Lawrence Gulotta Gillian Lieberman, MD October Gillian Lieberman, MD. Shoulder Imaging. Lawrence V. Gulotta, HMS IV 10/16/02

Transcription

1 October 2002 Shoulder Imaging Lawrence V. Gulotta, HMS IV 10/16/02

2 Goals Review Anatomy of the Shoulder -Dynamic Stabilizers -> Rotator Cuff -Static Stabilizers -> Labrum and Capsule Systematic Approach to Reading Shoulder MRI Shoulder Pathology and its Imaging

3 Epidemiology Large range of motion predisposes to injury 4 million Americans seek treatment for shoulder pain each year. Accounts for 1.5 million visits to orthopaedic surgeons annually. Affects all age groups

4 Dynamic Stabilizers Acromion Supraspinatus AC Joint CA Lig Rotator Interval Biceps-Long Head Coracoid Subscapularis Coracobrachialis Biceps- Short Head

5 Dynamic Stabilizers Supraspinatus Scapular Spine Infraspinatus Quadrangular Space Teres Minor Teres Major

6 Static Stabilizers Acromion Biceps- Long Head CA Ligament SGHL Coracoid MGHL Labrum IGHL- Posterior Band IGHL- Anterior Band

7 Approach to Shoulder MRI 1. STIRs -look for edema (high intensity) Infraspinatus Teres Minor

8 Approach to Shoulder MRI 1. STIRs -look for edema (high intensity) Supraspinatus

9 Approach to Shoulder MRI 1. STIRs -look for edema (high intensity) 2. Proton Density-Coronal -Infraspinatus -Teres Minor -Lateral Sloping Acromion -Supraspinatus -Superior/Inferior Labrum -AC Joint

10 Approach to Shoulder MRI 1. STIRs -look for edema (high intensity) 2. Proton Density-Coronal -Infraspinatus -Teres Minor -Lateral Sloping Acromiom -Supraspinatus -Superior/Inferior Labrum -AC Joint

11 Approach to Shoulder MRI 1. STIRs -look for edema (high intensity) 2. Proton Density-Coronal -Infraspinatus -Teres Minor -Lateral Sloping Acromiom -Supraspinatus -Superior/Inferior Labrum -AC Joint

12 Approach to Shoulder MRI 1. STIRs -look for edema (high intensity) 2. Proton Density-Coronal -Infraspinatus -Teres Minor -Lateral Sloping Acromiom -Supraspinatus -Superior/Inferior Labrum -AC Joint 3. Proton Density-Axial -Long Head of Biceps -Subscapularis -Anterior/Posterior Labrum

13 Approach to Shoulder MRI 1. STIRs -look for edema (high intensity) 2. Proton Density-Coronal -Infraspinatus -Teres Minor -Lateral Sloping Acromiom -Supraspinatus -Superior/Inferior Labrum -AC Joint 3. Proton Density-Axial -Long Head of Biceps -Subscapularis -Anterior/Posterior Labrum 4. Proton Density-Sagittal -Inferior Sloping Acromion -Atrophy of RTC muscles

14 Our Patient 83 year old male who complains of pain in his left shoulder for 8 months following a fall on his outstretched arm. -Unable to lift arm over head -Pain wakes him up from sleep at night -PE of left shoulder significant for: -Abduction with a shrug to 45 degrees. -Positive impingement signs -Supraspinatus strength 1/5

15 Our Patient: Plain Films Impingement Series Internal Rotation IR and ER views are used to evaluate for fractures, bone lesions, DJD, and the relationship between humerus and glenoid. ->Humerus rides high in RTC deficient shoulder. External Rotation Axillary Axillary views evaluate for dislocations. Scapular Outlet View Scapular Outlet view is used to assess the space available for supraspinatus Wheeless Online

16 Our Patient This patient s plain films are normal. The next appropriate step in his work-up would be an MRI. MRI is 100% sensitive and 95% specific in the diagnosis of complete tears of the rotator cuff. (Ionnotti et al. JBJS(Am);73(1):17-29)

17 Findings: 1. Hyperintense lesion through full thickness of supraspinatus Our Patient: MRI

18 Findings: Our Patient: MRI 1. Hyperintense lesion through full thickness of supraspinatus 2. Laterally sloping acromion completely occluding supraspinatus outlet

19 Findings: Our Patient: MRI 1. Hyperintense lesion through full thickness of supraspinatus 2. Laterally sloping acromiom completely occluding supraspinatus outlet 3. Retraction of supraspinatus with fatty degeneration

20 Findings: Our Patient: MRI 1. Hyperintense lesion through full thickness of supraspinatus 2. Laterally sloping acromiom completely occluding supraspinatus outlet 3. Retraction of supraspinatus with fatty degeneration 4. Degeneration of supraspinatus on sagittal images

21 Findings: Our Patient: MRI 1. Hyperintense lesion through full thickness of supraspinatus 2. Laterally sloping acromiom completely occluding supraspinatus outlet 3. Retraction of supraspinatus with fatty degeneration 4. Degeneration of supraspinatus on sagital images 5. Absence of long head of biceps in bicipital groove

22 Our Second Patient 34 year old RHD male former minor league baseball pitcher who complains of right shoulder pain for the past 6 months. -Can feel clicking in shoulder when playing catch with his son but no sensation of instability. -PE of right shoulder significant for: -Positive O Brien s test suggestive of a Superior Labral tear from Anterior to Posterior (SLAP). -Negative apprehension tests. -Plain radiographs were unremarkable.

23 Our Second Patient (con t) MRI without intra-articular contrast has a sensitivity anywhere from 60-98% in the diagnosis of SLAP lesions. -Depends on the series and the severity of the tear. MR-Arthrography has an 89% sensitivity and 91% specificity in the diagnosis of SLAP lesions 2. The appropriate imaging study for SLAP tears is controversial -At this institution, it is recommended that labral tears be evaluated by MR-arthrography. 2. Bencardino et al; Radiology; 214(1):267-71

24 Our Second Patient: MR Arthrogram SLAP Lesion Normal Inferior Labrum

25 Summary Rotator Cuff Tears -Older Patients -Pain with Rest -PE c/w Impingement and RTC weakness -Plain films can show high riding humerus and obstructed outlet -MRI diagnostic Labral Tears -Younger Patients -Pain with Activity -PE c/w Labral tear and possibly instability -Plain films usually normal -MR-arthrography diagnostic

26 Acknowledgements Dr. Gillian Lieberman Pamela Lepkowski Dr. Mary Hochman Larry Barbaras