The Knee Flashcards
How frequently should a person with a mild injury ice?
4 times a day for 15 minutes
What is the clinical presentation of someone with a patellar fracture? What is the treatment for them?
Pain with flexion; keep them in full extension, allow them to weight bear
What is the classic mechanism of injury for MCL, MM, and ACL (Triad of O’Donohue)?
1) knee flexion PLUS 2) foot planted PLUS 3) lateral impact PLUS 4) rotation
What is the test for MCL stability?
Valgus stress test
What does a grade of 0 on valgus stress test represent?
if it is equal to the other knee, it means there is no significant laxity
What does a grade of 1+ on valgus stress test represent?
5 mm of medial joint space with FIRM (but abnormal) ENDPOINT
What does a grade of 2+ on valgus stress test represent?
10 mm of medial joint space with SOFT ENDPOINT
What does a grade of 3+ on valgus stress test represent?
15 mm with SOFT ENDPOINT
What does a grade of 4+ on valgus stress test represent?
20 mm, may have associated cruciate tear as well
What is the test for LCL stability?
Varus stress test (same classification as valgus)
What is the most important structure for knee stability?
ACL
What are the 3 primary mechanisms of injury for ACL?
Planting and cutting, straight knee standing, and one-step stop with hyperextension
What is a/w 50% of ACLs?
Meniscal tears
How do you treat someone with an ACL tear conservatively?
immobilization and NSAIDs
What population is at highest risk for ACL sprain?
Women athletes in sports like soccer and basketball
What does Lachman’s test screen for? How?
ACL tear, tests anterior displacement of tibia vs. femur
What is the alternate Lachman’s test useful for?
Patients with muscles that prohibit a solid grasp of the femur with one hand
What is the biggest downside to using the anterior drawer test?
false negatives are elicited by swelling
Which meniscus is more susceptible to injury? Why?
Medial; greater forces and less mobile structure than lateral
What is the McMurray test used to check for and how?
Meniscal tears, one thumb on MM and one hand rotating the lower limb.
Pain with medial rotation on McM test indicates
lateral meniscal tear
Pain with lateral rotation on McM indicates
medial meniscal tear
What is the most common knee complaint in primary care?
Chondromalacia, or patellofemoral syndrome
What causes patellofemoral syndrome?
imbalance of quad strength (lateral>medial), recurrent patellar subluxation
What is the pain of patellofemoral syndrome described as?
Anterior pain under the patella, worse with stairs and after extended sitting. Usually with crepitus, popping, and instability
What component of the visit is most helpful in diagnosing chondromalacia?
History
How do you reproduce pain in extremities with patellofemoral syndrome?
knee in slight flexion and gently press patella and contract quads
Treatment for patellofemoral syndrome
strengthen quads, esp medial
what are clinical manifestations of Osgood-Schlater?
Local swelling and tenderness, worse with jumping +/- radiograph due to pre-ossification stages
What is Osgood-Schlatter? How is it caused?
Partial avulsion of tibial tuberosity; repetitive stress on immature bone
What is the tx for Osgood-Schlatter?
avoid strenuous exercise and jumping sports, +/- brace, usually self resolve in 1-2 years, NSAIDs are usually effective
What is the biggest differential b/w Osgood-Schlatter and patellar tendonitis?
age of onset, +/- TT avulsion
What can exacerbate patellar tendonitis symptoms?
excessive foot pronation and running hills
What is the treatment for patellar tendonitis?
NSAIDs, ice, brace, etc (nonsurgical, no steroids)
What direction does patellar dislocation usually occur?
Laterally b/c of size of vastus lateralis
How do you distinguish b/2 patellar fracture and bipartate patella?
Fx appears with sharper edges
