Imaging of shoulder - Dr. Vishal Sankpal

Imaging of shoulder

Imaging of shoulderDr. Vishal Sankpal

AbbreviationsSST supraspinatus IST infraspinatusSSC subscapularisTM teres minorRTC rotator cuffGHL glenohumeral ligamentIGHL inferior glenohumeral ligamentGHLC glenohumeral labral complexPC post contrast

IntroductionThe 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 bodyTo 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 complexligaments and muscle help in stability.

Anatomy

Joints (shoulder complex)

Parts of Synovial JointArticulating bonesSynovial membraneFibrous capsuleIntra-articular structures (like labrum)LigamentsBursaeMuscles

Glenohumeral JointBall and socket synovial jointVery mobileinstability45% of all dislocations !!Joint stability depends on multiple factors (static and dynamic stabilizers)

Bones

Fibrous CapsuleLoose for maximum movementsGaps:Anteriorly: allows communication between synovial membrane and subscapularis bursa.Posteriorly: allows communication with infraspinatus bursa.

Synovial MembraneAttached 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.

Glenoid labrumFibrocartilage similar to knee menisciDeepens the glenoid fossa

Ligaments

Muscles

BursaeSac between two moving surfaces that contains a small amount of lubricating fluidTo reduce friction

Acromioclavicular joint

Diarthrodial joint / Gliding synovial jointThin capsuleAC ligamentsAnterior, posterior, superior, inferiorCoracoacromial ligamentCoracoclavicular ligamentsTrapeziod ligamentConoid ligament

Stability

Static stabilizersglenohumeral ligaments, glenoid labrum and capsule

Dynamic stabilizersPredominantly rotator cuff muscles and biceps (long head)Also scapular stabilizersTrapezius, levator scapulae, serratus anterior, rhomboids

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Radiography

RadiographyInitial 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 spurAxial or anterior oblique views in trauma

AP :Routine view

AP relative to thoraxSuboptimal view of Glenohumeral jointGood view of AC joint

AP View:External Rotation

Greater tuberosity & soft tissues profiled and better visualized

AP View:Internal Rotation

May demonstrate Hill-Sachs lesions

Axillary lateral View

Good view of anterior-posterior relationship of GH joint

Scapular Y Lateral View of the ShoulderShoulder impingement: to evaluate the subacromial space and the supraspinatus outlet

Ultrasonography

USGPreferred initial modality in suspected RTC pathologies> 90 % sensitive and specific for RTC tearsComparable to MRI in evaluation of full thickness rotator cuff tearsBony pathologies not well seen

Advantages: no ionizing radiation, no contrast agent, relatively inexpensive, readily availableDynamic evaluationGuided aspiration / injection possible

Limitations: Less sensitive for detecting partial thickness rotator cuff tearsCannot accurately evaluate the labral-ligamentous complex.

Shoulder USG Protocol(Radiology: Volume 260: Number 1July 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

Step 1 - Biceps brachii tendon, long head

Step 2 - Subscapularis

Step 2 - Subscapularis

Step 3 - Supraspinatus

Step 3 - Supraspinatus

Step 4 - Acromioclavicular jointDynamic evaluation for subacromial impingement

Step 5 - Infraspinatus, teres minor, and posterior labrum

CTSuperior to plain radiographs in evaluation of complex fractures and fracture-dislocations involving the head of the humerusAllows planning of treatment of complex proximal humeral fractures

CT

1) Glenoid2) Humerus3) Deltoid4) Infraspinatus5) Scapula6) Supraspinatus7) Clavicle8) Subscapularis9) Teres minor10) Triceps11) Pec major12) Pec minor13) Biceps (long)14) Biceps (short)15) Teres major16) Latissimus

MRI

MRIHighly accurate for evaluation of rotator cuff pathologiesIndicated 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

MRI Technique

-T1 and T2 FS-Oblique Coronal-T1 and T2 FS-Oblique Sagittal -T2 FS and GRE-Axial

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Normal T1Normal FS T2Normal FS PD

Rotator Cuff (Sagittal)

Infraspinatus;Teres Minor;Subscapularis

Supraspinatus;

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Rotator Cuff (Coronal)

-Primary Plane for Evaluating the Supraspinatus Tendon

-Musculotendinous Junction at 12:00 Position

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Rotator Cuff (Axial Plane)

-Primary Plane for Evaluating Subscapularis

-Infraspinatus Located Posteriorly

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Rotator Cuff (Coronal)

- Infraspinatus- Located Posteriorly - Slopes upward

-Subscapularis- Located Anteriorly- Multi-slip tendon

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Arthrography

Arthrography

PREREQUISITES:Obtain signed consent.

RISKS:Infection, Pain, Hematoma

MATERIALS:22G 3 needle25G 1 needle5 cc syringe with lidocaine for skin anesthesia20 cc syringe with combination of 1% lidocaineOmnipaque 300Gadolinium contrast (if performing MR)

Shoulder MR or CT Arthrography

Place the patient supineTarget the junction of the middle and inferior thirds of humeral head just lateral to the medial cortex of humeral head.Local lignocaine givenFill 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% lidocaineHelical CT should be performed with thinnest slices available, preferably in a single breath hold in both internal and external rotation.

MR arthrographyMost accurate and first line imaging modality for defining: Rotator cuff pathologyLabral/capsule abnormalities in gleno-humeral instabilitySuperior depiction of partial-thickness tears compared to conventional MRI.

Disadvantages : invasive, limited availability and high expense.

CT arthrographyAlternative for assessment of gleno-humeral instability (usually following dislocation) only when MRI is contraindicated or unavailableAllows accurate evaluation of capsule / labral disorders

Disadvantage invasive, radiation

Shoulder Pathologies

PathologiesRotator Cuff

Biceps tendon

Labrum and capsule

Osseous structures

Arthritis

Neural impingement

Tumors

Miscellaneous

Rotator cuff

TendinopathyPartial tearsFull thickness tearsCalcific tendinitisParsonage Turner syndrome

Rotator cuff tendinopathyAlso known as -Rotator cuff tendinosis

Definition collagenous degeneration of rotator cuff tendons, most commonly supraspinatus (SST)

Radiographic findings Acromial remodeling / sclerosisAC joint hypertrophyHumeral head subchondral sclerosis / cysts

MRIT1W thickened heterogeneous tendons with intermediate signal intensityT2W low to intermediate signalFS PD and STIR heterogeneous tendons with increased signal intensityHyperintense effusion (glenohumeral joint)Hyperintense bursitis ( subacromial / subdeltoid )Type III (hooked) acromionMR arthrography no cuff defect identified

HRUSThickened hypoechoicTears directly visibleLess sensitive for partial thickness tearsAdvantage allows dynamic evaluation with pain correlation

Differentials Partial tear T2 (without fat sat) shows diminished / intermediate signal intensity in tendinosis as compared to a hyperintensity of a true cuff tearCalcific tendinitis thickened tendon with decreased signal on all sequencesForm of tendinopathyHyperintense surrounding edema on T2WIIntratendinous cyst Well defined , usually ovalHyperintense cyst on T2WIMagic angle artifact Increased signal at curved portion of tendon55 degrees to external magnetic fieldAffects biceps and SST tendon and labrum

Rotator cuff tearsClinical Trauma (acute / chronic micro-trauma)Adults > 4o with impingementCollagen vascular diseasesPartial more painful than complete tears !!!!

TYPES - Partial supraspinatus most commonTypes bursal surface interstitial (not seen on arthroscopy) articular surface Complete supraspinatus most commonExtends from bursal to articular surface

Partial tears

Radiographic findings Findings associated with impingement and degenerative changes

Acromial spursType III (hooked) acromionHumeral head arthritic changes at greater tuberosityAC degenerative changes

MRI

Incomplete defect in tendon filled with joint fluid +/- granulation tissue

T1WI thickening of RTC tendonsintermediate signalCalcificationshypointense bone impaction (Hill-Sachs) in case of anterior dislocation

T2WI Fluid signal intensity filling an incomplete gap in tendonFluid in subacromial bursaIncreased signal on FS PD (sensitive for partial tears)Retraction and degeneration of tendon edges (bursal or articular)

PC T1 enhancement of the granulation tissue

MR arthrography Contrast may fill the tear if articular surface of the tendon communicates with joint

USG Decreased echogenicity and thinning in affected regionLoss of convexity of tendon / bursa interface in bursal surface tearsCalcific foci in tendons

Differentials RTC tendinopathy Full thickness tear without visible communication closed by granulation tissue / fibrosis / adhesionsIntratendinous cyst can be associated with partial tears Calcific tendinitis hypointense on all sequences

Full thickness tears

Full thickness tears Etiology similar to partial tears

Associated with Hill Sachs deformity (anterior dislocation)Biceps tendinosis / tears / SLAP lesions with micro instability

RadiographyAcromial spursType III (hooked) acromionHumeral head arthritic changes at greater tuberosityAC degenerative changesSuperior humeral head migration

MRI T1WI Thickened indistinct tendonTear edges not delineated on T1Calcifications (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 T2Fluid in subacromial bursaRetraction and degeneration of tendon edgesSometimes associated with fatty atrophy of muscles (fat signal on T1)

Bald spot sign

USGFocal tendon interruptionFluid filed gap (hypoechoic)Loss of convexity of tendon / bursa interfaceTendon retractionUncovered cartilage sign

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)

Rotator interval tears

Rotator interval tearsWhat is rotator interval ??Tunnel through which long head of biceps travels from its origin at the supraglenoid tubercleRotator interval tears tears in the capsule between the supraspinatus and subscapularis tendonsCan be classified as subtype of RTC tears

MRIT1 Thickened rotator intervalBiceps tendinosis and subluxation

T2 Visible tear in rotator intervalAssociated tear of SST may be presentFS PD sag images are useful to detect abnormal fluid extension across rotator interval

MR arthrography Leakage of contrast through the tear in RIIntact SST and SSC

Internal impingement

Internal impingementDefinition - 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)

MRIT1 Thickened posterior SST and anterior IST (tendinosis)Postero-superior labral irregularity (fraying)Tear in postero-superior labrum (can be avulsed) Postero-superior humeral head irregularityT2 Hyperintense signal on articular surface of posterior SST and anterior IST Hyperintense signal (FS PD) in postero-superior humeral head, humeral head chondromalaciaFraying +/- tear of PSGL

Synovitis, labral fraying, sclerosis at posterosuperior glenoid, cystic changes in posterolateral humeral headAxial FS PD

MR arthrography Postero-superior labral fraying / tear demonstrated by contrast outlineABER imaging shows undersurface tearsChondromalacia outlined by contrast

Best diagnostic clue - triad of damage at

Undersurface of RTCPostero-superior labrumHumeral head

Differentials Subacromial impingement (history differs)SLAP without RTC pathology

Rotator cuff calcific tendinitis

Rotator cuff calcific tendinitisCalcium 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

Stages / classification(Moseley)Silent

Mechanical intra bursal or sub bursal rupture Physical restriction of movements

Adhesive peri-arthritis tendinitis bursitis

RadiographyCalcific depositsInternal rotation demonstrates posterior tendons well (IST and TM)Axillary view and scapula Y view helpful

CTBetter localization of calcium depositsDense, granular, well demarcated calcifications

MRIGlobular decreased signal mass (on all pulse sequences) in RTC tendonsOften surrounded by edema / partial tear (hyperintense)No involvement of articular cartilageHydroxyapatite deposits may have exactly same signal as normal cuff tendonsT2*GRE is helpful as calcifications bloom and increase sensitivity

Axial PD

Differentials Degenerative calcification in torn tendon Usually smaller calcificationsIn older age groupDifferent chemical composition

Loose bodies Chondral defects seenArticular OA changes

Osteochondromatosis

Parsonage - Turner syndrome

Parsonage - Turner syndromeIdiopathic denervation of the shoulder musculatureMore than one nerve may be involvedMainly affects the LMN of the brachial plexus and / or individual nerves or nerve fibers

Etiology Immune mediated reaction against nerve fibersTrauma, infection, surgery, vaccination, systemic illness

Pathology Degenerative changes in affected musclesEarly and subacute swollen muscle bellyChronic - fatty atrophy

CTAcute / subacute cases mildly increased bulk of musclesChronic cases fatty density in involved muscles

MRIMRI 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 bulkChronic atrophic musclesNerve distribution pattern +/-

PC T1 muscle belly enhance in early stages

DifferentialsTraumatic neurapraxiaNon specific myositis ( usually nerve pattern not followed)Direct trauma to the muscle belly (history)

PathologiesRotator Cuff

Labrum and capsule

Biceps tendon

Osseous structures

Arthritis

Neural impingement

Tumors

Labrum and capsuleLabral cystAntero-superior variationsAdhesive capsulitisBankartPerthesALPSAGLADHAGLIGLBennett

Labral cyst

Labral cystCyst arising from labral / capsular tear / capsular diverticulumEtiology cyst arising due to break in integrity of joint3-5 % of labral tears associated with labral cystsSlow growing, original tear may healAssociated abnormalities Instability (non healed)SLAP (superior labrum anterior to posterior)Denervation of SST and IST (compression)

MRICommon location adjacent to postero-superior labrum funneled between SST and IST (path of least resistance) T1 Decreased signal intensity cystic massT2 Hyperintense cystic lesionOften multiloculatedArising from / immediately adjacent to the labrum / capsuleDegenerative changes in SST / IST (suprascapular nerve)Labral tearMR arthrogrpahy Cyst filled with contrast

DifferentialsNeoplasmInternal enhancementNot associated with labral / capsular tear

Normal vessel plexus in suprascapular notchCan be enlarged in CHF

Antero-superior labrum variations

Antero-superior labrum variationsCongenital anatomical variationsMay be developmental

Sub-labral foramen Buford complex (BC) Labral types Synovial recesses

Sublabral foramenRelative 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 labrumShould not be confused with SLAP lesionBankarts lesion below the equator (antero-inferior)

Axial FS PD - anterior labrum directly attached to the hyaline cartilage

Buford complexComplete absence of antero-superior labrum +Thick cord-like middle glenohumeral ligament (MGHL) anterior to the anterosuperior glenoid rim

Buford complex

Labral typesVariations in labral attachment patterns

Superior wedge labrumPosterior wedge labrumAnterior wedge labrumMeniscoid labrum

Synovial recessesVisualized on sag images as capsular variations relative to MGHL

Adhesive capsulitis

Adhesive capsulitisFrozen shoulder

Pathology - Inflammation of the inferior shoulder capsule (axillary pouch) causing limited range of motion

May accompany other disorders like impingement (secondary adhesive capsulitis)

Etiology Idiopathic (primary), trauma, infection, surgery, metabolic (diabetes)

RadiographyPlain radiography not usefulArthrography Contracted irregular capsuleDecreased volume +/-Over-injection may leading to capsule rupture may be therapeutic !!! (improved ROM)

MRIT1 Thickened indistinct capsule margins

T2 Thickened capsule (> 3mm on coronal images)Increased signalThickening more conspicuous on FS PD, STIR and T2*GREFS more sensitive for capsular edema and synovitisSagittal images for rotator interval

MR arthrography Capsule enhances diffusely, acutelyRestricted capsular volume

Bankart lesion

Bankart lesionAvulsion of inferior glenohumeral labral complex (IGHLC)

Etiology IGHLC is a weak link among the static stabilizers of young shoulderOccurs after initial anterior dislocation in young ( > 90% cases are < 40 years)

Asociated abnormalities

Bony Bankart osteochondral fracture in some cases

Hill Sachs lesion fracture at posterolateral superior humeral head

Partial / complete RTC tears

Radiography Subglenoid / subcoracoid dislocationGlenoid rim fracture

CTArthrography contrast extending into the labral tear

MRIT1 Hypointense edema / sclerosis at antero-inferior glenoidGlenoid rim fracture (sag and axial more useful)

T2 Labrum torn with hyperintense fluid, within or underlying labrumfracture line at glenoid rimFracture at postero- lateral humeral headThickened 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

Prognosis Recurrent instability (improper healing)

Rx - Conservative with a slingSurgical or arthroscopic repair for repeated dislocations

Perthes lesion

Perthes lesionBankart variant (uncommon 5-10 % of Bankart lesions)

Detached IGHLC with intact scapular periosteum, which is stripped medially

Etio-pathology similar to Bankart lesion

MRIT2 Subtle linear increased signal intensity at the base of usually non-displaced labrum Bankart fractureRedundant hypointense periosteum

STIR provides improved contrast for visualization of medially stripped scapular periosteum

MR arthrography in ABER (arm placed behind the head)

ALPSA lesion

ALPSA lesionAnterior Labro-ligamentous Periosteal Sleeve Avulsion

Components - Anterior IGHLC avulsion from antero-inferior glenoidIntact periosteumMedial displacement and inferior shift of the anterior IGHLC

MRIT2 Medial displacement of IGHLC on axial and coronal images Hyperintense in acute casesHypointense in chronic casesHyperintense edema and hemorrhage in joint capsule and adjacent soft tissues

MR arthrography Medial and inferior displacement of labrumChronic cases with re-synovialisation show minimal displacement

GLAD lesion

GLAD lesionGlenoid Labrum Articular Disruption

Definition - Partial tear of anterior glenoid labrum with adjacent articular cartilage defect

Young physically active patientsPain on IR and adduction

MRIIrregular increased signal intensity on T2 / FS PD within the anterior labrum and adjacent hyaline articular cartilageLabral tear is typically not detachedChondral defect well seen on FS PD (not well seen on T2)MR arthrography Contrast filling the labral tear Contrast may fill the chondral defectABER demonstrates partial labral tears by placing stress on capsular ligamentous attachments

HAGLHumeral 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

Bennett lesionExtra-articular posterior ossification associated with posterior labral injury and posterior cuff pathology

Dystrophic / heterotopic ossification

Throwing athletes (javelin, baseball)

Radiography Mineralization adjacent to posterior glenoidBetter visualized on axillary view

CT arthrography Posterior labral tear

MR Crescent shaped areas of ossification Adjacent to posterior labrumLabral tearT2*GRE show bloomingMR arthrography posterior labral tear

Posterior labral tearReverse Bankart Secondary to posterior dislocationPosterior band of IGHLC weak link among static stabilizers in most shoulders

Radiography and CT Posterior glenoid rim fractureTrough sign reverse Hill Sachs on anterior humerus creating a trough / defectLesser tuberosity avulsion fracture

PathologiesRotator Cuff

Labrum and capsule

Biceps tendon

Osseous structures

Arthritis

Neural impingement

Tumors

Biceps tendon pathologies

Tendinosis

TendinosisDegeneration of long head of biceps

Long head of biceps LHBT originates at supra glenoid tuberclePasses through the antero-superior jointEnters the humeral bicipital groove

Chronic micro-traumaAcute trauma (rare cause)Accompanies RTC disease (especially impingement)Common with subacromial impingement (30-60% association)Biceps tenosynovitis may accompany

Radiography - Sclerosis at the superior aspect of bicipital groove (chronic cases with instability)

USG Thickened hypoechoic tendonTears often directly visibleAllows dynamic evaluation

MRIT1 Thickened intermediate signal intensity tendonSST tendinopathyT2 Thickened (> 5 mm), irregular frayed tendonIncreased signalFS PD and PD more sensitive for tendinosisT2 more sensitive for fraying / tearsSST tendinopathy MR arthrography thickened filling defect (enlarged tendon)

Biceps tendon tear

Biceps tendon tearTendinosis predisposesAssociated with SST tearDistal tendon edge may retract into upper arm

CT arthrography Bicipital groove filled with contrastAbsence of normal filling defect

MRI Irregular stump at superior aspect of jointPartial or complete hyperintense fluid gap in the tendon (T2) Synovitis (PD)

Biceps tendinitis grading for tenodesis (repair)

Reversible tendon change < 25 % partial tear (width) normal bicipital groove location normal size

Irreversible tendon change > 25 % partial tear subluxation disruption of bicipital groove osseous / ligamentous anatomy

SLAP lesions

SLAP lesionsSuperior 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 IComplete anterior to posterior extension in SLAP II - IV

MRI (T2)SLAP I Intermediate to hyperintense labral degeneration without labral tearRepresents intra substance degenerationCan 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

SLAP ISLAP II

SLAP III

SLAP IV

Rx Conservative NSAIDsPT

Surgical Type I debridementType II stabilize, bioabsorbable tack (sutures)Type III debridementType IV suturing of biceps , reattachment of labrum

Biceps tendon dislocation

Biceps tendon dislocationBiceps 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 bicepsShallow bicipital groove predisposes

MRIT1 Increased signal intensity fat fills the bicipital groove

T2 Tendon not in grooveMostly 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

USGEmpty grooveDisplaced 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)

PathologiesRotator Cuff

Labrum and capsule

Biceps tendon

Osseous structures

Arthritis

Neural impingement

Tumors

Osseous structures

Osseous structuresSubacromial impingementOs acromialeAVNDislocationOsteochondral injuries

Subacromial impingement

Subacromial impingementPhysical impingement with repeated micro trauma

Etiology Primary extrinsic - Subacromial spur, AC OAType III (hooked) acromionLateral down sloping of anterior acromionOs acromialeSecondary extrinsic no osseous abnormality of coracoacromial arch

Rx conservative, Acromioplasty

Acromial TypesType I

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Acromial Types

Type II

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Acromial Types

Type III

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Acromial TypesType IV

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MRIHooked acromion on sagittal images with decreased subacromial outletLateral down sloping seen on coronal imagesSubacromial space < 7 mm considered increased riskChanges of RTC tendinopathyPartial tears may be seenBursitisThickened coracoacromial ligament

Coracoid Impingement

-Normal Coracohumeral Distance is 11 mm

-Narrowed C-H Distance can Impinge on Subscapularis

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Os acromiale

Os acromialeUnfused acromial ossification center Normally fuses by 25-30 yearsMature bone with synchondrosis between os and acromion+/- mobile distal acromionCan cause impingement

Rx conservative, preacromian excison, stabilization

TypesBasi-meta (type C)Meta-meso (type A)Meso-pre (type B most common)

MRIAge > 25-30 yearsUnfused bony fragmentCorticated structure with medullary fat in it (hyperintense)Hypointense sclerosis at its marginsPseudo double AC joint (axial and cor)T2*GRE unfused ossification demarcation (hyperintense)

Double AC joint sign

Avascular Necrosis

AVNAVN / osteonecrosis It is ischemic death of cellular elements of bone and marrowEtiology steroids, alcohol, smoking, trauma, collagen vascular diseases, arteritis, storage disorders (Gauchers), idiopathic2nd most common (after femoral head)

RadiographyArc like subchondral fracture (crescent sign) Articular collapse (step sign)FragmentationSubchondral lytic sclerotic areasSubchondral cystsDeformed humeral headSecondary degenerative changes

AVN

ClassDescriptionINormal (can be seen on MRI)IIsclerosis in superior central portion of the headIIIcrescent sign - caused by subchondral bone collapse; may have mild flatteningIVsignificant collapse of humeral articular surface.Vdegenerative joint disease.

Cruess X-ray Classification of AVN Humeral Head

MRISupero-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 edemaSubchondral collapse and cysts

FS PD more sensitive for ischemic edema in acute cases

PC T1 the granulation component of double line sign may enhanceMR arthrography contrast extend into the necrotic bone

Best diagnostic clue Supero-medial involvement Double line sign on T2W

Osteochondral injuries

Osteochondral injuriesDefinition - 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

MRIT1 Subchondral sclerosis and edema

T2, FS PD and STIR Increased signal in articular cartilageUnderlying 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

Outerbridge classification of articular cartilage injuriesGrade 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

PathologiesRotator Cuff

Labrum and capsule

Biceps tendon

Osseous structures

Arthritis

Neural impingement

Tumors

Arthritis

OsteoarthritisGlenohumeral joint Acromio-clavicular joint (AVC)

Relatively uncommon compared to impingementOlder patients Younger patients (post trauma / post surgery)

Radiography Joint space narrowingOsteophytesSubchondral cysts and sclerosis

MRISubchondral cytsOsteophytes (marrow signal extends into it)Generalized thinning of hyaline cartilage, with occasional focal defectsSynovitisLoose bodiesPosterior glenoid wear leads to increased retroversion of glenoidPC T1 synovial enhancement in synovitis

Rheumatoid arthritisSynovium articular cartilage subchondral boneMarginal erosions (more at greater tuberosity)Bilateral symmetrical involvementDiffuse synovial thickeningJoint effusionBone erosionsLoss of joint space not prominentMild superior migration of humeral head (RTC rupture) decreased space between HH and acromionClavicular erosions predominate at AC jointTapered and resorbed distal clavicle (chronic cases)

PathologiesRotator Cuff

Labrum and capsule

Biceps tendon

Osseous structures

Arthritis

Neural impingement

Tumors

Neural impingement

Quadrilateral space syndrome

Entrapment neuropathy (compression) of axillary nerve in quadrilateral space

Boundaries Superiorly teres majorInferiorly teres minorMedially long head of tricepsLaterally humerus

Best diagnostic clue Increased signal in teres minor and deltoid on FS PD or STIR (denervation)Streaky decreased signal intensity (fibrosis)

Suprascapular / Spinoglenoid notchImpingement of suprascapular nerve

Location - SSN at superior glenoidSGN at posterior glenoid

Best diagnostic clue Increased signal in SST and IST on FS PD or STIR (denervation)Streaky decreased signal intensity (fibrosis)

Miscellaneous PathologiesDislocationsFracturesTumorsAC separation

DislocationTypesShoulder 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 %

Anterior Dislocation

Anterior Dislocation

Posterior dislocation

APScapular Y viewAxillary view

Luxatio erecta

TumorsProximal humerus Simple bone cystAneurysmal bone cystGiant Cell Tumor of BoneOsteosarcoma (common)Enchondroma (relatively common)Periosteal chondroma (just proximal to insertion of deltoid)Osteochondroma ChondroblastomaChondromyxoid fibromaMetastases

Scapula Osteochondroma chondrosarcoma: affects the shoulder girdle

Role of interventional radiologyUS and fluoroscopy guided intra-articular and bursal infiltration (steroids, other drugs) Percutaneous needle removal of calcific depositsCapsular 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

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

Thank you.