Exam #1 - Muscle & Supporting Structures Flashcards
1
Q
Only muscles can adapt to both immediate (acute) & repeated long- term (chronic) external forces that can destabilizes the body
- It is coupled to both the external environment & the internal control mechanisms of the nervous system
A
Skeletal muscle
2
Q
Non-contractile elements of muscle
A
Connective tissue “harness” of muscle
3
Q
The innermost layer that seperate individual muscle fibers & myofibrils
A
Endomysium
4
Q
Encases fiber bundles
A
Perimysium
5
Q
Enveloping fascial sheath around the entire muscle
A
Epimysium
6
Q
The connective tissue framework is the ____ source of muscle’s resistance to ____ elongation
A
The connective tissue framework is the primary source of muscle’s resistance to passive elongation
7
Q
What influences a muscles ultimate function?
A
Muscle shape
8
Q
What muscle fibers run parallel to one another & to the central tendon
A
Fusiform muscle
9
Q
What muscle fibers approach their central tendon obliquely
A
Pennate muscles
10
Q
- Refers to the angle of orientation between the muscle fibers & tendon
- Produce greater maximal force than fusiform muscles of similar volume
A
Pennation Angle
11
Q
a muscle produces a pulling force while maintaining a
constant length
A
Isometric
12
Q
a muscle produces a pulling force as it shortens (contracts)
A
Concentric
13
Q
muscle produces a pulling force as it is being elongated by another more dominant force
A
Eccentric
14
Q
muscle or muscle group most directly involved in the initiation & execution of movement
A
Agonist
15
Q
a muscle that opposes the action of another
A
Antagonist
16
Q
muscles that work together to create a movement
A
Synergist
17
Q
2 or more muscles on opposing sides of a joint work together to provide joint stability or create movement
A
Force-Couple
18
Q
The distance a muscle can shorten after it has been elongated to its maximum
A
Functional Excursion
19
Q
In some cases, the functional excursion, or range of a muscle, is ____ influenced by the joint or joints it ____
A
In some cases, the functional excursion, or range of a muscle, is **directly **influenced by the joint or joints it crosses
20
Q
- A point in the range of motion where a muscle is shortened at each joint it crosses where it can no longer shorten
- This leads to decreased force production
A
Active Insufficiency
21
Q
- A point in the range of motion where a muscle is lengthened at each joint it crosses where it can no longer lengthen
- Leads to decreased joint range of motion & decreased force production
A
Passive Insufficiency
22
Q
Sternoclavicular Joint Stabalizer Tissues (5)
A
- Ant. SCJ ligament
- Post. SCJ ligament
- Interclavicular ligament
- Costoclavicular ligament
- Articular disc
23
Q
Sternoclavicular joint stabalizer muscles (4)
A
- Sternocleidomastoid
- Sternothyroid
- Sternohyoid
- Subclavius muscles
24
Q
Acromioclavicular joint stabalizer tissues (4)
A
- Superior ACJ capsular ligament
- Inferior ACJ capsular ligament
- Coracoclavicular ligament
- Articular disc (if present)
25
Acromioclavicular joint stabalizer muscles (2)
1. Deltoid
2. Upper trapezius
26
Glenohumeral joint stabalizer tissues (4)
1. Joint capsule
2. Glenohumeral ligament
3. Coracohumeral ligament
4. Glenoid labrum (increases depth also)
27
Glenohumeral joint stabalizer muscles (5)
1. Rotator cuff muscles (subscapularis, supraspinatus, infraspinatus, & teres minor)
2. Long head of the biceps brachii
28
What primary motion draws the **superior glenohumeral ligament** taut
adduction
29
What primary motion draws the **middle glenohumeral ligament** taut
abduction & external rotation
30
What primary motion draws the **inferior glenohumeral ligament (axillary pouch)** taut
90° ABD + anterior-posterior translation
31
What primary motion draws the **inferior glenohumeral ligament (anterior band)** taut
90° ABD + full ER
32
What primary motion draws the **inferior glenohumeral ligament (posterior band)** taut
90° ABD + full IR
33
What primary motion draws the **coracohumeral ligament** taut
ADD + ER
34
The **fibrocartilage at articular surface of glenoid labrum** is for ____ loading
The fibrocartilage at articular surface of glenoid labrum is for **compressive** loading
35
The **outer rim of glenoid labrum** is for ____ loading
The outer rim of glenoid labrum is for **tensile** loading
36
Coracoacromial arch is formed by
1. Coracoacromial ligament
2. Acromion process
37
Contents of the Subacromial Space
1. Supraspinatus muscle & tendon
2. Subacromial bursa
3. Long head of the biceps
4. Part of the superior capsule
38
What are the 4 causes of decreased subacromial space
1. Hypertrophy
2. Protraction
3. Diabolo effect
4. Architectural change
39
Origin & Insertion of proximal stabalizers of the shoulder
**Origin:** spine, ribs & cranium
**Insertion:** scapula & clavicle
40
Origin & Insertion for distal mobilizers of the shoulder
**Origin:** scapula & clavicle
**Insertion:** humerus or ulna
41
**Elevator** mm acting on scapulothoracic junction (3)
1. Upper trapezius
2. Levator scapulae
3. Rhomboids
42
**Upward rotator** mm acting on scapulothoracic junction (2)
1. Serratus anterior
2. Upper & lower trapezius
43
**Downward rotator** mm acting on scapulothoracic junction (2)
1. Rhomboids
2. Pectoralis minor
44
**Depressor** mm acting on scapulothoracic junction (4)
1. Lower trapezius
2. Latissimus dorsi
3. Pectoralis minor
4. Subclavius
45
**Retractor** mm acting on scapulothoracic junction (3)
1. Middle trapezius
2. Rhomboids
3. Lower trapezius
46
**Protractor** mm acting on scapulothoracic junction (1)
Serratus anterior
47
2 joints & 7mm that **elevate arm**
**Glenohumeral joint:** anterior/middle deltoid, supraspinatus, coracobrachialis, biceps (long head)
**Scapulothoracic joint:** serratus anterior, trapezius
48
5 primary mm that **extend & adduct arm**
1. Posterior deltoid
2. Latissimus dorsi
3. Teres minor
4. Triceps brachii (long head)
5. Pectoralis major (sternocostal head)
49
Primary mm that **internally** & **externally rotate arm**
**Internal rotators:** subscapularis, ant deltoid, pectoralis major, latissiumus dorsi, teres major
**External rotators:** infraspinatus, teres minor, post deltoid
50
Function of infraspinatus, teres minor & subscapularis during elevation
exert a depression force on the humeral head
51
Function of infraspinatus & teres minor during elevation
externall rotate the humerus
52
Rotator cuff muscles (4)
1. Supraspinatus
2. Infraspinatus
3. Teres minor
4. Subscapularis
53
Function of supraspinatus during elevation
* Compresses humeral head against glenoid
* Restricts excessive superior humeral translation
54
Strengthens the articular capsule providing stability of the elbow joint
Collateral ligaments
55
Motions that increase tension of **medial collateral ligament (anterior fibers)**
1. valgus
2. extension & flexion
56
Primary valgus stabalizer of elbow
Medial collateral ligament (anterior fibers)
57
Primary varus stabalizer of elbow
Lateral (ulnar) collateral ligament
58
External rotation of elbow A.K.A
supination
59
Motions that increase tension of **medial collateral ligament (posterior fibers)**
1. valgus
2. flexion
60
Motions that increase tension of **radial collateral ligament**
1. varus
2. external rotation (supination)
61
Motions that increase tension of **lateral (ulnar) collateral ligament**
1. Varus
2. External rotation & flexion
62
Motions that increase tension of **annular ligament**
1. distraction of radius
2. external rotation (supination)
63
The tight fit between the trochlea & the trochlear notch provides most of the ____ of the elbow
The tight fit between the trochlea & the trochlear notch provides most of the **stability** of the elbow
64
* Binds the radius to the ulna
* Attachment for extrinsic hand mm
* Transmits forces proximally
Function of interosseous membrane
65
When weight is transmitted across interosseous membrane via central band to the ulna it promotes...
a sharing of the load to the elbow
66
Load at the radiocarpal joint during compression ____% of load crosses on the radial side & ____% crosses on the ulnar side
Load at the radiocarpal joint during compression **80%** of load crosses on the radial side & **20%** crosses on the ulnar side
67
The radius is held to the ulna via a ____ ring
The radius is helf to the unla via a **fibro-osseous** ring
68
Stability of the DRUJ is achieved via muscle ____ & local ____ ____
Stability of the DRUJ is achieved via muscle **activation** & local **connective tissues**
69
DRUJ tissue stabalizers (2)
1. Triangular fibrocartliage complex (TFCC)
2. Distal fibers of interosseous membrane
70
Capsular ligaments of the DRUJ (2)
1. Capsular ligaments of DRUJ
2. Ulnar collateral ligament
71
DRUJ muscle stabalizers (2)
1. pronator quadratus
2. tendon of externsor carpi ulnaris
72
2 mm & 1 structure that **limits supination**
1. pronator teres
2. pronator quadratus
3. TFCC
73
2 mm & 1 structure that **limits pronation**
1. Biceps
2. Supinator mm
3. TFCC
74
**Flexor** mm of **Elbow** (4)
1. Biceps brachii
2. Brachialis
3. Brachioradialis
4. Pronator teres
75
**Extensor** mm of **Elbow** (2)
1. Triceps brachii
2. Anconeous
76
Primary & secondary **pronator** mm of **elbow** (5)
**Primary pronators:** pronator teres, pronator quadratus
**Secondary pronators:** flexor carpi radialis, palmaris longus, brachioradialis
77
**Triangular Fibrocartilage Complex**
* The ____ stabalizer of DRUJ
* ____ ulnar side of wrist
* Forms part of the ____ of radiocarpal joint
* Helps ____ part of compression forces that naturally cross wirst/hand into forearm (~20%)
* The **primary** stabalizer of DRUJ
* **Reinforces** ulnar side of wrist
* Forms part of the **concavity** of radiocarpal joint
* Helps **transfer** part of compression forces that naturally cross wirst/hand into forearm (~20%)
78
Extrinsic ligaments of wrist (4)
1. Dorsal radiocarpal
2. Radial collateral
3. Palmar radiocarpal
4. TFCC
79
Connects carpal bones & forearm (stiff, not as elastic)
Extrinsic ligaments
80
Capable of greater elongation before permanent deformation (interconnect carpal bones)
Intrinsic ligaments
81
Intrinsic ligaments of wrist (3)
1. Short (distal row)
2. Intermediate lig
3. Long ("inverted V")
82
Long ("inverted V") ligaments (2)
1. Palmar intercarpal
2. Dorsal intercarpal
83
Carpometacarpal Joint ligaments help to
* ____ the extent & direction of joint motion
* ____ joint alignment
* ____ ____ produced by activated muscle
* **Control** the extent & direction of joint motion
* **Maintain** joint alignment
* **Dissipate forces** produced by activated muscle
84
What position is the **anterior oblique ligament** the most taut
Full extension (hitch hiker position)
85
What position is the **ulnar collateral ligament** the most taut
ABD + Ext
86
What position is the **first intermetacarpal ligament** the most taut
Flexion
87
What position is the **posterior oblique ligament** the most taut
Flexion
88
What position is the **radial collateral ligament** the most taut
All movements to varying degrees except extension
89
**Primary wrist extensor** mm act on the wrist ONLY (3)
1. ECR longus
2. ECR brevis
3. ECU
90
**Secondary wrist extensor** mm act of wrist & hand (4)
1. Extensor digitorum
2. Extensor indicis
3. Extensor digiti minimi
4. Extensor pollicis longus
91
**Primary wrist flexor** mm act on wrist only (3)
1. FCR
2. FCU
3. Palmaris longus
92
**Secondary wrist flexor** mm act on wrist & hand (5)
1. Flexor digitorum profundus
2. Flexor digitorum superficialis
3. Flexor pollicis longus
4. Abductor pollicis longus
5. Extensor pollicis brevis
93
Main function of wrist extensors is to ____ & ____ wrist during active flexion of fingers (making a fist)
Main function of wrist extensors is to **position** & **stabalize** wrist during active flexion of fingers
94
When making a fist this position optimizes ____-____ relationship of ____ finger flexors = **maximal grip strength**
When making a fist this position optimizes **length-tension** relationship of **extrinsic** finger flexors **= maximal grip strength**
95
7 mm responsible for Radial Deviation
1. ECR longus
2. ECR brevis
3. Extensor pollicis longus
4. Extensor pollicis brevis
5. FCR
6. Abductor pollicis longus
7. Flexor pollicis
96
5 mm responsible for Ulnar Deviation
1. ECU
2. FCU
3. Flexor digitorum profundus
4. Flexor digitorum superficialis
5. Extensor digitorum
