Forearm and Hand

Extensor carpi radialis longus is the correct answer. In tennis elbow there is a tear in the Common Extensor Tendon that originates at the lateral epicondyle. The one muscle out of the group that is not part of the common extensor tendon and originates at the lateral supracondylar ridge is the extensor carpi radialis longus.

A 31-year-old male patient arrived at the Emergency Department reporting that he had just finished playing an intense game of tennis and is now experiencing severe pain on the lateral aspect of his right elbow. Which of the following muscles would not be affected? Extensor carpi radialis longus Extensor carpi ulnaris Extensor carpi radialis brevis Extensor digitorum Extensor digiti minimi

Hyperflexion at DIP and inability to extend at DIP is the correct answer. Mallet finger is also known as baseball finger. It presents as hyperflexion at DIP and inability to extend at DIP. Mallet finger is caused by long extensor tendon avulsion.

Question 10 1 / 1 pts A 28-year-old male baseball player was injured while sliding into second base. When he got up, he realized that his finger was swollen due its impact with the base. He was diagnosed with Mallet finger. How does this finger present? Hyperextension at DIP and inability to flex at DIP Hyperflexion at DIP and inability to extend at DIP Inability to flex at DIP and Extension at PIP Inability to extend at DIP and hyperextension at DIP Extension at DIP and Flexion at PIP

Paralysis of adductor pollicis muscle is the correct answer. Adductor pollicis muscle is innervated by ulnar nerve. Therefore, a damage to median nerve will not result in the paralysis of this muscle. Rest of the incorrect answers have characteristics of motor and sensory innervations of median nerve.

Question 11 1 / 1 pts Damage to the median nerve at the level of flexor retinaculum will result in all the following except: Ape hand Paralysis of adductor pollicis muscle Paralysis of lumbricals (the most lateral two) Loss of sensation to middle finger (palmar aspect) Loss of sensation to the lateral ½ of the ring finger in the nail bed

Correct answers: Hamate. These symptoms are due to an ulnar nerve palsy. The ulnar nerve runs within the Guyon's canal which is made up of a ligament running between the hamate and pisiform bone. Thus, a fracture of the hamate bone (Answer E) will cause ulnar palsy symptoms.

Question 12 1 / 1 pts A 44-year-old female mechanic complains of pain on her right hand. The strength in her hand is graded a 5 but there is tingling feeling in her 4th and 5th digits. Two weeks ago, a hammer fell off the shelf and landed on her medial wrist. Fracture of what bone will cause these symptoms? Scaphoid Capitate Hamate Ulnar Lunate

Correct answer: Distal part of radius displaced dorsally; proximal part displaced ventrally. The distal part of the radius is separated and overrides the proximal part, displacing dorsally and creating the characteristic dinner fork appearance.

Question 13 1 / 1 pts A 49-year-old male has slipped getting out of the shower and they have a fracture of the distal radius. A radiograph reveals it to be a classic Colles fracture. What is the disposition of the two parts of the radius? Distal part of radius displaced dorsally; proximal part displaced ventrally Distal part of radius displaced ventrally; proximal part displaced ventrally Distal part of radius displaced ventrally; proximal part displaced Distal part of radius displaced dorsally; proximal part displaced dorsally

superficial branch of ulnar nerve is the correct answer. The fifth digit along with medial half of the fourth are superficial branch of ulnar nerve.

Question 14 1 / 1 pts Sensory innervation to the medial half of digit four is provided by: Superficial branch of ulnar nerve Radial nerve Deep branch of ulnar nerve Deep branch of median nerve Digital branch of median nerve

Correct answers: Deep branch of the ulnar nerve; recurrent branch of the median nerve. Opposition of the 1st and 5th digits (bringing the thumb and pinky together) is performed by the opponens pollicis and opponens digiti minimi. Since this function is lost, it is safe to assume that the opponens pollicis (innervated by the recurrent branch of the median nerve) and the opponens digiti minimi (innervated by the deep branch of the ulnar nerve).

Question 15 1 / 1 pts A 15-year-old girl accidentally cuts herself on the palm of her right hand while cutting up vegetables during cooking. After cleaning up the wound, she realizes she is not able to bring her thumb and fifth right digit (pinky) together. Which two nerves are associated with the muscle's opposition of the 1st and 5th fingers in the hand? Deep branch of the ulnar nerve Recurrent branch of the median nerve Palmar branch of the ulnar nerve Palmar cutaneous branch of the median nerve

Lateral aspect of the dorsum of the hand is the correct answer. Fracture of the shaft of the humerus may lead to damage to the radial nerve, which runs in the radial groove of the humerus. Radial nerve supplies cutaneous innervation to most of the dorsum of the hand, except for the distal portions of the fingers and medial one and the half digits. Distal portions of the fingers on the lateral aspect are innervated by the median nerve. Medial one and one-half digits are innervated by the ulnar nerve, both on the palmar and dorsal surfaces.

Question 16 1 / 1 pts A fracture of the shaft of the humerus results in the loss of cutaneous sensation to which of the following areas? Lateral aspect of the dorsum of the hand Medial aspect of the arm Lateral aspect of the palmar surface of the hand Lateral aspect of the forearm Medial one and one-half digits

Deep branch of the ulnar nerve is the correct answer. All the interossei muscles are innervated by the same nerve.

Question 17 1 / 1 pts Dorsal interossei muscles of the hand innervated by? Digital branch of the median nerve Deep branch of the ulnar nerve Deep branch of the median nerve Deep branch of the radial nerve

Medial tendons of flexor digitorum profundus and flexor carpi ulnaris is the correct answer. The flexor carpi ulnaris and the medial two tendons of the flexor digitorum profundus are supplied by the ulnar nerve. All other muscles of the anterior forearm are supplied by the median nerve.

Question 18 1 / 1 pts Ulnar nerve damage would lead to loss of motor functions to which muscle(s) in the forearm? Lateral tendons of flexor digitorum profundus and flexor pollicis longus Medial tendons of flexor digitorum profundus and flexor carpi ulnaris Lateral tendons of flexor digitorum superficialis and flexor carpi ulnaris Medial tendons of flexor digitorum superficialis and flexor pollicis longus

Mid-shaft is the correct answer. A mid-shaft fracture of the humerus will most likely damage the radial nerve which supplies the extensors of the forearm. The options surgical neck and anatomical neck would most likely cause damage to the axillary nerve and the choice supracondylar ridge would most likely cause damage to the median nerve.

Question 19 1 / 1 pts A patient comes into your office and is presenting with arm pain and weak extension at the wrist. An x-ray of the arm is taken, and a fracture of the humerus is evident. Where is the most probable location of the fracture in this patient? Surgical neck Supracondylar ridge Anatomical neck Mid-shaft

Flexor digitorum profundus is the correct answer. The origin of this muscle is the proximal surface of medial ulna and the anterior surface of the ulna, and interosseous membrane.

Question 2 1 / 1 pts Which of the following muscles does not have an origin at the medial epicondyle? Pronator teres Flexor carpi radialis Flexor carpi ulnaris Flexor digitorum superficialis Flexor digitorum profundus

Loss of wrist extension leading to wrist drop is the correct answer. Damage to the radial nerve leads to inability to extend wrist and fingers (MCP, PIP, DIP joints). The wrist remains partly flexes due to unopposed flexor tone and gravity.

Question 20 1 / 1 pts A 16-year-old boy fell from a motorcycle, and his radial nerve was severely damaged due to a fracture of the midshaft of the humerus. Which of the following most likely result from this accident? Inability to oppose the thumb Weakness in pronating the forearm Inability to abduct the fingers. Sensory loss over the ventral aspect of the base of the thumb Loss of wrist extension leading to wrist drop

Pronator teres is the correct answer. The 8 muscles of the anterior compartment of the forearm include: pronator teres, flexor carpi radialis, palmaris longus, flexor carpi ulnaris, flexor digitorum superficialis, flexor digitorum profundus, flexor pollicis longus, pronator quadratus.

Question 3 1 / 1 pts Your friend is interested in learning more about anatomy. She asks you to name a muscle in the anterior compartment of her forearm. Which of the following muscles would you mention? Pronator teres Supinator Extensor indicis Abductor pollicis longus Brachioradialis

Abductor pollicis longus is the correct answer.

Question 4 1 / 1 pts While preforming a delicate surgery within a patient's anatomical snuff box, your attending accidentally severs the tendon to the extensor pollicis brevis and a tendon positioned immediately anterior to this tendon. What is the other muscle associated with this tendon which was most likely severed? Abductor pollicis longus Adductor pollicis longus Extensor carpi radialis longus Extensor indicis Extensor pollicis longus Extensor carpi radialis brevis

(i) Flexor digitorum profundus; (ii) Median nerve is the correct answer. Flexion of the distal IP joint is mainly under the control of the Flexor digitorum profundus. Remember that this muscle had dual innervation, digits 2 and 3 are controlled by the Median nerve, while digits 4 and 5 are controlled by the Ulnar nerve.

Question 5 1 / 1 pts A 27-year-old male patient presents to your clinic complaining of pain in the forearm. He tells you that while he was lifting weights, he felt a painful, tearing sensation in his right hand. On physical examination, the patient can flex his metacarpophalangeal (MCP) joints on digits 2-5. Next you immobilize his proximal interphalangeal (IP) joint and have him flex digits 2-5. During the test you notice that he is unable to flex his index finger and middle finger at the distal interphalangeal (IP) joint. (i) What muscle are you concerned about and (ii) what is the innervation? (i) Flexor carpi radialis; (ii) Median nerve (i) Flexor digitorum profundus; (ii) Median nerve (i) Flexor digitorum superficialis; (ii) Median nerve (i) Flexor carpi ulnaris; (ii) Ulnar nerve (i) Flexor digitorum profundus; (ii) Ulnar nerve (i) Palmaris longus; (ii) Median nerve

Ulnar nerve and medial epicondyle are the correct answers. The ulnar nerve passes posterior to the medial epicondyle, leaving it precariously exposed and causing pain when struck.

Question 6 1 / 1 pts A second semester medical student knocks his elbow on the car door hitting his "funny bone" and lets out a scream. Sitting in pain he recalls the structures involved with the pain and its anatomical landmark. (a) Which structure did the student recall, and (b) posterior to which anatomical bony landmark is it located? (a) Median nerve; (b) medial epicondyle (a)Ulnar nerve; (b) lateral epicondyle (a) Ulnar nerve; (b) medial epicondyle (a) Radial nerve b) medial epicondyle (a) Median nerve; (b) lateral epicondyle (a) Radial nerve; (b) lateral epicondyle

Adductor Pollicis is the correct answer. The adductor pollicis is innervated by the ulnar nerve.

Question 7 1 / 1 pts Which intrinsic muscle of the hand is not innervated by the median nerve? 1st and 2nd lumbricals Adductor Pollicis Flexor Pollicis brevis Opponens Pollicis

Correct answers: (a) Flexor carpi ulnaris and medial half of flexor digitorum profundus, (b) ulnar nerve are the correct answers. Ulnar nerve supplies the flexor carpi ulnaris and the medial half (digits 4 and 5) of flexor digitorum profundus in the anterior forearm.

Question 8 1 / 1 pts The median nerve supplies all the muscles of the anterior forearm except two. (a) Which two muscles of the anterior forearm are not supplied by the median nerve, and (b) which nerve are they supplied by? (a) Flexor carpi ulnaris and medial half of flexor digitorum superficialis, (b) ulnar nerve (a) Flexor pollicis longus and medial half of flexor digitorum profundus, (b) ulnar nerve (a) Flexor pollicis longus and medial half of flexor digitorum profundus, (b) radial nerve (a) Flexor pollicis longus and medial half of flexor digitorum superficialis, (b) ulnar nerve (a) Flexor carpi ulnaris and medial half of flexor digitorum superficialis, (b) radial nerve (a) Flexor carpi ulnaris and medial half of flexor digitorum profundus, (b) ulnar nerve (a) Flexor pollicis longus and medial half of flexor digitorum superficialis, (b) radial nerve (a) Flexor carpi ulnaris and medial half of flexor digitorum profundus, (b) radial nerve

Hamate is the correct answer. Losing sensation to the medial 4th digit points towards Ulnar nerve damage. The Ulnar nerve is damaged when the hamate bone is fractured.

Question 9 1 / 1 pts A 43-year-old male fell on his hand and visited the doctor for a checkup. During a sensation test, the doctor noticed that the patient had lost sensation to the medial half of the 4th digit. The doctor suspected a carpal bone fracture. What bone was fractured? Hamate Pisiform Capitate Trapezium Triquetrum Scaphoid Lunate Trapezoid