MRI of Shoulder

Question 1

rotator cuff is composed of the tendons of four muscles that converge on the greater and lesser tuberosities of the humerus, namely:

Answer 1

supraspinatus, infraspinatus, subscapularis, teres minor

Question 2

of the rotator cuff muscles, this most commonly causes clinically significant problems and is the one that is most commonly surgically treated

Answer 2

supraspinatus

Question 3

lies just superior to the scapula and inferior to the AC joint and acromion. it inserts into the greater tuberosity of the humerus

Answer 3

supraspinatus

Question 4

2 to 3 centimeters proximal to the insertion of supraspinatus is a section of the tendon called the

Answer 4

“critical zone”

Question 5

critical zone is reported to have ____ and is therfore less likely to heal following trauma

Answer 5

decreased vascularity

Question 6

critical zone of the supraspinatus tendon is a common location for

Answer 6

rotator cuff tears

Question 7

a fibricartilaginous ring that surounds the periphery of the bony glenoid of the scapula

Answer 7

glenoid labrum

Question 8

serves as an attachment site for the capsule and broadens the base of the glenohumeral joint to allow increased stability

Answer 8

glenoid labrum

Question 9

tears and detachment of the glenoid labrum most commonly occur from and result in

Answer 9

dislocations or instability of the humerus

Question 10

one of the most common procedurs for shoulder pain whereby the coracoacromial ligament was cut, the anterolateral portion of the acromion was removed, and AC joint osteophytes were resected

Answer 10

Coracoacromial arch decompression

Question 11

most likely source of most rotator cuff problems

Answer 11

intrinsic degeneration

Question 12

treating intrinsic degeneration requires

Answer 12

debriding the abnormal tissue and repairing the cuff

Question 13

rotator cuff is best seen on what view

Answer 13

oblique coronal images that are aligned parallel to the supraspinatus muscle and on oblique sagittal images

Question 14

primary sequence for imaging the rotator cuff

Answer 14

FSE T2W oblique coronal sequence with slice thickness no greater than 5mm and 3 mm

Question 15

MR arthrogram is typically performed by injecting how many cc of saline or gadolinium

Answer 15

10 to 15 cc

Question 16

useful landmark for noting the anterior portion of supraspinatus tendon is the ____, with the anterior most fibers of the supraspinatus found immediately posterolateral to the groove

Answer 16

biccipital groove

Question 17

normal supraspinatus tendon is said to be of what signal

Answer 17

uniformly low in signal on all pulse sequences

Question 18

if the signal in the tendon gets brighter on the T2W, it is abnormal and represents

Answer 18

tendinosis or tendinopathy or a partial thickness tear

Question 19

vast majority of partial tears occur on what side

Answer 19

articular side

Question 20

partial tear that occurs at the insetion of the fibers of the cuff onto the greater tuberosity

Answer 20

rim-rent-tear

Question 21

bone impaction on the posterosuperior aspect of the humeral head and can be seen in patients with anterior instability of the glenohumeral joint. this is called

Answer 21

Hill-Sachs lesion

Question 22

A Hill-Sachs lesion almost always indicated that the anteroinferior labrum will be torn or detached, which is called

Answer 22

Bankart lesion

Question 23

normal labrum appears as

Answer 23

triangular shaped low signal structure on axial image

Question 24

what is larger, anterior or posterior labrum

Answer 24

anterior

Question 25

superior labrum is evaluated in what view

Answer 25

oblique coronal views

Question 26

if joint fluid extends between the bony glenoid and the base of the labrum, a _____ is present

Answer 26

detached labrum

Question 27

often seen in throwing athletes secondary to the pull of long head of biceps that insert on the superior labrum

Answer 27

superior labral tears, called superior labrum anterior to posterior lesions (SLAP)

Question 28

normal variant: an opening beneath the anterosuperior labrum and the bony glenoid that mimics a detachment

Answer 28

sublabral foramen

Question 29

normal variant: consists of an absent anterosuperior labrum in association with a thickened "cord-like" middle glenohumeral ligament

Answer 29

Buford complex

Question 30

seen only on the anterior part of the superior labrum and should be thin and smooth and extends medially

Answer 30

sublabral recess

Question 31

SLAP tear in comparison to sublabral reces

Answer 31

more irregular and extends superiorly and laterally

Question 32

runs in the bicipital groove between the greater and lesser tuberosities and insters onto the superior labrum

Answer 32

long head of biceps tendon

Question 33

suprascapular nerve is made up of branches from the

Answer 33

C4, C5 and C6 roots of the brachial plexus

Question 34

nerve that runs superior to the scapula, from anterior to posterior, just medial to the coracoid process

Answer 34

suprascapular nerve

Question 35

suprascapular nerve innervates the

Answer 35

supraspinatus and infraspinatus

Question 36

this syndrome is most commonly seen in males who are athletic, particularly weight lifters and in this population is almost always associated with a tear of the superior and/or posterior labrum and the subsequent formation of a paralabral ganglion in the spinoglenoid notch

Answer 36

suprascpular nerve entrapment

Question 37

if infraspinatus is smaller than the other muscles and/or has fatty infiltration, _________ is the likely diagnosis

Answer 37

suprascapular nerve entrapment secondary to a ganglion in the spinoglenoid notch

Question 38

if teres minor has fatty atrophy, what is the diagnosis

Answer 38

quadrilateral space syndrome

Question 39

most commonly occurs from fibrous bands or scar tissue in the quadrilateral space impinging on the axillary nerve

Answer 39

quadrilateral space syndrome

Question 40

space that lies between the teres minor superiorly, teres major inferiorly, long head of triceps medially and diaphysis of the humerus laterally

Answer 40

quadrilateral space

Question 41

what nerve traverses the quadrilateral space and innervates the teres minor and deltoid muscles

Answer 41

axillary nerve

Question 42

what muscle is never involved in quadrilateral space syndrome

Answer 42

deltoid muscle

Question 43

image sequence that are useful for identifying muscle edema

Answer 43

oblique sagittal fat-supressed T2 weighted images

Question 44

in about 1% of cases, neurogenic edema is found in muscle groups that correspond to a particular nerve distribution. this is characteristic for

Answer 44

Parsonage-turner syndrome

Question 45

Parsonage-turner syndrome may be associated with

Answer 45

prior vaccinations, viral illness or general anesthesia

Question 46

Parsonage-turner syndrome can affect what nerves

Answer 46

axillary or suprascapular nerve or both