MSP (ANATOMY) – PROBLEM SET #3, 2ND QUARTER
1. A 35 year old man comes into your colleague’s office because of an abscess on the thenar eminence of his left hand. Your colleague (a graduate from the USC School of Medicine) knows that he needs to drain the abscess so that it can heal. However, after the procedure, the patient angrily notices that he can no longer oppose his thumb. The patient, realizing that our opposable thumbs are what help to separate us from lower animals, sues your colleague for $1,000,000.
a.What branch of what nerve was accidentally damaged when the aspiration needle was inserted, and why is it particularly susceptible to this type of damage?
b.What muscles does this branch innervate?
c.The nerve that gives off this branch also is responsible for the innervation of two other intrinsic muscles of the hand and one extrinsic thumb muscle. Name them.
d.What nerve innervates the remaining 13 intrinsic muscles of the hand? Name these muscles.
e.In addition to the two aforementioned nerves, there is one other nerve that innervates muscles that move the thumb. Name it, and name the muscles
2.A seven year old boy is brought screaming into the E.R. because he has just stepped on a nail that has pierced deep into the sole of his foot. You, the medical student rotating through the E.R., intelligently comment that the puncture is so deep it must have passed through all four muscular layers of the foot. The resident on call (another graduate from the medical school across town) takes you aside and asks you to remind him about the four layers and what muscles and tendons they contain. Nostalgically, you recall your glory days chumming with Drs. Adinolfi and Clemente.
a. You break it down as follows:
b.As you pull the nail out, it looks like there might be damage to the medial plantar nerve. What nerve is this a branch of, and what muscles will be affected?
4.Match the following symptoms with their corresponding nerves
e.Carpal tunnel syndrome 1. Radial nerve
f.Winged scapula 2. Thoracodorsal nerve
g.Claw hand 3. Common fibular nerve
h.Wrist Drop 4. Median nerve
i.Foot Drop 5. Long thoracic nerve
6.Tibial nerve
7. Ulnar nerve
5. The arching blood flow of the hand is elegant and beautiful. What are the arches and what arteries are their major and minor contributors?
6.At dinner, you overhear your cousin complaining about having lost sensation on parts of his index middle and ring fingers and on the palmar aspect of his thumb. He also complains that he can no longer extend his index and middle fingers or oppose his thumb. You know that he is a workaholic computer hacker, so the diagnostic lightbulb flashes on inside your head and you tell him that he has Carpal Tunnel Syndrome.
a. What nerve is involved in this problem?
b.How is this condition treated surgically?
c.What are the other structures that pass through the Carpal Tunnel?
d.Name the carpal bones?
STRUCTURE LIST
sole of foot
plantar blood vessels
medial and lateral plantar nerves
plantar aponeurosis
abductor hallucis
abductor digiti mini
flexor digitorum brevis
quadratus plantae
lumbricals
flexor hallucis brevis
flexor digiti minimi
tendons of flexor digitorum and hallucis longus
plantar and dorsal interossei
deep plantar arterial arch
extensor region of forearm
abductor pollicis longus
extensor pollicis brevis
extensor pollicis longus
radial artery
extensor carpi radialis longus and brevis
extensor carpi ulnaris
extensor digitorum
supinator
posterior interosseous nerve
brachioradialis
extensor indicis
dorsal interossei muscles
extensor digiti minimi
palm of hand
palmar aponeurosis
palmaris brevis
abductor and flexor pollicis brevis
opponens pollicis
abductor and flexor digiti minimi brevis
opponens digiti minimi'
ulnar artery and superficial palmar arch
ulnar and median nerves
flexor retinaculum
recurrent branch of median nerve
flexor digitorum superficialis and profundus tendons
flexor pollicis longus tendon
lumbricals
palmar and dorsal interossei
adductor pollicis
deep palmar arch and radial artery