Arm Flashcards
Repeated excessive pressure and friction causes bursa to become inflamed. This is called/
Subcutaneous olecranon bursitis “students elbow”
Biceps Brachii
O: Short head- tip of coracoid process. Long head- supraglenoid tubercle and glenoid labrum.
I: Tuberosity of the radius and fascia of the forearm via bicipital aponeurosis.
A: Supination of forearm; when supine, it flexes forearm; slight flexion at shoulder joint.
N: Musculocutaneous n. (C5, C6, C7)
B: Brachial a.
What’s the most effective at producing elbow flexion?
Flexed elbow (cloe to 90 degrees) and supinated forearm.
Brachialis
O: distal 1/2 of anterior surface of humerus
I: coronoid process and tuberosity of ulna
A: flexion of forearm in all positions
N: Musculocutaneous n. (C5,C6), radial n. (C5,C7)
B: Brachial a.
Coracobrachialis
O: tip of coracoid process I: Middle 1/3 of medal surface of humerus A: flexion and ADD of arm N: Musculocutaneous n. (C5,C6,C7) B: Axillary and brachial aa.
What occurs with “popeye deformity”?
Detached long head of biceps brachii m. from supraglenoid tubercle balls up near center of distal anterior aspect of arm.
Triceps Brachii
O: Long head- infraglenoid tubercle. Lateral head- Posterior surface of humerus superior to radial groove. Medial head- posterior surface of humerus inferior to radial groove.
I: proximal end of olecranon and fascia of forearm
A: Main extensor of forearm, long head aids in ADD and extension of humerus
N: Radial n. (C6, C7, C8)
B: profunda brachii a.
Anconeus
O: Lateral epicondyle of humerus
I: Lateral surface of olecranon and superior part of posterior surface of ulna
A: assists with forearm extension; tenses capsule of elbow joint
N: Radial n. (C7, C8, T1)
What is the brachial a. continuous with and what does it terminate into?
Continuation of axillary a. at inferior border of trees major.
-terminates in cubital fossa as radial and ulnar aa.
What accompanies the radial n. in radial groove and what does it terminate into?
profunda brachii a. terminating into middle and radial collateral aa.
What does the superior ulnar collateral a. anatomose with?
Anastomoses with posterior ulnar recurrent a. and inferior ulnar collateral a.
What does the inferior ulnar collateral a. anastamose with?
Anastomoses with superior ulnar collateral a. and anterior ulnar recurrent a.
What are the superficial v. of the arm?
- Cephalic v.
- Basilic v.
- Median cubital v.
- Intermediate antebrachial v. (20%)
What are the deep v. of the arm?
Brachial vv. (venae comitantes)
What does the cephalic v. communicate with?
What does it pass by?
Where does it enter?
- communicates at elbow with median cubital v.
- passes lateral to biceps brachii m.
- enters deltopectoral groove
What does the basilica v. pierce?
Where does it run?
What does it merge with?
- pierces brachial fascia near inferior and middle 1/3 of arm
- runs superiorly with brachial a. and medial ante brachial cutaneous n.
- Merges with brachial vv. to form axillary v.
What does the median cubital v. cross and what does it join?
- crosses cubital fossa obliquely
- joins cephalic and basilica vv.
Where does the intermediate ante brachial v. (20%) run and what does it divide into?
- runs up meddling of anterior forearm
- divides into: median basilic v. (joins with basilic v.), median cephalic v. (joins with cephalic v.)
What does the brachial vv. accompany?
Where is it formed?
Where does it end?
-Accompanies with brachial a.
Formed at elbow by the union of the venae comitantes of ulnar and radial aa.
-end by merging with basilica v. to form axillary v.
What are the 5 nerves that innervate the arm?
- musculocutaneous n.
- radial n.
- medial brachial cutaneous n.
- intercostobrachial n.
- superior lateral brachial cutaneous n.
Musculoctaneous n.
- Where does it come from?
- What does it pierce and supply?
- Where and what does it emerge into?
- From lateral cord
- pierces coracobrachialis, supplies it, also supplies biceps brachii, brachialis mm.
- emerges into the lateral antebrachial cutaneous n.
- cutaneous= of relating to, affecting the skin
Radial n.
- Where does it branch from?
- What does it run with?
- What does it supply?
- What are it’s branches?
- What does it divide into?
- from terminal branch of posterior cord of brachial plexus
- runs with profunda brachii a. in radial groove
- supplies all muscles in posterior compartment
- it’s branches are infer lateral brachial cutaneous n., posterior brachial cutaneous n., posterior ante brachial cutaneous n.
- divides into: deep branch of radial n. and superficial branch of radial n.
Medial brachial cutaneous n.
- where is it from?
- what does it supply
- from medial cord of brachial plexus
- supplies skin of medial arm to medial epicondyle
Intercostobrachial n.
- where is it from?
- what does it join?
- what does it supply?
- from 2nd inercostal n.
- joins with medal brachial cutaneous n.
- supplies skin of upper medial arm
Superior lateral brachial cutaneous n.
- where is it from?
- what does it supply?
- from axillary n.
- supplies skin over lower deltoid
What are the causes of Injury to radial n. (C5-C8) in arm?
- improper use of crutches
- falling asleep with arm over chair (“saturday night palsy”)
- posterior dislocation of glenohumeral (rare)
What occurs with wrist drop?
- due to inability to extend wrist and fingers at MP joint
- wrist assumes partly flexed position due to unopposed action of flexors and gravity
- loss of sensation to inferior lateral arm, posterior arm, forearm, dorsum of hand and lateral fingers
- loss of sensation to dorsum of hand and lateral fingers
What are the contents of the cubital fossa?
- terminal part of brachial a.
- deep accompanying vv.
- biceps brachii t.
- median n.
- radial n.
What are the boundaries of the cubital fossa?
- lateral: brachioradialis m.
- medial: pronator teres m.
- base (superior): line between medial and lateral epicondyles
- floor: supinator and brachialis mm.
- roof: skin, fascia and bicipital aponeurosis
What does the annular l. encircle?
-encircles radial head
Where is the oblique cord?
-what does it do?
- from coronoid process to radial shaft
- limits rotation and also limits distal movement of radius (pulling)
What does the interosseous membrane do?
-limits proximal displacement of radius (pushing)
What type of joint is the radio-ulnar joint?
fibrocartilaginous
What muscles are in the superficial layer of the forearm flexor compartment?
- pronator teres m.
- flexor carpi radialis m.
- palmaris longus m.
- flexor carpi ulnaris m.
What muscles are in the deep layer of the forearm flexor compartment?
- flexor digitorum profundus m.
- flexor pollicis longus m.
- pronator quadratus m.
Pronator Teres
O: ulnar head - coronoid process. Humeral head - medal epicondyle (ME) via common flexor tendon
I: Middle of convexity of lateral surface of radius
A: Pronation (when more speed and power is needed) and flexion of forearm
N: median n. (C6, C7)
Flexor Carpi Radialis (FCR)
O: ME via common flexor tendon
I: base of 2nd metacarpal
A: Flexion and radial deviation of the hand
N: median n. (C6, C7)
*flexion is produced when acting with FCU
-radial deviation is produced when actin with ECRL and ECRB
Palmaris Longus
O: ME via common flexor tendon
I: distal 1/2 of flexor retinaculum and apex of palmar aponeurosis
A: flexion of hand at wrist and tenses palmar aponeurosis
N: median n. (C7, C8)
Flexor Carpi Ulnaris (FCU)
O: humeral head - ME via common flexor tendon. ulnar head - olecranon and posterior border via aponeurosis
I: pisiform, hook of hamate and 5th metacarpal
A: flexion and ulnar deviation of hand
N: ulnar n. (C7, C8)
Flexor Digitorum Superficialis (FDS)
O: humeroulnar head - ME via common flexor tendon and coronoid process. radial head - superior 1/2 anterior border
I: Shafts of middle phalanges of medial 4 digits via split tendon
A: flexion of PIPs; strong flexion of MPs; flexion of wrist
N: Median (C7, C8, T1)
