Mod 2: Lecture 4 - Forearm and Wrist Flashcards
1
Q
Axillary Artery —>____
A
- brachial artery
- at the inferior border of the teres major muscle, the axillary artery changes name to become the brachial artery
- subclavian –> axillary –> brachial
2
Q
Brachial Artery
A
- Brachial Profunda
- — a branch of the brachial artery that comes off in the upper arm
- — runs deep into the arm to supply the deep tissue/muscle
- Terminal Branches: where the brachial artery splits at the elbow region
- — Radial Artery
- — Ulnar Artery
- — these run into the forearm
3
Q
Ulnar Artery Branches
A
- common interosseous artery branches off the ulna
- common interosseous artery –> anterior interosseous artery + posterior interosseous artery
- — supply the deep tissue/muscle of the forearm
4
Q
Elbow anastomosis formed by….
A
- ulnar collaterals (vessels from the ulnar artery)
- radial and ulnar recurrent arteries
- ensures a good blood flow to the arm at all times
5
Q
Superficial Palmar Arch
A
- formed from the ulnar artery as it goes into the hand
- a curve of vessel in the palm that is closer to the fingers than the wrist
- vessels coming off of it
- — supply 2 vessels each to the pinky, ring, and middle finger
- — supply 1 vessel to the index finger
6
Q
Deep Palmar Arch
A
- formed by the radial artery
- vessels coming off of it
- — supply 2 vessels to the thumb
- — supply 1 vessel to the index finger
- a curve of vessel in the palm that is closer to the wrist than fingers
7
Q
Upper Extremity: Venous Drainage
A
- a dorsal venous network drains the superficial and deep venous palmar arches
- — back of the hand
- superficial to the metacarpus , the network is prolonged proximally
- — the network goes just above the wrist where it enters into other veins
- — lateral side (thumb side): cephalic vein
- — medial side (pinky side): basilic vein
8
Q
Basilic and Cephalic veins –>
A
- Median cubital vein is the communication between the basilic and cephalic veins in the cubital fossa
- — the median cubital vein branches across the arm at the elbow to connect these two parallel veins
- Basilic –> origin of the axillary vein
- Cephalic –> termination of the axillary vein
9
Q
The radial and ulnar styloids limit ____
A
- lateral deviation of the wrist
- the styloids are the pointed projections on the distal end of the bones
10
Q
Clinical Correlation: Colle’s Fracture
A
- 70% in post-menopausal women
- — protective effect on bone density of estrogen
- — so old ladies are more likely to fall and try to break it with their hands
- — but they end up snapping their wrist
- distal radius fracture with dorsal displacement of distal fragment
- — the end of the radius breaks and is pushed up toward the dorsal side of the hand/wrist
11
Q
Clinical Correlation: Smith Fracture
A
- reverse of Colle’s fracture
- occurs when there is force to a flexed wrist
- — such as in sports if a player falls while holding a ball and lands on the back of his wrist
- distal radius fracture with palmar displacement of distal fragment
- — the end of the radius breaks and is pushed up toward the palmar side of the hand/wrist
12
Q
Carpal Bones
A
- Two Rows: Proximal and Distal
- — “So Long to Pinky, Here Comes The Thumb”
- — clockwise from thumb on volar surface, beginning in proximal row
- carpal bones are very tightly packed, close proximity to each other
- distal radial articulates with the carpals
- distal ulna does not articulate with them
13
Q
Proximal Row Of Carpal Bones
A
- Proximal row approximates with the radius
- — is closer to arm
- —- scaphoid, lunate, triquetrum, pisiform ( Lat- Med)
- — the scaphoid is on the thumb side
- — you cannot see the pisiform from the dorsal surface of the hand, you can only see it in a palmar view
- “So Long to Pinky,…”
14
Q
Distal Row of Carpal Bones
A
- Distal row approximates with metacarpals
- — is closer to fingers
- — hammate, capitate, trapezoid, trapezium (Med - Lat)
- — hammate is under the pinky bc this little piggy goes to the market
- “…. Here Comes The Thumb.”
15
Q
Hand Osteology
A
- Styloid Process of Radius
- Styloid Process of Ulna
- Metacarpal
- Proximal Phalange
- Middle Phalange
- Distal Phalange
16
Q
Hand Osteology
- Styloid Process of Radius
- Styloid Process of Ulna
- Metacarpal
A
- tip of the triangular distal end of the radius
- little pointed thing sticking out of the distal end of the ulna
- bones in the hand, distal to the carpals, proximal to the phalanges
- there are 5, one connecting each finger to the wrist
- — numbered from 1 to 5, starting with the thumb (1) and ending in the pinky (5)
- each has a base (proximal end) and head (distal end)
17
Q
Hand Osteology
- Proximal Phalange
- Middle Phalange
- Distal Phalange
A
- the row of phalanges that is closest to the metacarpals
- — there are 5 of them, one in each finger - the row of phalanges that is in between the proximal and distal phalanges
- — where the middle knuckle in your fingers is
- — there are 4 of them, one in each finger except the thumb - the tips of the fingers, after the last knuckle
- — small little bones
- — there are 5 of them, one in each finger
18
Q
Palmar Arches
A
- formed by bony structures, ligaments
- Two Transverse Arches
- One Longitudinal Arch
- Functions:
- — balance stability and mobility –> arches are stable structure
- — increase surface contact of palm –> more sensory feedback
- — position thumb for function –> put thumb in opposition to fingers
19
Q
Transverse Palmar Arches
A
- there are two
- Proximal: runs across the bases of the metacarpals
- Distal: runs across the heads of the metacarpals
20
Q
Longitudinal Palmar Arch
A
- only one
- runs through the long axis (from wrist to fingertip) of the third digit (middle finger)
21
Q
Articulations: Radiocarpal
A
- between distal radius and proximal carpals
- condyloid type
- — moves in two planes
- wrist flexion/extension
- — sagittal plane, bending forward and back
- wrist abduction and adduction
- — coronal plane, moving sideways in and out (right and left)
22
Q
Articulations: Midcarpal
A
- between proximal and distal row of carpal bones
- plane synovial joint
- gliding motions between carpals
23
Q
Arthrokinematics:
- Flexing the wrist down, like reaching into a bag of chips
- Wrist Extension, moving the hand up, fingers point up, like going for a high five (without raising your arm)
A
- full range of motion at the wrist requires movement at both the radiocarpal and midcarpal joints
- so for wrist injuries, you must address movement at both joints
- 60% radiocarpal movement
- 40% midcarpal movement
- 60% radiocarpal movement
- 40% radiocarpal movement
- 60% midcarpal movement
- 40% radiocarpal movement
24
Q
Distal Radioulnar Joint
A
- between the distal ends of the radius and ulna
- pivot synovial joint
- supination/pronation
- separated from the joint space of the radiocarpal joint by an articular disc
25
Q
Stabilizing Ligaments
A
- Collateral Ligaments
- Retinaculum Ligaments
26
Q
Collateral Ligaments
A
- stabilizing ligaments
- Radial Collateral Ligament
- — between radius and carpals
- — on the side of the first digit (thumb)
- — prevents deviation to the ulnar side/ pinky
- Ulnar Collateral Ligament
- — between the ulna and carpals
- — prevents deviation toward the radial side/thumb
27
Q
Retinaculum Ligaments
A
- stabilizing ligaments
- broad bands of fibrous connective tissue that stabilize the wrist and prevent “bowstringing” of the tendons of extrinsic muscles of the hand
- Extensor Retinaculum: dorsal
- Flexor Retinaculum: ventral
28
Q
Extensor Retinaculum Ligament
A
- dorsal side of wrist
- from distal radius to pisiform and triquetrum
- horizontally across the proximal end of the wrist
29
Q
Flexor Retinaculum Ligament
A
- ventral side of wrist
- from pisiform and hammate to scaphoid and trapezium
- horizontally across the middle of the carpal bones
30
Q
Carpal Tunnel
A
- anatomical space between the flexor retinaculum ligament and the carpal bones
- tendons of some muscles (FDS, FDP, FPL) and the main branch of the median nerve pass through the carpal tunnel
- — one branch of the median nerve (palmar cutaneous branch) does not pass through
- ulnar nerve and artery do not pass through the tunnel
31
Q
Muscles Acting on the Wrist: Extensors
A
- Extensor Carpi Radialis Longus (Radial Nerve)
- Extensor Carpi Radialis Brevis (Radial)
- Extensor Carpi Ulnaris (Radial)
- all three are in the posterior compartment, so innervated by the same nerve
32
Q
Muscles Acting on the Wrist: Flexors
A
- Anterior Compartment
- — main flexors of the wrist
- — Flexor Carpi Radialis (Median)
- — Flexor Carpi Ulnaris (Ulnar)
- Palmaris Longus (Median)
- — absent in 10 - 25% of people
- — weak flexor of the wrist
33
Q
Muscles Acting on the Wrist: Extensors
- Attachments
- Action
- Innervation
A
- lateral epicondyle of humerus (thumb side)
- base of metacarpals
- — ECRL: 2nd metacarpal
- — ECRB: 3rd
- — ECU: 5th
- lateral epicondyle of humerus (thumb side)
- wrist extension
- radial nerve
34
Q
Clinical Note: Lateral Epicondylitis
A
- repeated forceful flexion and extension of the wrist may strain the attachment of the common extensor tendon
- — flexion: muscle stretches
- — extension: muscle contracts
- — attachment: lateral epicondyle of humerus
- producing inflammation of the periosteum of the lateral epicondyle
- — lateral epicondylitis
- test by resisting wrist extension while pushing on lateral condyle at elbow
35
Q
Muscles Acting on the Wrist: Flexors
- Attachements
- Action
- Innervation
A
- medial epicondyle of the humerus (pinky side)
- FCR/FCU: base of metacarpals
- PL: fascia of the palm, over the metacarpals
- medial epicondyle of the humerus (pinky side)
- wrist flexion
- FCR: median
- FCU: ulnar
- PL: median
- FCR: median
36
Q
Clinical Correlation: Dupuytren’s Contracture
A
- a benign, slowly progressive condition causing contracture (or shrinking) of the palmar fascia
- — makes it impossible to fully extend the hand
- — needs to have the tissue surgically extended to gain full motion
- has no clear etiology or pathogenesis
- may be hereditary
- — commonly present in males of Irish/Welsh descent
37
Q
- Wrist Abduction
2. Wrist Adduction
A
- Radial Deviation
- — coronal plane, swinging the wrist out to the lateral side
- occurs as a result of co-contraction of both the ECRL and FCR
- Radial Deviation
- Ulnar Deviation
- — coronal plane, swinging the wrist in to the medial side
- occurs as a result of co-contraction of both the ECU and FCU
- Ulnar Deviation
