shows that the arm is slightly abducted and externally rotated. The patient resists when passive medial rotation is attempted. Radial pulses are palpated bilaterally. An x-ray of the shoulder shows a dislocation of the humerus at the glenohumeral joint. Which of the following is the most likely mechanism of injury? 

A 29-year-old woman is brought to the emergency department 2 hours after falling from her balcony. Physical examination shows noticeable swelling and bruising over the clavicle. There is tenderness, crepitus on palpation, and decreased range of motion of her left upper limb. An x-ray of the left shoulder shows a fracture of the clavicle and internal bleeding is strongly suspected. Which of the following vessels is most likely to be injured in a clavicular fracture? 

A 34-year-old woman is brought to the emergency department with left shoulder pain for 2 hours after she struck a tree on a ski slope. Physical examination shows swelling and bruising of the left shoulder. The patent has tenderness to palpation and a “step-off” of the left clavicle is noted. An x-ray shows a high-grade left shoulder separation. Which of the following typically occurs in this type of injury?

A 56-year-old woman is brought to the emergency department after being involved in a motor vehicle collision. A large area of her anterior chest wall needed to be surgically removed and replaced with a musculo-osseous scapular graft involving the medial border of the scapula. Which of the following arteries will most likely compensate for the blood supply to the entire scapula?

A 25-year-old man is brought to the emergency department because he fell on a slippery trail and injured his right upper limb. Physical examination shows abrasions over his triceps brachii muscle. Which of the following nerves innervates the triceps brachii muscle?

A 24-year old woman is brought to the emergency department after she slipped on wet pavement and fell against the curb, injuring her right arm. Physical examination shows loss of sensation of the posterior forearm and dorsal hand. An x-ray of the right upper limb shows a mid-body fracture of the humerus. Which pair of structures is most likely injured at the fracture site?

A 20 year old man is brought to the emergency department after a motorbike collision. He is awake, alert, and oriented and his vital signs are within normal limits. Physical examination shows several cuts and bruises on his body. He is unable to extend the left wrist. Extension of the elbow is normal bilaterally. Sensation is lost in the lateral half of the dorsum of the left hand. Which of the following nerves is most likely injured, and in what part of the arm is the injury located?

A 27-year-old man is brought to the emergency department because of pain and swelling of his right arm after falling from a ladder. He is unable to abduct his right arm more than 15 degrees and resists lateral rotation due to pain. The patient also has a loss of sensation over the right shoulder. An x-ray of the arm shows an oblique fracture of the humerus. The most likely cause of these symptoms is a fracture affecting which of the following locations?