Lab 13 Thoracic Limb Learning Issues

Question 1

should joint stability

Answer 1

no collateral ligaments on shoulder joint; the tendons of subscapularis and infraspinatus take their place; stability also provided via medial and lateral stablizers

Question 2

medial shoulder stablizers

Answer 2

subscapularis

Question 3

lateral shoulder stabilizers

Answer 3

supraspinatus, infraspinatus, and teres minor (not main lateral stabilizer)

Question 4

cephalic vein

Answer 4

located in lateral pectoral groove between brachiocephalicus and pectorals descendent; runs along cr aspect of the limb dorsally (brachium) then to a medial position between elbow and carpus (antebrachium)

Question 5

collateral ulnar artery

Answer 5

arises from cd surface of brachial artery about 5cm distal to deep brachial

Question 6

transverse cubital artery

Answer 6

arises from cranial surface opposite cubital lymph nodes and disappears under biceps

Question 7

subscapular artery

Answer 7

arises from axillary and passes proximally between subscapularis and teres major

Question 8

pectoral muscles

Answer 8

originate from the sternum
superficial pectorals
deep pectorals
subclavius

Question 9

subclavius

Answer 9

insertion on sternum; loose insertion on scapular fascia and the proximal part of supraspinatus

Question 10

deep pectorals

Answer 10

attaches to sternum and has medial and lateral insertions on humerus

• md insertion is cr pt of lesser tubercle
• lateral insertion becomes aponeurotic as it crosses over inter tubercular groove to attach to cr pt of greater tubercle

Question 11

superficial pectorals attachment and innervation

Answer 11

origin- first 2 sternebrea usually part of 3rd
insertion- whole crest of greater tubercle of the humerus
innervation- ventral branches spinal nerves C7/C8

Question 12

superficial pectorals action

Answer 12

adduct limb when it is not bearing weight or prevent the limb from being abducted when bearing weight

Question 13

deep pectoral muscles attachment and innervation

Answer 13

origin- ventral part of sternum and fibrous raphe between fellow muscles, deep abdominal fascia in region of xiphoid cartilage
insertion- major portion partly musclar, partly tendinous on lesser tubercle of humerus, an aponeurosis to greater tubercle and its crest, cd part to medial brachial fascia
innervation- cd pectoral nerves (C8, T1)

Question 14

deep pectoral muscles fx

Answer 14

when limb is advanced and fixed in supporting position: pull trunk crly and extend shoulder jt; when limb not supporting weight draw limb cdly and flex shoulder jt, adduct limb

Question 15

extrinsic limb muscles

Answer 15

rhomboideus, serratus ventralis, latissimus dorsi, brachiocephalicus, trapezius, omotransversarius

Question 16

rhomboideus

Answer 16

attachments-Nuchal and dorsoscapular ligaments, C2-T8 to scapular cartilage
innervation- lateral branches of dorsal branches of cervical spinal nerves= motor

Question 17

serratus ventralis

Answer 17

attachments- transverse processes of certical vertebrea (C4-C7) and first 8-9 ribs to dorsomedial scapula
innervation- lateral branches of dorsal branches of cervical spinal nerves= motor

Question 18

latissimus dorsi

Answer 18

attachments- thoracolumbar fascia to teres major tuberosity (md humerus)
innervation- lateral branches of dorsal branches of cervical spinal nerves= motor

Question 19

brachiocephalicus attachments and innervation

Answer 19

attachments: crest of humerus to mastoid process of skull
innervation: ventral branch of Accessory Nerve

Question 20

trapezius attachments and innervation

Answer 20

attachments: funicular portion of nuchal ligament to scapular spine
Innervation: dorsal branch of accessory nerve

Question 21

omotransversarius attachments and innervation

Answer 21

attachments- shoulder fascia to transverse processes of cervical vertebrea (C2-C4)
innervation:dorsal branch of accessory nerve

Question 22

tendon of origin of biceps brachii

Answer 22

passes from supraglenoid tubercle through inter tubercle groove, tendon is partly cartilaginous and closely molded to intermediate tubercle in groove; intertubercular bursa lies between tendon of insertion of biceps brachii and the inter tubercle groove; )
- tendon contributes to passive stay apparatus

Question 23

intertubercle bursa and shoulder jt

Answer 23

the bursa does not communicate with shoulder joint (most of the time) so if medicating joint and bursa need to do two separate injections

Question 24

how does tendon of biceps brachii contribute to passive stay apparatus?

Answer 24

avoids shoulder flexion

Question 25

how does venous blood drain in thoracic forelimb

Answer 25

via cephalic or subclavian vein

Question 26

path of arterial blood flow through collateral ulnar artery

Answer 26

1. axillary
2. brachial
3. collateral ulnar artery
4. Medial and lateral palmar metacarpal