Week 7 Flashcards
1
Q
What are the bones in the proximal row of the hand in order of most lateral to most medial?
A
- Scaphoid
- Lunate
- Triquetrum
- Pisiform
2
Q
What are the bones in the distal row of the hand in order of most lateral to most medial?
A
- Trapezium
- Trapezoid
- Capitate
- Hamate
3
Q
What kind of joints are the intercarpal joints?
A
Synovial joints
4
Q
Metacarpals extend from the ___ to the ___
A
Metacarpals extend from the carpal bones to the digits
5
Q
In what order are the metacarpals numbered?
A
Numbered one to five from lateral to medial
6
Q
What are the components of a metacarpals?
A
- Head
- Body (shaft)
- Base
7
Q
What are the components of a phalange?
A
- Head
- Body
- Base
8
Q
What finger has only 2 phalanges?
A
The thumb ( proximal and distal)
9
Q
What is the biggest wrist bone?
A
Capitate
10
Q
What bones sit on the other on the proximal row of bones of the wrist?
A
The pisiform sits on the triquetrum
11
Q
On what side of the hand do we see the hook of the hamate and the pisiform?
A
On the palmar surface of the hand
12
Q
Another word for palmar is ___
A
Another word for palmar is volar
13
Q
What does it mean to be a synovial joint?
A
Have these things:
- Articular cartilage lining the joint surfaces
- A fibrous joint capsule
- Synovial membrane lining the joint capsule
- Synovial fluid between the joint
14
Q
On what surface of the hand do we have the thickening of fascia?
A
Thickening of fascia about
wrist on both anterior and
posterior sides
15
Q
What side of the hand has the extensor retinaculum?
A
Posterior side (back of the hand)
16
Q
What does the extensor retinaculum do?
A
Prevents bowing of long extensor tendons
17
Q
On what side is the flexor retinaculum?
A
The anterior side
18
Q
What does the flexor retinaculum do?
A
Converts the carpals into a concave surface forming the carpal tunnel
19
Q
What does the carpal tunnel do?
A
Allows passage of the
flexor tendons and median nerve into the palm of the hand
20
Q
What is the medial attachment of the flexor retinaculum?
A
The pisiform and hook of
hamate
21
Q
What is the lateral attachment of the flexor retinaculum?
A
The trapezium (distal) and scaphoid (proximal)
22
Q
How many compartments of the extensor retinaculum are there?
A
6
23
Q
What is in the 1st compartment of the extensor retinaculum counting from the radial end?
A
- Abductor pollicis longus
- Extensor pollicis brevis
24
Q
What causes de quervains tendonitis?
A
The inflammation of the tendons of abductor pollicis longus and extensor pollicis brevis, which is why they are called the de quervains muscle
25
What is in the 2nd compartment of the extensor retinaculum counting from the radial end?
- Extensor carpi radialis brevis and longus
26
What is in the 3rd compartment of the extensor retinaculum counting from the radial end?
- Extensor pollicis longus
27
What helps separates the compartments of the extensor retinaculum?
A bony prominence on the radius, called the dorsal tubercle of the radius/ listers tubercle
28
What is in the 4th compartment of the extensor retinaculum counting from the radial end?
- All 4 tendons of extensor digitorum communis
| - Extensor indicis
29
What is in the 5th compartment of the extensor retinaculum counting from the radial end?
- Extensor digiti minimi
30
What is in the 6th compartment of the extensor retinaculum counting from the radial end?
Extensor carpi ulnaris
31
What is the biggest compartment of the extensor retinaculum counting from the radial side?
4th
32
The structures that do not go through the carpal tunnel goes through the _____
The structures that do not go through the carpal tunnel goes through the *canal of guyon*
33
What passes through the canal of guyon?
- Ulnar artery
| - Ulnar nerve (closer to the pisiform)
34
____ forms the superficial part of the palmar arch
*Ulnar artery* forms the superficial part of the palmar arch
35
What does the ulnar artery connect with to form the superficial part of the palmar arch
Radial artery
36
What are the bones that form the bony part of the carpal tunnel?
- Pisiform
- Triquetrum
- Lunate
- Scaphoid
- Trapezium
37
There is a separate compartment in the carpal tunnel for the ___
There is a separate compartment in the carpal tunnel for the *flexor carpal radialis*
38
What are the contents of the carpal tunnel?
- Tendons of flexor digitorum profundus
- Flexor pollicis longus
- Flexor carpi radialis
- Median nerve
- Tendons of flexor digitorum superficialis
39
Which of the contents of the carpal tunnel sits the most deep?
Tendons of flexor digitorum profundus
40
What is the function of the palmar aponeurosis?
Serves to protect soft tissues of the palm and maintain position of the flexor tendons
41
Where does the palmar aponeurosis come from?
Flexor retinaculum
42
Where does the palmar aponeurosis extend to?
The heads of the metacarpals
43
What happens to the palmar aponeurosis upon getting to the head of the metacarpals?
It divides into 4 longitudinal bands adhering to the fibrous tissue of the proximal phalanges
44
What is the most superficial and lateral of the thenar muscles?
Abductor pollicis brevis
45
What are the thenar muscle?
- Abductor pollicis brevis
- Flexor pollicis brevis
- Oppones pollicis
46
Where do the tendons of flexor digitorum superficialis (FDS) and profundus (FDP) enter a common synovial sheath?
Deep to the flexor retinaculum and palmar aponeurosis
47
The tendons of flexor digitorum superficialis (FDS) and profundus (FDP) enter ___ and a synovial membrane covers the tendons within the tunnel
The tendons of flexor digitorum superficialis (FDS) and profundus (FDP) enter *osseofibrous digital tunnels8* and a synovial membrane covers the tendons within the tunnel
48
The osseofibrous digital tunnels are composed of?
Composed of fibrous connective tissue
49
What does the osseofibrous digital tunnels serve to do?
Serve to hold the tendons onto the phalanges
50
Digits 1 and 5 have synovial sheaths that are continuous with the synovial sheaths of the ___
Digits 1 and 5 have synovial sheaths that are continuous with the synovial sheaths of the *palm*
51
What happens to the synovial sheath of digits 2, 3 and 4?
They terminate about the
| middle of the palm and are not continuous with the synovial sheaths of the palm
52
True or False
The synovial sheath of digits 2-4 are separate the do not communicate with each other
True
53
The only nerve in the carpal tunnel is the ___
The only nerve in the carpal tunnel is the *median nerve*
54
What are the superficial tendons in the carpal tunnel?
Tendons of the flexor digitorum superficialis
55
What are the deep tendons in the carpal tunnel?
Flexor digitorum profundus
56
What tendons will be seen when you cut a finger off?
- Flexor digitorum superficialis
| - Flexor digitorum profundus
57
What vessels are in the finger, listed in order?
- Palmar digital nerve
- Palmar digital artery
- Palmar digital vein
58
What is the origin of abductor pollicis brevis?
Scaphoid and trapezium
59
What is the insertion of abductor pollicis brevis?
Lateral side of base of proximal phalanx
60
What is the innervation of abductor pollicis brevis?
Recurrent branch of median n.
61
What is the action of abductor pollicis brevis?
Abducts thumb at CMC joint
62
What is the origin of flexor pollicis brevis?
Flexor retinaculum and trapezium
63
What is the insertion of flexor pollicis brevis?
Lateral side of base of proximal phalanx
64
What is the innervation of flexor pollicis brevis?
Recurrent branch of median n.
65
What is the action of flexor pollicis brevis?
Flex thumb
66
What is the origin of opponens pollicis?
Flexor retinaculum and trapezium
67
What is the insertion of opponens pollicis?
Lateral side of first metacarpal
68
What is the innervation of opponens pollicis?
Recurrent branch of median n.
69
What is the action of opponens pollicis?
Oppose thumb
70
What are the hypothenar muscles?
- Abductor digiti minimi
- Flexor digiti minimi brevis
- Opponens digiti minimi
71
What is the origin of abductor digiti minimi?
Pisiform
72
What is the insertion of abductor digiti minimi?
Base of proximal phalanx of 5th digit
73
What is the innervation of abductor digiti minimi?
Ulnar n.
74
What is the action of abductor digiti minimi?
Abduction
75
What is the origin of flexor digiti minimi brevis?
Hamate
76
What is the insertion of flexor digiti minimi brevis?
Base of proximal phalanx of 5th digit
77
What is the innervation of flexor digiti minimi brevis?
Ulnar n.
78
What is the action of flexor digiti minimi brevis?
Flexes 5th digit
79
What is the origin of opponens digiti minimi?
Hamate
80
What is the insertion of opponens digiti minimi?
Medial border of 5th metacarpal
81
What is the innervation of opponens digiti minimi?
Ulnar n.
82
What is the action of opponens digiti minimi?
Oppose the 5th digit
83
What is the origin of the oblique head of adductor pollicis?
Carpal bones and bases of metacarpals 2 and 3
84
What is the insertion of the oblique head of adductor pollicis?
Base of proximal phalanx of thumb
85
What is the innervation of the oblique head of adductor pollicis?
Ulnar n.
86
What is the action of the oblique head of adductor pollicis?
Adduct thumb
87
What is the origin of the transverse head of adductor pollicis?
Shaft of the 3rd metacarpal
88
What is the insertion of the transverse head of adductor pollicis?
Base of proximal phalanx of thumb
89
What is the innervation of the transverse head of adductor pollicis?
Ulnar n.
90
What is the action of the transverse head of adductor pollicis?
Adduct thumb
91
What is the origin of the lumbricals?
Tendons of the FDP
92
What is the insertion of the lumbricals?
Lateral side of the extensor expansions
93
What is the innervation of lumbrical 1 and 2 of the lumbricals?
Lumbricals 1 and 2 – median n.
94
What is the innervation of lumbrical 3 and 4 of the lumbricals?
Lumbricals 3 and 4 – ulnar n.
95
What is the action of the lumbricals?
Flex the MP joints and extend the proximal IP joints
96
How many palmar interossei are there?
3
97
What is the origin of the palmar interossei?
Sides of metacarpal bones
98
What is the insertion of the palmar interossei?
Base of proximal phalanges and extensor expansion
99
What is the innervation of the palmar interossei?
Ulnar n.
100
What is the action of the palmar interossei?
Adduct fingers
101
How many dorsal interossei are there?
4
102
What is the origin of the dorsal interossei?
Arise via two heads from adjacent sides of metacarpals
| between which they lie
103
What is the insertion of the dorsal interossei?
Proximal phalanges and extensor expansion
104
What is the innervation of the dorsal interossei?
Ulnar n.
105
What is the action of the dorsal interossei?
Abduct fingers at MP joints
106
The median nerve enters the hand through the ___
The median nerve enters the hand through the *carpal tunnel*
107
What does the median nerve supply motor input to in the hand?
The three thenar muscles and lumbricals 1 and 2
108
What does the median nerve supply sensory input to in the hand?
From the anterior surface of the digits 1, 2 and 3 and
| the lateral half of digit 4 as well as the lateral surface of the palm of the hand
109
How does the ulnar nerve enter the hand?
The palm on the medial side of the wrist through the canal of Guyon
110
What does the ulnar nerve supply motor input to in the hand?
The hypothenar muscles, adductor pollicis (2 heads),
| lumbricals 3 and 4, and the palmar and dorsal interossei muscles
111
What does the ulnar nerve supply sensory input to in the hand?
From the medial aspect of the palm, medial aspect of the dorsum of the hand, digit 5 and half of digit 4
112
How does the radial nerve enter the hand?
Enters hand through anatomical snuffbox
113
What does the radial nerve supply motor input to in the hand?
NOTHING
114
What does the radial nerve supply sensory input to in the hand?
From the lateral two thirds of the dorsum of the hand via the superficial radial branch
115
The radial artery runs __ to 1st digit, through the anatomical snuffbox and enters the palm between the heads of the first ____
The radial artery runs *posterior* to 1st digit, through the anatomical snuffbox and enters the palm between the heads of the first *dorsal interosseous muscles*
116
What artery supplies the 1st digit and what gives rise to it?
- Princeps pollicis artery
| - Radial artery gives rise to it
117
What artery supplies the 2nd digit and what gives rise to it?
- Radialis indicis artery
| - Radial artery gives rise to it
118
What does the radial artery do after giving rise to other arteries?
Forms the deep palmar arch
119
Where does the superficial radial brand of the radial artery rise from?
Arises from radial artery before the radial artery enters the anatomical snuffbox
120
The superficial radial branch pf the radial artery runs ___ and joins with the ___
The superficial radial branch pf the radial artery runs *superficial* and joins with the *superficial palmar arch*
121
How does the ulnar artery enter the hand?
Enters palm through canal of Guyon
122
The ulnar artery divides into a __ and ___ which forms the superficial and deep palmar arches
The ulnar artery divides into a *deep palmar branch and a superficial palmar branch*
which form the superficial and deep palmar arches
123
What are the digital arteries?
Three digital arteries that arise from the superficial and deep palmar arch
124
Out of the abductor pollicis brevis and flexor pollicis brevis, which is more medially placed?
Flexor pollicis brevis
125
The cutaneous branches of the ulnar nerve innervates the __?
5th finger and half of the 4th finger
126
There are 2 palmar interossei muscles on the ____ and 1 one the ____
There are 2 palmar interossei muscles on the *lateral side of digits 4 and 5* and 1 one the *medial side of digit 2*
127
Describe where the dorsal interossei muscles are from
- Lateral side of the 5th metacarpal
- Lateral and medial side of the 2nd, 3rd, and 4th
- Medial side of the 1st
128
Why is the 1st dorsal interossei (between the thumb and index finger) important?
It has a little gap between the heads for the passage way of the radial artery to become the deep palmar arch
129
On the palmar side what does the ulnar nerve provide sensory innervation to?
The hypothenar eminence and the 5th and half of the 4th finger
130
What are the muscles in the hypothenar eminence?
The abductor digiti minimi, the flexor digiti minimi brevis, and the opponens digiti minimi
131
On the palmar side what does the median nerve provide sensory innervation to?
Thumb, index finger, middle finger, and half of the ring finger. The remain portion of the pal not innervated by the ulnar nerve
132
On the palmar side what does the radial nerve provide sensory innervation to?
The little surface of the thenar eminence on the radial side of the hand
133
What is the shoulder complex?
Set of 4 articulations involving sternum, clavicle, ribs, scapula and humerus
134
What type of joint is the sternoclavicular joint?
Saddle type synovial joint (functions as ball-and-socket)
135
What does the articular disc of the sternoclavicular joint do?
Connects the medial end of clavicle to the 1st costal cartilage and sternum
136
There are thickenings of the fibrous capsule that form the __ and ___ ligaments
There are thickenings of the fibrous capsule that form the *anterior and posterior
sternoclavicular* ligaments
137
Where does the costoclavicular ligament come from?
1st rib and its costal cartilage
138
Where does the costoclavicular ligament come go?
The anterior margin of the medial end of the clavicle
139
What is the blood supply of the sternoclavicular joint?
Internal thoracic and suprascapular arteries
140
What is the nerve supply of the sternoclavicular joint?
Branches of suprascapular n. and n. to subclavius
141
What does the costoclavicular ligament do?
Helps minimize the excessive movement of the clavicle
142
How many degrees of freedom of movement does the clavicle have?
3 deg
143
What movement does the clavicle?
- Elevation and depression
- Protraction and retraction
- Posterior rotation (moves the least)
144
What is the frequency of a sternoclavicular joint injury?
Fractures and dislocations are unusual (<5% of shoulder girdle injuries)
145
In what population is a sternoclavicular injury most common?
More common in children and adolescents
146
What is the mechanism of a sternoclavicular joint injury?
High-energy mechanisms (falls from height, motor vehicle collisions, sports-related injuries)
147
What part and in what direction is the sternoclavicular joint most displaced?
Most cases – medial end of clavicle displaced anteriorly (Posterior displacement less common)
148
What kind of joint is the acromioclavicular joint?
Plane synovial joint
149
Where is the acromioclavicular joint?
Junction of lateral end of clavicle to the acromion process of scapula
150
The capsule of the acromioclavicular joint is strengthened by ____
The capsule of the acromioclavicular joint is strengthened by *the acromioclavicular ligament*
151
What does the coracoclavicular ligament do?
Strengthens lateral end of the clavicle by attaching to clavicle
152
What are the two parts of the coracoclavicular ligament?
Trapezoid and Conoid
153
What is the blood supply of the acromioclavicular ligament?
Suprascapular and thoracoacromial arteries
154
What is the nerve supply of the acromioclavicular ligament?
Lateral pectoral and axillary nerves
155
The sternoclavicular and acromioclavicular joints allow ___
The sternoclavicular and acromioclavicular joints allow *the scapula to move*
156
What happens with anterior tilting of the scapula?
The inferior part of the scapula pokes out and the acromion dips. (vice versa for posterior tilting)
157
What does a type 1 AC joint injury entail?
An injury to the AC joint ligament, with no real disruption to the joint
158
What does a type 2 AC joint injury entail?
A full tear of the AC ligament, and the coracoarocmial ligaments are still fine
159
What does a type 3 AC joint injury entail?
There is a rupture of both the AC joint ligament and the coracoacromial joint ligament
160
What does a type 4 AC joint injury entail?
The clavicle is pushed posteriorly relative to the acromion
161
What does a type 5 AC joint injury entail?
The clavicle is pushed posteriorly relative to the acromion and there is a disruption to the sternal ligaments
162
What does a type 6 AC joint injury entail?
The clavicle goes underneath the acromion, and behind the tendons of biceps and coracobrachialis
163
What forms the scapulothoracic joint?
The convex surface of the posterior thoracic cage with the concave surface of the anterior scapula
164
What lines the anterior surface of the scapula
Subscapularis and serratus anterior
165
What are the movements that the scapulothoracic joint can achieve?
- Elevation and depression
- Protraction and retraction
- Upward and downward rotation
166
What is scapular dyskinesia?
Alteration in the normal position or motion of the scapula during coupled scapulohumeral movements
167
What do clinicians do to identify scapular dyskinesia?
Clinicians observe scapular motion and congruence during self directed upper extremity movements
168
What is a type 1 scapula?
Inferior angle prominence of the scapula (anteriorly tilted)
169
What is a type 2 scapula?
Medial border prominence of the scapula. (protracted)
170
What is a type 3 scapula?
Superior border prominence of the scapula (posteriorly tilted)
171
What is a type 4 scapula?
Symmetrical (Normal)
172
What kind of joint is the glenohumeral joint?
Ball and socket – synovial joint
173
What makes up the glenohumeral joint?
Head of humerus joins with glenoid fossa
174
Both surfaces of the the glenohumeral joint is covered by ____
Both surfaces of the the glenohumeral joint is covered by *hyaline cartilage*
175
___ deepens the socket of the glenoid fossa for a better fit
*Glenoid labrum* deepens the socket of the glenoid fossa for a better fit
176
The superior portion of the glenoid labrum blends with the ____
The superior portion of the glenoid labrum blends with the *tendon of long head of biceps brachii*
177
___ allows for the massive movement of the glenohumeral joint
*Axillary pouch* allows for the massive movement of the glenohumeral joint
178
The loss of the ___ is prevalent in adhesive capsulitis
The loss of the *axillary pouch* is prevalent in adhesive capsulitis
179
What is a SLAP tear?
Superior Labrum Anterior to Posterior tear
180
What could cause a SLAP tear?
* Motor vehicle accident
* Fall on outstretched arm
* Forceful pull on arm
* Rapid or forceful movement of arm
* Shoulder dislocation
181
What is a type 1 SLAP tear?
Where there is slight separation of the labrum superiorly to anterior to posterior, but the tendon is still intact on the supraglenoid tubercle
182
What is a type 2 SLAP tear?
There is more deterioration on the superior part of the labrum
183
What is a type 3 SLAP tear?
The labrum gets pulled off and the tendon separates from the labrum
184
What is a type 4 SLAP tear?
When the tendon pulls away completely along with the labrum and falls into the joint capsule
185
A SLAP tear is as a result of what?
Wearing down the labrum that occurs slowly over time
186
The glenohumeral joint has a fibrous capsule that is ___ and allows for ____
The glenohumeral joint has a fibrous capsule that is *thin and loose* and allows for *wide ROM*
187
The capsule of the glenohumeral joint is lined by ____
The capsule of the glenohumeral joint is lined by *synovial membrane*
188
What are the intrinsic ligaments of the glenohumeral joint?
- Glenohumeral ligaments
- Transverse humeral ligament
- Coracohumeral ligament
189
The glenohumeral joint has 3 fibrous bands found only on the ____
The glenohumeral joint has 3 fibrous bands found only on the *internal aspect of the capsule*
190
The glenohumeral ligament radiate laterally from the ___ into three band: __, ___ and ___
The glenohumeral ligament radiate laterally from the *supraglenoid tubercle into three bands: Superior,
middle and inferior bands*
191
What is the function of the glenohumeral ligaments?
They function to strengthen the anterior capsule of the joint
192
The transverse humeral ligament attaches from the ___ to ___, converting the groove into a ___
The transverse humeral ligament attaches from the *greater to lesser tubercle converting the groove into a canal*
193
The glenohumeral ligaments are found anterior to the ____
The glenohumeral ligaments are found anterior to the *coracohumeral ligament*
194
___ forms a sling that holds the head of the humerus in the glenoid fossa
*The inferior glenoihumeral ligament* forms a sling that holds the head of the humerus in the glenoid fossa
195
The bursa between the rotator cuff muscles and the acromion is called the ___
The bursa between the rotator cuff muscles and the acromion is called the *subacromial bursa*
196
The coracoacromial arch is between the __ and the ___
The coracoacromial arch is between the *acromion and the coracoacromia ligament*
197
What is the rotator interval?
The portion of the shoulder joint where the rotator interval capsule is reinforced externally by the coracohumeral ligament and internally by the superior glenohumeral ligament
198
Most of the time when the shoulder dislocates, its through the ____
Most of the time when the shoulder dislocates, its through the *rotator interval*
199
What is the main job of the transverse humeral ligament?
Maintains the position of the
long head of the biceps tendon in the bicipital groove
and the synovial sheath
200
The coracohumeral ligament extends from the ___ to the ____
The coracohumeral ligament extends from the * base of the coracoid to the anatomical neck of the humerus.*
201
What is the function of the coracohumeral ligament?
It functions to strengthening of the superior part of the capsule
202
What are the extrinsic ligaments of the glenohumeral joint?
Coracoacromial Ligament
203
The coracoacromial ligament spans from the ___ to the ___
The coracoacromial ligament spans from the coracoid process to the acromion process*
204
What does the coracoacromial ligament do?
It helps form the coracoacromial arch which protects the humerus from superior displacement.
205
What forms the coracoacromial arch?
The acromion, coracoid and the coracoacromial ligament
206
Where are the bursae around the glenohumeral joint located?
Bursae are located where tendons interact with bone, ligament or another tendon
207
What are the bursae of the glenohumeral joint?
- Subscapular bursa
- Subtendinous bursa
- Subacromial bursa
208
Where is the subscapular bursa located?
Located between subscapularis tendon and the neck of the scapula
209
The subscapular bursa is an extension of the ___
The subscapular bursa is an extension of the *synovial capsule*
210
The subtendinous bursa is also an extension of the synovial capsule under the ___ for protection of the ___
The subtendinous bursa is also an extension of the synovial capsule under the *transverse humeral ligament for protection of the long head of the biceps brachii tendon*
211
Where is the subacromial bursa?
Between the acromion and the supraspinatus tendon
212
The subacromial bursa also extends between the __ and ___ to form the ___
The subacromial bursa also extends between the *deltoid and the proximal end of the humerus to form the subdeltoid bursa*
213
What is the blood supply of the glenohumeral joint?
Anterior and posterior circumflex arteries and branches from the suprascapular artery
214
What is the nerve supply of the glenohumeral ligament?
Suprascapular, lateral pectoral, and axillary nerves supply the
Glenohumeral joint.
215
What ligaments that stop the shoulder from falling down with the arm at the side/ the passive restraint that keeps the head of the humerus attached to the glenoid fossa?
The superior, middle and inferior glenohumeral ligament and the coracohumeral ligament
216
What happens to the ligaments of the glenohumeral joint with ADD?
There is a shortening of the joint capsule, lengthening of he coracohumeral ligament
217
What happens to the ligaments of the glenohumeral joint with ABD?
The coracohumeral ligament shortens and the thickenings of the joint capsule lengthens
218
What has to happen for the shoulder to be fully elevated?
An ER has to occur in order to get full elevation
219
At what degree of arm elevation is the glenohumeral painful arc?
45-60 deg all the way to 120 deg
220
At what degree of arm elevation is the acromioclavicular painful arc?
170 deg to 180 deg
221
What causes the glenohumeral painful arc pain?
The humerus is in close proximity to the acromion, so subacromial impingement can occur
222
What is the scapulohumeral rhythm?
Natural kinematic rhythm or timing exists between GH abduction and scapulothoracic (ST) upward rotation
223
After about 30° of ___, the scapulohumeral rhythm is remarkably constant and
at a 2:1 ratio, meaning that for every 3° of shoulder abduction, 2° comes from ___ and 1° comes from ___
After about 30° of *abduction,* the scapulohumeral rhythm is remarkably constant and
at a 2:1 ratio meaning that for every 3° of shoulder abduction, *2° comes from GH joint abduction and 1° comes from ST upward rotation*
224
The 60° of ST upward rotation result from simultaneous ___ and ___
The 60° of ST upward rotation result from *simultaneous elevation of the clavicle at the sternoclavicular (SC) joint combined with upward rotation of the scapula at the AC joint*
225
The clavicle retracts at SC joint during full ___ (about 15°)
The clavicle retracts at SC joint during full *scapulohumeral (SH) abduction* (about 15°)
226
Scapula posteriorly tilts at about __° and externally rotates at about __°
Scapula posteriorly tilts at about *20° and externally rotates at about 10°*
227
The clavicle rotates posteriorly around its ___ axis
The clavicle rotates posteriorly around its *long axis*
228
The humerus naturally externally rotates during ___
The humerus naturally externally rotates during *SH abduction*
229
Movement of the upper extremity requires the involvement of what joints?
- GH joint
- AC joint
- SC joint
230
60 deg of upper extremity motion comes between the __ and ___
60 deg of upper extremity motion comes between the *scapular and thorax*
231
What is reverse scapulohumeral rhythm?
The scapula does all the movement, with no involvement of the GH joint
232
In normal movement of the upper extremity, what is the order of movement of the joints?
The GH joint moves 1st, the ST joint adds in and full ER of the GH to get the rotation
233
Glenohumeral joint sacrifices __ for ___
Glenohumeral joint sacrifices *stability for mobility*
234
Glenoid labrum provides ‘suction cup’ effect to maintain ___
Glenoid labrum provides ‘suction cup’ effect to maintain *joint integrity*
