MRI of the Shoulder:

Labrum

Donald J. Flemming, M.D.

Radiology Department

Penn State Hershey Medical Center

Glenohumeral Instability

• Acute Traumatic Instability

– cartilaginous labrum

– glenohumeral ligaments/ capsule

• Multidirectional instability

– atraumatic

• Developmental

– humeral and glenoid version

– glenoid hypoplasia or humeral dysplasia

Glenohumeral Instability

• Rotator Cuff Dysfunction

– long head biceps tendon

• Scapulothoracic Dysfunction

– serratus anterior

– long thoracic nerve palsy

Glenoid Labrum

• Fibrocartilaginous ring

• Deepens glenoid

• Attachment for capsule

• Superior meniscal configuration

– Long head biceps attachment

• Variable morphology

Glenoid Labrum

Radiologic Evaluation

• Plain radiographs

– Hill-Sachs and bony Bankart

• CT arthrography

• MR

– Noncontrast

– Direct MR arthrography

– Indirect Arthrography

MR Technique

• Need dedicated shoulder coil

• Neutral to external rotation

– Tightens capsule

– Tightens long head biceps tendon

• ABER Position

– Tightens anterior inferior capsule

– Axial oblique

• Axial, Coronal oblique, Sagittal oblique

MR Technique- ABER

Anterior/Inferior

Noncontrast MR

• Noncontrast

– Fat-saturated FSE Proton

– GRE

– T2 (SE or FS)

• Inexpensive/ Little risk

• Poor sensitivity

Noncontrast MRI Accuracy

Labral Pathology

Sensitivity Specificity

Ianotti 88% 93%

Garneau 66.7% 77.8%

Tuite 50% 90%

Legan 95% 86%

Flemming* 0% 0%

* Unpublished data

Indications for Arthrography

• History of instability

• Concern for labral pathology

• Any patient < 35(40) years?

• Direct vs Indirect Arthrography

Direct MR Arthrography

• Improves diagnostic accuracy

• Increases cost

• Requires access to fluoroscopy

• Decreased schedule flexibility

• Increases physician time

• It hurts

Indirect MR Arthrography

• Increases diagnostic accuracy

• Relatively inexpensive

• Technologist can perform exam

• Lack of capsular distension

• Anaphylaxis

• Requires fat saturation

• Enhancement may mimic pathology

Technique

• Inject 15 minutes prior to exam

– 0.1 mmole/kg dose

• Exercise for 10 minutes after injection

• Synovial membrane permeable to

gadolinium

Normal Labrum

• Triangular focus of low signal

• Capsular insertion

– Variable anterior – labrum to neck of glenoid

– Posterior – labrum – less variability

• Glenohumeral ligaments

Normal Labrum

Labral Clock

Shoulder Arthroscopy

• Posterior Portal

– Through Infraspinatus

– Optimum look at anterior-inferior glenoid

– Poor look at posterior/inferior

• Requires experience

• Not a perfect “Gold Standard”

Shoulder Arthroscopy

Humerus

Glenoid

Labrum

Normal Labrum

• Normal variants

• Sublabral foramen

• Buford complex

Sublabral Foramen

Ant/Sup 12:00 – 3:00

No Man’s Land

Sublabral Foramen

No Man’s Land

Buford Complex

• Absent superior

labrum

• Thick middle

glenohumeral ligament

Capsulolabral “Tear”

• Bankart

• Perthes

• ALPSA

• GLAD

• SLAP

• Bennett

• HAGL

• BHAGL

Labral “Tear”

• Antero-inferior most common

– Axial

– Remember to look at coronals

• Superior (SLAP) - not uncommon

• Posterior/inferior most difficult

• Look for second tear 1800

Labral Pathology

• Contrast/signal under labrum

• Abnormal morphology

• Perilabral cyst

• Pitfalls

– Normal variants

– Sublabral foramen

Bankart

Bankart

Bankart

Intralabral Signal

Abnormal Labrum/ Capsule

Associated Findings

• Hill-Sachs Defect

– Posterior humeral head

– First axial cuts (above level of coracoid)

– Seen on internal rotation

– Significant - >30% of articular surface

• Peri-labral cyst

– “100%” association with tears

– Usually chronic/degenerative tears

Hill-Sachs

Perilabral Cyst

Perthes

• Detached labrum with

periosteum intact

• May be missed at MR

without ABER

Perthes

ALPSA

• Anterior Labral Periosteal Sleeve Avulsion

• Periosteal sleeve rolls down on glenoid neck

• May be missed at arthroscopy

ALPSA

GLAD

• Glenoid Labral Articular Disruption

• Hyaline cartilage injury +/- Bankart

Bennett

• Reverse Perthes with ossification

Posterior Labral Tear

• Common in weightlifters

• Extension from superior labral tear

• Retroverted glenoid

• Perilabral cysts

• Easy for arthroscopist to miss

– Look from anterior portal

Posterior Labral Tear

HAGL/BHAGL

• Humeral Avulsion Glenohumeral Ligament

– Add “B” if bony fragment avulsed

• Rare injury

• Easy to miss on arthroscopy and MR

HAGL

HAGL

Superior Labral Anterior to

Posterior

• Type I - fraying

• Type II - detached

• Type III – bucket-handle

• Type IV – extension into biceps

SLAP Tears

• External rotation important

• Type I and II most common

– Differentiate from sublabral foramen

– Difficult to differentiate I from II

– Look for branching signal

• ↑ Signal on T2W is high PPV

• Look for anterior/posterior extension

• Type III and IV – Look for Bankart

Normal Superior Labrum

Type II

SLAP with Extension

Hyaline Cartilage Defects

• 3D volume SPGR with contrast aids

detection

Radiology Report

• Tear – describe location by clock face

– Anterior – 12:00 to 6:00

• Remember equator low

• Look for second labral lesion –1800 away

• Look for hyaline cartilage defect

• Look for rotator cuff tear

• CORRELATE!!!!

Thanks!!