17/10/2017 Imaging the Knee Alicia M. Yochum RN, DC, DACBR, RMSK Iliotibial Band Syndrome Ligamentous Tears (ACL, PCL, MCL, LCL) Meniscal Tears Cartilage Degeneration Quadriceps/Patellar tendinosis Osteochondral Defect Iliotibial Band Syndrome Friction syndrome Common in runners or cyclists Fluid between ITB and Lateral femoral condyle 1
Ligament Injury Grade 1: Minor Sprain Fluid within the ligament without visualized disrupted fibers Grade 2: Severe Sprain/Partial tear Discontinuous fibers Grade 3: Complete tear Signs of Injury Non visualization of the ligament Fluid in the region of the ligament Displacement of the normal ligament fibers Bone marrow edema Cruciate Ligaments Anterior Cruciate Ligament Origin: Lateral femoral condyle (medial) Insertion: Medial tibial eminence (anterior) Function: Resists anterior translation of tibia Synovial membrane envelope 2 Bundles Anteriomedial: Smaller Tight in flexion Posteriolateral: Larger Tight in extension 2
Normal ACL Lateral ACL PCL Medial 3
ACL PCL Medial Lateral ACL tear: Pivot Shift Kissing Contusions Look for bone marrow edema to suggest injury Lateral Femoral condyle Posterior lateral tibial plateau http://www.radiologyassistant.nl/en/p42764e8fe927e/knee non meniscal pathology.html http://pubs.rsna.org/doi/full/10.1148/radiographics.20.suppl_1.g00oc19s135 Unhappy Triad O Donoguhe ACL tear MCL tear Meniscal Tear Historically been taught as medial Recent literature argues for lateral meniscal tear with acute injury Occurs with valgus load Pivot Shift Common in football and skiing 2 3 1 Pentad Medial Patellofemoral ligament Lateral meniscal Injury 4
Deep Sulcus Sign 1.5 mm Anterior Cruciate Ligament Tear Check ALL Planes! 5
ACL Mucoid Degeneration Celery Stalk appearance NO secondary signs of acute tear Associated ganglion cyst Case courtesy of A.Prof Frank Gaillard, Radiopaedia.org, rid: 3580 Cruciate Ligaments Posterior Cruciate Ligament Origin: Medial femoral condyle (lateral) Insertion: Tibial plateau (anterior) Function: Resists posterior displacement of tibia when knee flexed Thicker and more cordlike Injured in Motor vehicle accident (dashboard injury) Posterior Cruciate Ligament Normal 6
Case courtesy of Radiopaedia.org, rid: 11812 Case courtesy of Dr Chris O'Donnell, Radiopaedia.org, rid: 18243 Collateral Ligaments Medial Collateral Ligament Origin: Superiomedial aspect of the medial femoral condyle Insertion: Medial tibial condyle 2 5cm distal to the tibial plateau Has several layers, the innermost of which is attached to the medial meniscus Function: Resists valgus angulation of Knee 7
Medial Collateral Ligament 8
MCL Sprain Medial Fluid on both sides of the MCL Bone marrow edema!? 9
17/10/2017 Collateral Ligaments Lateral Collateral Ligament Origin: Lateral aspect of the lateral femoral condyle Insertion: Fibular head Function: Resists varus angulation of Knee LCL Normal LCL 10
Lateral/Fibular Collateral Ligament Tear Posterior lateral corner injury LCL, Biceps Femoris, Popliteus (Multiple Ligaments) Meniscal Anatomy Medial C Shaped Has attachments to the Medial Collateral Ligament Lateral O Shaped Roots attach to the tibia and if torn allow extrusion Transverse ligament anteriorly can be confused with a tear Types of Meniscal Tears Horizontal: Type of degenerative tear Radial: traumatic Bucket Handle: surgical case Double PCL sign Double Delta 11
Meniscal injury Grading system Grade I Amorphous area of increased signal that does not reach with an articular surface Corresponds to mucoid degeneration not believed to cause symptoms Grade 2 Band of increased signal with more linear shape Does not communicate with an articular surface Grade 3 Increased signal intensity that reaches the articular surface Meniscal Tears 12
Meniscal Mucoid Degeneration Meniscal Mucoid Degeneration Meniscal Mucoid Degeneration 13
Bucket Handle Tear Bucket Handle Double PCL Double Delta Quadriceps Tendon Injury Superficial layer:rectus femoris Middle layer:vastus medialis, vastus lateralis Deep layer:vastus intermedius 14
Quadriceps Tendinopathy Case courtesy of Dr Maulik S Patel, Radiopaedia.org, rid: 25215 15
Tendon Rupture Osteochondral Defect 16
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Ax PD FS Case Courtesy of UCSD, Dr. Don Resnick Cor T2 FS Cor T2 FS Sag PD 18
The entity previously known as SONK Spontaneous Osteonecrosis of the Knee Demographics Elderly patients, more commonly females Usually no history of trauma Location Usually unilateral Strong predilection for medial compartment Femoral Condyle Etiology debated Previously considered Osteonecrosis Currently considered insufficiency fracture Focal Osteonecrosis Related to microtrauma Prognosis >2.3cm = increased incidence of OA >5cm poor prognosis (Necrotic segment may collapse) Alicia.Yochum@rmcrc.com 19