Download MRI - Penn Medicine

U Penn Diagnostic Imaging: On the Cape
Chatham, MA – July 11-15, 2016
MRI of
the
Shoulder
Viviane Khoury, MD
Assistant Professor of Radiology
University of Pennsylvania
MRI of the shoulder: indications
• Rotator cuff
abnormalities
(impingement)
• Labroligamentous/
biceps pulley
abnormalities
(glenohumeral joint
instability, internal
impingement)
Rotator Cuff
Pathology/
Shoulder
Impingement
Syndrome
Rotator cuff tendon pathology
• Tendinopathy (tendinosis)
• Partial tears
• Complete tears
Tendinosis
• Non-inflammatory
ischemic or
degenerative process
• Increased signal on
short TE (T1, PD,
GRE), less than fluid
on long TE
•Pitfalls: magic angle,
volume averaging
normal
Where do cuff tears occur?
• Most originate in supraspinatus
– Anterior critical zone
– May extend anteriorly to
subscapularis
– May extend posteriorly to
infraspinatus, teres minor
• “Rim rent” (supra or
infraspinatus)
• Posterior supraspinatus/
infraspinatus junction
• Isolated infraspinatus
• Isolated subscapularis
(dislocations)
Complete cuff tear
• Direct signs:
– Discontinuity of tendon
– Defect filled with fluid
– Tendon retraction
• Indirect signs:
– Fluid in subacromialsubdeltoid bursa; joint
effusion
– Fluid in subcoracoid bursa
– Muscle atrophy, fatty
infiltration
Classification of complete tears
according to size
•Small: < 1cm
•Large: 3-5 cm
•Medium: 1-3 cm
•Massive: >5 cm
Tear morphology (arthroscopic classification)
Crescent
U-shaped
L-shaped
Burkhart SS, Lo IKY. Arthroscopic rotator cuff repair. J Am Acad
Orthop Surg. 2006 Jun;14(6):333-46
Full-thickness supraspinatus tear
with delamination
Cor FS T2
Acute vs chronic full-thickness tear
Muscle atrophy and fatty infiltration
No atrophy
Sag T1
Severe atrophy
SS
IS
Sscap
TM
“Rim rent” tears
• Partial tear at
insertion on G.T.
cor
• Younger patients
• ? Angulation of
fibers at insertion
• +/- Debridement
sag
Supraspinatus rim-rent tear
cor
sag
Partial thickness tears
• Fluid signal that does not
span full thickness of
tendon
• May involve
– Articular surface (most)
– Bursal surface
– Intrasubstance
• Fiber discontinuity,
fraying, change of tendon
caliber
Bursal surface partial
thickness tear
Cor
Sag
Grading of partial tears
• Grade 1: < 3mm (<25%)
• Grade 2: 3-6 mm (25-50%)
• Grade 3: > 6mm (>50%)
(normal cuff: 10-12 mm thick)
• Grade influences surgical
decision
• Grading may be difficult with
arthroscopy
“PASTA” lesion
(Partial articular surface supraspinatus
tendon avulsion)
49M
delamination
Grade 1 partial tear
MR-arthrography improves
conspicuity of partial tears
Low-grade articular surface partial
supraspinatus tear (27M athlete)
Fat sat T2
Fat sat T1
Bursal surface partial tear:
(MR-arthrography pitfall)
FS T1
FS T2
Rotator interval : biceps pulley
• Between supraspinatus
and subscapularis:
– SGHL
– Coracohumeral
ligament
– LHB
• Role in glenohumeral
joint stability
Habermeyer P, et al. Anterosuperior impingement of the shoulder as a result of pulley
lesions: A prospective arthroscopic study. J Shoulder Elbow Surg 2004
Rotator cuff interval pathology
•Acute trauma
•Chronic anterior
instability
•Diffuse degenerative
process
•Adhesive capsulitis
Morag Y, Jacobson JA, Shields G, et al. MR arthrography of rotator interval, long head of
the biceps brachii, and biceps pulley of the shoulder. Radiology 2005 Apr;235(1):21-30
N
Acute rotator
interval tear
Sag FS T1
Morag Y, Jacobson JA, Shields G, et al. MR arthrography of rotator interval, long head of
the biceps brachii, and biceps pulley of the shoulder. Radiology 2005 Apr;235(1):21-30
RI and biceps brachii instability
• Biceps dislocations are
accompanied by
ligamentous pulley
tears
• Different patterns of
LHB dislocations
depending on lesions
of CHL, SGHL,
subscapularis
Shoulder Impingement Syndrome:
Contributing factors
•
•
•
•
Acromion morphology
AC joint OA
Os acromiale
Thick coracoacromial
ligament/ subacromial
enthesophyte
• Post-traumatic bony
deformity
• Muscular hypertrophy
• …
MRI of calcific tendinitis
Cor T1
Cor FS T2
MR of the Glenoid
Labrum
Capsulolabral anatomy
Glenohumeral joint instability
• Anterior (95%)
• Posterior, superior,
inferior,
multidirectional (5%)
Bankart lesion
• Detachment of
anteroinferior
labrum by anterior
band IGHL
• Disrupted scapular
periosteum
• “GLOM”
Woertler K, Waldt S. MR imaging in sports-related glenohumeral instability.
Eur Radiol 2006 Dec:16 (12):2622-36
Perthes lesion
• Non-displaced
labral detachment
• Stripping of scapular
periosteum
• Best seen with MRarthrography and ABER
position
Wischer TK, Bredella M A, Genant HK, et al. Perthes lesion (a variant of the Bankart lesion): M R imaging
and M R arthrographic findings with surgical correlation. AJR Am J Roentgenol. 2002 Jan;178(1):233-7.
ALPSA
(anterior labroligamentous periosteal
sleeve avulsion)
• Anteroinferior
labrum pulled by
IGHL anterior
band
• Periosteum intact
Chronic ALPSA
Hill-Sachs
• Bony Bankart
• HAGL lesion
(humeral avulsion of
[inferior]
glenohumeral
ligament)
Glenoid labrum articular
disruption (GLAD) lesion
Woertler K, Waldt S. M R imaging in sports-related glenohumeral
instability. Eur Radiol 2006 Dec;16(12):2622-36
“SLAP” lesions
(superior labrum anterior to
posterior)
• Young athletes (baseball, tennis,
volleyball)
• Sx: sensation of instability, click, pain
• Several types (4 to 10), depending on
– extent of labral tear
– long head of biceps involvement
– glenohumeral ligament involvement
sag
Normal
sublabral recess
SLAP lesions
SLAP lesion with extension
into SGHL
cor
ax
Summary: MR-arthrography
indications
• Main indication is evaluation of labrum /
intra-articular biceps
• Limited in rotator cuff pathology to
– Post-operative cuff
– Inconclusive MR (e.g. partial tears in
young/athlete)
– Suspected rotator interval tears
– Suspected posterosuperior impingement
Summary: Rotator cuff
To include in MRI interpretation:
• Condition of tendons
• Size, extent, morphology of cuff tears
• Involvement of contiguous structures
(RI, LHB)
• Contributing factors for impingement
• Muscle atrophy and fatty infiltration
Summary: Instability and internal
impingement
• MR arthrography essential; +/- ABER
To include in MR-arthrogram interpretation:
• Location and extent of labral tear (use clock
face or quadrants)
• Abnormalities of LHB and GHLs
• Presence and size of Hill-Sachs, Bankart
lesions
• Associated rotator cuff tears (always include
a fluid-sensitive sequence)