Wrist and Hand Flashcards
1
Q
Which is the longer of the wrist bones?
A
Ulna
2
Q
What is the structure of the head and neck of the radius?
A
The head is a thick disc with a concave superior surface for articulation with the convex capitulum. There is then a constricted neck which slopes medially and joins the shaft.
3
Q
What is the shape of the shaft of the radius?
A
The shaft is round proximally and triangular distally.
4
Q
Where does the interosseous membrane between radius and ulna go from and to?
A
It spans from just below the radial tuberosity to the medial side of the lower end of the radius.
5
Q
What are the surfaces of the distal radius?
A
- Medial
- Lateral
- Posterior
6
Q
What is found on the medial surface of the radius?
A
The concave ulnar notch, for articulation with the head of the ulna.
7
Q
What is found on the lateral surface of the radius?
A
A shallow groove for tendons of abductor pollicis longus and extensor pollicis brevis.
8
Q
Which structure is found on the posterior surface of the radius?
A
Dorsal tubercle
9
Q
What does the radius articulate with distally?
A
- Scaphoid
- Lunate
- Ulna via the ulnar notch
10
Q
What is the structure of the proximal ulna?
A
It is a large hook-shaped structure (olecranon process) for articulation with the trochlea of the humerus. The coronoid process then projects from the front of the shaft and has an upper articular surface which completes the trochlear notch.
11
Q
What are the bones of the first row of the carpus?
A
- Scaphoid
- Lunate
- Triquetral
- Pisiform
12
Q
How many bones are in the carpus?
A
8
13
Q
Which bones are in the distal row of the carpus?
A
- Trapezium
- Trapezoid
- Capitate
- Hamate
14
Q
Which carpal bones articulate with the radius and articular disc of the radioulnar joint?
A
- Scaphoid
- Lunate
- Triquetral
15
Q
What is the name of the joint between the two rows of carpal bones?
A
Midcarpal joint
16
Q
What is the name for the joints between carpal bones in the same row?
A
Intercarpal joints
17
Q
What are the joints called between the distal row of the carpus and the metacarpals?
A
Carpometacarpal joints
18
Q
What is the carpal tunnel formed from?
A
Ligaments hold the bones of the carpus in a compact mass with an anterior concavity (the carpal sulcus). The flexor retinaculum sits over the top of the carpal sulcus to form the carpal tunnel.
19
Q
Which part of the scapoid is palpable?
A
The anterior tubercle
20
Q
What are the articulations of the scaphoid?
A
- Proximally with the radius
- Distally with the head of capitate
- Medially with lunate
- Laterally with trapezium and trapezoid
21
Q
Why is the small non-articular area of scaphoid important?
A
It is the only region available for entry of blood vessels and it is a common fracture site.
22
Q
Which surface of lunate is larger: palmar or dorsal?
A
Palmar
23
Q
What are the articulations of lunate?
A
- Proximally with the radius and radiounlar articulating disc
- Distally with the head of capitate
- Medially with triquetral
- Laterally with scaphoid
24
Q
What are the articulations of triquetral?
A
- Proximally with the articulating disc of the radioulnar joint during ulnar deviation
- Distally with hamate
- Medially with lunate
- Laterally with pisiform via a deep concave surface
25
What type of bone is pisiform?
Small, round, sesamoid bone
26
Which tendon is pisiform embedded in?
Flexor carpi ulnaris
27
What are the medial and lateral borders of the carpal tunnel?
* Scaphoid tubercle (lateral border)
* Pisiform (medial border)
28
Which part of trapezium is palpable?
The tubercle and groove on its anterior surface are palpable.
29
What are the articulations of trapezium?
* Proximally with the scaphoid
* Distally with the base of the first metacarpal
* Medially with trapezoid
30
What type of joint is the joint between the trapezium and the base of the first metacarpal?
Synovial saddle joint
31
Why is the first carpometacarpal joint saddle while the others are not?
It allows for the thumbs to be opposable.
32
What are the articulations of trapezoid?
* Proximally with scaphoid
* Distally with the second metacarpal
* Medially with trapezium
* Laterally with capitate
33
Which is the largest carpal bone?
Capitate
34
What are the articulations of capitate?
* Proximally with scaphoid and lunate
* Distally with the third metacarpal (and slightly with the 2nd and 4th metacarpals)
* Medially with trapezoid
* Laterally with hamate
35
Why is the palmar surface of capitate roughened?
It serves as an attachment point for ligaments in the hand
36
What shape is hamate?
Wedge-shaped
37
What is the characteristic feature of hamate?
It has a large, curved, palpable hook projecting from its palmar surface
38
What are the articulations of hamate?
* Proximally with triquetral
* Distally with the fourth and fifth metacarpals
* Laterally with capitate
39
What are the attachments of the flexor retinaculum?
Pisiform and the hook of hamate medially and the scaphoid tubercle and both lips of the groove of trapezium laterally
40
What is the flexor retinaculum?
It is a strong band of connective tissue which maintains the positions of the long flexor tendons and converts the carpal sulcus into a tunnel.
41
Which tendon passes most laterally beneath the flexor retinaculum?
Flexor carpi radialis passes below the retinaculum in its own compartment with a synovial sheath.
42
Which tendon, beneath the flexor retinaculum, lies medially to the flexor carpi radialis tendon?
Flexor pollicis longus
43
Which tendons lie medially to flexor pollicis longus beneath the flexor retinaculum?
All 8 tendons of flexors digitorum superficialis and profundus
44
Which structure is separated into two sections either side of the flexor retinaculum?
The median nerve is separated into deep and cutaneous branches
45
What is the cause of carpal tunnel syndrome?
The tendon sheath of flexor digitorum superficialis tendons become inflamed and compress the deep branch of the median nerve which sits beneath them leading to abnormal activity of the median nerve
46
What are the attachments of the extensor retinaculum?
It attaches to the distal part of the anterior surface of the radius laterally and the distal end of the ulna, pisiform, triquetral and ulnar collateral ligament medially
47
How many tunnels are there in the extensor retinaculum?
6
48
What are the tendons in the synovial sheaths of the extensor retinaculum from lateral to medial?
1. Abductor pollicis longus and extensor pollicis brevis
2. Extensor carpi radialis longus and extensor carpi radialis brevi
3. Extensor pollicis longus
4. Extensor digitorum and extensor indicis
5. Extensor digiti minimi
6. Extensor carpi ulnaris
49
What is the name of the main joint at the wrist?
Radiocarpal joint
50
What does it mean that radiocarpal, midcarpal and intercarpal joints are interdependent?
It means that they are functionally independent so movements that affect one of these joints affect the others too
51
What type of joint is the radiocarpal joint?
A synovial ellipsoid joint
52
Which movements can occur at the radiocarpal joint?
* Flexion
* Extension
* Radial deviation
* Ulnar deviation
53
What are the articulating surface of the radiocarpal joint?
The radius and the articular disc form a continuous, concave, ellipsoid surface which receives the almost continous convex surface of the proximal row of carpal bones, bound together by interosseous ligaments.
54
What are the attachments of the radiocarpal joint capsule?
Distal edges of the radius and ulnar anteriorly and posteriorly and the radial and ulnar styloid processes laterally and medially.
Distally it attaches to the anterior and posterior margins of the articulating surfaces of the proximal row of carpal bones.
55
What are the attachments of the dorsal radiocarpal ligament?
* Posterior edge of the distal radius
* Posterior surface of scaphoid, lunate and triquetral
56
What are the attachments of the palmar radiocarpal ligament?
* Anterior edge of the distal radius and radial styloid process
* Anterior surface of proximal row of carpal bones
57
What are the attachments of the palmar ulnocarpal ligament?
* Anterior edge of the radioulnar articulating disc and the base of the ulnar styloid process
* Anterior surfaces of the proximal row of carpal bones
58
What are the attachments of the radial collateral carpal ligament?
* Tip of the radial styloid process
* Lateral side of the scaphoid process
59
What are the attachments of the ulnar collateral carpal ligament?
* Ulnar styloid process
* Base of pisiform and non-articular surfaces of triquetral
60
Which capsular ligaments in the radiocarpal joint become taut during flexion: anterior or posterior?
Posterior (anterior ligaments become taut during extension)
61
What type of joints are the intercarpal joints?
Plane synovial joints
62
Why are intercarpal joint movements very limited?
Interosseous ligaments between the carpal bones dramatically limit movement.
63
Why is there more movement in the intercarpal joints of the distal row than the proximal row?
The distal row has less extensive interosseous ligaments
64
What type of joints are the midcarpal joints?
Synovial plane joints
65
What are the articulations of the lateral part of the midcarpal joint?
* Scaphoid (convex)
* Trapezium and trapezoid (concave)
66
What are the articulations of the medial part of the midcarpal joint?
* Lunate and triquetral (concave)
* Capitate and hamate (convex)
67
What is the structure of the joint capsule of the midcarpal joint?
It is made of irregular bands of fibres running between the two rows of carpal bones. The palmar and dorsal intercarpal ligaments reinforce the capsule anteriorly and posteriorly. The collateral ligaments strengthen the joint capsule medially and laterally.
68
What is the normal ROM for wrist flexion?
80-90 degrees
69
What is the normal ROM for wrist extension?
70-90 degrees
70
What is the normal ROM for radial deviation?
15 degrees
71
What is the normal ROM for ulnar deviation?
30-45 degrees
72
Why is radial deviation so much less than ulnar deviation?
The radial styloid process extends more distally than the ulnar styloid process and blocks movement of the radius.
73
What is the structure of each metacarpal?
* Quadrilateral base
* Shaft
* Distal rounded head
74
What is different about the head of the first metacarpal compared to the other four?
It has two sesamoid bones embedded in short tendons crossing the joint which articulate with the palmar part of the joint surface.
75
Other than its saddle joint nature, why is the first metacarpal also more free to move separately than the others?
The second to fifth metacarpals have articular facets for engaging with one another.
76
How many phalanges are there in each hand?
14
77
Why is superficial palmar fascia harder to lift up than dorsal superficial fascia?
It is attached by strong bands of connective tissue to the palmar aponeurosis, a thickening of the deep fascia.
78
What is the thenar eminence?
This is the rounded thickening at the base of the thumb.
79
What is the hypothenar eminence?
This is the rounded thickening at the base of the pinky
80
Why is there less fixation between skin and deep fascia at the thenar and hypothenar eminences than elsewhere in the palmar surface of the hand?
This allows the superficial fascia to adapt better to the contours of objects being held, improving grip.
81
What is the function of palmaris brevis?
It lies in the superficial fascia over the hypothenar eminence and wrinkles the skin to improve grip.
82
What does the deep layer of palmar fascia cover?
* Interossei
* Abductor pollicis
83
What does the superficial layer of palmar fascia form?
It forms the palmar aponeurosis which fans out to cover the thenar and hypothenar muscles.
84
What is the palmar aponeurosis?
A trinagular structure at the bases of the fingers with its apex at the central wrist which protects underlying vessels and nerves.
85
What does the palmar aponeurosis give rise to in the four fingers?
Slips which are continuous with the sheaths of the flexor tendons
86
What is Dupuytren's contracture?
This is where the medial part of the palmar aponeurosis and fibrous flexor sheath in the little and ring finger become contracted leading to progressive flexion of the metacarpophalangeal and interphalangeal joints.
87
What is the role of fibrous sheaths in the phalanges?
They hold the flexor tendons close to the bones, preventing bowstringing and ensuring their pull produces movement at the interphalangeal joints.
88
What are fibro-osseous canals?
These are shallow groove on the anterior surface of the phalanges which the synovial sheaths of flexor tendons run through. They are held in the groove by fibrous flexor sheaths.
89
What are the 3 compartments of the palmar surface of the hand?
* Thenar compartment
* Intermediate compartment
* Hypothenar compartment
90
What is found in the intermediate compartment of the palm?
* Long flexor tendons
* Lumbricals
91
What type of joints are the common carpometacarpal joints?
Plane synovial joints
92
Which ligaments reinforce the joint capsule of carpometacarpal joints?
* Dorsal carpometacarpal ligaments
* Palmar carpometacarpal ligaments
* Interosseous ligaments
93
What is the structure of dorsal carpometacarpal ligaments?
They are a series of fibrous bands spanning from the distal row of carpal bones to the base of each metacarpal which each metacarpal generally receiving two bands (The second metacarpal from trapezium and trapezoid, the third from trapezoid and capitate etc with the fifth receiving a single band from hamate).
94
What is the structure of the palmar carpometacarpal ligaments?
They are fibrous bands similarly arranged to the dorsal carpometacarpal ligaments except the base of the third metacarpal receives three bands from trapezoid, capitate and hamate.
95
What are the interosseous ligaments of the hand?
Short ligaments between capitate and hamate and the third and fourth metacarpals.
96
What are intermetacarpal joints?
These are plane synovial joints linking the bases of adjacent metacarpals (from 2-5).
97
What is the structure of the metacarpal head?
It is biconvex, broaders anteriorly than posteriorly and has hyaline cartilage across its surface.
98
What is the structure of the base of the proximal phalanx?
It hs a biconcave base that articulates with the metacarpal head.
99
What type of joint are the metacarpophalangeal joints?
Condyloid
100
What are the deep transverse metacarpal ligaments?
These are ligaments which connect the palmar ligaments of the metacarpophalangeal joints (2-5) and preventing their separation.
101
What type of joints are the interphalangeal joints?
Synovial hinge joints
102
What are the origins of flexor digitorum profundus?
* Medial aspect of coronoid process of the ulna
* Superior three-quarters of anterior and medial surfaces of the body of ulna
103
What are the insertions of flexor digitorum profundus?
Palmar aspects of the distal phalanges of all four fingers
104
Which actions are mediated by flexor digitorum profundus?
Finger flexion
105
Which nerves innervate flexor digitorum profundus?
Median nerve (C8-T1 nerve roots)
106
Which blood vessels supply flexor digitorum profundus?
* Ulnar artery
* Ulnar collateral artery
* Ulnar recurrent artery
* Anterior interosseous artery
107
Which structures are deep to flexor digitorum profundus?
* Ulna
* Interosseous membrane
* Pronator quadratus
108
Which structures are superficial to flexor digitorum profundus?
Flexor digitorum superficialis
109
How can you strengthen flexor digitorum profundus?
* Wrist curls
* Grip strength trainers
110
How can you stretch flexor digitorum profundus?
Finger extensions with palm flat on table
111
How do you palpate flexor digitorum profundus?
1. Place the patient's elbow on a table
2. Palpate the olecranon and move inferiorly down the ulna
3. Push onto the anterior surface of the ulna
4. Ask the patient to make a tight fist and your fingers should be pushed out
112
What type of muscle is flexor digitorum profundus?
Fusiform
113
What is the path of flexor digitorum profundus?
It travels to the mid forearm and splits into four tendons which then separate into one along the index finger and the other three. These then pass through the flexor retinaculum via the common flexor sheath.
114
What do the tendons of flexor digitorum profundus give rise to?
The lumbrical muscles
115
What are the origins of flexor digitorum superficialis?
* Medial epicondyle of the humerus (via a common flexor tendon)
* Sublime tubercle of ulna
* Proximal half of the anterior border of radius
116
What are the insertions of flexor digitorum superficialis?
Palmar aspects of the phalangeal bones of all four fingers
117
Which actions are mediated by flexor digitorum superficialis?
Finger flexion
118
Which nerves innervate flexor digitorum superficialis?
Median nerve (C7-T1 nerve roots)
119
Which blood vessels supply flexor digitorum superficialis?
* Ulnar artery
* Ulnar recurrent artery
* Radial artery
120
Which structures are deep to flexor digitorum superficialis?
* Flexor digitorum profundus
* Flexor pollicis longus
121
Which structures are superficial to flexor digitorum superficialis?
* Flexor carpi radialis
* Flexor carpi ulnaris
* Palmaris longus
122
Which structures are lateral to flexor digitorum superficialis?
Brachioradialis
123
How do you strengthen flexor digitorum superficialis?
* Wrist curls
* Grip strength trainers
124
How do you stretch flexor digitorum superficialis?
Finger extensions with palms flat on a table
125
How do you palpate flexor digitorum superficialis?
1. Palpate the medial epicondyle of the humerus
2. Ask your patient to perform a one hand clap and you will see the muscle firing and you can follow it down as far as the flexor retinaculum
126
What type of muscle is flexor digitorum superficialis?
A broad fusiform muscle
127
What is the path of flexor digitorum superficialis?
It travels to the mid-forearm, splits into four tendons which separate into one to the index finger and three to the other fingers. They all then pass through the flexor retinaculum via a common flexor sheath.
128
What are the origins of the lumbrical muscles?
Tendons of flexor digitorum profundus supplying that finger (or to two fingers for the two medial muscles)
129
What are the insertions of the lumbricals?
Lateral aspect of the extensor expansion of their respective fingers
130
Which actions are mediated by the lumbricals?
* Flexion of the metacarpophalangeal joints
* Extension of the interphalangeal joints
131
Which nerves innervate the lumbricals?
* Medial nerve (lateral two lumbricals)
* Ulnar nerve (medial two lumbricals)
132
Which blood vessels supply lumbricals?
* Palmar arch artery
* Palmar digital artery
* Dorsal metcarpal artery
133
Which structures are posterior to lumbricals?
* Abductor pollicis
* Interossei
134
Which structures are anterior to lumbricals?
Palmar aponeurosis
135
How do you strengthen lumbricals?
Place your palm flat on the table and try to slide fingertips towards your palms while keeping fingers straight (knuckles rise towards the ceiling)
136
How do you stretch metacarpophalangeal joints?
Push metacarpophalangeal joints into extension and flex your interphalangeal joints
137
How do you palpate lumbricals?
1. Ask the patient to place their palm face up on the table
2. Perform resisted phalangeal flexion and you can strum the tendons of flexor digitorum superficialis in the palm beneath each phalanx
3. This is directly superficial to the origins of th lumbricals and can be followed up the lateral side of eac proximal phalanx
4. Ask the patient to perform resisted metacarpophalangeal flexion and interphalangeal extension and you may be able to feel the muscles firing
138
What type of muscles are the lateral lumbricals?
Unipennate
139
What type of muscles are the medial lumbricals?
Bipennate
140
What are the origins of extensor digitorum?
Lateral epicondyle of the humerus via a common extensor tendon
141
What are the insertions of extensor digitorum?
Dorsal aspects of the bases of the middle and distal phalanges
142
Which actions are mediated by extensor digitorum?
Extension of all four fingers
143
Which nerves innervate extensor digitorum?
Posterior antebrachial interosseous nerve (C7-C8 nerve roots)
144
Which blood vessels supply extensor digitorum?
* Radial recurrent artery
* Posterior interosseous artery
145
Which structures are anterior to extensor digitorum?
* Supinator
* Abductor pollicis
* Extensor indicis
* Extensor pollicis longus
146
Which structures are lateral to extensor digitorum?
Extensor carpi radialis brevis
147
Which structures are medial to extensor digitorum?
* Extensor digiti minimi
* Extensor carpi ulnaris
148
How do you strengthen extensor digitorum?
* Reverse wrist curls
* Eccentric wrist curls
149
How do you stretch extensor digitorum?
Make a fist and maximally flex the wrist
150
How do you palpate extensor digitorum?
1. Pronate your patient's arm
2. Perform resisted finger extension and you can follow any of the tendons all the way up to the lateral epicondyle
151
What type of muscle is extensor digitorum?
Long fusiform muscle
152
What is the path of extensor digitorum?
It splits into four tendons in the distal wrist, passes deep to extensor retinaculum and passes through a shared sheath with
