elbow, wrist, hand Flashcards
1
Q
in the frontal plane, how much valgus is there?
A
6 degrees
2
Q
in the sagittal plane, how much anterior rotation is there?
A
30 degrees
3
Q
what kind of joint is the humeroulnar
A
hinge
4
Q
how is the humeroulnar joint formed
A
- concave trochlear notch of ulna
- convex trcohlea of humerus
5
Q
how does the humeroulnar joint glide
A
in the same direction
6
Q
what is the carrying angle of males and females
A
M: 11-14
F: 13-16
7
Q
how is the humeroradial joint formed
A
- convex capitulum of humerus
- concave head of radius
8
Q
how does the humeroradial joint glide
A
in the same direction for flexion and extension
9
Q
which motions does the humeroradial joint do
A
- flex/ext
- rotation of radius
10
Q
which motions does the humeroulnar joint do
A
flex ext
11
Q
what is the elbow capsule
A
- thin, but strong
- does not respond well to injury or immobilization
- forms thick scar tissue resulting in flexion contractures
12
Q
describe the ulnar (medial) collateral ligament
A
- triangular shaped
- medial epicondyle to coronoid process and olencarnon
- 3 components: anterior, posterior, transverse/oblique
- provides stability against valgus stress
- important role between 20-130 degrees of motion
13
Q
describe the anterior band of the ulnar (medial) collateral ligament
A
- strongest and stiffest elbow collateral lig
- becomes taught in terminal extension
- stabilizes elbow against valgus stress between 20-120 degrees
- secondary restraint at end range flexion beyond 120
14
Q
describe the posterior band of the ulnar (medial) collateral lig
A
- weakest band
- taught beyond 55 of elbow flexion
- secondary restraint to valgus stress at lesser degrees of flexion
- an equal co-restraint with anterior band at terminal flexion (especially in overhead athlete in counteracting valgus stresses)
15
Q
describe the transverse/oblique band of the ulnar (medial) collateral lig
A
- originates and inserts on ulna
- little role in elbow stablity
- deepends socket for trochlea
16
Q
describe ulnar collateral lig injury
A
- most commonly anterior band ruptured
- varied repair and reconstruction techniques
- autograft of palmaris longus
17
Q
describe the radial (lateral) collateral lig
A
- fan shaped
- lateral epicondyle and blends with annular lig
- consistent tension throughout arc of flexion
- restraint against varus load at elbow
- also primary restraint again posterolateral instability
18
Q
what is posterolateral instability
A
- of the radial head
- if you distrupt radial/lateral collateral ligament then the radial head can sublux out of annular ligament in a postlat direction
19
Q
describe the annular ligament
A
- provides 80% of the articular surface of humeral radial joint
- stabilizes radial head
- maintains relationship of radial head with ulna
- forms prox radioulnar joint
- permits pronation/sup
20
Q
desribe osteokinematics of pronation
A
- radial head convex
- radial notch on ulna concave
- roll and glide of convex radius on concave ulna
- radial head rolls and glides in OPPOSITE direction
-radial head rolls ant and glides post
21
Q
desribe osteokinematics of supination
A
- roll and glide of convex radius and concave ulna
- radial head rolls and glides in OPPOSITE direction
-radial head rolls post and glides ant
22
Q
what kind of joint configuration is the distal radioulnar joint
A
ovoid
23
Q
how is the distal radioulnar joint formed
A
- head of ulna convex
- ulnar notch on radius concave
-radius moving on ulna:
convex= roll and glide in same direction
24
Q
what are the functions in conjunction with PRUJ
A
pron/sup
- occur simultaenously at both prox and distal radioulnar joints
- also requires rotation of radius at humeroradial joint in annular lig
25
what is the distal radioulnar joint articulation
- head of ulna
- TFCC
- ulnar notch radius
26
what is the radiocarpal/ulnocarpal joint articulation
- radius
- TFCC
- prox row carpals (not pisiform)
27
what is the midcarpal joint articulation
-prox and distal row
28
what is the TFCC
triangular fibrocartilage complex
29
what are the components of the TFCC
- biconcave fibrocartilage disc
- palmar ulnocarpal lig
- ulnar collateral lig
- dosral and volar radioulnar ligs sometimes
30
what is the function fo the TFCC
- major stabilizer DRUJ
- binds distal radius and ulna
- provides dual articular surface
- separates radioulnar from radiocarpal joint
- cushion- ulnar sided force transmission
31
how do TFCC injuries happen
variable
- FOOSH
- extension wtih ulnar compression
- forced radial or ulnar deviation
- strong distratcion force
32
what is the axis of rot for flex/ext
coronal axis between lunate and capitate
33
what is the axis of rot for rad/ulnar dev
sagittal between lunate and capitate
34
what is the axis fo rot for circumduction
polyaxial
35
in the midcarpal joint, what is the ulnar compartment
capitate and hamate
| convex
36
in the midcarpal joint, what is the radial compartment
trapezium and trapezoid
- concave in dorsal/volar direction
- convex in radial/ulnar direction
37
which motion does the midcarpal joint prefer
extension
38
describe the ring system
- bones within each row tethered together by interosseuous ligs
- ring is only complete by addition of midcarpal ligs
- as long as ligaments in tact, carpal bones move together as a unit
39
describe the joint configuration at the radiocarpal/ulnocarpal joints
- flex/ext prox row rolls and glides opposite
- radial/ulnar dev prox row rolls and glides opposite
- RD: scaphoid/lunate flex (rocks)
- UD: prox row extend (twists)
-RD and UD limited in extremes of wrist flex and ext due to lig constraints
40
how many metacarpal bones
5
41
how many phalange bones
14
42
what kind of joint is the 1st carpometacarpal
sellar
43
describe the joint configuration of the distal surface of the trapezium
convex: radial/ulnar
concave: dosral/volar
44
describe the joint configuration of the prox surface of the 1st MC
concave: radial/ulnar for radial abd/adduction
concex: dorsal/volar for palmar abd/add
45
how many degrees of freedom in the thumb
3
46
talk about radial ab/ad in the thumb
MC rolls nad glides in SAME direction
47
talk about palmar ab/ad in the thumb
MC rolls and glides in OPP direction
48
what kind of joint is the thumb
condyloid
49
describe the joint configuration of carpometacarpal joint 2 and 3
difficulty to classify as interlocking articular surfaces prevent movement- stability
50
describe the joint configuration of carpometacarpal joint 4 and 5
- distal surface of hamate: slightly concave
| - prox surface of 4 and 5 metacarpals: slightly convex
51
what do the degrees of freedom allow for
cupping of the hand by slight flexion and IR of metacarples
52
what is the function of the 2-5 fingers volar plates
ext: increases contact surface w MC head
flex: glides prox and prevents tendon pinching
53
talk about the joint configuration of metacarpophalangeal joints 2-5
ovoid
distal surface of metacarpals: biconvex
prox surface of phalanges: concave
54
describe flex/ext of phalanx
rolls and glides in SAME direction
55
describe ab/ad of phalanc
rolls nad glides in SAME direction
56
describe the joint configuation of interphalangeal joints 1-5 and thumb MP joint
true synovial hinge joints
- distal surface of prox phalanx: convex
- prox surface of distal phalanx: concave
