膝关节韧带扭伤的影像学诊断

Vinh Chung Gillian Lieberman, MD Sprained Ligaments of the Knee Vinh Chung, Harvard Medical School Year III Gillian Lieberman, MD July 2001 2 Vinh Chung Gillian Lieberman, MD Agenda • Introduction • Diagnostic Procedures • MRI Images • Our Patient • Summary 3 Vinh Chung Gillian Lieberman, MD Introduction The knee is the most commonly injured joint • Most common orthopedic problem in the ED with 1.3m ED cases per year • Over 50,000 knee injuries require operations in the U.S. each year • Knees are the most common joints examined by MRI • Injuries continue to increase due to sports activities Roberts, DM. Emergency department evaluation and treatment of knee and leg injuries. Emerg Med Clin North Am. 2000 Feb; 18(1): 67-84, v-vi. Rosen, Peter. Emergency Medicine: Concepts and Clinical Practice, 4th ed., 1998 Mosby-Year Book, Inc. Tandeter, Howard. Acute Knee Injuries: Use of Decision Rules for Selective Radiograph Ordering. American Family Physican. December, 1999. Vol. 60: 9. 4 Vinh Chung Gillian Lieberman, MD Ligament Anatomy Netter, Frank. Atlas of Human Anatomy. Second Edition. Novartis: New Jersey. 1997. P. 475. 5 Vinh Chung Gillian Lieberman, MD Anterior Cruciate Ligament vs. Posterior Cruciate Ligament Ligament ACL PCL Size Smaller Larger Location Anterior tibia to lateral condyle Posterior tibia to medial condyle Function Prevent hyperextension and posterior displacement of femur Prevent hyperflexion and anterior displacement of femur 6 Vinh Chung Gillian Lieberman, MD Ligament Injuries Ligament Force Cause Frequency Anterior Cruciate Lateral w/ Knee Extended Sports 60% Posterior Cruciate Frontal w/ Knee Flexed MVA 3-10% Lateral Collateral Medial Rare Medial Collateral Lateral Common Southmayd, William. Sports Health: The Complete Book of Athletic Injuries. Quick Fox: New York. 1981. P. 255-8. Rosen, Peter. Emergency Medicine: Concepts and Clinical Practice, 4th ed., 1998. Mosby-Year Book, Inc. 7 Vinh Chung Gillian Lieberman, MD Meniscus Anatomy • 52% of injuries occur with ACL tears • Failure to repair damage may speed up articular degeneration Rosen, Peter. Emergency Medicine: Concepts and Clinical Practice, 4th ed., 1998. Mosby-Year Book, Inc. Netter, Frank. Atlas of Human Anatomy. Second Edition. Novartis: New Jersey. 1997. P. 474 8 Vinh Chung Gillian Lieberman, MD O’Donoghue Triad 1959 Description • Anterior Cruciate Ligament • Medial Collateral Ligament • Medial Meniscus Arthroscopy & MRI • Anterior Cruciate Ligament • Medial Collateral Ligament • Lateral Meniscus Southmayd, William. Sports Health: The Complete Book of Athletic Injuries. Quick Fox: New York. 1981. P. 248 Adalberth, T. Magnetic Resonance Imaging, scintigraphy, and arthroscopic evaluation of traumatic hemarthrosis of the knee. Am J Sports Med - 1997 Mar-Apr; 25(2): 231-7 9 Vinh Chung Gillian Lieberman, MD Treatment • RICE: Rest, Ice, Compression, Elevation • Surgery Severity Treatment Duration Grade I RICE 5 – 14 days Grade II RICE 14 – 30 days Grade III RICE / Surgery Months 10 Vinh Chung Gillian Lieberman, MD Diagnostic Algorithm History / Physical Exam Suspect Arterial Damage No Diagnosis Diagnosis Arteriogram Plain Films MRI / Arthroscopy Grade III Grade I or II Treatment Fracture No Fracture CT Pain Ultrasound RICE Diagnosis / Treatment 11 Vinh Chung Gillian Lieberman, MD History and Physical Exam Advantages • Cheap • Non-invasive • Can identify most knee joint lesions • 90% sensitive in detecting ACL injuries Disadvantages • 58% accuracy compared with arthroscopy • Very difficult to diagnose: chondral fractures, loose bodies, and fibrotic fat pads • 38-95% accurate in diagnosing ACL injuries Strobel, Michael. Diagnostic Evaluation of the Knee. Springer-Verlag. 1990. Rosen, Peter. Emergency Medicine: Concepts and Clinical Practice, 4th ed., 1998. Mosby-Year Book, Inc. Tandeter, Howard. Acute Knee Injuries: Use of Decision Rules for Selective Radiograph Ordering. American Family Physican. December, 1999. Vol. 60: 9. 12 Vinh Chung Gillian Lieberman, MD Plain Films Advantages • Cheap • Non-invasive • Rules out fractures and foreign bodies Disadvantages • Overly used: 85% of knee injuries seen in ED get radiographs, but only 6- 12% yield fractures • Cannot image meniscus or ligament Roberts, DM. Emergency department evaluation and treatment of knee and leg injuries. Emerg Med Clin North Am. 2000 Feb; 18(1): 67-84, v-vi. Tandeter, Howard. Acute Knee Injuries: Use of Decision Rules for Selective Radiograph Ordering. American Family Physican. December, 1999. Vol. 60: 9. 13 Vinh Chung Gillian Lieberman, MD Plain Film – ACL Avulsion Bony ligament avulsion apparent at tibial intercondyle eminence Strobel, Michael. Diagnostic Evaluation of the Knee. Springer-Verlag. 1990. 14 Vinh Chung Gillian Lieberman, MD CT Athrogram Advantages • Excellent for fractures • Good for ligament and meniscal tears • Used if MRI contraindication Disadvantages • Not as good as MRI • May be painful Strobel, Michael. Diagnostic Evaluation of the Knee. Springer-Verlag. 1990. Intact ACL Torn ACL 15 Vinh Chung Gillian Lieberman, MD Arthroscopy Advantages • 84-97% accuracy in diagnosing knee pathology • Excellent for treatment • Simultaneous therapy through ligament debridement or reconstruction Disadvantages • Invasive • Cannot see posterior meniscal tear • Difficult to see PCL • Therapeutically, the most commonly performed orthopedic surgical procedure • Diagnostically, the gold standard for intra-articular pathology of the knee, but has been replaced by MRI Rosen, Peter. Emergency Medicine: Concepts and Clinical Practice, 4th ed., 1998. Mosby-Year Book, Inc. 16 Vinh Chung Gillian Lieberman, MD MRI Advantages • No radiation • Non-invasive • Highly sensitive and specific for diagnosing ligament and meniscal lesions • Aid for pre-operative planning • Can preclude unnecessary arthroscopy Disadvantages • Expensive, $600-$1,200 Rosen, Peter. Emergency Medicine: Concepts and Clinical Practice, 4th ed., 1998. Mosby-Year Book, Inc. Gray, Scott. Imaging of the Knee. Current Status. Orthopedic Clinics of North America. October 1997. Volume 28: 4. 17 Vinh Chung Gillian Lieberman, MD MRI Knee Coil • Knee coils eliminate image distortions • Patient is supine, hip fully extended, and knee slightly flexed • Complete exam takes 20 minutes Strobel, Michael. Diagnostic Evaluation of the Knee. Springer-Verlag. 1990. 18 Vinh Chung Gillian Lieberman, MD Normal ACL and PCL ACL PCL • Visualized as linear low signal ligament strand (blue arrows) • Less homogeneous than PCL • Parallels roof of intercondylar notch (yellow arrows) Gray, Scott. Imaging of the Knee. Current Status. Orthopedic Clinics of North America. October 1997. Volume 28: 4. Diagnostic Evaluation of the Knee. Springer-Verlag. 1990. • Uniformly low in signal intensity • Curves superiorly and anteriorly from the tibia to femur 19 Vinh Chung Gillian Lieberman, MD Complete ACL Tear • Poorly defined, mixed signal intensity at location where ACL should be. This is due to blood and edema • High intensity (F) is joint effusion Gray, Scott. Imaging of the Knee. Current Status. Orthopedic Clinics of North America. October 1997. Volume 28: 4. 20 Vinh Chung Gillian Lieberman, MD Acute PCL Tear • High signal intensity wavy fibrids where PCL should be located. This represents hemorrhage and edema Gray, Scott. Imaging of the Knee. Current Status. Orthopedic Clinics of North America. October 1997. Volume 28: 4. 21 Vinh Chung Gillian Lieberman, MD Normal Menisci Proton density-weighted sagittal images of two C-shaped menisci with the curves extending peripherally Lateral meniscus peripherally Lateral meniscus slightly more centrally resembles a bow-tie Lateral meniscus centrally through the two horns shows two triangles Medial meniscus centrally through horns demonstrates two triangles Thornton, Dean and David A. Rubin. Magnetic Resonance Imaging of the Knee Menisci. Seminars in Roentgenology. Volume: 35:3. July 2000. 22 Vinh Chung Gillian Lieberman, MD Meniscal Tear High signal intensity in posterior horn of medial meniscus extending to the surface indicates clinically significant tear Gray, Scott. Imaging of the Knee. Current Status. Orthopedic Clinics of North America. October 1997. Volume 28: 4. 23 Vinh Chung Gillian Lieberman, MD Our Patient • 46 year-old white male with a basketball injury of left knee • Suggests meniscus tear • Negative for fractures and bony avulsions HPI: PE: Plain Films: An MRI is indicated 24 Vinh Chung Gillian Lieberman, MD Diagnostic Algorithm History / Physical Exam Suspect Arterial Damage No Diagnosis Diagnosis Arteriogram Plain Films MRI Grade III Grade I or II Treatment Fracture No Fracture CT Pain Ultrasound RICE Diagnosis / Treatment 25 Vinh Chung Gillian Lieberman, MD Our Patient: Normal Menisci Menisci are normal in signal intensity and morphology in both lateral and medial compartment. Cartilage is preserved 26 Vinh Chung Gillian Lieberman, MD Our Patient: Bone Contusions In the lateral compartment, bony contusions involving lateral femoral condyle and proximal tibia 27 Vinh Chung Gillian Lieberman, MD Our Patient: ACL Tear Increased signal intensity, wavy fibrids where ACL should be. All of these signs suggest complete ACL tear. 28 Vinh Chung Gillian Lieberman, MD Our Patient: Normal PCL PCL is intact and normal in signal intensity. 29 Vinh Chung Gillian Lieberman, MD Our Patient: Medial Collateral Ligament: Grade II Sprain There is increased signal intensity surrounding the medial collateral ligament. MCL is partially torn. 30 Vinh Chung Gillian Lieberman, MD Summary of MRI Findings on our patient • Mensical tear • Complete ACL tear • Bone contusions • Medial collateral ligament, grade II sprain Ruled Out: Ruled In: 31 Vinh Chung Gillian Lieberman, MD Diagnostic Procedure Comparison HPI / PE Plain Film CT US ART MRI Accuracy: Risks: Costs: 32 Vinh Chung Gillian Lieberman, MD Summary • Knee injuries, especially ligament tears, are very common • History and physical examination are valuable, but sometimes insufficient to diagnose ligament tears • MRI is the superior diagnostic tool for ligament injuries of the knees 33 Vinh Chung Gillian Lieberman, MD References • Adalberth, T. Magnetic Resonance Imaging, scintigraphy, and arthroscopic evaluation of traumatic hemarthrosis of the knee. Am J Sports Med - 1997 Mar-Apr; 25(2): 231-7 • Gray, Scott. Imaging of the Knee. Current Status. Orthopedic Clinics of North America. October 1997. Volume 28: 4. • Netter, Frank. Atlas of Human Anatomy. Second Edition. Novartis: New Jersey. 1997. • Roberts, DM. Emergency department evaluation and treatment of knee and leg injuries. Emerg Med Clin North Am. 2000 Feb; 18(1): 67-84, v-vi. • Rosen, Peter. Emergency Medicine: Concepts and Clinical Practice, 4th ed., 1998 Mosby-Year Book, Inc. • Strobel, Michael. Diagnostic Evaluation of the Knee. Springer-Verlag. 1990. • Tandeter, Howard. Acute Knee Injuries: Use of Decision Rules for Selective Radiograph Ordering. American Family Physican. December, 1999. Vol. 60: 9. • Thornton, Dean and David A. Rubin. Magnetic Resonance Imaging of the Knee Menisci. Seminars in Roentgenology. Volume: 35:3. July 2000. Vinh Chung Gillian Lieberman, MD 34 Vinh Chung Gillian Lieberman, MD Acknowledgements Larry Barbaras Cara Lyn D’amour Daniel Lim Daniel Saurborn Leisle Chung Sprained Ligaments of the Knee Agenda Introduction Ligament Anatomy Anterior Cruciate Ligament� vs. �Posterior Cruciate Ligament Ligament Injuries Meniscus Anatomy O’Donoghue Triad Treatment Diagnostic Algorithm History and Physical Exam Plain Films Plain Film – ACL Avulsion CT Athrogram Arthroscopy MRI MRI Knee Coil Normal ACL and PCL Complete ACL Tear Acute PCL Tear Normal Menisci Meniscal Tear Our Patient Diagnostic Algorithm Our Patient:�Normal Menisci Our Patient:�Bone Contusions Our Patient:�ACL Tear Our Patient:�Normal PCL Our Patient:�Medial Collateral Ligament: Grade II Sprain Summary of MRI Findings �on our patient Diagnostic Procedure Comparison Summary Slide Number 33 Acknowledgements