Knee Flashcards
What may predispose to early OA in the knee?
previous meniscal tears
ligament injuries
malalignment eg genu varum/valgum
what is a high tibial osteotomy
may be helpful in treating patients with medial OA - OSTEOTOMY OF THE PROXIMAL TIBIA
When do meniscal tears classicaly occur
twisting force on a loaded knee
they can also occur due to degeneration of the menisci
What is the clinical picture of a meniscal tear
localised pain in a specific knee compartment
effusion
catching or locking of the joint
haemarthrosis within an hour of the injury
rotator instablility with the knee giving way
What do valgus stess injuries usually cause?
Tear the MCL
damage ACL
risking lateral tibial plateau fracture
When would a PCL rupture occur
a direct blow to the anterior tibua in a flexed knee (motercycle crash) or hyperextension
varus stress
What injuries can varus stress cause
LCL and PCL
Which menisci tears more commonly
the medial meniscus- it is more fixed than the lateral
What is a bucket handle tear
a large longitudinal tear where a large meniscal fragment is able to flip out of its normal position and displace anteriorly or into the intercondylar notch where the knee lock and is unable to fully extend
Why are meniscal tears difficult to heal
the meniscus only has an arterial blood supply in it outer third
When should a meniscal repair be considered
in younger patients with a fresh longitudinal tear involving the outer thirs of the meniscus
When may a partial menisectomy be beneficial
in patients who have pain that does not settle for thee months
In what group of patients Is menisecotmy not beneficial
knees with arthritis changes on x ray and MRI
What test can be used to determine if there has been an ACL rupture
Lachmans and Anterior drawer test = excessive translation of the tibia
Who is a candidate for ACL replacement surgery
professional sportsmen/women
those who’s knee gives way on sedentary activities
Where is the tendon graft for an ACL replacement usually from?
patellar tendon, semitendinosis and gracilis
How are acute MCL tears usually treated
hinged knee brace
How can chronic MCL instability be treated
tightening (advancement) or reconstruction with tendon graft
How are LCL ruptures usually treated
surgically with either early repair or late reconstruction with tendon graft
How are PCLs usually treated
Cadaveric Achilles tendon allograft
Which age group do patellar tendon ruptures tend to occur in
younger people (less than 40)
What age group does the quadriceps tendon tend to rupture?
Older people (over forty)
What are the predisposing factors to an extensor mechanism rupture in the knee
tendonitis history steroids diabetes RA renal failure (chronic)
Which antibiotic can cause tendonitis
Quinolone (ciprofloxin)
Which test determines if the extensor mechanism is intact
straight leg raise
What does a high patella signify
patellar tendon rupture
what does a low patella signify
quads rupture
What causes patellofemoral dysfunction
the pull of the quadriceps muscle can pull the patella slightly laterally- excess lateral force can cause anterior knee pain
What predisposes to anterior knee pain
gender (girls)
hypermobility
genu valgum
femoral neck anteversion
What are the symptoms of anterior knee pain
worse going down hill
grinding or clicking
pseudolocking
Where does the patella usually dislocate
laterally
What predisposes to patellar dislocation
ligamentous laxity females shallow trochlear groove genu valgum femoral neck anteversion patella alta (high riding patella)
What happens when the patella dislocated
medial patellofemoral ligament tears
osteochondral fracture may occur
lipo haemarthrosis
