Chapter 7 Flashcards
Anterior chest and shoulder:
Pectoralis major/minor
Serratus anterior
Deltoid
Anterior brachium:
Biceps brachii
Brachialis
Brachioradialis
Anterior antebrachium:
Pronator teres
Palmaris longus
Supinator
Anterior antebrachium:
Flexor carpi radialis Flexor carpi ulnaris Flexor digitorum superficialis Flexor digitorum profundus Flexor pollicis longus
Nerves:
Median
Ulnar
Posterior brachium:
Triceps brachii Extensor carpi radialis Extensor carpi radialis brevis Extensor digitorum Extensor carpi ulnaris Extensor pollicis longus
Muscles of arm/forearm:
Anconeus Coracobrachialis Pronator quadratus Abductor pollicis longus Extensor pollicis brevis Extensor indicis
Nerves:
Musculocutaneous
Radial
Axillary
Biceps brachii:
Long and short heads
Triceps brachii:
Long, lateral, and medial heads
“M” branches of the brachial plexus
musculocutaneous nerve
median nerve
ulnar nerve
musculocutaneous nerve
innervates the flexor muscles of the brachium and pierces the coracobrachialis muscle
intermuscular septum
divides the anterior compartment from the posterior compartment
border of the triangle
“cubital fossa”
- “imaginary line” between the medial and lateral epicondyles
- brachioradialis muscle
- pronator teres muscle
structures in the cubital fossa
tendon of the biceps brachii, brachial artery (branching into the radial and ulnar arteries), and median nerve
deep to the cubital fossa
supinator
superficial muscles of the anterior forearm
sequential order: flexor carpi radialis, palmaris longus (if present), flexor carpi ulnaris
snuffbox
proximal to distal are: abductor pollicis longus, extensor pollicis brevis, and extensor pollicis longus.
The abductor pollicis longus tendon extends to
the metacarpal
The extensor pollicis brevis tendon extends to
the proximal phalanx
The extensor policis longus tendon extends to
the distal phalanx
coracobrachialis
only muscle that does not cross the elbow joint, but instead crosses the shoulder joint—thus, it assists in arm movement
muscles of the anterior compartment that assist in flexion of the antebrachium are innervated by
the musculocutaneous nerve
muscles of the posterior
compartment are innervated by
the radial nerve
coracobrachialis muscle is innervated by
the musculocutaneous nerve
brachioradialis muscle innervated by
the radial nerve, because the origin point stems the posterior side
triceps brachii
Radial nerve
Anconeus
Synergist to triceps
Radial nerve
Coracobrachialis*
Flexes and adducts humerus
Musculocutaneous nerve
Biceps brachii
Musculocutaneous nerve
Brachialis
(lifts ulna)
Musculocutaneous nerve
Brachioradialis
Radial nerve
The anterior side, or flexor side, of the antebrachium is innervated primarily by
the median nerve
carpal tunnel syndrome
affects the median nerve
flexor digitorum profundus is innervated by 2 nerves
ulnar and median
Pronator teres
Median nerve
Flexor carpi radialis
Median nerve
Palmaris longus
Tenses skin and fascia of hand during hand movements
Median nerve
Flexor carpi ulnaris
Ulnar nerve
Flexor digitorum
superficialis
Median nerve
Flexor pollicis longus
Branch of median
Flexor digitorum profundus
Medial half by ulnar; lateral half by median
Pronator quadratus
PM of forearm pronation
Median nerve
venipuncture
median cubital fossa vein, triangular region anterior to the elbow joint
Other contents within the cubital fossa
biceps tendon, bifurcation of the brachial artery, and the median nerve
The posterior side, or extensor side, of the brachium is primarily innervated by
the radial nerve
Brachioradialis
Synergist in flexing forearm
Radial nerve
Extensor carpi radialis longus
Radial nerve
Extensor carpi radialis brevis
Radial nerve
Extensor digitorum
PM of finger extension
Radial nerve
Extensor carpi ulnaris
Radial nerve
Supinator
Assists biceps brachii to forcibly supinate forearm
Radial nerve
Abductor pollicis longus
Radial nerve
Extensor pollicis brevis and longus
Radial nerve
Extensor indicis
Extends index finger
Radial nerve
radial fossa
or anatomical snuffbox, is a triangular-shaped region just proximal to the thumb
tendons that border the snuffbox:
extensor pollicis longus (EPL) which forms the
medial border
abductor pollicis longus (APL)
extensor pollicis brevis (EPB) which form the lateral border, and the styloid process of the radius which forms the proximal border
triangular region are 3 important structures
the radial artery, a branch of the radial nerve, and the cephalic vein
brachial plexus
5 major nerves of the upper limb come
from a plexus of nerves
brachial plexus originates from
from the spinal cord roots C5-C8 and T1. The roots C5 and C6 form the superior trunk, root C7 forms the middle trunk, and roots C8 and T1 form the inferior trunk.
median nerve is pinched or compressed within the carpal tunnel of the wrist
Carpal tunnel syndrome
Symptoms include:
carpel tunnel syndrome
This can be seen in cases involving pregnancy or diabetes, where swelling is common, or even stem from repetitious movement (e.g. a baker kneading dough, piano player, etc.) that causes tendons and/or tendinous sheaths to swell.
numbness, weakness, pain, and/or tingling of the hand
9 tendons and 1 nerve that run through the wrist
- 4 tendons of the flexor digitorum superficialis
- 4 tendons of the flexor digitorum profundus
- 1 tendon of the flexor pollicis longus
- the median nerve
If medications and/or physical therapy cannot remedy the situation
surgery can be carried out to cut the flexor retinaculum (also called transverse carpal ligament) in order to “widen” the carpal tunnel and free its contents
Hirayama disease
neurological syndrome that usually affects men and causes severe muscular atrophy and weakness of the forearms and hands
corresponding nerves affected by Hirayama
brachial plexus stems from cervical spinal roots (and T1), thus when the cervical spinal cord
atrophies
Erb’s palsy
associated with upper brachial plexus injury, where the nerves stemming from C5 and C6 are damaged
extended upper brachial plexus injury
Root C7 injured
two major nerves that come from these roots are (Erb’s palsy)
the musculocutaneous and axillary nerves
if two major nerves are injured (the musculocutaneous and axillary nerves)
when damaged the patient will be unable to abduct the shoulder, laterally rotate the shoulder, supinate the forearm, and/or flex the upper limb
“waiter’s tip”
minimized mobility, the upper limb hangs limply, due to damaged nerves
Klumpke palsy occurs
when the lower brachial plexus is injured affecting the nerves stemming from C8 and T1
symptoms of “claw hands” are exhibited
because nerves primarily innervate the hand muscles in Klumpke palsy
Cases of Klumpke palsy are usually seen in difficult births
where the baby’s shoulder gets caught in the birth canal, causing a severe stretch between the neck and the shoulder resulting in hyper-abduction of the arm
which nerves are affected in Klumpke
median and ulnar nerves
If a patient cannot extend the 4th and 5th fingers, he/she most likely has injured
ulnar nerve
