Lower Extremity Clinical Correlates Flashcards
What causes cauda equina syndrome? Why is it an emergency?
It’s rare, but caused by a large central herniation
It’s an emergnecy because it will knock out the spinal nerves at the level of the herniation and at all the levels below it
it will be permanent after about 6-8 hours
you get saddle anesthesia, bilateral leg weakness and bladder/bowel incontinence (plus back pain obviously)
WHere will trocanteric pain occur? Where will hip pain occur?
trochanteric pain will be in the lateral thigh. Hip pain is more in the groin area - sometimes the buttock
WHat is the primary concern with femoral neck fractures?
Depending on how back the fracture is/how displaced the fracture it, the blood supply to the femoral head may be at risk and you can end up getting avascular necrosis fo the head.
WHere does blood supply to the femoral head primarily come from?
from the medial circumflex arter that wraps around the neck and goes up to the head.
Displaced fractures of the femoral neck have a 40% risk of avascular necrosis. How do you treat this in an elderly patient. How do you treat this in a young adult.
For an elderly patient you just go in and put in a prosthesis right away.
For a young adult, you will always pin them because having their own joint intact will be better in the long run. IF they are one of the 40% that get the necrosis, you can go in later and do a prosthesis.
What sorts of meniscal tears do you repair and which do you take out?
It all depends on blood supply - if the tear is in an area with blood supply it will be able to heal, so you repair it. If there is poor blood supply, you should just take it out.
What two physical exam tests can you use to look for ACL tears?
the Lachman’s exam (flex to 20 degrees, stabilize the femur, and pull forward - anterior movement?)
THe anterior drawer - bend to 90 degrees and pull the leg forward like a drawer - anterior movement?)
What test can you use to look for a posterior cruciate tear?
the posterior drawer
WHere will pain occur in a medial collateral ligament tear?
What test should you use?
Pian will be on the femur - not the joint–because that’s where it tore.
Do a hinge test to see if the joint will open up.
SUrgery usually not needed - just a hinge brace
What causes Osgood-Schlatter syndrome?
You get tenderness and swelling at the site of the infrapatellar tendon insertion into the tibial tubercle.
There is tremendous force on the tubercle from the quads, so you get periossificaiton and inflammation aruond it.
What radiologic studies are best for stress fractures?
You won’t be able to see one on X-ray until it heals over about 3 weeks later
Use MRI or a bone scan to look acutely
How can you test for an achilles tendon tear?
Sweeze the gastrocnemius proximally and the foot should plantar flex.
if it doesn’t there’s a tear
you can also just feel a disformity in their calf
Posterior dislocation of the hip will cause what neurological issue?
You get injury to the sciatic nerve with foot drop.
What direction will the leg go in a posterior hip dislocation? In an anterior hip dislocation?
In a posterior, the let will be medially rotated
In an anterior, the leg will be laterall rotated and shortened.
What blood pressure in a compartment would warrant a fasciotomy for compartment syndrome?
over 30 mm Hg
What will happen if a comaprtment syndrome in the upper extremity isn’t treated?
Volkmann’s contracture
What are the “tension signs” that go along with radicular pain?
increased abdominal pressure and disc pressure:
positive straight leg raise and contralateral straight leg raise
pain with valsalva maneuver
pain with coughing
pain with straining at stool
What disc levels go with the patellar reflex?
What disc levels go with the achilles reflex?
patellar = L3-L4 (root L4)
achilles = L5-S1 (root S1)
Note that there isn’t a reflex that goes with root L5
Where will the sensation of pain be in compression of the following?
L4
L5
S1
L4 = medial leg and medial foot
L5 = lateral leg and dorsum of foot
S1 = Lateral foot
What part of the meniscus has blood supply (and is therefore repairable)?
the outer 1/4 to 1/3d
What is the primary concern with true knee dislocations?
damage to the vascular supply
Where are stress fractures of the lower extremity particularly common?
tibia
metatarsals
calcaneus
some in pelvis and femoral neck
Which is more common in an ankle sprain: inversion or eversion?
inverison 90%
eversion 10%
Which ligaments are injured in the following inversion ankle sprains?
Grade 1
grade 2
grade 3
How about in eversion ankle sprains?
grade 1 = ATF ligament
grade 2 = CF ligament
grade 3 = PTF ligament
eversion = deltoid
What will cause pain in the heel of the foot - particularly along the medial epicondyle?
plantar fasciitis
