MSK Flashcards
What portion of the anterior shoulder can look like a rotator cuff tendon tear and is where the biceps tendon leaves the groove?
rotator interval
what is the normal width at the AC joint under ultrasound?
6mm
what two structures are the ultrasound landmarks when evaluating the elbow for potential joint injection?
lateral epicondyle and trochlea of humerus
what structure is located between the lateral epicondyle and the humerus trochlea on the posterior elbow?
posterior fat pad
when injecting the elbow, what approach should be used?
transverse , in plane, insert needle over the lateral epicondyle
describe the location of the popliteus in relationship to the LCL?
deep to the LCL
what structure is found in the femoral groove above the lateral meniscus and under the LCL?
popliteus
on a wrist ultrasound, what structure is located between the extensor digitorum tendon and the joint?
dorsal radiocarpal ligament
an abscess greater than what size is unlikely to resolve with antibiotics only?
> 3cm
what is ultrasound posterior enhancement?
brighter appearance of tissue deep to an area of fluid due to increased ultrasound transmission
what type of artifact can be used to identify foreign body in soft tissue?
shadow
ultrasound of fluid filled round structures, such as cysts, can have what type of artifact at the edges?
linear shadowing
when scanning the proximal biceps tendon, what slight orientation of the probe should be used to avoid anisotropy?
slight cephalad tilt
hypoechoic clefts will be seen in the short axis view of what RTC tendon? why?
subscapularis - due to interdigitation of muscle (hypoechoic) with tendon (hyperechoic)
ultrasound of which RTC tendon will have a birds beak appearance in long axis view?
supraspinatus
the supraspinatus inserts onto what facet of the greater tuberosity?
superior facet
why is articular cartilage anechoic on ultrasound?
water rich
the impingement view for supraspinatus is more in what direction compared to the standard long axis view of the tendon insertion?
more lateral
anechoic fluid collection anterior to the proximal biceps tendon can be indicative of what?
SASD bursitis
in a case of calcific tendinopathy of the RTC tendons, there will be what artifact deep to areas of calcification?
shadowing
if you see biceps tendon edema collection, what else is on the ddx?
glenohumeral joint effusion
fluid both in the biceps tendon sheath and the bursa is 95% sensitive for what?
rotator cuff tendon tear
t/f local CSI of the carpal tunnel delays the need for surgery at 1 year
true
as you follow the median nerve down the forearm toward the wrist, the median nerve will have what trajectory before returning to midline at the carpal tunnel?
radial deviation
what deep muscular structure of the forearm is a landmark for proximal median nerve scanning?
pronator quadratus
the bony carpal tunnel exists between what two bony structures?
scaphoid and pisiform
the flexor tendons have what directional relationship to the median nerve at the carpal tunnel?
deep to median nerve
what tendon structure overlies the scaphoid at the carpal tunnel?
FCR
what ultrasound artifact can you use to differentiate tendons from the median nerve?
aniostropy
what is a normal cross sectional area of the median nerve at the carpal tunnel?
< 11mm squared
what cross sectional area of the median nerve is considered severe carpal tunnel?
> 17mm squared
in the proximal forearm, the median nerve is between what two muscle layers?
FDS / FDP
which rotator cuff tendon has a wide footprint insertion?
subscapularis
