1. Orthopedics Board
Review
part 2: downstairs

2. MS/PGY1s
Name that dislocation and
describe how it happened.

3. Posterior Hip Dislocation
Accounts for 90% of hip
dislocations
Posteriorly directed
force applied to flexed
knee
PGY2s:
How quickly should you reduce this dislocation after
identifying it? Why?

4. Complications of Posterior Hip Dislocation
Reduce within 6 hours
Risk of femoral head
avascular necrosis
(AVN) increases as
delay to reduction
increases >6hrs
Up to 50% have
associated acetabulum
or femur fracture
Sciatic nerve injury radiopedia.org, Dr. Gagandeep Singh*
occurs in about 10%
PGY3s:
Name the radiographic view that helps you assess the
acetabulum.
How can you clinically assess for sciatic nerve injury?

5. The Judet view (45° oblique) is the best plain
film method for visualizing the acetabulum.
Posterior rim fractures commonly result from posterior dislocations
– can result in instability and accelerated osteoarthritis.

6. The sciatic nerve branches into the
common peroneal and the tibial
nerves
• Motor: dorsiflexors • Motor: plantarflexors
• Sensory: web space of • Sensory: sole of the
the great toe (this is foot
the deep peroneal
branch)
Blech… anatomy.
Thanks, Dr. tmi.

7. Turns out this stuff is also good to know if
you are considering compartment syndrome
after a tib-fib fracture
• Motor: dorsiflexors • Motor: plantarflexors
• Sensory: web space of • Sensory: sole of the foot
the great toe (this is the
deep fibular branch)
tibia
Deep peroneal
n. within the
anterior Tibial n. within
compartment the deep
posterior
compartment
Cross section of leg

8. Grandma has fallen and she can’t get
up.
(Really, you knew this had to be coming.)
For the next few slides:
MS/PGY1: Name the
fracture type.
PGY2: Traction or no
traction?
PGY3: You’ll get your
question when we get
there.

9. 1s: Name it.
2s: Traction?
3s: Low-energy fractures of this type are associated with
chronic use of which class of drugs?

10. Subtrochanteric femur
fractures
Traction is recommended
The atypical step-like fracture
pattern in this x-ray should make
you think of bisphosphonate-
associated fracture
If the mechanism doesn’t make
sense, also think of primary or
metastatic malignancy
May be complicated by 1-2 liter
blood loss from deep femoral
artery injury
Andrews, NA

11. Sadowski, et. al.
3s: What is the 6-month mortality associated with this
injury?

12. Reverse oblique
intertrochanteric femur fracture
Traction is recommended
Hip fractures have a 10-30% 6-month
mortality, mostly from infection or
pulmonary embolism
Can also be complicated by life-
threatening hemorrhage
The reverse intertroch fracture is
always unstable, and you should
manage it as cautiously as you would
this guy…

13. http://www.ihipfracture.com/*
3s: Give a major complication of this type of fracture.

14. Femoral neck fracture
Traction is contraindicated
AVN is a major complication
Patients with nondisplaced
femoral neck fractures may
be ambulatory
CT or MRI may be required if
clinical suspicion is high and
radiographs are negative
The Shenton line is used to
assess AP films for this
fracture…

15. Shenton line
http://www.ihipfracture.com/femoral-neck-fractures-in-a-young-patient/

16. MS/PGY1s:
Name the soft tissue
structures that are damaged
here.
PGY2s: What vascular injury
is associated with this
dislocation?
PGY3s: What nerve injury is
associated with this
dislocation?

17. Tibiofemoral (knee) dislocation
Anticipate damage to ACL, PCL, MCL, LCL, medial and
lateral menisci, and synovial capsule
Because this injury is grossly unstable, spontaneous
reduction occurs in up to 50% of cases
Popliteal artery injury in up to 1/3 of cases
If undetected may result in ischemia and amputation
If no hard signs of vascular injury, consider admission for
serial exams
Common peroneal nerve injury is also common

18. The“hard signs”
The Hard Signs
Hemorrhage
Expanding hematoma
Thrill
Bruit
Ischemia (5 P’s)

19. MS/PGY1s: This 28yo patient came out from the bottom of a
scrum pile with this swollen, painful knee. He’s worried that
he “tore his other ACL.” How will you assess for ACL injury?

20. About that ACL
Anterior Drawer test Lachman test
Knee is flexed to 90° Knee is flexed to 30°
Most sensitive ( 84%)
• Mechanism of injury is typically deceleration or hyperextension
from a blow to the anterior knee
• Patients often report feeling a “pop” which is followed by rapid
and impressive swelling
70% of patients with acute, traumatic hemarthrosis
have an ACL injury

21. Aside from the effusion, the x-ray is negative for this patient.
You decide to perform arthrocentesis to improve mobility and
reduce pain. When you empty the bloody aspirate into a
basin, round, shiny globs coalesce on the surface.
PGY2s: What is that stuff? What caused it?

22. Lipohemarthrosis
indicates occult fracture
Fat globules escape to the synovial space from fractured
bone
In order of likelihood, suspect
Tibial plateau fracture
Lateral plateau fractures often associated with ACL and MCL
injuries
Mechanism: blow to lateral knee
Tibial spine avulsion
Anterior attachment point for ACL
More common in peds who have tougher ligaments than bones
Femoral condyle fracture
Uncommon, but associated with popliteal artery and fibular
nerve injury

23. Sometimes you can see
lipohemarthrosis on plain film
• fat
* blood
Radrounds.com

24. Swollen knee – can’t walk
Suppose on your initial history, the patient tells you he has
been unable to walk since the injury occurred. He is unable
to extend his knee on your exam.
PGY3s: Now what is your differential
diagnosis? How can exam/work-up help you
differentiate these injuries?

25. Knee extensor injuries
Patellar tendon rupture
Hip flexion intact, knee extension absent or very weak
May see patella alta on x-ray
Patients usually younger than 40yo
Quadriceps tendon rupture
Both hip flexion and knee extension disrupted
Patients usually older than 40yo
Patella fracture
Transverse fractures may disrupt extensor function
Mechanism is the same for all injuries: forceful quadriceps
contraction or a direct blow to the flexed knee

26. What would the Canadians do?
Your patient presents after an
unfortunate mishap involving a
cute new pair of heels. He
has not been able to walk
since the mishap because of
pain. He is swollen and
tender over both malleolli on
exam.
MS/PGY1s: Review the
Ottawa ankle rules and tell me
if he should get an x-ray.

27. Ottawa Ankle Rule
Get the x-ray if the patient is 18-55yo, has any malleolar
pain, and any one of these:
1. Bony tenderness at tip or distal 6cm of posterior edge of
the medial malleolus
2. Bony tenderness at tip or distal 6cm of posterior edge of
the lateral malleolus
3. Inability to bear weight for 4 steps immediately and in the
ED
This decision rule is 97-100% sensitive for radiographically
detectable ankle injuries.

28. PGY2s: Interpret, please.
Identify the talus and medial, lateral, and posterior malleoli.

29. This guy seemed to have an unusual amount of pain
when you squeezed his calf, so you get stress views.
Now what do you see?

30. Syndesmotic disruption
When caused by eversion
mechanism, indicates medial
structural disruption. This
means medial malleolus
fracture or deltoid ligament
tear.
PGY3s: What x-ray view will Normal values (mortise view):
you order now? What is the Tibiofibular clear space < 10mm
eponym of the fracture you are Tibiofibular overlap > 5mm
trying to exclude?

31. Maisonneuve fracture
oblique proximal fibula
fracture AND
medial malleolus fracture
OR
deltoid ligament tear
Long leg splint, non-
weightbearing, and timely ortho f/u

32. The tibiofibular
syndesmosis is Inversion is limited by:
important for lateral malleolus
rotational stability. tibia and
anteior talofibular
ligament (ATFL)
and
Eversion is limited by: calaneofibular ligament
medial malleolus (CFL)
and talus
deltoid ligament(s)
calcaneus
Most commonly injured ankle ligament: ATFL
The plafond is the articular surface of the distal tibia.
A pilon fracture is a high-energy comminuted distal tib/fib fracture
caused by axial force to the plafond.

33. Your next Flex patient…
Amidst a post-olympics fervor, a middle-aged accountant
was skoolin’ some punks in b-ball at the Y when he injured
his heel. He was coming down off a jump shot when he
thinks someone kicked the back of his heel. He felt a pop
back there.
On your exam, he is tender on the back of his heel and
seems weak with plantar flexion.
MS/PGY1: What has he injured?
PGY2: Name and describe the clinical exam maneuver you’ll
do to verify your diagnosis.
PGY3s: Name two classes of medications that increase risk
for this type of injury.

34. Achilles tendon rupture
 Thompson test attempts to induce plantar flexion by
squeezing the gastrocnemius
Negative (Achilles intact) Positive (complete Achilles
rupture)
 Corticosteroids and fluoroquinolones may cause
tendinopathies

35. True story…
22yo F ~20 weeks by LMP, intoxicated and high, is brought
to the ED by JSO after she reportedly jumped from a second
story window. Swelling and ecchymoses of the feet prompt
this x-ray.
MS/PGY1: Where’s the
fracture?
PGY2: What associated
injuries must you
consider?
PGY3: Name the angle
you can measure on x-ray
to look for subtle fractures
of this type and describe
radiology.med.sc.edu how to measure it.

36. Calcaneus fracture
Most commonly caused by fall/jump from height and
landing on feet
10% have lumbar spine fractures
*
Boehler’s angle is normally 20-40° <20° indicates
fracture

37. How to read a lateral foot x-ray
Navicular – most commonly
fractured bone of midfoot
If this doesn’t look
like the profile for a
bunny slope,
think Lisfranc and
look at other views better
remember
Boehler
Toe stuff
5th metatarsal head –
(pseudo)Jones fracture?

38. What to do with the AP view
Most common If the line between the
site of stress 1st and 2nd metatarsals
fractures in the and cuboids is wide
foot: 2nd and 3rd or you see a fracture
metatarsals at the base of the 2nd
metatarsal, think
Lisfranc dislocation
Jones fracture?
navicular
Intact and snug
talus with the talus?

39. The oblique view
If the line between the 2nd
and 3rd metatarsals and
cuboids is disrupted or
wide, think
Lisfranc dislocation
talus
calcaneu
s

40. Let’s practice. MS/PGY1s: Where’s the injury?
Radiopaedia.org (Dr. Frank Gailliard)*

41. PGY2s: Give at least one eponym for this fracture.
Radiopaedia.org (Dr. Frank Gailliard)
PGY3s: Which tendon is responsible for this injury?

42. Pseudo-Jones or Dancer
fracture
Avulsion of base of 5th
metatarsal
Attachment point of
peroneus brevis
Inversion mechanism
Hard-soled shoe, WBAT

43. Jones fracture
Transverse metaphyseal-
diaphyseal junction
fracture of 5th metatarsal
Inversion mechanism
High incidence of nonunion
NWB, ortho f/u for casting
or surgery within 48 hours
Radiopaedia.org (Dr. Frank Gailliard)

44. MS/PGY1s: Anything seem amiss here?

45. Here’s the AP from the same patient…

46. Lisfranc fracture-dislocation
PGY2s: How much
displacement is allowed
between the 1st and 2nd
metatarsal base?
PGY3s: Discuss
management for these
injuries.

47. Lisfranc dislocation
1mm or greater gap between the 1st and 2nd metatarsal
bases indicates unstable injury
Require ortho consult for immediate reduction of
dislocation
Mechanism: direct trauma or hyperdorsiflexion
Suspect when exam demonstrates pain with torsion of
midfoot or plantar ecchymosis
Bilateral weightbearing AP views or CT aid diagnosis
Misdiagnosis rate of 20%
Complicated acutely by compartment syndrome

48. Final challenge
Radiopaedia.org (Dr. Frank Gailliard)
MS/PGY1s: Anything look weird here?

49. There’s something wonky
about the navicular bone…
PGY2s and 3s:
What is this injury
called? What’s your
management plan?
Radiopaedia.org (Dr. Frank Gailliard)

50. Subtalar dislocation
Mechanism: significant torsional force
Usually presents with deformity, but dramatic swelling can
conceal the dislocation
Always unstable
Requires immediate reduction and rapid ortho f/u

51. Tintinalli, 7th edition
Harwood-Nuss, 4th edition
Koval & Zuckerman, Handbook of Fractures, 3rd edition
Wheless’ Textbook of Orthopedics, whelessonline.com
Andrews, NA. Atypical subtrochanteric and femoral shaft fractures in bisphosphonate
users: Five years and counting, yet still too many unanswered questions. IBMS
BoneKEy (2010) 7, 296–303 (2010)
Sadowski C, Lübbeke A, Saudan M, Riand N, Stern R, Hoffmeyer P. Treatment of
Reverse Oblique and Transverse Intertrochanteric Fractures with Use of an
Intramedullary Nail or a 95° Screw-Plate : A Prospective, Randomized Study. J Bone
Joint Surg Am, 2002 Mar 01;84(3):372-381
Christos SC, Chiampas G, Offman R, and Rifenburg R. Ultrasound-Guided Three-In-
One Nerve Block for Femur Fractures. West J Emerg Med. 2010 September; 11(4):
310–313.
Good sources for radiographs used in this lecture
LearningRadiology.com
Radiopaedia.org
Radrounds.om
*Images used with permission under Creative Commons licensing
Unlabeled radiographs from our ED