knee Flashcards
is genu varum bow legged or knock kneed?
bow legged
what occurs at the posterolateral corner of the meniscus?
it is separated from the rest of the capsule by the popliteus tendon
which meniscus, lateral or medial, is more commonly injured?
medial
what two motions does the LCL restrain?
varus, lateral tibial rotation
when is the LCL most responsible for restraint of lateral gapping and why?
at 25 degrees of knee flexion, all posterior structures are on slack
when is the MCL most responsible for restraint of medial gapping and why?
at 25 degrees of knee flexion, open pack of the knee, other structures are on slack
why is the MCL able to heal easily?
rich blood supply
what forces does the posterolateral bundle of the ACL resist and during what degrees of knee flexion?
anterior at 0-20 degrees of knee flexion
what forces does the anteromedial bundle of the ACL resist and during what degrees of knee flexion?
anterior at 20-90 degrees of knee flexion
what is the most common cause of noncontact ACL injuries
deceleration with the knee in slight flexion coupled with medial or lateral tibial rotation
how many parts does the PCL have and what are they?
2, anterolateral and posteromedial
what part of the PCL is the most important and when is it tight?
anterolateral, tight in flexion
what two ligaments oppose medial forces?
PCL and MCL
can you selectively activate the VMO?
no it is innervated by the femoral nerve along with the rest of the quads so it is quite difficult to isolate
what is the difference in anterior shear forces at the knee during OKC vs CKC exercises.
OKC has high shear forces while CKC has low shear forces
what is a normal Q-angle for men?
10-15 degrees
what is a normal Q-angle for women?
15-20 degrees
what are the ottowa knee rules?
age >55, isolated tenderness of the patella, fibular head tenderness, inability to flex knee to 90 degrees, inability to bear weight after injury and in ER (need 4 steps)
what diff dx should you be aware of in someone who is between 8-17 years old, reproduced knee pain with a FABER test, loss of hip IR, and increased hip ER?
SCFE - Slipped capital femoral epiphysis
what population is the WOMAC used for? what score indicated a healthy knee?
OA of the knee, 0 is a healthy knee score
What population is the KOOS useful on? what score indicated a healthy knee?
higher activity folks, 100 is a healthy knee
what population is the IKDC-SF useful for?
everyone, broad population
what population is the Lysholm Knee Score useful for? What score indicated a healthy knee
after ligamentous and meniscal surgery, 100 is a healthy knee
What population is the KOS useful with? What score indicates a healthy knee?
useful with a broad audience, a higher score is a healthier knee
what population is the LEFs useful for and what score indicates a healthy knee?
broad audience, higher score is a healthier knee
on the fear avoidance beliefs questionnaire what does a higher score indicate?
higher fear avoidance
if someone has >5mm gapping on the valgus stress test, what other structures may be involved?
usually PCL and possibly ACL
how would you grade the sensitivity and specificity of the anterior drawer test on acute ACL injuries?
poor
how would you grade the sensitivity and specificity of the anterior drawer test on chronic ACL injuries?
pretty darn good
how can you use the posterior drawer test to dx a PL corner injury?
perform the test at 30 and 90 degrees of flexion, a positive test with have excessive posterior translation at 30 degrees of flexion
if someone has excessive posterior translation at 30 degrees but not at 90 degrees on the posterolateral drawer test what does that indicate?
a Posterolateral corner injury
how do you perform the prone external rotation test (dial test)
patient in prone, test tibial ER at 30 and 90 degrees of flexion
what is a positive test on the prone ER test (dial test)?
> 10 degrees of external rotation on the involved side
what if someone has >10 degrees of rotation on the dial test at 30 and 90 degrees of flexion?
possible PCL and posterolateral corner involvement
what three tests are used for meniscus?
mcmurray, apleys, joint line tenderness
what is a useful cluster for meniscus tears? (5 items)
hx of catching or locking, joint line tenderness, pain with forced hyperextension, pain with max knee passive knee flexion, pain or clicking with McMurrays
what percentage is considered normal in hop performance side to side?
80-85%
what knee dx have shown a positive response to taping?
PFP and OA
has bracing been shown to be beneficial in ACL patients?
no
what 4 criteria must someone meet to be eligible for conservative management of an ACL tear?
no more than 1 episode of giving way since injury, greater than 80% on the hop test, KOS ADL score >80%, and global rating score >60%
if an ACL and PCL are recon at the same time, which protocol do you follow?
PCL, the outcomes are worse and failure rates are higher
in a pt who is not skeletally mature what is normally done with an ACL rupture in terms of surgery and timing?
wait until the epiphyseal plates are closed
do most PCL injuries require surgery?
no
how long is RTP typically after a grade III PCL injury?
3 months
how long is RTP typically after a grade I and II PCL injury?
2-4 weeks
what are two things you have to be very cautious about after PCL surgery?
no flexion past 70 degrees initially as it stretches repair, no resisted knee flexion for 8 weeks as it causes posterior tibial translation
what will someone with a posterolateral corner injury complain of?
instability with cutting and pivoting
what exercises should be avoided after posterolateral corner recon and for how long?
isolated hamstring exercises, for 4 months due to posterior pull and translation
when is meniscal transplant contraindicated?
when a pt has varus or valgus malalignments, advanced OA, uncontrolled knee instability
what is the timeline to run after a meniscus transplant?
1 year
what is the long term outcome of mensicus transplant?
usually deterioration and further surgery
what is the strongest predictor of functional limitations in patients with knee OA?
quad weakness
are unloading braces useful in unicompartmental OA?
yes
after an osteotomy how long is weight bearing and resistance limited for?
4 weeks
how soon after a debridement or chondroplast can someone return to sport?
as early as 4 weeks
how soon after micro fracture can someone return to sport (both small and large)
4-6 months for small lesion, up to 8 months for large lesions
has patellar taping been shown to be helpful in treating PFP?
yes
does the direction of taping matter in PFP?
only kind of, tape in the direction of relief, not what you see anatomically
what is the site of irritation with Osgood-Schlatter disease?
tibial tubercle
what age do you normally see OSD occur?
10-15 y/o
what is the site or irritation with Sending -Larson-Johansson disease?
inferior pole of the patella
what age range do you normally see SLJ symptoms?
10-12 y/o
