Lec 12 Intrinsic Hand and Wrist Flashcards
Short Muscles
Lumbricals
Palmar Interossei
Dorsal Interossei
Lumbricals
MA: Flex MCP, Extended PIP of 2-5 digit
PA: 1&2 lateral FDP tendons as UNIpennate, 3&4 medial FDP tendons as BIpennate
DA: radial side of extensor expansion of digits 2-5
N: 1&2 Median N C8 T1
3&4 Ulnar N C8 T1
Palmar interossei
MA: Adduct digits 2, 4, 5, assists with MCP flexion and PIP extension
PA: anterior surface of digits 2, 4, 5,
DA: extension expansion, base of proximal phalanges 2, 4, 5
N: Ulnar N (deep branch) C8 T1
DAB
MA: abduct digits 2-4, assist with MCP flexion and PIP extension
PA: adjacent sides of two metacarpals (as bipennate)
DA: extensor expansion and base of proximal phalanges of digits 2-4
N: Ulnar (deep branch) C8 T1
Thenar Muscles
flexor pollicis brevis
abductor pollicis brevis
opponens pollicis
What bone is listers tubercle on?
Radius
Pulley for EPL
What muscles attach to the hook of hamate and pisiform?
Flexor Carpi Ulnaris attaches distally to pisiform and hook of hamate
Abductor Digiti Minimi originates at pisiform
Flexor Digiti Minimi originates at hook of hamate
Opponens Digit Minimi originates at hook of hamate
What muscles attach to the scaphoid?
Abductor Pollicis Brevis,
Flexor Pollicis Brevis,
Opponens Pollicis (Thenar) all originate on scaphoid tubercle (and trapezium tubercle)
How many metacarpals and phalanges are there on one hand?
Metacarpals - 5
Phalanges - 14
List the palmar arches - where are they and what do they help with?
Distal transverse arch - across metacarpals
Proximal transverse arch - across top of metacarpals
Longitudinal arch - runs from the wrist to the tips of the fingers, following the natural curve of the hand
help with grasp
Figure 3.91 Book
Thumb extension - muscles and joints
EPL - CMC, MCP and IP joints
EPB - CMC and MCP joints
APL - CMC joint
Thumb Flexion - joints and muscles
FBL - “flexes phalanges” CMC, MCP, IP joints
FPB - CMC and MCP joints
Thumb abduction - joints and muscles
APL - CMC joint
APB - CMC and MCP joints
Thumb adduction - joints and muscles
Adductor Pollicis
Thumb opposition
Opponens Pollicis
FPB and APB assist
What is the common joint in the thumb for osteoarthritis?
CMC
(trapezium and 1st metacarpal)
Where is no mans zone?
zone II, contains MCP and PIP and the split of FDS which makes it a hard place for surgery because its hard to put back together the split tendon
How are flexor tendon injuries classified?
by zones - 5 distinct zones
Describe the digital pulley system
There are 5 Annular ligaments that run on palmar side of fingers, A1-A5 that stabilize the flexor tendons (FDS and FDP)
A2 - base of proximal phalanx
A4 - middle phalanx
Cruciate ligaments run diagonally in between the annular ligaments, 4 per finger, allowing for movement of tendons
What does the digital pulley system prevent?
Bowstringing = when flexor tendons move away from the digits during flexion
bowstringing decreases finger flexion and weakens grasps
Be able to identify the sagittal band, lateral band, central slip and terminal tendon of the extensor hood
What is trigger finger
real name is stenosing tenosynovitis
inflammation of the A1 ligament that causes finger to get locked in flexed position
What is the floor of the snuffbox?
Arterial artery
Know where to locate the deep palmar branch and superficial palmar arch
What is the parent structure?
deep palmar branch - lower arch on metacarpals (closer to wrist). parent structure is radial artery
superficial palmar arch is the arch farther from the wrist AND on top! parents structure is ulnar artery
Where are the digital branches
arteries at distal phalanx of digits, parent structure is the deep and superficial palmar arches
Mallet finger deformity
Ruptured long extensor tendon (ED or EI)
DIP flexion position
avulsion - tendon is pulled away from the bone
Boxers fracture
neck of the 5th metacarpal (right before the knuckles)
Gamekeepers thumb
(Skiers thumb)
Tear in the ulnar collateral ligament of the thumb which connect thumb to hand (MCP)
know where this is! think adductor muscles location BUT on dorsal side
List the intrinsic hand muscles (categories)
Thenar muscles
hypothenar
adductor compartment
short muscles
Which short muscles of the hand or bipennate and which are unipennate?
1&2 lumbricals are unipennate
3&4 lumbricals are bipennate
PAD is unipennate
DAB is bipennate
What goes through carpal tunnel? What structure creates carpal tunnel?
Transverse carpal ligament (flexor reticulum)
tendons of FDP and FDS
Flexor carpi radialis
Flexor pollicis longus
MEDIAN NERVE
What is and what goes through Guyons canal?
ulnar artery and vein
pisiform and hook of hamate
function of palmer aponeurosis
protects neurovascualr structures
function of synovial sheaths
lubricate tendons
reduce friction during movement
Dupuytrens Contracture
abnormal thickening of palmar aponeurosis
contracture of 4th and 5th digits
this one you CANT force straight whereas trigger finger you can
