Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Core > MSK: Trauma and Overuse, Knee/Tibia/Fibula > Flashcards

MSK: Trauma and Overuse, Knee/Tibia/Fibula Flashcards

1
Q
A

Reverse segond fracture, recommend MRI to look for PCL tear and/or medial meniscus injury

Note: Fracture of the medial tibial plateau.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q
A

Segond fracture, recommend MRI to look for ACL tear

Note: Fracture of the lateral tibial plateau.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

A segond fracture is a fracture of the…

A

Lateral tibial plateau

Note: A reverse segond fracture involves the medial tibial plateau.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Segond fractures are associated with…

A

ACL tear (75%)

Note: Recommend an MRI if you see one.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is usually the mechanism of injury for this fracture?

A

Segond fractures typically occur during internal rotation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Reverse segond fractures are associated with…

A
  • PCL tear
  • Medial meniscus injury
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is usually the mechanism of injury for this fracture?

A

Reverse segond fractures usually occur during external rotation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q
A

Avulsion fracture of the proximal fibula (at the insertion site of the arcuate ligament complex), recommend MRI to look for ACL/PCL tear

Note: This is the “arcuate sign”.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

This type of fracture is associated with…

A

ACL or PCL injury (90%)

Note: This is the “arcuate sign” (proximal fibula avulsion fracture at the insertion of the arcuate ligament complex).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q
A

Lateral femoral notch sign (AKA deep intercondylar notch sign), recommend MRI to look for an ACL tear

Note: Depression fracture of the lateral femoral condyle (terminal sulcus) that occurs due to an impaction injury and is associated with ACL tears.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

The lateral femoral notch sign is associated with…

A

ACL tears

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are the components of the anterior cruciate ligament?

A
  • Anteromedial bundle
  • Posterolateral bundle
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is the strongest ligament of the knee?

A

The PCL

Note: This is good because it prevents posterior dislocations of the knee (which could result in dissection of the popliteal artery).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

The IT band inserts on…

A

Gerdy’s tubercle (on the lateral tibia)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Is the ACL intraarticular?

A

The ACL is intraarticular, but extrasynovial

Note: The synovium folds around the ligament (which is how you can have a torn ACL even with an intact synovium). This is also why a torn ACL rarely heals on its own.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Is the PCL intraarticular

A

The PCL is intraarticular, but extrasynovial (like the ACL)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Is the MCL intraarticular?

A

The MCL is extraarticular

Note: MCL fibers are interlaced with the joint capsule.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

MCL fibers interlace with the…

A

Knee joint capsule and medial meniscus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Merging of the _______ and the ______ creates the conjoint tendon of the knee, which inserts on the fibula head

A
  • Biceps femoris tendon
  • Lateral collateral ligament
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Can you have an ACL tear without disrupting the synovium?

A

Yes, the ACL is intraartciular but extrasynovial

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q
A

Magic angle artifact

Note: This occurs when the tendon/ligament forms a 55 degree angle with the main magnetic field (only on short TE sequences).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

At what angle does the magic angle artifact happen?

A

55 degrees to the main magnetic field

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What sequence can you check to ensure a lesion is due to magic angle artifact?

A

T2

Note: Magic angle artifact is not present on long TE sequences (e.g. T2).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Magic angle artifact can be seen on what sequences?

A

Short TE sequences (e.g. T1, proton density, GRE)

Note: It is not present on T2 (long TE sequence).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q
A

ACL tear

Note: Kissing contusions (95% specific for ACL tear in adults).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What is the common mechanism of injury in an ACL tear?

A

Pivot shifting

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

ACL tears are associated with what fractures?

A
  • Segond fracture (lateral tibial plateau)
  • Tibial spine avulsion fracture
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What is the ACL being compared to here?

A

The Blumensaat line, AKA intercondylar line (a line drawn along the roof of the intercondylar notch of the femur on a sagittal image)

Note: If the ACL is more horizontal than the Blumensaat line, there is likely an ACL tear (figure B).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

O’donoghue’s unhappy triad

A
  • ACL tear
  • MCL tear
  • Medial meniscus tear

Note: This usually occurs due to a blow to the lateral knee during contact sports.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q
A

Osteochondral injury suggestive of an ACL tear

Note: This develops when this location impacts on the posterior tibia (which also gives the kissing contusions).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Positive anterior drawer test on clinical exam…

A

ACL tear

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

What happened to this ACL?

A

Mucoid degeneration (look for other signs e.g. contusions, meniscal tears to suggest acute injury)

Note: Very striated appearance on T2/STIR (“celery stalk” appearance).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q
A

ACL ganglion cyst

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

Mucoid degeneration of the ACL predisposes to…

A

ACL ganglion cysts

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

What are the two main methods of ACL repair?

A
  • Using graft from the semitendinosus and/or gracilis tendons (better)
  • Using the middle 1/3 of the patellar tendon (worse)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

What procedure has been performed?

A

ACL repair

Note: Femoral and tibial ACL graft tunnels.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

What is the normal appearance of the tibial tunnel when evaluating an ACL repair?

A
  • Tunnel should be parallel to the roof of the femoral intercondylar notch (Blumensaat line)
  • Tunnel should be entirely posterior to Blumensaat line
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

What complications might a pt have if this was their tibial tunnel location s/o ACL repair?

A
  • Roof impingement (tunnel is too far anterior and the graft might get impinged on the intercondylar roof)
  • Graft impingement on the femur during extension (tunnel is too steep, should be parallel to blumensaat line)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

Arthrofibrosis

A

Excessive scar tissue formation within a joint capsule (following trauma or orthopedic surgery), which can lead to pain and stiffness of the joint

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

Palpable, audible clunk when evaluating an ACL repair clinically…

A

Think arthrofibrosis (excessive intracapsular scar tissue formation)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

When does arthrofibrosis tend to develop after ACL repair?

A

About 16 weeks after surgery

Note: This is a later complication resulting from excessive scar tissue formation.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q
A

Cyclops lesion (i.e. focal arthrofibrosis)

Note: Scar tissue formation at the apex of Hoffas fat pad, usually as a complication of ACL repair.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q
A

Cyclops lesion (i.e. focal arthrofibrosis)

Note: Scar tissue formation at the apex of Hoffas fat pad, usually as a complication of ACL repair.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

Reduced range of motion with history of ACL repair

A

Cyclops lesion (i.e. focal arthrofibrosis)

Note: Scar tissue formation at the apex of Hoffas fat pad, usually as a complication of ACL repair.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

History of ACL repair

A

ACL graft tear

Note: The ACL fibers are more horizontal than blumensaat line (intercondylar roof line).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

When is an ACL graft most susceptible to tear?

A

During the remodeling phase (4-8 months post op)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

Imaging findings of ACL graft tear

A
  • ACL graft is more horizontal than blumensaat line
  • Grossly high T2 signal in graft (some T2 signal is ok)
  • Fiber discontinuity
  • Anterior tibial translation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

What is often missed and commonly results in ACL reconstruction failure?

A

A posterolateral corner injury

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

What are the most significant structures that may need to be surgically repaired in a posterolateral corner injury?

A
  • Lateral collateral ligament
  • Biceps femoris muscle and tendon
  • Popliteus muscle/tendon

Note: The LCL and biceps femoris for the conjoint tendon that inserts on the fibula head.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

Trauma

A

Posterolateral corner injury of the knee

Note: Edema in the fibula head should make.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

What is a posterolateral corner injury of the knee?

A

An injury to the posterolateral ligamentous complex (in the region of where the conjoint tendon attaches to the fibular head)

Note: This often results in knee instability and ACL reconstruction failure if not recognized.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

What are the main components of the posterolateral ligament complex?

A
  • Conjoint tendon (LCL and biceps femoris tendons)
  • Popliteus muscle
  • Popliteofibular ligament

Note: Many other additional structures are sometimes considered part of the complex (and sometimes not).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

Major trauma with PCL tear…

A

Think posterior dislocation of the knee, recommend CTA runoff to look for popliteal artery injury

54
Q

Next step:

A

CTA runoff (to look for popliteal artery injury)

Note: Posterior knee dislocation should get a CTA.

55
Q

Major trauma

A

PCL tear suggestive of transient posterior knee dislocation, recommend CTA runoff (to look for popliteal artery injury)

56
Q

Which meniscus is visible?

A

The lateral meniscus

Note: You see the fibula. The lateral meniscus should look like a bowtie (equal anterior and posterior thickness).

57
Q

Which meniscus is visible?

A

The medial meniscus

Note: The medial meniscus is thicker posteriorly.

58
Q

Blue arrow

A

Transverse ligament (AKA meniscomeniscal ligament)

59
Q

Where are meniscal tears less likely to heal?

A

In the more central avascular white zone

Note: The more peripheral red zone is vascular and may heal without intervention.

60
Q

Horizontal vs vertical meniscal tears

A

Note: This is determined on sagittal imaging.

61
Q

What are the major types of meniscal tears?

A
  • Basic
  • Complex
  • Displaced
62
Q

What are the major types of basic meniscal tears?

A
  • Longitudinal tears (horizontal and vertical)
  • Radial tears
  • Root tears
63
Q

What are the major types of displaced meniscal tears?

A
  • Flap tear
  • Bucket-handle tear
  • Parrot beak tear
64
Q

Why are radial tears bad?

A

Radial tearing cuts through the circular “hoop” fibers that keep the meniscus together

Note: This is why radial tears often lead to extrusion, early osteoarthritis, etc.

65
Q

Name all of the meniscal tear types

A
66
Q

What is a flap tear of the meniscus?

A

A horizontal longitudinal tear with displacement of the flap

67
Q

What is a bucket handle meniscal tear?

A

A vertical longitudinal tear with displacement of the flap

68
Q
A

Radial meniscal tear

Note: This is the “truncated triangle” sign.

69
Q

What is the marching cleft sign of meniscal tears?

A

When a meniscal tear appears to march inward/outward on sagittal imaging, suggesting a radial tear

70
Q

What is the ghost sign of meniscal tears?

A

Sudden disappearance of a meniscal horn while scrolling through sagittal images, suggesting a radial tear

71
Q
A

Radial meniscal tear of the posterior horn of the medial meniscus

Note: This is the “ghost” sign. You know its the medial meniscus because the medial tibia looks like a golf tee (the lateral looks like a hockey stick to accommodate the fibula).

72
Q

What type of meniscal tear?

A

Parrot beak tear (a radial tear that becomes horizontal with displacement of the flap)

73
Q

Which meniscus is more likely to be discoid?

A

The lateral meniscus

74
Q
A

Discoid lateral meniscus

75
Q

How can you tell whether there is a discoid meniscus on sagittal images?

A

3 or more bowties

76
Q

Why is it not great to have a discoid meniscus?

A

They are more prone to meniscal tears

77
Q

How can you tell whether there is a discoid meniscus on coronal images?

A

Meniscus extends centrally and reaches the intercondylar notch

Note: A transverse length > 15 mm is diagnostic.

78
Q

What structure is this?

A

Wrisberg ligament

79
Q

Which variant of discoid meniscus is the most prone to injury?

A

Wrisberg variant

Note: This is also the rarest variant.

80
Q

Pediatric pt with a meniscal tear…

A

Think discoid meniscus

81
Q

Which meniscus is more prone to bucket handle tears?

A

Medial meniscus (80%)

82
Q
A

Bucket handle meniscal tear

Note: This is the “double PCL” sign.

83
Q

You only see 1 “bowtie” appearance of the medial meniscus on all sagittal slices…

A

Think bucket handle meniscal tear

84
Q

Would you expect the ACL to be intact?

A

Yes, the double PCL sign of a bucket handle tear only occurs in the setting of an intact ACL

85
Q

Meniscal cysts are associated with…

A

Meniscal tears (most often horizontal cleavage tears)

86
Q
A

Meniscal ossicle

87
Q

Where does a Bakers cyst occur?

A

Between the semimembranosus tendon and the medial head of gastrocnemius

88
Q
A

Meniscocapsular separation

Note: This is when the capsular ligament (deepest layer of the MCL complex) is torn away from the meniscus.

89
Q

Meniscocapsular separation is often the result of a…

A

Proximal MCL tear

90
Q

Treatment for meniscocapsular separation

A

Immobilization or surgery

Note: This is a serious injury.

91
Q
A

Ligament of wrisberg

92
Q
A

Wrisberg pseudotear

Note: This is a cleft between the lateral meniscus posterior horn and the wrisberg ligament.

93
Q

What are the red and yellow circles?

A

Red: Humphry ligament (anterior to PCL)

Yellow: Wrisberg ligament (posterior to PCL)

Note: “Wrisberg is humping Humphry” also H comes anteriorly in the alphabet compared to W. Both of these ligaments attach to the lateral meniscus posterior horn.

94
Q
A

Meniscal flounce

Note: This is a meniscal tear mimic, but is not associated with an increased risk of tear.

95
Q

Does meniscal flounce increase the risk of tearing?

A

No

96
Q

In which direction does the patella tend to dislocate?

A

Laterally

97
Q

Patellar dislocations are associated with tears of the…

A

Medial patellofemoral ligament

98
Q
A

Patella dislocation

99
Q

What is a major risk factor for patella dislocation?

A

Trochlear dysplasia (femoral trochlea being too flat)

100
Q

What procedure was done?

A

Tibial tuberosity transfer (to stabilize the patellofemoral joint in pts with patellar instability)

101
Q

20 y/o M

A

Bipartite patella

Note: Normally the patella should fuse by age 12.

102
Q

Where will the “fragment” be in a bipartite patella?

A

Superolateral

103
Q

Bilateral patella tendon rupture…

A

Think chronic steroid use

104
Q
A

Patella alta

Note: This can be seen in patellar tendon rupture.

105
Q
A

Patella baja

Note: This can be seen in quadriceps tendon rupture.

106
Q

Risk factors for patella tendon rupture

A
  • Systemic lupus erythematosus (classic)
  • Old age
  • Renal failure
  • Rheumatoid arthritis
  • Chronic steroids
107
Q
A

Prepatellar bursitis

108
Q
A

Hoffas fat pad impingement syndrome

109
Q
A

Jumpers knee

Note: High T2 signal in the patellar tendon near its patellar attachment.

110
Q
A

Lateral tibial plateau fracture

111
Q

Fall from height

A

Tibial plateau fracture with lipohemarthrosis

112
Q

Which tibial plateau is more likely to fracture?

A

The lateral tibial plateau

113
Q
A

Pilon fracture (comminuted tibial plafond fracture with articular impaction)

114
Q

In 75% of cases, a pilot fracture is associated with a fracture of the…

A

Distal fibula

115
Q

Pilon fracture

A

Comminuted tibial plafond fracture with articular impaction

Note: These are associated with distal fibula fractures in 75% of cases.

116
Q

What is the most common long bone fracture?

A

Tibial shaft fracture

Note: The tibia is also one of the slowest bones to heal (~10 weeks).

117
Q

14 y/o M

A

Juvenile Tillaux fracture (a type 3 Salter-Harris fracture through the anterolateral aspect of the distal tibial epiphysis)

118
Q

In what direction does the distal tibial growth plate close?

A

From medial to lateral

Note: This is why juvenile Tillaux fractures (which require a partially open growth plate) occur on the lateral aspect of the tibial plafond.

119
Q
A

Juvenile Tillaux fracture (a type 3 Salter-Harris fracture through the anterolateral aspect of the distal tibial epiphysis)

120
Q

When can you get a juvenile Tillaux fracture

A

Ages 12-15 (it requires a partially closed distal tibial physis that is still open laterally)

121
Q
A

Triplane fracture (a type 4 Salter-Harris fracture through the epiphysis and metaphysis of the distal tibia)

122
Q

Triplane fracture

A

A type 4 Salter-Harris fracture of the distal tibia (fracture extends in 3 planes through the epiphysis, physis, and metaphysis)

Note: It is the extension through the posterior metaphysis that distinguishes this from a Tillaux fracture (which is a 2 plane fracture through the epiphysis and physis).

123
Q

Next step:

A

Dedicated tibia fibula radiographs (to look for a proximal fibula fracture)

Note: Always image the proximal lower leg if you see a widened ankle mortise to look for a proximal fibula fracture (which would make this a Maisonneuve fracture).

124
Q
A

Maisonneuve fracture (an unstable fracture involving the medial tibial malleolus and/or disruption of the distal tibiofibular syndesmosis AND a proximal fibula fracture)

125
Q

What ankle radiograph findings should make you suspect a Maisonneuve or high Weber C fracture and recommend dedicated tibia/fibula radiographs to look for a proximal fibula fracture?

A
  • Isolated fracture of the medial malleolus
  • Widening of the medial ankle mortise (or any painful swelling/hematoma over the medial malleolus without a visible fracture)
  • Isolated fracture of the posterior malleolus
126
Q

Next step if there are no other fractures:

A

Dedicated tibia/fibula radiographs (to look for a proximal fibula fracture, which would make this a high Weber C fracture)

127
Q
A

Adult-type Tillaux fracture (fracture of the anterolateral tibial epiphysis)

Note: This occurs when the growth plate is fully closed, unlike a juvenile Tillaux fracture (which is a type 3 Salter-Harris fracture that requires a partially open physis).

128
Q
A

Lateral malleolar fracture (Weber A, stable)

129
Q
A

Bimalleolar fracture (Weber A, unstable)

Note: Weber A because the distal fibula fracture is horizontal (even through it looks to be at the level of the syndesmosis, a Weber B should be oblique).

130
Q
A

Weber C fracture, unstable

Note: Widening of the medial ankle mortise and a high fibular fracture. This indicates that the tibiofibular syndesmosis is disrupted and the fracture is unstable.

131
Q

Weber classification of ankle fractures

A

Classifies lateral malleolar fractures based on their relationship to the distal tibiofibular syndesmosis

Core (98 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions