This document provides information on MRI findings related to knee trauma. It describes common mechanisms of injury for the ACL, PCL, and menisci. It outlines primary and secondary MRI signs of ACL tears. It also details grading systems for ACL, meniscal, and chondromalacia injuries. Finally, it discusses characteristic bone bruise patterns associated with injuries like pivot shifts, dashboard impacts, hyperextensions, clips, and lateral patellar dislocations.
MRI imaging of knee joint -- from radiological anatomy to pathology. inspired from my dear professor Mamdouh Mahfouz, professor of radio diagnosis - Cairo university.
MRI imaging of knee joint -- from radiological anatomy to pathology. inspired from my dear professor Mamdouh Mahfouz, professor of radio diagnosis - Cairo university.
about basics of cartilage imaging.
how does normal cartilage look , how does diseased cartilage look.
what are advanced techniques in cartilage imaging
Anatomy and imaging of wrist joint (MRI AND XRAY)Kajal Jha
Anatomy and imaging of wrist joint (xray and MRI).
this ppt was made as the class presentation by Kajal Jha as the part of the course of BSC MIT at BPKIHS,Dharan . It covers the part of syllabus of third year of BSC MIT of this institution.
about basics of cartilage imaging.
how does normal cartilage look , how does diseased cartilage look.
what are advanced techniques in cartilage imaging
Anatomy and imaging of wrist joint (MRI AND XRAY)Kajal Jha
Anatomy and imaging of wrist joint (xray and MRI).
this ppt was made as the class presentation by Kajal Jha as the part of the course of BSC MIT at BPKIHS,Dharan . It covers the part of syllabus of third year of BSC MIT of this institution.
This presentation is the first series of the MR imaging of Knee.
In this presentation MRI anatomy has been discussed. As we all know good knowledge of medical imaging three dimensional anatomy is key for good reporting.
Hope we all get benifitted.
Suggestions are most welcome
After completion of this session, students should be able to discuss, identify, and describe:
The anatomical factors predisposing to the etiology of a fracture or dislocation.
The anatomy of displacement or deformity.
Imaging anatomy features and how to differentiate from epiphyseal lines.
Anatomy related to correct relocation and alignment.
Anatomical complications of a fracture or dislocation.
Social networks in anatomy education workable modelsAkram Jaffar
Clarify the evolving role of social media as an instructional tool. Identify the most popular social media networks. Consider challenges faced by educators using social media. Relate the role social media can play in student centered and blended learning. Provide live examples.
The Stone Clinic is a sports medicine clinic in San Francisco, California, offering orthopaedic surgery and medical care, physical therapy and rehabilitation, and radiology imaging services. The Stone Clinic was founded by Kevin R. Stone, M.D., an orthopaedic surgeon, combining himself with a team of nurses, physical therapists, imaging specialists, and patient coordinators, in 1988 to focus on caring for injured athletes and people experiencing arthritis pain.
The Stone Clinic is founded on the goal of rehabilitating all patients to an operating level higher than before they were injured. The Stone Clinic specializes in sports medicine and injury treatment of knee, shoulder, and ankle joints. Stone has lectured and is recognized internationally as an authority on cartilage and meniscal growth, replacement, and repair. Stone and the Stone Clinic are known for the development of the paste grafting surgical technique in 1991, combined with meniscus replacement, which are biologic joint replacement procedures for the regeneration of the knee joint. Surgical procedures were subjected to rigorous outcomes analysis with the results reported in peer reviewed journals. The surgical techniques have been taught to surgeons in the US and worldwide, through lectures and videos.
Nursing students, medical students, residents, fellows, and other physicians from various institutions around the world, rotate through The Stone Clinic and mentor with Stone. The Stone Clinic hosts the annual Meniscus Transplantation Study Group Meeting as well as the annual Professional Women Athlete's Career Conference.
Appendicular trauma refers to injuries or damage sustained to the appendicular skeleton, which includes the bones of the upper and lower extremities (arms and legs) as well as the pelvis. These injuries can result from various causes such as accidents, falls, sports-related incidents, or direct blows.
micro teaching on communication m.sc nursing.pdfAnurag Sharma
Microteaching is a unique model of practice teaching. It is a viable instrument for the. desired change in the teaching behavior or the behavior potential which, in specified types of real. classroom situations, tends to facilitate the achievement of specified types of objectives.
Title: Sense of Smell
Presenter: Dr. Faiza, Assistant Professor of Physiology
Qualifications:
MBBS (Best Graduate, AIMC Lahore)
FCPS Physiology
ICMT, CHPE, DHPE (STMU)
MPH (GC University, Faisalabad)
MBA (Virtual University of Pakistan)
Learning Objectives:
Describe the primary categories of smells and the concept of odor blindness.
Explain the structure and location of the olfactory membrane and mucosa, including the types and roles of cells involved in olfaction.
Describe the pathway and mechanisms of olfactory signal transmission from the olfactory receptors to the brain.
Illustrate the biochemical cascade triggered by odorant binding to olfactory receptors, including the role of G-proteins and second messengers in generating an action potential.
Identify different types of olfactory disorders such as anosmia, hyposmia, hyperosmia, and dysosmia, including their potential causes.
Key Topics:
Olfactory Genes:
3% of the human genome accounts for olfactory genes.
400 genes for odorant receptors.
Olfactory Membrane:
Located in the superior part of the nasal cavity.
Medially: Folds downward along the superior septum.
Laterally: Folds over the superior turbinate and upper surface of the middle turbinate.
Total surface area: 5-10 square centimeters.
Olfactory Mucosa:
Olfactory Cells: Bipolar nerve cells derived from the CNS (100 million), with 4-25 olfactory cilia per cell.
Sustentacular Cells: Produce mucus and maintain ionic and molecular environment.
Basal Cells: Replace worn-out olfactory cells with an average lifespan of 1-2 months.
Bowman’s Gland: Secretes mucus.
Stimulation of Olfactory Cells:
Odorant dissolves in mucus and attaches to receptors on olfactory cilia.
Involves a cascade effect through G-proteins and second messengers, leading to depolarization and action potential generation in the olfactory nerve.
Quality of a Good Odorant:
Small (3-20 Carbon atoms), volatile, water-soluble, and lipid-soluble.
Facilitated by odorant-binding proteins in mucus.
Membrane Potential and Action Potential:
Resting membrane potential: -55mV.
Action potential frequency in the olfactory nerve increases with odorant strength.
Adaptation Towards the Sense of Smell:
Rapid adaptation within the first second, with further slow adaptation.
Psychological adaptation greater than receptor adaptation, involving feedback inhibition from the central nervous system.
Primary Sensations of Smell:
Camphoraceous, Musky, Floral, Pepperminty, Ethereal, Pungent, Putrid.
Odor Detection Threshold:
Examples: Hydrogen sulfide (0.0005 ppm), Methyl-mercaptan (0.002 ppm).
Some toxic substances are odorless at lethal concentrations.
Characteristics of Smell:
Odor blindness for single substances due to lack of appropriate receptor protein.
Behavioral and emotional influences of smell.
Transmission of Olfactory Signals:
From olfactory cells to glomeruli in the olfactory bulb, involving lateral inhibition.
Primitive, less old, and new olfactory systems with different path
Couples presenting to the infertility clinic- Do they really have infertility...Sujoy Dasgupta
Dr Sujoy Dasgupta presented the study on "Couples presenting to the infertility clinic- Do they really have infertility? – The unexplored stories of non-consummation" in the 13th Congress of the Asia Pacific Initiative on Reproduction (ASPIRE 2024) at Manila on 24 May, 2024.
Tom Selleck Health: A Comprehensive Look at the Iconic Actor’s Wellness Journeygreendigital
Tom Selleck, an enduring figure in Hollywood. has captivated audiences for decades with his rugged charm, iconic moustache. and memorable roles in television and film. From his breakout role as Thomas Magnum in Magnum P.I. to his current portrayal of Frank Reagan in Blue Bloods. Selleck's career has spanned over 50 years. But beyond his professional achievements. fans have often been curious about Tom Selleck Health. especially as he has aged in the public eye.
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Introduction
Many have been interested in Tom Selleck health. not only because of his enduring presence on screen but also because of the challenges. and lifestyle choices he has faced and made over the years. This article delves into the various aspects of Tom Selleck health. exploring his fitness regimen, diet, mental health. and the challenges he has encountered as he ages. We'll look at how he maintains his well-being. the health issues he has faced, and his approach to ageing .
Early Life and Career
Childhood and Athletic Beginnings
Tom Selleck was born on January 29, 1945, in Detroit, Michigan, and grew up in Sherman Oaks, California. From an early age, he was involved in sports, particularly basketball. which played a significant role in his physical development. His athletic pursuits continued into college. where he attended the University of Southern California (USC) on a basketball scholarship. This early involvement in sports laid a strong foundation for his physical health and disciplined lifestyle.
Transition to Acting
Selleck's transition from an athlete to an actor came with its physical demands. His first significant role in "Magnum P.I." required him to perform various stunts and maintain a fit appearance. This role, which he played from 1980 to 1988. necessitated a rigorous fitness routine to meet the show's demands. setting the stage for his long-term commitment to health and wellness.
Fitness Regimen
Workout Routine
Tom Selleck health and fitness regimen has evolved. adapting to his changing roles and age. During his "Magnum, P.I." days. Selleck's workouts were intense and focused on building and maintaining muscle mass. His routine included weightlifting, cardiovascular exercises. and specific training for the stunts he performed on the show.
Selleck adjusted his fitness routine as he aged to suit his body's needs. Today, his workouts focus on maintaining flexibility, strength, and cardiovascular health. He incorporates low-impact exercises such as swimming, walking, and light weightlifting. This balanced approach helps him stay fit without putting undue strain on his joints and muscles.
Importance of Flexibility and Mobility
In recent years, Selleck has emphasized the importance of flexibility and mobility in his fitness regimen. Understanding the natural decline in muscle mass and joint flexibility with age. he includes stretching and yoga in his routine. These practices help prevent injuries, improve posture, and maintain mobilit
Explore natural remedies for syphilis treatment in Singapore. Discover alternative therapies, herbal remedies, and lifestyle changes that may complement conventional treatments. Learn about holistic approaches to managing syphilis symptoms and supporting overall health.
New Directions in Targeted Therapeutic Approaches for Older Adults With Mantl...i3 Health
i3 Health is pleased to make the speaker slides from this activity available for use as a non-accredited self-study or teaching resource.
This slide deck presented by Dr. Kami Maddocks, Professor-Clinical in the Division of Hematology and
Associate Division Director for Ambulatory Operations
The Ohio State University Comprehensive Cancer Center, will provide insight into new directions in targeted therapeutic approaches for older adults with mantle cell lymphoma.
STATEMENT OF NEED
Mantle cell lymphoma (MCL) is a rare, aggressive B-cell non-Hodgkin lymphoma (NHL) accounting for 5% to 7% of all lymphomas. Its prognosis ranges from indolent disease that does not require treatment for years to very aggressive disease, which is associated with poor survival (Silkenstedt et al, 2021). Typically, MCL is diagnosed at advanced stage and in older patients who cannot tolerate intensive therapy (NCCN, 2022). Although recent advances have slightly increased remission rates, recurrence and relapse remain very common, leading to a median overall survival between 3 and 6 years (LLS, 2021). Though there are several effective options, progress is still needed towards establishing an accepted frontline approach for MCL (Castellino et al, 2022). Treatment selection and management of MCL are complicated by the heterogeneity of prognosis, advanced age and comorbidities of patients, and lack of an established standard approach for treatment, making it vital that clinicians be familiar with the latest research and advances in this area. In this activity chaired by Michael Wang, MD, Professor in the Department of Lymphoma & Myeloma at MD Anderson Cancer Center, expert faculty will discuss prognostic factors informing treatment, the promising results of recent trials in new therapeutic approaches, and the implications of treatment resistance in therapeutic selection for MCL.
Target Audience
Hematology/oncology fellows, attending faculty, and other health care professionals involved in the treatment of patients with mantle cell lymphoma (MCL).
Learning Objectives
1.) Identify clinical and biological prognostic factors that can guide treatment decision making for older adults with MCL
2.) Evaluate emerging data on targeted therapeutic approaches for treatment-naive and relapsed/refractory MCL and their applicability to older adults
3.) Assess mechanisms of resistance to targeted therapies for MCL and their implications for treatment selection
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MANAGEMENT OF ATRIOVENTRICULAR CONDUCTION BLOCK.pdfJim Jacob Roy
Cardiac conduction defects can occur due to various causes.
Atrioventricular conduction blocks ( AV blocks ) are classified into 3 types.
This document describes the acute management of AV block.
2. There are three general mechanisms of ACL failure:
•External rotation and abduction with hyperextension
•Direct forward displacement of the tibia
•Internal rotation with the knee in full extension.
With varus or valgus stress, the ACL is injured after collateral
ligament failure.
Forced valgus in external rotation is the most common
mechanism of injury and causes disruption of the MCL and
medial supporting structures.
ACL Tears
3. Primary Signs
•Abnormal ligament course (abnormal Blumensaat angle)
•Abnormal ligament signal intensity (coronal images
should be used in conjunction with sagittal images to
compensate for segmental visualization in the sagittal
plane)
•Ligament discontinuity
(MRI findings)
4. Secondary Signs
•Lateral compartment ossesous contusions (posterolateral tibial
plateau is most specific)
•Posteromedial tibial plateau contusion or fracture
•Anterior tibial displacement (assessed in the lateral aspect of the
lateral compartment)
•Uncovered posterior horn lateral meniscus
•Posterior cruciate line and angle.
•Chronic ACL tears demonstrate resolution of the ossesous
contusions, effusions, synovitis, and ligamentous hyperintensity
that are characteristic of acute injuries unless seen in the setting
of an acute injury.
5. The Blumensaat line courses parallel to the roof of the intercondylar notch (the
posterior surface of the femur). The Blumensaat angle is formed by the
Blumensaat line and a line along the margin (including the distal portion) of the
ACL. A negative (normal) Blumensaat angle occurs when the apex of the angle
is directed superiorly, and a positive (abnormal) Blumensaat angle occurs when
the apex of the angle is directly inferior.
Blumensaat angle
6. The posterior cruciate line
A line was drawn tangent to the posterior margin of the distal posterior cruciate
ligament and extended proximally. The posterior cruciate line was considered to
be positive for ACL tear if the proximal extension of this line did not intersect the
medullary cavity of the femur within 5 cm of its distal aspect.
This sign was considered to be negative if the proximal extension of the posterior
cruciate ligament line intersected the medullary cavity within 5 cm of its distal
aspect.
7. The posterior cruciate angle was defined as the point of intersection between
lines drawn through the proximal and distal portions of the posterior cruciate
ligament.
A posterior cruciate angle measurement less than the mean value (114.8°) for all
cases was used as the threshold for the diagnosis of ACL tear.
8. (A)Acute ACL rupture of
proximal fibers. The
slope of the ACL is
decreased relative to
the intercondylar roof
(Blumensaat's line).
Characteristic
posterolateral tibial
plateau contusion is
demonstrated.
(B) Sagittal and
(C) axial FS PD FSE images
of a grade 3 ACL tear.
Complete loss of
proximal ligament
continuity with the
lateral femoral condyle
side wall is shown in both
sagittal and axial
planes. Acute findings of
a joint effusion and
posterior tibial plateau
contusion are present.
9. ACL tears are classified into three grades:
Grade I ACL tears represent intraligamentous injury without a change
in ligament length.
Grade II ACL tears represent intraligamentous injury and an increase
in ligament length.
Grade III ACL tears represent complete ligamentous disruption.
10. Grade 1 to 2 ACL sprain.
(A)On PD FSE images the ligament demonstrates intermediate signal
intensity.
(B) On corresponding FS PD FSE coronal images the ligament demonstrates
continuity.
Loss of ligament hypointensity on a T1- or PD-weighted sequence is a
sensitive sign of ligamentous strain or scarring. The FS PD sequence is specific
for ligament continuity and can be used to differentiate a grade 2 from a
grade 3 ACL sprain.
11. Grade 3 ACL tear- Disruption of the middle third of the ACL (FS PD FSE sagittal
image)
12. The lateral femoral notch sign has been described as an indirect sign of a torn
ACL.
The depth of the lateral condylopatellar sulcus on the lateral radiograph can be
measured by drawing a tangent line across the sulcus on the articular surface
of the lateral femoral condyle. The depth of the sulcus is then measured
perpendicular to this line at its deepest point.
Sulcus deeper than 1.5 mm, was a reliable indirect conventional radiographic
sign of a torn ACL.
Deep sulcus sign
13. Posterior Cruciate Ligament (PCL) tear
The PCL is twice as strong as the ACL, with a larger cross-sectional area
and higher tensile strength. These features account for a lower
incidence of rupture of the PCL.
Tears of the PCL are most common in the midportion (76%), followed
by avulsions from the femur (36% to 55%) and the tibia (22% to 42%).
Rupture may be caused by excessive rotation, hyperextension,
dislocation, or direct trauma while the knee is flexed.
Motor vehicle accidents (dashboard injuries) and injuries sustained in
contact sports such as football are the most common causes of
damage to the PCL .
Injuries to the PCL are usually associated with tears of the ACL, the
meniscus, collateral ligaments, or postero-lateral structures .
14. (A)Dashboard injury caused by a posteriorly directed force applied to the
proximal tibia with the knee in 90° of flexion.
This sagittal FS PD FSE image shows complete loss of PCL continuity secondary to
a complex interstitial PCL tear.
(B) Axial FS PD FSE image showing an anterolateral fracture resulting from direct
trauma by the dashboard during impact.
15.
16. Normal Meniscal Anatomy
Medial meniscus
Both horns are triangular in shape and have very sharp points.
The posterior horn is always larger than the anterior horn (figure).
If this is not the case than the shape is abnormal, which can be a sign of a
meniscal tear or a partial meniscectomy.
17. The posterior root is immediately anterior to the posterior cruciate ligament.
If it is missing on the sagittal images, then there is a meniscal root tear (figure).
18. Lateral meniscus
On sagittal images the posterior horn is higher in position than the
anterior horn.
Both horns are about the same size.
19. Meniscal tears
Criteria for tears
The two most important criteria for meniscal tears are an abnormal
shape of the meniscus and high signal intensityon PD-images
unequivocally contacting the surface .
Nomenclature of Meniscal Tears
Shapes. There are 3 basic shapes of meniscal tears: longitudinal,
horizontal and radial .
Complex tears are a combination of these basic shapes.
21. Longitudinal tears
Longitudinal tears parallel the long axis of the meniscus dividing the
meniscus in an inner and outer part.
So the distance between the tear and the outer margin of the meniscus is
always the same (figure).
The tear never touches the inner margin.
22. Bucket-Handle Tears
A displaced longitudinal
tear of the meniscus,
usually the medial
meniscus, is called a
bucket-handle tear
because the separated
central fragment
resembles the handle of
a bucket.
The remaining larger
peripheral section of the
meniscus is the bucket.
23. Bucket-Handle Tears
• An unstable meniscal fragment locks into the intercondylar notch
and involves at least two thirds of the meniscal circumference.
• Diagnosis of a bucket-handle tear requires identification of
displaced meniscal tissue from posterior to a relative anterior coronal
location.
• A double delta sign and/or a double PCL sign are sagittal MR
findings of a displaced bucket-handle tear.
• Medial meniscus bucket-handle tears are three times more frequent
than bucket-handle tears involving the lateral meniscus.
• A bucket-handle tear effectively reduces the width of the meniscus,
and peripheral sagittal images fail to demonstrate the normal
bowtie configuration of the body of the meniscus.
24. Double PCL sign
• The double PCL sign refers to visualization of the
displaced meniscal fragment anterior to the PCL in the
intercondylar notch.
Double delta sign
• The double delta sign refers to visualization of flipped
inner meniscal fragments adjacent (posterior) to the
anterior horn of the donor site.
• The double delta sign is produced by two triangular
structures adjacent to each other anteriorly.
25. The body of the medial meniscus show a bucket handle tear with intra articular
displacement of a large meniscal fragment.
29. Radial tears
Radial tears are perpendicular to the long axis of the meniscus.
They violate the collagen bundles that parallel the long axis of the
meniscus.
These are high energy tears. They start at the inner margin and go
either partial or all the way through the meniscus dividing the
meniscus into a front and a back piece.
Radial tears are difficult to recognize. You have to combine the
findings on sagittal and coronal images to make the diagnosis.
The following combination of findings is diagnostic:
In one plane: triangle missing the tip and
in the other plane: a disrupted bow tie.
30.
31. Small radial tears are difficult to diagnose.
Sometimes the only sign is a disrupted bow tie.
32. Meniscal root tear
A meniscal root tear is a radial tear located at the meniscal root.
Normally when you image the posterior cruciate ligament on sagittal
images you should see a considerable posterior horn of the meniscus
on that image or the image adjacent to it.
If this is not the case it is an absent or empty meniscus-sign indicating
a root tear.
33. Medial collateral ligament
The superficial medial collateral ligament (MCL) extends from the medial
epicondyle to insert not just near the joint but 7 cm below the joint space.
At that point there are three landmarks: the inferomedial geniculate
artery and paired veins (figure).
The deep part of the MCL, even when it is normal, you may not be able
to see.
34. Injuries of the of the medial collateral ligament are graded into three
groups on MRI, much in the same way as many other ligaments.
grade 1: (minor sprain) high signal is seen medial (superficial) to the
ligament, which looks normal
grade 2 : (severe sprain or partial tear) high signal is seen medial to the
ligament, with high signal or partial disruption of the ligament
grade 3 : complete disruption of the ligament
35.
36. Chondromalacia patellae
Chondromalacia patellae refers to softening and degeneration of the
articular hyaline cartilage of the patella, and is a frequent cause of
anterior knee pain.
MRI
T1
• poor sequence for cartilage and surface irregularity and subtly
signal change may be inapparent
• areas of hypointensity may be seen in cartilage
• sub-chondral reactive bone marrow oedema pattern (low signal)
• secondary changes of osteoarthritis may be seen
T2 / PD
• best sequences for assessing cartilage
• abnormal cartilage is usually of high signal compared to normal
cartilage
• findings range from subtle increase in signal to complete loss of
cartilage
37. Chondromalacia grading
grade I
focal areas of hyperintensity with normal contour
arthroscopically : softening or swelling of cartilage
grade II
blister-like swelling/ fraying of articular cartilage extending to surface
arthroscopically : fragmentation and fissuring within soft areas of
articular cartilage
grade III
partial thickness cartilage loss with focal ulceration
arthroscopically : partial thickness cartilage loss with fibrillation (crab-
meat appearance)
grade IV
full thickness cartilage loss with underlying bone reactive changes
arthroscopically : cartilage destruction with exposed subchondral
bone
39. Bone Contusion Patterns
The distribution of bone marrow edema is like a footprint left behind
at injury, providing valuable clues to the associated soft-tissue
injuries.
Five contusion patterns with associated soft-tissue injuries occur in
the knee:
• pivot shift injury,
• dashboard injury,
• hyperextension injury,
• clip injury, and
• lateral patellar dislocation.
40. Pivot shift injury.
Drawing shows a skier with a right
knee pivot shift injury (knee valgus,
femur internally rotated).
Drawing shows that, with the foot
planted, the combination of valgus
stress on the knee and internal rotation
of the femur results in disruption of the
ACL.
After disruption of the ACL, the tibia is
free to sublux anteriorly relative to the
femur. This movement results in the
impaction of the lateral femoral
condyle against the posterolateral tibial
plateau.
41. classic bone marrow edema pattern resulting from pivot shift injury of the
knee.
Extensive contusion is present in the posterolateral tibial plateau (straight
arrow) and, to a lesser degree, the lateral femoral condyle (curved arrow)
42. Dashboard injury.
Drawing shows a woman striking her
knee against the dashboard during an
automobile accident. This is the most
common mechanism of injury resulting
in disruption of the PCL.
The tibia is forced posteriorly (open arrow)
relative to the femur. The crosshatched region
indicates the area of bone contusion on the
anterior tibia caused by direct trauma.
The PCL is usually tight when the knee is in 90° of
flexion and is, therefore, at risk for disruption
(solid arrow).
The ACL, on the other hand, is normally lax while
the knee is flexed and usually remains intact.
43. Sagittal T2-weighted fast SE image demonstrates edema in the anterior
proximal tibia (white arrow) and complete disruption of the PCL (black
arrow)
44. Hyperextension injury.
Drawing depicts a forceful kicking
motion resulting in a hyperextension
injury of the right knee.
Drawing shows how very severe
hyperextension of the knee (arrow) can result
in the impaction of the anterior aspect of the
femoral condyle against the anterior aspect of
the tibial plateau.
The crosshatched regions indicate the areas of
bone contusion.
Depending on the amount of force applied
during hyperextension, tears of the ACL, PCL,
or both may occur.
45. Coronal T2-weighted fast SE MR image obtained with fat saturation
reveals kissing bone marrow contusions (arrows) of the medial aspect of
the anterior tibia and femur secondary to the hyperextension injury.
46. Clip injury.
Drawing shows the typical mechanism
of a clip injury to the right leg, resulting
from a valgus force to the lateral
aspect of the knee while the knee is in
slight flexion.
Drawing shows that the larger area of bone
contusion (large crosshatched region) results
from a direct force (open arrow) to the lateral
femoral condyle.
A smaller area of edema (small crosshatched
region) may occur within the medial femoral
condyle or the medial tibial plateau due to an
avulsive injury of the MCL related to the valgus
stress
47. Coronal T2-weighted image shows a large area of contusion involving the
lateral femoral condyle (long white arrow).
Minimal edema is noted within the medial femoral condyle (short white
arrow). T
he edema is distal to the attachment site of the MCL and is likely secondary
to impaction. The MCL is partially disrupted (black arrow).
48. Lateral patellar dislocation.
Drawing shows the classic mechanism
of injury: fixed tibia, internal femoral
rotation, and quadriceps contraction.
Drawing demonstrates transient lateral
dislocation of the patella, which results in
impaction of the medial patellar facet against
the lateral femoral condyle.
The crosshatched regions reveal the typical
areas of bone contusion involving the
inferomedial patella and the anterolateral
femoral condyle.
The distraction forces frequently cause
disruption of the medial retinaculum and the
MPFL.
49. Axial T2-weighted image demonstrates the classic bone marrow
contusion pattern involving the inferior aspect of the medial patellar
facet (curved arrow) and the anterior aspect of the lateral femoral
condyle (straight solid arrow).
The amorphous appearance of the medial retinaculum with extensive
signal intensity abnormality represents disruption (open arrow).