LECTURE 14: Wrist and hand Flashcards
how many bones in wrist and hand?
29 (half of all bones are in hands, wrist, ankle and feet)
* 2 forearm bones
* 8 carpal bones
* 5 metacarpal bones
* 14 finger bones
multiple functions of hand/wrist:
- expression/communication
- motor/manipulative
- sensory input: (temp, texture, shape, etc)
joints of the forearm, wrist, hand complex
DRUJ
radio-carpal joint
intercarpal joints
midcarpal joints
5 CMC joints
5 MCP joints
IP joints (PIP, DIP)
DRUJ closed packed position
5 degrees supination
DRUJ open packed position
10 degrees supination
DRUJ is a _ _ joint
capsular pattern:
uniaxial, pivot joint 1 DOF
pain at extreme pronation/supination
neutral ulnar variance is normal. (radius and ulnar is 1 mm from each other or less)
what is the + and - variance?
(-): ulna is shorter, more than 2 mm prox to radius
(+): ulna is longer, more than 2 mm distal to radius
What is ulnar variance at the DRUJ? What population gets this often?
- determined by age, genes, load, prime for medial and lateral elbow pathologies
- gymnasts (+ variance)
CPP for Radio-Carpal joint
OPP for Radio-carpal joint
CPP: full ext w/ radial deviation
OPP: neutral w/ slight ulnar deviation
capsular pattern for radio-carpal joint
Capsular pattern: flex motion loss = ext motion loss
proximal row carpal bones
scaphoid
lunate
triquetrum
pisiform
carpal bones
distal row
trapezium
trapezoid
capitate
hamate
intercarpal joints
CPP
OPP
capsular pattern?
CPP: full extension
OPP: neutral to slight flexion
Capsular pattern: none
intercarpal joints
passive vs active structures
bony congruency
ligaments
but NO ACTIVE STRUCTURES
*look for passive stability
midcarpal joints
CPP
OPP
capsular
CPP: full extension w/ ulnar deviation
OPP: neutral to slight flexion w/ ulnar deviation
Capsular pattern: flex motion loss = ext motion loss
midcarpal joints
passive vs active structures?
Passive structures
Bones (congruency)
Dorsal and palmar interosseous ligaments
Active structures
None
1st CMC joint is a _ joint with _ DOF
sellar joint: 3 DOF
1st CMC joint
CPP
OPP
capsular
CPP: full opposition
OPP: midway between abduction and adduction and between flex/ext
capsular: ABD > extension loss
passive structures involved in 1st CMC joint
capsule large, LOOSE
at least 5 ligaments
active structures involved in 1st CMC joint
AbdPL, AbdPB, EPL, EPB, FPL, FPB, AddP, OP mm.
other CMC joints are _ joints with _ DOF
PLANE
1 DOF
2nd and 3rd CMC JOINTS are relatively _
4th and 5th CMC joints are relatively _
2/3: immobile
4/5: mobile (grasp)
MCP joints
CPP
OPP
Capsular
CPP: full opposition (1st), full flexion (2nd-5th)
OPP: slight flexion
Capsular pattern: flex loss > ext loss
MCP joints are _ with _ DOF
condyloid
2 DOF
PIP joints are _ with _ DOF
uniaxial hinge joints
1 DOF
PIP joints passive structures
- bony congruency
- collateral ligaments
- dorsal hood, volar plate
PIP joints active structures
FDS tendons
ED tendons
PIP joints:
CPP
OPP
capsular pattern
CPP: full extension
OPP: slight flexion
Capsular pattern: flex loss > ext loss
DIP joints are _ joints with _ DOF
uniaxial hinge joints
1 DOF
DIP joints
CPP
OPP
capsular
CPP: full extension
OPP: slight flexion
Capsular pattern: flex loss > ext loss
DRUJ ligaments
- Dorsal radio-ulnar ligament
- palmar
Which tendons have pulleys?
Which are flat, which are round?
flexors: pulleys, round
extensors: no pulleys, flat
what lives in snuffbox, why do we care?
scaphoid
fractures
median nerve passes through _ except _
carpal tunnel
except palmar branch passes over carpal tunnel
