LE Trauma Flashcards
Powerful musculature of the thigh usually is the cause of frequent
displacement
femoral shaft injury
Femoral shaft injury can cause fatty marrow escape into circulation which may lead to
fat pulmonary embolism
3 types of femoral shaft fractures:
Type I - Spiral or transverse (most common)
Type II - Comminuted
Type III - Open
m/c type of femoral shaft fracture
Type I - Spiral or transverse
After signifiant trauma or as a pathological fracture due to metastatic bone
disease or primary bone neoplasms or other osseous pathology
Diaphysis fracture
Increased use of Bisphosphanates medications in treatment of osteoporosis
may result in
femoral shaft fractures
Clinical manifestations of femoral shaft fracture
- severe pain
- inability to stand or ambulate
- regional and systemic
complications such as neurological and vascular injury
m/c type of femoral shaft fracture
spiral or transverse-oblique fracture
may involve bayonet deformity
Often intra-articular and frequently comminuted
Supracondylar and Condylar distal femur fracture
Supracondylar and Condylar distal femur fractures usually occur as a result of?
1) low-energy trauma in osteoporotic bone in the elderly
2) high-energy trauma in young patients
clinical signs of supracondylar and condylar distal femur fracture?
Pain, deformity, weakness, and inability to ambulate/stand
complications for supracondylar and condylar distal femur fracture?
- compartment syndrome
- vascular and nerve injury
key mechanism of
injury leading to fracture in osteoporotic
patients
Low force or even trivial trauma
may develop following total knee arthroplasty
Supracondylar fractures
two configurations types for femoral condyle fractures
“T” or “Y”
always intraarticular
Femoral condyle fractures can be complicated by
delayed healing and comminuted fragments.
Femoral condyle fractures may co-exist with
Tibial plateau fracture
were originally termed a bumper or fender fracture
Tibial plateau fractures
what % of tibial plateau fractures result from impact with automobile
bumpers
25%
most common
mechanism of tibial plateau fractures
Axial loading I.e. fall from a height
In younger patients the tibial plateau fracture often involves
splitting
In older, osteoporotic patients, what type of fractures are typically are seen?
(difficult to detect radiographically)
depression fractures
occur in
approximately 10% of patients with tibial plateau fracture
Soft tissue injuries (e.g. to cruciate and collateral ligaments)
Fractures of the lateral or medial tibial plateau or more common?
lateral plateau from lateral femoral condyle
Type 1 Shatzker tibial plateau fracture
wedge (low force)
Type 2 Shatzker tibial plateau fracture
wedge with depression
Type 3 Shatzker tibial plateau fracture
depression with no wedge
Type 4 Shatzker tibial plateau fracture
Like type 1 but invovles medial plateau
Type 5 Shatzker tibial plateau fracture
both plateaus
Type 6 Shatzker tibial plateau fracture
both plateaus + part of proximal metaphysis/diaphysis
results from an intra-articular fracture with escape of
fat and blood from the bone marrow into the knee joint
Lipohemarthrosis
Lipohemarthrosis is most frequently associated with what fracture?
tibial plateau fracture or distal femoral
fracture
Patella fractures may also result in
lipohemarthrosis
sign of lipohemarthrosis
FBI sign or fat-blood-interphase
Fat-fluid level is seen on any horizontal beam radiograph, but best achieved with what view?
cross-table horizontal lateral view
Indication of intra-articular/intra-capsular fracture about the knee,
typically tibial plateau fractures
FBI sign
may occur especially in young or adolescent
patients as a result of pull and tear by the ACL
Tibial spine avulsion
avulsion likely from pull of lateral capsular knee ligaments and
possibly IT band
Segond fractures
Important radiographic clue to ACL tear
Segond fracture-avulsion
occur in children
while jumping on a trampoline
Transverse fractures of the proximal tibial metaphysis (trampoline fracture)
most often seen in children 2
to 5 years of age.
trampoline fracture
Most occur in adolescents
with immature bone and active growth apophysis
Tibial tuberosity avulsion fractures (uncommon)
Associated with sports and jumping
Tibial tuberosity avulsion fractures
Tibial tuberosity avulsion fractures occurs with
violent contraction
of quadriceps or passive flexion
against contracted quadriceps
Osgood-Schlatter disease is associated with what fracture?
Tibial tuberosity avulsion fractures
swelling and pain over the patella with point tenderness and
reduction in extension strength
(Large joint effusion or hemarthrosis)
Patella fracture
most common type of patella fracture?
“split” or transverse fracture in mid patella
>60%
comminuted patella fracture, also called?
“stellate” type - 25%
vertical patella fracture occurs what percent of the time?
15%
usually from medial facet due to lateral patella
osteochondral defect
Transverse (most common) patella fracture exerted by?
sudden forceful quad
contraction
Stellate fracture, usually from
direct impact and burst
best view for Lateral patella dislocation and osteochondral defect?
Sunrise view
Patella fractures need to be differentiated from
multipartite patella
important to recognize because coexistent vascular
(popliteal artery) injury complications
Knee Joint or Femoral-Tibial dislocation
Knee dislocation are classified in relation of
Tibial displacement compared to
the Femur
5 types of Knee dislocations
- anterior (40%) often hyperextension injury
- posterior (30%) may be due to direct falls or MVA “dashboard” injury
- lateral (20%)
- rotatory (5%)
- medial (5%)
most commonly torn ligament of the knee
ACL
imaging required for diagnosis and management of ACL tear?
MR
potential radiographic signs of ACL tear
- anterior tibial translocation sign
- Segond fracture
- arcuate fracture
- joint effusion
indicates avulsion of fibular attachment of biceps femoris and
lateral collateral ligament.
Arcuate sign
High suspicion for ACL tear and potential posterolateral
instability and failed ACL reconstruction
Arcuate sign
Acute ACL tears typically occur in the what portion of the ligament?
middle portion
Normal ACL angle should be aligned along femoral condyles known as the
Blumensaat’s line
O’Donogheu’s triad is typically due to
pivot shift and srong valgus
force
O’Donogheu’s triad
1) ACL tear
2) MCL tears and
3) tear of the medial meniscus (can be bucket handle tear)
m/c type of meniscal tear
horizontal or cleavage tear
Meniscal tears are best evaluated with
MRI
the meniscus that is torn much more frequently due to its
fixed attachment to corresponding tibial plateau
Posterior horn of medial meniscus
Acute meniscal tears that only involve the ______ of the outer fibres can be
managed conservatively or heal on their own
red zone
inversion stress is the most common cause of ankle injuries for 2
anatomic reasons
1) medial malleolus is shorter than the lateral malleolus
2) deltoid ligament is stronger than the lateral ligaments.
commonly associated with distal fibular fractures and are unstable
posterior malleolar fractures
classification of lateral malleolar fractures
Weber ankle fracture classification
Clinical diagnosis of suspected ankle fractures and the need for radiographic
examination can be successfully determined by applying the Ottawa Ankle
Rule
Ottawa Ankle
Rule
Weber __ : below syndesmosis
A
Weber __ at the level of
syndesmosis
B
Weber __ above syndesmosis
C
Lateral malleolus/distal fibula
fracture above syndesmosis is stable or unstable?
unstable
Lateral malleolus/distal fibula
fracture above syndesmosis is also referred to as?
Pott’s fracture
6cm above lateral malleolus
is combination of oblique or spiral fracture of the
proximal fibula and unstable ankle injury
Maisonneuve fracture (high ankle sprain)
Manifests by widening of the ankle joint due to distal tibiofibular syndesmosis
and/or deltoid ligament disruption
(sometimes fracture of the medial
malleolus)
Maisonneuve fracture (high ankle sprain)
Maisonneuve fracture is considered Weber __
C
positive squeeze test can indicate fracture or
high ankle sprain
Fracture of both lateral (fibula) and medial (tibial) malleolus and considered to
be unstable due to frequent disruption of distal tibiofibular syndesmosis and
sometimes deltoid ligament
Bimalleolar ankle fractures
transverse fracture through tibial
malleolus and oblique or spiral fracture through distal fibular
Bimalleolar ankle fractures
Bimalleolar fractures of this type may be described by some as
Dupuytren
fracture
Associated deltoid ligament
disruption and lateral dislocation
of the talus may exist
Bimalleolar fractures
Three-part (Trimalleolar) fracture of the ankle
involves what three structures?
- medial malleolus
- posterior aspect of the tibial plafond
(referred to as the posterior malleolus) - lateral malleolus
Triplanar fractures primarily
occur in ______ patients
younger
Results from an abduction-external rotation mechanism when anterior tibiofibular
ligament avulses the anterolateral corner of the distal tibial epiphysis
Tillaux fracture
Tillaux fracture requires an open physis and considered a Salter-Harris __
injury of ______
3, distal tibia
represents an anterolateral distal tibial epiphysis avulsion
Tillaux fracture
Tillaux avulsion fracture is rarely seen in adults because
the ligament gives out before avulsion
undisplaced spiral fractures usually of the tibia in toddlers either due to fall or when the leg is stuck in between the wooden spacing of the crib/cot
Toddler fractures
usually spiral and undisplaced
Occasionally in toddler fractures both tibia and fibula are fractured, referred by some as
Both Bones
fracture
Occasionally spiral or comminuted oblique tib & fib fractures occur as
Ski-boot or
Boot-top fractures
most frequently fractured foot
bones
calcaneus and talus
Most commonly fractured tarsal bone
calcaneus (60%)
Calcaneal fractures can be classified as…
- Extra-articular:
25-30% - Intra-articular:
70-75%
calcaneal tuberosity avulsion fracture, calcaneal w/o
talocalcaneonavicular (subtalar) extension
Extra-articular
Lover’s/Don Juan/Casanova fracture of which 10% can be associated with the TL fracture
Intra-articular
If bilateral calcaneal fractures are seen, then
the spine should be evaluated (xrays
and CT scanning)
Angle between two tangent lines drawn across the anterior and posterior
borders of calcaneus on the lateral view
Bohler’s angle
is less than 20- degrees it indicates a calcaneal fracture
Bohler’s angle less than ___ degrees it indicates a calcaneal fracture
20
a significant finding that should prompt active search for
fracture.
marked opacification of Kagar’s fat pad
Overuse injury seen in athletes, especially with running and aerobics, and
military recruits
Calcaneal Stress Fracture
Stress fractures in general may take how long to appear on conventional radiographs?
7-14 days
key radiographic feature of calcaneal stress fracture?
vertically oriented zone of increased density on lateral radiograph
that is perpendicular to the trabecular lines
considered most sensitive and specific imaging of stress fractures of the
lower extremity
MRI
Radiographic evaluation of a talur fracture must include what views?
DP, Oblique and lateral ankle/foot
views
Fractures of the talus can be divided into 3 main regions:
Body, neck, and head
extend through the thinnest portion of the talus, just
proximal to the talar head
Talar neck fractures
Common types of talus fracture are
avulsion fractures or vertical fractures
talur avulsions are typically due to
twisting foot injuries
Hawkins talus fracture classification
type I
non displaced fracture
Hawkins talus fracture classification
type II:
displaced fracture with subluxation or dislocation of the subtalar joint and
a normal ankle joint
Hawkins talus fracture classification
type IIl
displaced fracture with body of talus dislocated from both subtalar and
ankle joint
Talar neck fractures may be complicated with the risk of
avascular
necrosis (AVN)
AVN risk increases with increase in complexity
type I fractures has 0%–15% risk
type II fractures have 20%–50% risk
type III fractures approach 100% risk
The most common mechanism of potentially significant talar neck fractures is a
dorsally directed force on a braced foot
(such as in head-on motor vehicle
accidents when foot is pressing on the breaks)
Talar neck and to some degree talar body fractures were once known as
“Aviator’s astragalus fractures or Aviator’s fractures”
describes subchondral lucency/osteopenia line of the talar dome
that occurs secondary to subchondral atrophy 6-8 weeks after a talar neck fracture
Hawkins sign
Hawkins sign indicates that there is sufficient _______ in the talus
vascularity
Osteochondral injuries may be complicated by
early/secondary advanced DJD
can mimic a lateral ankle sprain
Lateral talar process fractures aka “snowboarder” fractures
Lateral talar process (“snowboarder”) fractures occur when the foot is
dorsiflexed and inverted
As many as ____ of lateral talar process fractures are missed on radiographs
40-50%
Posterior talar process fractures may involve
medial or lateral tubercle of the
posterior process of talus
Posterior talar process fractures are caused by
inversion
Unfused ossification center of the lateral tubercle forms the
os trigonum
Shepherd fracture is Injury of the
lateral tubercle
Cedell fracture is injury to the
is uncommon and is
caused by forced dorsiflexion and pronation
medial tubercle
Injury to the medial tubercle (Cedell fracture) is caused by
forced dorsiflexion and pronation
Injury to the medial tubercle (Cedell fracture) is treated using a
Short leg cast or ankle brace until signs of union appear
main DDx of posterolateral talar process fracture
Os trigonum
most common type
of dislocation involving the foot
Lisfranc fracture/dislocations
mechanism of Lisfranc fracture/dislocations include
direct crush injury, or an indirect load
onto a plantar flexed foot
the two types of Lisfranc fracture-dislocation are?
Homolateral and
Divergent
lateral displacement of the 1st to 5th metatarsals, or of 2nd to 5th metatarsals where the 1st MTP joint remains aligned
Homolateral
lateral dislocation of the 2nd to 5th metatarsals with medial
dislocation of the 1st metatarsal
Divergent
fracture/dislocation of the mid-tarsal joint of the foot, i.e. talonavicular and calcaneocuboid joints
Chopart injury
Chopart injury the commonly fractured bones are the
calcaneus cuboid and navicular
In chopart injury the foot is usually dislocated
medially and superiorly
most common stress fractures
2nd and 3rd metatarsal (march fracture)
occur at the base of the fifth metatarsal
Jones fractures
Dance Fx
Jones fractures occur at the metadiaphyseal
junction with OUT
distal or intra-articular extension
Jones fractures occur as a result of significant ______ force to the forefoot with
the ankle in __________
adduction, plantar flexion
fracture located approximately 2 cm (1.5-3 cm)
from the tip of the 5th metatarsal
Jones fracture
Jones fractures are prone to
non-union
with rates as high as 30-50%
non-union Jones fractures usually take ___ months heal
2
distal horizontal fracture line w/o
intra-articular extension
Jones Fx
one of the more common
foot avulsion injuries
pseudo-Jones fracture
Over 90 % of fractures of the base of the 5th metatarsal are?
pseudo-Jones fracture
pseudo-Jones fracture is occasionally
referred to as a
“tennis fracture“
pseudo-Jones fracture is caused by insertion of peroneus brevis and forcible
inversion of the foot in plantar flexion
tip of the proximal 5th metatarsal, oriented mostly transversely
pseudo-Jones fracture
Toe fractures most frequently are caused by a
crushing injury or axial force such
as stubbing a toe (Bedroom fracture)
Most children with fractures of the physis should be referred, but children with
selected nondisplaced Salter-Harris types I and II fractures may be treated by
family physicians
considered an open fracture and may carry
risk of osteomyelitis
Toe fractures involving the nail
Stable toe fractures can be treated with
Buddy taping
