A&P 1.10 Flashcards
Muscle Terminology
Define muscle belly
fleshy portion of muscle that’s responsible for muscle contraction
Muscle Terminology
Define muscle tendon
dense collagen fibers which attach muscle to bone
Muscle Terminology
Define aponeurosis
broad, dense sheet of CT that connects - ms-ms
- ms-bone
- ms-skin
Muscle Terminology
Define origin
- proximal or superior attachment
- attaches on a less movable bone
Muscle Terminology
Define insertion
- distal or inferior attachment
- attaches on a more movable bone
Muscle Fasciculi
List the 4 ways fasciculi are arranged
- Parallel
- Pennate
- Convergent
- Circular
Muscle Fasciculi
Describe parallel arrangement
Fascicles lay parallel to one another (same fiber direction)
Muscle Fasciculi
Describe pennate arrangement
- feathering arragenemtn of fascicles
- can be either uni (half feather) or bipennate (full feather)
Muscle Fasciculi
Describe convergent fascicle arrangement
fibers have multiple origins that converge at one insertion point
Ex: glutes, deltoids
Muscle Fasciculi
Describe circular fascicle arrangement
circle shaped fibers
Ex: orbit, mouth, sphincters
Naming Skeletal Muscles
List the different methods of naming muscles
- Relative size
- Location
- Shape
- Muscle fiber direction
- Number of origins
- Location of ms attachment points
- Action
Naming Skeletal Muscles
Examples of naming by relative size
Gluteus
- Maximus
- Medius
- Minimus
Naming Skeletal Muscles
Examples naming skeletal muscles by location
Tibialis anterior vs posterior
Naming Skeletal Muscles
Examples of skeletal muscles named based on shape
- deltoid
- rhomboids
Naming Skeletal Muscles
Examples of muscles named by fiber direction
Rectus femoris
Naming Skeletal Muscles
Examples of muscles named by number of origins
- Triceps
- Biceps
Naming Skeletal Muscles
Examples of naming skeletal muscles by location of the muscle attachment points
Sternocleidomastoid
Naming Skeletal Muscles
Examples of naming skeletal muscles by action
- Extensors
- Flexors
Rotator Cuff Muscles
Name the 4 rotator cuff muscles
- Supraspinatus
- Infraspinatus
- Teres minor
- Subscapularis
Rotator Cuff Muscles - Location, Origin, Insertion, Action
Supraspinatus
L: Posterior shoulder deep
O: Supraspinous fossa of scapula
I: Greater tubercle of humerus (superior facet)
A: ABducts arm at shoulder
Rotator Cuff Muscles - Location, Origin, Insertion, Action
Infraspinatus
L: Posterior shoulder superficial
O: Infraspinous fossa of scapula
I: Greater tubercle of humers (intermediate facet)
A: Laterally rotates arm at shoulder
Rotator Cuff Muscles - Location, Origin, Insertion, Action
Teres Minor
L: Posterior axilla superficial
O: Superior 1/2 of lateral border of scapula
I: Greater tubercle of humerus (Inferior facet)
A: Laterally rotates arm at shoulder
Rotator Cuff Muscles - Location, Origin, Insertion (Action)
Subscapularis
L: Anterior scapula deep
O: Subscapular fossa of scapula
I: Lesser tubercle of humerus
A: Medially rotates arm at shoulder
Scapula & Posterior Arm Muscles
List the muscles
- Teres major
- Triceps brachii
Scapula & Posterior Arm Muscles - L, O, I, A
Teres major
L: Posterior axilla superficial
O: Inferior angle (lateral side) and lower 1/2 lateral border of scapula
I: Bicipital groove of humerus (medial lip)
A: “_____” of arm at shoulder
- Extension
- ADduction
- Medial rotation
Scapula & Posterior Arm Muscles - L, O, I, A
Triceps brachii
L: Posterior arm superficial
O:
- Long head: infraglenoid tubercle of scapula
- Lateral head: posterior, proximal half of humerus
- Medial head: posterior, distal half of humerus
I: olecranon process of ulna
A: extends forearm at elbow (long head also extends arm at shoulder)
Anterior Arm Muscles
List the muscles
- Brachialis
- Biceps brachii
Anterior Arm Muscles - L, O ,I ,A
Brachialis
L: Anterior arm deep
O: Distal 1/2 of anterior surface of humerus
I: Proximal ulna
A: Flexion of forearm at elbow
Anterior Arm Muscles - L, O, I, A
Biceps brachii
L: Anterior arm superficial
O: - Short head: coracoid process of scapula
- Long head: supraglenoid tubercle of scapula
I: Radial tuberosity and proximal ulna (by way of biciptal aponeurosis)
A: “________” forearm at elbow
- flexion
- supination
(short head also flexes arm at shoulder)
Lateral Arm Muscles - L, O, I, A
Deltoid
L: Lateral shoulder superficial
O: - Anterior: Lateral 1/3 of clavicle
- Middle: Acromion
- Posterior: Spine of scapula
- I: Deltoid tuberosity of humerus
- A: - Anterior: Flexion, medial rotation
- Mid: ABduction
- Posterior: Extension & lateral rotation of arm at shoulder
Deep Posterior/Lateral Forearm Muscles - L, O, I, A
Supinator
L: Posterior, lateral forearm deep
O: Lateral epicondyle of humerus & posterior border of ulna
I: Proximal 1/3 of radius
A: Supination of forearm at elbow
Superficial Posterior Forearm Muscles - L, O, I, A
Extensor Carpi Radialis Brevis
L: Posterior forearm superficial
O: Kateral epicondyle of humerus
I: Base of 3rd metacarpal
A: Extension & radial deviation of hand at wrist
Superficial Posterior Forearm Muscles - L, O, I, A
Extensor Carpi Radialis Longus
L: Posterior forearm superficial
O: Lateral supracondylar ridge of humerus
I: Base of 2nd metacarpal
A: Extensoin & radial deviation of hand at wrist
Deep Posterior Forearm Muscles - L, O, I, A
Extensor Indicis
L: Posterior forearm deep
O: Ulna & interosseous membrane
I: Base of intermediate phalanx of index finger
A: Extension of index finger
Deep Posterior Forearm Muscles - L, O, I, A
Extensor Pollicis Brevis
L: Posterior forearm deep
O: Radius & interosseous membrane
I: Base of proximal phalanx of thumb
A: Extension of thumb
Part of anatomical snuff box
Deep Posterior Forearm Muscles - L, O, I, A
Extensor Pollicis Longus
L: Posterior forearm deep
O: Middle 1/3 of ulna & interosseous membrane
I: Base of distal phalanx of thumb
A: Extension of thumb
Part of anatomical snuff box
Deep Posterior Forearm Muscles - L, O, I, A
Abductor Pollicis Longus
L: Posterior forearm deep
O: Ulna, radius & interosseous membrane
I: Base of 1st metacarpal
A: Abduction & extension of thumb
Part of anatomical snuff box
Superficial Posterior Forearm Muscles - L, O, I, A
Extensor Digitorum
L: Posterior forearm superficial
O: Lateral epicondyle of humerus
I: Distal phalanges of medial 4 digits
A: Extension of phalanges
Superficial Posterior Forearm Muscles - L, O, I, A
Extensor Carpi Ulnaris
L: Posterior forearm superficial
O: Lateral epicondyle of humerus
I: Base of 5th metacarpal
A: Extension & ulnar deviation of hand at wrist
Superficial Posterior Forearm Muscles - L, O, I, A
Extensor Retinaculum (not a muscle)
L: CT band around posterior wrist
O: Attaches at distal radius & ulna
I: n/a
A: Keeps extensor tendons from bowing out
Superficial Posterior Forearm Muscles - L, O, I, A
Anconeus
L: Posterior forearm superficial
O: Lateral epicondyle of humerus
I: Olecranon process & lateral edge of ulna shaft
A: Extends elbow (ABducts ulna during supination)