Hand and Wrist RMSK Flashcards
Wrist joints
radiocarpal, midcapal, distal radioulnar
Contens of carpal tunnel
Median nerve, FDS, FDP, FPL
Roof of carpal tunnel is the
flexor retinaculum
Carpal tunnel inlet
scaphoid and pisiform
Carpal tunnel outlet
Trapezium and Hamate
Dorsal compartments how many? Name all
six 1 (APL,EPB) 2(ECRL,ECRB) 3 (EPL) 4(EDC, EIP) 5(EDMinimi) 6(ECU)
Where does the FDS split and insert
splits at PIP joint, inserts at middle phalanx
Insertion of Extensor Digitorum tendon
middle phalanx as a central band.
Nerve fascicle appearance
hypoechoic fasicle. hyperechoic surrounding connevtive tissue
Median nerve appearance tunnel vs forearm
Hypoechoic at tunnel, hyperechoic forearm
Where does the palmar cutaneous branch of the median nerve go
superficial to flexor retinaculum and ULNAR to FCR tendon
Thenar motor branch landmark
from palmar ulnar aspect of radial division of median nerve. extending proximal between the APB and FPB.
Palmaris longus
directly superficial to median nerve
Nerves found in dorsal extensor compartment 1
superficial radial nerve
Nerve found at the 4th dorsal compartment
Posterior interosseous nerve
ECU tendon has a normal thin hypoechoic longitudinal cleft
not a tear
ECU tendon located outside groove
50% of the time is outside.. still normal
Extensor retinaculum measurement
1.7mm thick and 23mm wide in Cross section
What plane is the distal radioulnar joint seen?
transverse
What plane is the radiocarpal and midcarpal joint recess seen
sagittal
Landmark for finding the scapholunate ligament
distal to Listers tubercle
Superficial to the dorsal scapholunate ligament what structure?
dorsal radiocarpal ligament is seen.. common site for wrist ganglion
What comprises TFCC
cartilage, meniscus, ECU tendon sheath, ulnar and dorsal radiocarpal ligament
vascular landmark near superficial radial nerve
cephalic vein
Appearance of pulleys on ultrasound
trilaminar.. superficial reflectiv surface . hypoechoic pulley, hyper reflective surface of adjacent tendon sheath
A1 pulley location
MCP
A2 pulley location
PP
A3 pulley location
PIP joint
A4 pulley location
MP
Where can you find the ulnar collateral ligament of the thumb? landmark
MP joint and PP..
structure superficial to UCL of thumb
adductor pollicis aponeurosis- moves with flexion of IP joint
What dynamic test for UCL
valgus for ulnar ligaments and varus for radial ligaments
Joint recess distenstion anechoic
simple fluid
Joint recess distention NOT anechoic what are your considerations?
compelx fluid and synovial hypertrophy
Complex fluid characteristics
compressible, swirling echoes, NO INTERNAL FLOW ON DOPPLER
Synovial hypertrophy considerations
LITTLE compressibility, No displacement. + with internal flow on doppler , hypoechoic or (less frequyently iso or hyper compared to adjacent subdermal fat)
typical characteristic of a ganglion cyst
MULTILOCULAR & NON COMPRESSIBLE
active inflammatory synovitis
hypoechoic with hyperemia on color doppler imaging
RA hand and wrist protocol
three joints of each wrist ( radioulnar, radio carpal, midcarpal) MCP joints of each index and long fingers PIP of index and long fingers
what is paratendinitis
inflammation of a tendon that has no tendon sheath
Tenosynovitis erosions in RA region in hand
ulnar styloid
RA early assessment ofwhich tendons
ECU and second flexortendon
proximal intersection syndrome involvement and location
4-8cm PROXIMAL to listers. APL EPB and ECRB and ECRL (1st and 2nd dorsal)
accessory muscles of hand
accessory ABDUCTOR DIGITI MINIMI - Ulnar nerve entrapment, Extensor digitorum brevis manus, palmaris longus
normal CSA of median nerve
< 6 if >12mm CTS…
Measurement of bifid median nerve
combined CSA has difference of 4mm2 comparing PQ and DISTAL carpal tunnel
Hypothenar hammer syndrome cause
thrombus
fatty median nerve mass
fibrohamaroma median nerve
Compression of superficial radial nerve at distal forearm syndrome
wartenburg
Appearance of abnormal TFCC
abnormal hypoecho, thinning or absence.
Interosseous membrance bet. radius and ulna tears called
essex-lopresti injury ( comminutedradial head fracture at elbow with interosseous injury and distal radioulnar joint disruption)
Difference between fracture and cortical irregularity
step-off deformity is specific (radiographic correlation is essential) hyperemia, and point tenderness
ganglion cyst echogenic considerations / artifact
usually with increased through transmission