Lower Extremity Flashcards
athlete with anterior knee pain
patellofemoral arthralgia
patellar tracking disorder
elderly patient with knee pain
osteoarthritis
usually affects the medial portion of the joint (weight bearing)
young athlete with tibial tuberosity pain
osgood schaltet disease
complaint of instability
chronic ACL damage
complaint of painful locking
meniscus tear
hyperextension
ACL tear
patellar dislocation
hyperflexion
PCL tear and/or associated ACL tear
sudden deceleration
ACL tear
valgus force
medial collateral ligament tear
valgus force with rotation
ACL
MCL
Menisci
blow to flexed knee
contusion
patellar fracture
PCL tear
ACL Testing
challenging posterior to anterior stability of the knee
lachman’s test
anterior drawer test
pivot shift test
Meniscus Testing
compressive challenge
McMurrays test
Apley’s Compression and Distraction
Collateral Ligament Testing
Varus Stress Test
Valgus Stress Test
Patellofemoral Disorders
Compression
Stability
Tracking
Ottawa Knee Rules for Acute Trauma
patient over 55 years old
isolated tenderness at the patella
isolated tenderness of the fibula head
patient is unable to flex knee to 90 degrees
patient is unable to bear weight immediately after the injury or take four steps
Classic presentation of ACL tear
acute or chronic onset
Acute onset ACL tear
• sudden onset of pain following hyperextension maneuver,
sudden stopping or cutting, or contact injury with the knee being hit from the side
• may hear pop
• joint swelling appears quickly
• patient is unable to bear weight
Chronic presentation of ACL tear
Patient will have a past history of the acute onset type with a gradual resolution of joint swelling and pain, with the complaint usually being instability
O’Donaghue’s Triad
aka unhappy triad
ACL
Medial Meniscus
MCL
What type of fracture is associated with ACL tear?
Segond’s Fx or potential tibial spine fracture, or head of fibula
Segond’s Fx
type of avulsion fracture (soft tissue structures tearing off bits of their bony attachment) of the lateral tibial condyle of the knee, immediately beyond the surface which articulates with the femur
Mechanism of injury: internal rotation and varus stress which causes abnormal tension on the central portion of the lateral capsular ligament
ACL is most common injury with Segond’s Fx, other injury includes Medial Meniscus or Lateral Meniscus
First image with a knee injury is plain film, if Segond’s is found then do an MRI
Complete ACL Tear
focal discrete complete disruption of all visible fibers
Partial / Intrasubstance Tear
abnormal signal intensity within substance of ligament with some intact and some discontinuous fibers
What color should ligaments/tendons be on MRI
low signal (black) if damaged it will be a higher signal (gray)
Where does the ACL lie
The ACL lies in a plane 10-15 degrees externally rotated to the sagittal plan
Posterior Cruciate Injury
- knee pain following a blow to the front of his tibia with the knee in a flexed position or by forced hyper flexion
- less common than an ACL tear
- posterior drawer sign
- SAG sign
- X-ray reveals increased signal and thickening
Where does the PCL attach
attaches proximally on the internal aspect of the medial femoral condyle and runs distally to where it attaches to the posterior eminence of the tibia
Where does the ACL attach
It attaches proximally at the internal aspect of the lateral femoral condyle and runs distally to its broad attachment to the anterior tibia and the anterior aspect of the tibial spine
Where does the PCL lie
It lies in the sagittal place and can usually be seen in its entirety on a single sagittal MR slice
Where do avulsion fx mostly occur
they occur at the insertion of the ACL (most common) and PCL. Most commonly seen in adolescents.
