Forelimb muscle의 Origin, Insertion, Action을 공부해 보자.
Epaxial
Nuchal ligament

| Nuchal ligament | |
|---|---|
| O | 첫 3 Thoracic spinous process |
| I | C2의 dorsal spinous process |
| A | 머리 지지, 과도한 ventroflexion을 막음 |
Intrinsic muscles
Lateral scapula & shoulder
Supraspinatus (가시위근)![]() ![]() ![]() | |
|---|---|
| O | Supraspinous fossa (가시위오목) |
| I | Greater tubercle, anterior to the infraspinatus |
| A | 어깨관절의 extend & stabilize (주요 폄근) |
Infraspinatus (가시아래근)![]() ![]() | |
|---|---|
| O | Infaspinous fossa (가시아래오목) |
| I | Lateral greater tubercle (between the Supraspinatus and Teres minor tendons) |
| A | 어깨관절의 extend & flex - Abduct shoulder - Rotate arm laterally - Stabilize the joint |
Teres minor (작은원근)![]() ![]() | |
|---|---|
| O | Distal 1/3 of caudal border of scapula |
| I | Greater tubercle, caudal to infraspinatus tendon |
| A | Flex shoulder, externally rotate arm |
| Deltoideus (어깨세모근) (큰 쪽) Scapular part / (작은 쪽) Acromial part ![]() ![]() | |
|---|---|
| O | (1) Spine of scapula (어깨뼈가시) - Spinous Head (2) Acromion (봉우리) - Acromial head |
| I | (both) Deltoid tuberosity of humerus (상완뼈 세모근거친면) |
| A | flex shoulder |
Medial scapular & shoulder
Teres major (큰원근)![]() ![]() ![]() ![]() | |
|---|---|
| O | Caudal angle & border of scapular (어깨뼈 뒤각, 뒤모서리) |
| I | Teres major tuberosity of Humerus (상완뼈 큰원근거친면) |
| A | Flex shoulder (어깨관절의 주요 굽힘근), Rotate arm medially |
Subscapularis (어깨밑근)![]() ![]() | |
|---|---|
| O | Subscapular fossa of scapula (어깨뼈밑오목) |
| I | minor tubercle of the humerus (상완뼈 작은결절) |
| A | - Adduct & extend shoulder - during flexion : aids in stabilizing joint - Tendon functions as a medial collateral ligament |
Caudal arm
Anconeus (앞다리굽이근)![]() | |
|---|---|
| O | distal-lateral humerus (just proximal to elbow) |
| I | Lateral surface of proximal 1/8 of ulna |
| A | Extend elbow |
| N | Radial n. |
Triceps brachii (상완세갈래근)![]() | - L, A, Md, Lt 순 | |||
|---|---|---|---|---|
| Medial head (Humeral heads) | Lateral head | Accessory head | Long head (Scapular head) | |
| O | Medial surface of humerus | Proximal lateral humerus | Neck of humerus (상완뼈목) | Caudal border of scapula (어깨뼈뒤모서리) |
| I | (all) Olecranon (자뼈꿈치머리) | |||
| A | (all) Extend elbow | + flex shoulder | ||
| N | (all) Radial n. |
Cranial arm
Biceps brachii (상완두갈래근)![]() ![]() | |
|---|---|
| O | supraglenoid tubercle of scapula (어깨뼈 오목위결절) |
| I | Ulna & Radius (medially, just distal to elbow) (노,자뼈 거친면) |
| A | Flex elbow (앞다리굽이관절의 주요 굽힘근), extend shoulder |
Cranio-lateral forearm
Extensor Carpi Radialis (노쪽앞발목폄근)![]() ![]() | |
|---|---|
| O | Lateral epicondyle of humerus |
| I | Bases (proximal ends) of metacarpals of 2 and 3 |
| A | Extend carpus |
| N | Radial n. |
Common digital extensor![]() | |
|---|---|
| O | Lateral epicondyle of humerus |
| I | Extensor processes of the distal phalanges of digits 2-5 |
| A | Extend joints of the four digits and carpus |
| N | Radial n. |
Caudo-medial forearm
Deep digital flexor (깊은발가락굽힘근)![]() | ![]() | ||
|---|---|---|---|
| Humeral head | Ulnar head | Radial head | |
| O | Medial epicondyle of humerus | Proximal 3/4 of caudal border of ulna | Middle 1/3 of medial border of radius |
| I | (all) Palmar surface of base(proximal end) of distal phalanx of each digit | ||
| A | (all) Flex digits & carpus |
Flexor carpi ulnaris![]() ![]() | ||
|---|---|---|
| Ulnar head | Humeral head | |
| O | Caudal border of medial surface of olecranon | Medial epicondyle of humerus |
| I | (all) Accessory Carpal bone | |
| A | (all) Flex carpus |
Superficial digital flexor![]() ![]() | |
|---|---|
| O | Medial epicondyle of humerus |
| I | Medial & lateral surfaces of the middle phalanges of digits 2-5 (wrapping aroudn the deep digital flexor tendon) |
| A | Flex carpus, metacarpophalangeal, proximal interphalangeal joints of digits 2-5 |



























