06 grainger shoulder pitfalls - leeds msk grainger... · 2019-04-23 · 4/23/19 1 andrew j grainger...
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4/23/19
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Andrew J Grainger
MSK Radiology
Leeds, UK
Norwegian MSK Imaging Seminar 25-26.04.2019 Farris Bad in Larvik
� Positioning & Technique
� Normal anatomy
� Rotator Cuff
� Labrum and Ligaments
� Arm by side
� Neutral to mild external rotation
� Axial scan from ACJ through glenohumeral joint� Sections will also included
Supraspinatus tendon� Use to set up coronal oblique plane
� Difficult to spot on sagittal and coronal images� Can be confusing� One of the reasons for including ACJ
on axial imaging
� Normal acromial apophysis fuses at 25 so can’t diagnose in young
� Problem with internal rotation� Intracapsular biceps & supraspinatus better
shown in neutral or external rotation� Subscapularis poorly visualised� Fat between infraspinatus and supraspinatus
may mimic tendon damage
� Single sequence in internalrotation can be helpful� Puts tension on posterior
capsule� Posterior labroligamentous
injury
� Advantage to angling axials obliquely to be perpedicular to the long axis of the glenoid
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� MRI Diagnosis of Glenoid LabralTear Using the Biceps LabralOblique Sequence (BLO)� Shah et al. ARRS Meeting 2013
Courtesy Dr H Umans, Albert Einstein College of Medicine, Bronx, NY
� ABER can also be helpful
� Takes tension off the supraspinatus� Allows fluid/contrast to enter an articular surface tear
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� Feature of the normal glenoid
� Central location
� Normally flattened posteriorly� Close to infraspinatus insertion
� Hill-Sachs lesion more superior� Look at and above coracoid
� Magic angle effect� Rotator cuff tendons almost inevitably have to pass through 55O to Bo
� Subject to magic angle effect� Abnormal increased signal on short TE sequence
� May simulate tendinosis
� Aim to include long TE (T2) sequence in coronal oblique plane� Also applies to MR-arthrography
� However a small percentage of tendinosis cases will show no increased T2 signal
T1 (fs) T2 (fs) � Frequently see acromial origin of coracoacromial ligament on coronal oblique sequence as dark body� Not osteophyte
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� Can be subtle� Low T1 signal
� Low signal in tendon� May decompress into bursa or
bone!!� Intensely inflammatory
� Need to recognise normal anatomy and variants
� Normal labrum has a variety of shapes
� Always project beyond the glenoid cartilage
� Need to recognise normal anatomy and variants
� Normal labrum has a variety of shapes
� Always project beyond the glenoid cartilage
Whatever the shape – check the position!
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� Chronic Bankart tear
� Reattached (often synovialised) in non-functional position
� High attachment of ligament can simulate Bankart lesion
� Need to carefully follow structures on contiguous images
� Highly variable� Shape� Attachment
� Most variation seen anterosuperiorly� 12 to 3 O’Clock
Blend with cartilage
Extend over cartilage
Sublabralsulcus (recess)
Sublabralforamen
Continuous
YESRecess
V RareCartilage Overlap
YesForamen
Never
� Most labral variation
Common Common Occasional
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� Absent anterosuperior labrum
� Large cord like MGHL
� Attachment of biceps and superior glenoid is highly variable
� Clean edges, < 5mm
� Only one
� Curves smoothly medially
� Not seen in posterior third of superior labrum
Tuite MJ et al. Radiology 2000;215:841
� Careful positioning� Neutral, avoid internal rotation
� Aware of normal anatomy
� Rotator Cuff
� Labrum & LigamentsT2 (fs)
T1 (fs)
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