3. Introduction
The shoulder is one of the most sophisticated and
complicated joints of the body:
• It has the greatest range of motion than any joint
in the body
• To allow so much movement the joints need to
be 'free' to move, therefore the shoulder should
be 'unstable' compared to other joints of the
body; However a series of complex ligaments and
muscle help in stability.
7. Glenohumeral Joint
– Ball and socket synovial joint
– Very mobile
– instability
– 45% of all dislocations !!
– Joint stability depends on multiple factors (static
and dynamic stabilizers)
10. Fibrous Capsule
Loose for maximum movements
Gaps:
• Anteriorly: allows communication between synovial membrane
and subscapularis bursa.
• Posteriorly: allows communication with infraspinatus bursa.
Synovial Membrane
• Attached around the glenoid labrum.
• Lines the capsule.
• Attached to articular margins of head of humerus.
• Covers intracapsular area of surgical neck.
• Communicates with 2 bursae through gaps in capsule.
• Invests long head of biceps in a tubular sleeve.
• Glides to and fro during adduction and abduction.
19. Radiography
• Initial investigation of choice for all shoulder problems.
• Can detect most fractures, dislocations, calcific
tendinitis and other skeletal causes of pain such as
arthritis and bone tumors
• Different situations require different types of plain
films (AP/Lateral/Axillary views):
– Impingement views in clinically suspected impingement
syndrome and/or rotator cuff tears to detect subacromial
spur
– Axial or anterior oblique views in trauma
20. AP :
Routine view
• AP relative to thorax
• Suboptimal view of
Glenohumeral joint
• Good view of AC
joint
21. AP View:
External Rotation
Greater tuberosity & soft tissues profiled and better
visualized
22. AP View:
Internal Rotation
May demonstrate Hill-Sachs lesions
26. USG
• Preferred initial modality in suspected RTC
pathologies
• > 90 % sensitive and specific for RTC tears
• Comparable to MRI in evaluation of full
thickness rotator cuff tears
• Bony pathologies not well seen
27. • Advantages:
– no ionizing radiation,
– no contrast agent,
– relatively inexpensive,
– readily available
– Dynamic evaluation
– Guided aspiration / injection possible
• Limitations:
– Less sensitive for detecting partial thickness rotator
cuff tears
– Cannot accurately evaluate the labral-ligamentous
complex.
28. Shoulder USG Protocol
(Radiology: Volume 260: Number 1—July 2011 n radiology.rsna.org)
• Step 1 - Biceps brachii tendon, long head
• Step 2 - Subscapularis and biceps brachii
tendon, subluxation/dislocation
• Step 3 - Supraspinatus and rotator interval
• Step 4 - Acromioclavicular joint, subacromial-subdeltoid
bursa, and dynamic evaluation for subacromial
impingement
• Step 5 - Infraspinatus, teres minor, and posterior labrum
34. CT
• Superior to plain radiographs in evaluation of
complex fractures and fracture-dislocations
involving the head of the humerus
• Allows planning of treatment of complex
proximal humeral fractures
35. CT
1) Glenoid 9) Teres minor
2) Humerus 10) Triceps
3) Deltoid 11) Pec major
4) Infraspinatus 12) Pec minor
5) Scapula 13) Biceps (long)
6) Supraspinatus 14) Biceps (short)
7) Clavicle 15) Teres major
8) Subscapularis 16) Latissimus
37. MRI
• Highly accurate for evaluation of rotator cuff
pathologies
• Indicated when further investigation of rotator cuff
pathology is needed.
• Advantages:
– No ionizing radiation
– Non-invasive
– Multi-planar imaging
– Demonstrates other lesions such as ACJ osteoarthritis
and avascular necrosis.
– Comprehensive display of soft tissue anatomy
– Demonstration of the causes for impingement
– Useful in characterization and staging of bone tumors
38. MRI Technique
-T1 and T2 FS
-Oblique Coronal -T1 and T2 FS
-Oblique Sagittal
-T2 FS and GRE
-Axial
45. Arthrography
• PREREQUISITES:
• Obtain signed consent.
• RISKS:
• Infection, Pain, Hematoma
• MATERIALS:
• 22G 3 ½” needle
• 25G 1 ½” needle
• 5 cc syringe with lidocaine for skin anesthesia
• 20 cc syringe with combination of 1% lidocaine
• Omnipaque 300
• Gadolinium contrast (if performing MR)
46. Shoulder MR or CT Arthrography
• Place the patient supine
• Target the junction of the middle and inferior thirds of humeral head just lateral to the medial
cortex of humeral head.
• Local lignocaine given
• Fill a 20 cc syringe with the proper contrast solution and fill connecting tubing being sure to
eliminate all bubbles.
• Advance a 22 G spinal needle until contact bone at target site.
• Pull back 1 mm and turn bevel toward humeral head. Advance and feel the syringe drop into the
joint.
• MR Arthrogram:
• Inject 12 cc of a solution of 5 cc normal saline, 5 cc Omnipaque 300, 10 cc 1% lidocaine, and 0.1
cc gadolinium.
• Instruct the patient on the importance of the ABER position and how it can help the surgeon
figure out how to fix them.
• CT Arthrogram:
• Inject 12 cc of a solution of 5 cc normal saline, 10 cc Omnipaque 300, and 5 cc 1% lidocaine
• Helical CT should be performed with thinnest slices available, preferably in a single breath hold in
both internal and external rotation.
47. MR arthrography
• Most accurate and first line imaging modality for
defining:
– Rotator cuff pathology
– Labral/capsule abnormalities in gleno-humeral
instability
• Superior depiction of partial-thickness tears
compared to conventional MRI.
• Disadvantages : invasive, limited availability and
high expense.
48. CT arthrography
• Alternative for assessment of gleno-humeral
instability (usually following dislocation) only
when MRI is contraindicated or unavailable
• Allows accurate evaluation of capsule / labral
disorders
• Disadvantage – invasive, radiation
52. Rotator cuff tendinopathy
Also known as -
• Rotator cuff tendinosis
• Definition – collagenous
degeneration of rotator
cuff tendons, most
commonly
supraspinatus (SST)
54. MRI
• T1W – thickened heterogeneous tendons with
intermediate signal intensity
• T2W – low to intermediate signal
• FS PD and STIR – heterogeneous tendons with
increased signal intensity
– Hyperintense effusion (glenohumeral joint)
– Hyperintense bursitis ( subacromial / subdeltoid )
• Type III (hooked) acromion
• MR arthrography – no cuff defect identified
55.
56. HRUS
• Thickened hypoechoic
• Tears directly visible
• Less sensitive for partial thickness tears
• Advantage – allows dynamic evaluation with
pain correlation
57. Differentials
• Partial tear –
– T2 (without fat sat) shows diminished / intermediate signal
intensity in tendinosis as compared to a hyperintensity of a
true cuff tear
• Calcific tendinitis –
– thickened tendon with decreased signal on all sequences
– Form of tendinopathy
– Hyperintense surrounding edema on T2WI
• Intratendinous cyst –
– Well defined , usually oval
– Hyperintense cyst on T2WI
• Magic angle artifact –
– Increased signal at curved portion of tendon
– 55 degrees to external magnetic field
– Affects biceps and SST tendon and labrum
58. Rotator cuff tears
• Clinical –
– Trauma (acute / chronic micro-trauma)
– Adults > 4o with impingement
– Collagen vascular diseases
– Partial more painful than complete tears !!!!
TYPES -
• Partial –
– supraspinatus most common
– Types – bursal surface
interstitial (not seen on arthroscopy)
articular surface
• Complete –
– supraspinatus most common
– Extends from bursal to articular surface
60. Radiographic findings
Findings associated with impingement and
degenerative changes
• Acromial spurs
• Type III (hooked) acromion
• Humeral head arthritic changes at greater
tuberosity
• AC degenerative changes
61. MRI
Incomplete defect in tendon filled with joint fluid +/- granulation
tissue
• T1WI –
– thickening of RTC tendons
– intermediate signal
– Calcifications
– hypointense bone impaction (Hill-Sachs) in case of anterior
dislocation
• T2WI –
– Fluid signal intensity filling an incomplete gap in tendon
– Fluid in subacromial bursa
– Increased signal on FS PD (sensitive for partial tears)
– Retraction and degeneration of tendon edges (bursal or articular)
62. • PC T1 –
– enhancement of the granulation tissue
• MR arthrography –
– Contrast may fill the tear if articular surface of the
tendon communicates with joint
63.
64.
65. USG
• Decreased echogenicity and thinning in
affected region
• Loss of convexity of tendon / bursa interface
in bursal surface tears
• Calcific foci in tendons
66. Differentials
• RTC tendinopathy
• Full thickness tear without visible
communication – closed by granulation tissue
/ fibrosis / adhesions
• Intratendinous cyst – can be associated with
partial tears
• Calcific tendinitis – hypointense on all
sequences
68. Full thickness tears
Etiology – similar to partial tears
Associated with –
– Hill Sach’s deformity (anterior dislocation)
– Biceps tendinosis / tears / SLAP lesions with micro
instability
69. Radiography
• Acromial spurs
• Type III (hooked) acromion
• Humeral head arthritic changes at greater
tuberosity
• AC degenerative changes
• Superior humeral head migration
70. MRI
• T1WI
– Thickened indistinct tendon
– Tear edges not delineated on T1
– Calcifications (i/c/o calcific tendinitis)
• T2WI
– Hyperintense fluid signal filling a gap in the tendon (T2 and
FS PD)
– Bald spot sign – hyperintense fluid ‘bald spot’ within
hypointense tendon
• On sag and axial T2
– Fluid in subacromial bursa
• Retraction and degeneration of tendon edges
• Sometimes associated with fatty atrophy of muscles (fat
signal on T1)
72. USG
• Focal tendon interruption
• Fluid filed gap (hypoechoic)
• Loss of convexity of tendon / bursa interface
• Tendon retraction
• Uncovered cartilage sign
73. MRI Rotator cuff tear grading
- Dr Yuranga Weerakkody and Dr Frank Gaillard et al.
• grade 0 : normal
• grade I : increased T2 signal with normal morphology
• grade II : increased T2 signal with abnormal morphology
(thickening, or irregularity of the tendon)
• grade III : defined tear (e.g. partial or full
thickness, complete or incomplete)
75. Rotator interval tears
• What is rotator interval ??
– Tunnel through which long head of biceps travels
from its origin at the supraglenoid tubercle
• Rotator interval tears – tears in the capsule
between the supraspinatus and subscapularis
tendons
• Can be classified as subtype of RTC tears
76. MRI
• T1 –
– Thickened rotator interval
– Biceps tendinosis and subluxation
• T2 –
– Visible tear in rotator interval
– Associated tear of SST may be present
– FS PD sag images are useful to detect abnormal fluid extension
across rotator interval
• MR arthrography –
– Leakage of contrast through the tear in RI
– Intact SST and SSC
79. Internal impingement
• Definition - Degeneration and tearing of posterior SST
and anterior infraspinatus tendons (undersurface /
articular surface) due to impingement by postero-
superior labrum and humeral head
• Postero-superior glenoid impingement (PSGI)
• Overhead throwing activities – athletes (throwers)
• Dynamic compression – occurs during abduction (> 120
degrees), retropulsion and extreme external rotation
(ABER)
80. MRI
• T1 –
– Thickened posterior SST and anterior IST (tendinosis)
– Postero-superior labral irregularity (fraying)
– Tear in postero-superior labrum (can be avulsed)
– Postero-superior humeral head irregularity
• T2 –
– Hyperintense signal on articular surface of posterior SST
and anterior IST
– Hyperintense signal (FS PD) in postero-superior humeral
head, humeral head chondromalacia
– Fraying +/- tear of PSGL
81. Axial FS PD
Synovitis, labral fraying, sclerosis at
posterosuperior glenoid, cystic changes in
posterolateral humeral head
82. • MR arthrography –
– Postero-superior labral fraying / tear
demonstrated by contrast outline
– ABER imaging shows undersurface tears
– Chondromalacia outlined by contrast
83. • Best diagnostic clue - triad of damage at
1. Undersurface of RTC
2. Postero-superior labrum
3. Humeral head
• Differentials –
– Subacromial impingement (history differs)
– SLAP without RTC pathology
85. Rotator cuff calcific tendinitis
• Calcium Hydroxyapatite deposition disease (HADD)
• Calcifying bursitis
• Not typical Ca++ of degenerative disease of tendons, but crystalline
Ca++
• Pathology – deposition of Calcium Hydroxyapatite in RTC tendons
• Etiology – Avascular change, trauma, abnormal Ca++ metabolism
• Housewives and clerical workers more affected
• Location – SST > IST > TM > SSC
• Peri-articular soft tissues like capsule, bursae may be involved
86. Stages / classification
(Moseley)
• Silent
• Mechanical – intra bursal or sub bursal rupture
Physical restriction of movements
• Adhesive peri-arthritis – tendinitis
bursitis
87. • Radiography
– Calcific deposits
– Internal rotation demonstrates posterior tendons
well (IST and TM)
– Axillary view and scapula ‘Y’ view helpful
• CT
– Better localization of calcium deposits
– Dense, granular, well demarcated calcifications
88. MRI
• Globular decreased signal mass (on all pulse
sequences) in RTC tendons
• Often surrounded by edema / partial tear
(hyperintense)
• No involvement of articular cartilage
• Hydroxyapatite deposits may have exactly same
signal as normal cuff tendons
• T2*GRE is helpful as calcifications bloom and
increase sensitivity
90. Differentials
• Degenerative calcification in torn tendon
– Usually smaller calcifications
– In older age group
– Different chemical composition
• Loose bodies
– Chondral defects seen
– Articular OA changes
• Osteochondromatosis
92. Parsonage - Turner syndrome
• Idiopathic denervation of the shoulder musculature
• More than one nerve may be involved
• Mainly affects the LMN of the brachial plexus and / or individual
nerves or nerve fibers
• Etiology –
– Immune mediated reaction against nerve fibers
– Trauma, infection, surgery, vaccination, systemic illness
• Pathology –
– Degenerative changes in affected muscles
– Early and subacute – swollen muscle belly
– Chronic - fatty atrophy
93. CT
• Acute / subacute cases – mildly increased bulk
of muscles
• Chronic cases – fatty density in involved
muscles
94. MRI
• MRI abnormalities appear usually after 2 weeks
• T1 –
– Early – decreased signal (edema)
– Chronic – muscle atrophy with streaky fat signals (fatty
atrophy)
• T2 –
– Early – increased signal intensity, enlarged muscle bulk
– Chronic – atrophic muscles
– Nerve distribution pattern +/-
• PC T1 – muscle belly enhance in early stages
100. Labral cyst
• Cyst arising from labral / capsular tear / capsular
diverticulum
• Etiology – cyst arising due to break in integrity of
joint
• 3-5 % of labral tears associated with labral cysts
• Slow growing, original tear may heal
• Associated abnormalities –
– Instability (non healed)
– SLAP (superior labrum anterior to posterior)
– Denervation of SST and IST (compression)
101. MRI
Common location – adjacent to postero-superior labrum
funneled between SST and IST (path of
least resistance)
• T1 –
– Decreased signal intensity cystic mass
• T2 –
– Hyperintense cystic lesion
– Often multiloculated
– Arising from / immediately adjacent to the labrum / capsule
– Degenerative changes in SST / IST (suprascapular nerve)
– Labral tear
• MR arthrogrpahy –
– Cyst filled with contrast
102.
103. Differentials
• Neoplasm
– Internal enhancement
– Not associated with labral / capsular tear
• Normal vessel –
– plexus in suprascapular notch
– Can be enlarged in CHF
106. Sublabral foramen
• Relative lack of attachment of anterosuperior
labrum to the glenoid rim in anterior superior
quadrant
• MRI –
– Hyperintense fluid signal (mostly linear) on T2
undermining the antero-superior labrum
– Should not be confused with SLAP lesion
– Bankart’s lesion – below the equator (antero-
inferior)
107. Axial FS PD - anterior labrum directly
attached to the hyaline cartilage
108. Buford complex
• Complete absence of antero-superior labrum
+
• Thick cord-like middle glenohumeral ligament
(MGHL) anterior to the anterosuperior glenoid
rim
120. Bankart lesion
• Avulsion of inferior glenohumeral labral
complex (IGHLC)
• Etiology –
– IGHLC is a ‘weak link’ among the static stabilizers
of young shoulder
– Occurs after initial anterior dislocation in young ( >
90% cases are < 40 years)
121. Asociated abnormalities
Bony Bankart – osteochondral fracture in some
cases
Hill Sachs lesion – fracture at posterolateral
superior humeral head
Partial / complete RTC tears
122. Radiography
• Subglenoid / subcoracoid dislocation
• Glenoid rim fracture
CT
• Arthrography – contrast extending into the
labral tear
123. MRI
• T1 –
– Hypointense edema / sclerosis at antero-inferior glenoid
– Glenoid rim fracture (sag and axial more useful)
• T2 –
– Labrum – torn with hyperintense fluid, within or underlying
labrum
– fracture line at glenoid rim
– Fracture at postero- lateral humeral head
– Thickened and hyperintense IGHLC (acute dislocation)
– ABER view better for visualization
• T2*GRE – greater sensitivity for abnormal intra-labral
signal as compared to FS PD or PD
124.
125.
126. Prognosis –
• Recurrent instability (improper healing)
Rx -
• Conservative with a sling
• Surgical or arthroscopic repair for repeated
dislocations
128. Perthes lesion
• Bankart variant (uncommon 5-10 % of Bankart
lesions)
• Detached IGHLC with intact scapular
periosteum, which is stripped medially
• Etio-pathology similar to Bankart lesion
129. MRI
• T2 –
– Subtle linear increased signal intensity at the base of
usually non-displaced labrum
– Bankart fracture
– Redundant hypointense periosteum
• STIR –
– provides improved contrast for visualization of medially
stripped scapular periosteum
• MR arthrography – in ABER (arm placed behind the
head)
132. ALPSA lesion
Anterior Labro-ligamentous Periosteal Sleeve
Avulsion
• Components -
– Anterior IGHLC avulsion from antero-inferior
glenoid
– Intact periosteum
– Medial displacement and inferior shift of the
anterior IGHLC
133. MRI
• T2 –
– Medial displacement of IGHLC on axial and coronal
images
– Hyperintense in acute cases
– Hypointense in chronic cases
– Hyperintense edema and hemorrhage in joint capsule
and adjacent soft tissues
• MR arthrography –
– Medial and inferior displacement of labrum
– Chronic cases with re-synovialisation show minimal
displacement
136. GLAD lesion
Glenoid Labrum Articular Disruption
• Definition - Partial tear of anterior glenoid
labrum with adjacent articular cartilage defect
• Young physically active patients
• Pain on IR and adduction
137. MRI
• Irregular increased signal intensity on T2 / FS PD
within the anterior labrum and adjacent hyaline
articular cartilage
• Labral tear is typically not detached
• Chondral defect well seen on FS PD (not well seen
on T2)
• MR arthrography –
– Contrast filling the labral tear
– Contrast may fill the chondral defect
– ABER – demonstrates partial labral tears by placing
stress on capsular ligamentous attachments
138.
139. HAGL
• Humeral Avulsion of Glenohumeral Ligament
• Inferior GHL involved
• CT arthrography – extravasation of contrast through humeral
interface defect into anterior para-humeral soft tissue
• MRI –
– discontinuous capsule at humeral interface (anatomic neck
attachment of IGL)
– Capsule assumes ‘J’ shape on coronal images (normal axillary
pouch has ‘U’ shaped contour )
• MR arthrography – extravasation of contrast inferior to
axillary pouch
142. • Radiography –
– Mineralization adjacent to posterior glenoid
– Better visualized on axillary view
• CT arthrography –
– Posterior labral tear
• MR –
– Crescent shaped areas of ossification
– Adjacent to posterior labrum
– Labral tear
– T2*GRE show blooming
– MR arthrography – posterior labral tear
143.
144. Posterior labral tear
• Reverse Bankart
• Secondary to posterior dislocation
• Posterior band of IGHLC ‘weak link’ among static
stabilizers in most shoulders
• Radiography and CT –
– Posterior glenoid rim fracture
– Trough sign – reverse Hill Sachs on anterior humerus
creating a trough / defect
– Lesser tuberosity avulsion fracture
149. Tendinosis
• Degeneration of long head of biceps
• Long head of biceps –
– LHBT originates at supra glenoid tubercle
– Passes through the antero-superior joint
– Enters the humeral bicipital groove
• Chronic micro-trauma
• Acute trauma (rare cause)
• Accompanies RTC disease (especially impingement)
• Common with subacromial impingement (30-60%
association)
• Biceps tenosynovitis may accompany
150. • Radiography - Sclerosis at the superior aspect of
bicipital groove (chronic cases with instability)
• USG –
– Thickened hypoechoic tendon
– Tears often directly visible
– Allows dynamic evaluation
151. MRI
• T1 –
– Thickened intermediate signal intensity tendon
– SST tendinopathy
• T2 –
– Thickened (> 5 mm), irregular frayed tendon
– Increased signal
– FS PD and PD more sensitive for tendinosis
– T2 more sensitive for fraying / tears
– SST tendinopathy
• MR arthrography – thickened filling defect
(enlarged tendon)
154. Biceps tendon tear
• Tendinosis predisposes
• Associated with SST tear
• Distal tendon edge may retract into upper arm
155. • CT arthrography –
– Bicipital groove filled with contrast
– Absence of normal ‘filling defect’
• MRI –
– Irregular stump at superior aspect of joint
– Partial or complete hyperintense fluid gap in the
tendon (T2)
– Synovitis (PD)
159. SLAP lesions
• Superior Labrum Anterior to Posterior lesions / tears
• Location –
SLAP I – superior labrum
SLAP II – superior labrum + biceps anchor
SLAP III - superior labrum
SLAP IV– superior labrum + biceps tendon
SLAP V to IX have also been classified
• Pathology –
– Focal fraying and degeneration of labrum at BLC in SLAP I
– Complete anterior to posterior extension in SLAP II - IV
160. MRI (T2)
• SLAP I –
Intermediate to hyperintense labral degeneration without labral tear
Represents intra substance degeneration
Can be age related normal finding
• SLAP II –
Linear hyperintense fluid signal between superior labrum and superior pole of
glenoid (> 5 mm displacement of labrum and biceps anchor on coronal images)
• SLAP III –
Identify fragmented superior labrum into two separate components on sag and
cor images through BLC )
Bucket handle tear through the meniscoid superior labrum
• SLAP IV –
Split of the biceps tendon with hyperintense linear longitudinal tear with
avulsion
164. Rx
• Conservative –
– NSAIDs
– PT
• Surgical –
• Type I – debridement
• Type II – stabilize, bioabsorbable tack (sutures)
• Type III – debridement
• Type IV – suturing of biceps , reattachment of
labrum
166. Biceps tendon dislocation
• Biceps instability
• Definition – dislocation of long head of biceps
tendon from bicipital groove
• Etiology –
– Due to disruption of stabilizing ligaments (RTC tears)
– SSC and coracohumeral ligament are major stabilizers
of biceps
– Shallow bicipital groove predisposes
167. MRI
• T1 –
– Increased signal intensity fat fills the bicipital groove
• T2 –
– Tendon not in groove
– Mostly displaced medially
– Flattened / thickened (if previous tendinosis)
– SSC partial / complete tear
• T2*GRE – more sensitive for visualization of
hypointense biceps fiber
• MR arthrography – empty groove, tendon sheath filled
with contrast
168.
169. USG
• Empty groove
• Displaced biceps tendon hypoechoic and
edematous
Best diagnostic clue –
• Empty bicipital groove with oval structure
outside the groove with hypointense signal on
all pulse sequences (MRI)
174. Subacromial impingement
• Physical impingement with repeated micro trauma
Etiology –
• Primary extrinsic - Subacromial spur, AC OA
• Type III (hooked) acromion
• Lateral down sloping of anterior acromion
• Os acromiale
• Secondary extrinsic – no osseous abnormality of
coracoacromial arch
Rx – conservative, Acromioplasty
180. MRI
• Hooked acromion on sagittal images with
decreased subacromial outlet
• Lateral down sloping seen on coronal images
• Subacromial space < 7 mm considered increased
risk
• Changes of RTC tendinopathy
• Partial tears may be seen
• Bursitis
• Thickened coracoacromial ligament
184. Os acromiale
• Unfused acromial ossification center
• Normally fuses by 25-30 years
• Mature bone with synchondrosis between os
and acromion
• +/- mobile distal acromion
• Can cause impingement
• Rx – conservative, preacromian
excison, stabilization
185. Types
• Basi-meta (type C)
• Meta-meso (type A)
• Meso-pre (type B –
most common)
186. MRI
• Age > 25-30 years
• Unfused bony fragment
• Corticated structure with medullary fat in it
(hyperintense)
• Hypointense sclerosis at its margins
• Pseudo double AC joint (axial and cor)
• T2*GRE – unfused ossification demarcation
(hyperintense)
189. AVN
• AVN / osteonecrosis
• It is ischemic death of cellular elements of bone
and marrow
• Etiology –
steroids, alcohol, smoking, trauma, collagen
vascular diseases, arteritis, storage disorders
(Gaucher’s), idiopathic
• 2nd most common (after femoral head)
192. Class Description
I Normal (can be seen on MRI)
sclerosis in superior central
II
portion of the head
crescent sign - caused by
III subchondral bone collapse; may
have mild flattening
significant collapse of humeral
IV
articular surface.
V degenerative joint disease.
Cruess X-ray Classification of AVN Humeral Head
193. MRI
• Supero-medial part of head most commonly involved
• Serpiginous hypointense lines (T1)
• Double line sign – increased signal in the center of the
line (vascular granulation tissue) with decreased signal on
both sides (T2 and T2*GRE)
• Non specific edema
• Subchondral collapse and cysts
• FS PD – more sensitive for ischemic edema in acute cases
194. • PC T1 – the granulation component of ‘double
line sign’ may enhance
• MR arthrography – contrast extend into the
necrotic bone
Best diagnostic clue –
Supero-medial involvement
Double line sign on T2W
197. Osteochondral injuries
• Definition - Injury to articular hyaline cartilage
+/- underlying bone fracture, bone trabecular
injury or associated reactive stress response
• Tidemark zone is the weakest part of articular
cartilage – between overlying cartilage and
subchondral bone
• Rotational forces – direct trauma – cause
cartilage injury – secondarily involve the
underlying bone
198. MRI
• T1 –
– Subchondral sclerosis and edema
• T2, FS PD and STIR –
– Increased signal in articular cartilage
– Underlying bone edema (hyperintense)
• T2*GRE – only sensitive to large chondral defects
• MR arthrography – contrast fills the chondral defect
Best diagnostic clue –
• Increased signal in articular cartilage
199. ‘Outerbridge’ classification of articular cartilage
injuries
• Grade 0 – normal
• Grade 1 – chondral softening and swelling (increased
signal on FS PD)
• Grade 2 – partial thickness defect, not reaching
subchondral bone / < 1.5 cm in max dimension
• Grade 3 – just reaching upto the subchondral bone / >
1.5 cm
• Grade 4 – exposed bone / full thickness cartilage loss
205. MRI
• Subchondral cyts
• Osteophytes (marrow signal extends into it)
• Generalized thinning of hyaline cartilage, with
occasional focal defects
• Synovitis
• Loose bodies
• Posterior glenoid wear leads to increased
retroversion of glenoid
• PC T1 – synovial enhancement in synovitis
206. Rheumatoid arthritis
• Synovium – articular cartilage – subchondral bone
• Marginal erosions (more at greater tuberosity)
• Bilateral symmetrical involvement
• Diffuse synovial thickening
• Joint effusion
• Bone erosions
• Loss of joint space not prominent
• Mild superior migration of humeral head (RTC rupture)
– decreased space between HH and acromion
• Clavicular erosions predominate at AC joint
• Tapered and resorbed distal clavicle (chronic cases)
209. Quadrilateral space syndrome
• Entrapment neuropathy (compression) of axillary nerve in
quadrilateral space
• Boundaries –
• Superiorly – teres major
• Inferiorly – teres minor
• Medially – long head of triceps
• Laterally – humerus
• Best diagnostic clue –
• Increased signal in teres minor and deltoid on FS PD or STIR
(denervation)
• Streaky decreased signal intensity (fibrosis)
210. Suprascapular / Spinoglenoid notch
• Impingement of suprascapular nerve
• Location -
– SSN at superior glenoid
– SGN at posterior glenoid
• Best diagnostic clue –
• Increased signal in SST and IST on FS PD or STIR
(denervation)
• Streaky decreased signal intensity (fibrosis)
212. Dislocation
Types
• Shoulder dislocations are usually divided
according to the direction in which the humeral
exits the joint:
• anterior : > 95 % (subcoracoid)
• posterior : 2 - 4 %
• inferior (luxatio erecta) : < 1 %
217. Tumors
• Proximal humerus –
– Simple bone cyst
– Aneurysmal bone cyst
– Giant Cell Tumor of Bone
– Osteosarcoma (common)
– Enchondroma (relatively common)
– Periosteal chondroma (just proximal to insertion of deltoid)
– Osteochondroma
– Chondroblastoma
– Chondromyxoid fibroma
– Metastases
• Scapula –
– Osteochondroma
– chondrosarcoma: affects the shoulder girdle
218. Role of interventional radiology
• US and fluoroscopy guided intra-articular and
bursal infiltration (steroids, other drugs)
• Percutaneous needle removal of calcific deposits
• Capsular distension/infiltration of adhesive
capsulitis
• Therapeutic aspiration of suprascapular or
spinoglenoid cysts (to relieve suprascapular nerve
compression)
• Percutaneous radio-frequency treatment of
symptomatic bone metastases under CT guidance
219. Conclusion
• Plain radiographs are useful as an initial screening test with patients
with shoulder pain.
• Ultrasound may be used for diagnosing rotator cuff disease (> 90 %
sensitive and specific for tears).
• CT useful only in cases of trauma and to detect associated bony
abnormalities
• MRI is the ‘modality of choice’ for most of the shoulder pathologies.
• MR arthrography or CT arthrography is required for investigating
instability