sm test KNEE injuries

Know MOI, s/s, Tx

Which sprain injury is considered the most serious ligament injury in the knee

ACL

how does the ACL run

 runs from the anterior tibia to the posterior femur

what does the ACl prevent

anterior translation of the tibia in relation to the femur

what does the ACL stabilize

the tibia against excessive internal rotation 

what does the PCL attach from

the posterior tibia to the anterior femur 

the PCLs purpose is

• Prevent hyperextension of knee 

• Prevent posterior translation of the tibia 

what does the MCL attach

medial epicondyle to the medial tibial plateau 

what does the MCL look like

it’s a wide and flat ligament

what is the MCLs purpose

• Protect against valgus force 

• Protect against external rotation 

Which ligament is smaller, MCL or LCL

LCL

Where does the LCL attach from

lateral epicondyle to the fibular head 

what does the LCL protect

the knee against varus forces 

ACL moi

External rotation of the tibia with the knee in a valgus position 

Cutting in the same direction as a planted foot

which sprain is “Cutting in the same direction as a planted foot”

ACL

ACL signs and symptoms

• Feeling and hearing a “pop”

• Immediate pain 

• Immediate laxity/disability 

• Rapid swelling 

• Feeling unstable 

MCl moi

• Direct blow from the lateral side (valgus force)

• External rotation of the tibia 

which sprains has External rotation of the tibia 

mcl

which knee sprain is more common, LCL or MCL

MCL

MCL s/s

• Depends on severity of sprain

• Grade 1

  • Mild pain over MCL, minor stiffness, stable knee

• Grade 2

  • Moderate swelling, loss of ROM, mild instability 

• Grade 3

  • Moderate swelling, immediate pain, loss of stability

PCL moi

A fall with the full weight on anterior aspect of the the bent knee with the ankle in plantar flexion

PCL s/s

• Feeling a “pop” in the back of the knee

• Tenderness in the back of the knee

• Laxity during posterior sag test 

• Instability during weight bearing

LCL moi

•  Direct blow from the medial side (varus force) and the tibia is internally rotated

what other injury can an LCL sprain be accompanied by

an avulsion fracture of the femur or tibia 

LCL s/s

• Pain and tenderness over LCL 

• Swelling over the LCL 

• Some joint laxity 

• The greatest pain is with grade 1 and grade 2 sprain

Meniscus moi

Rotation while weight bearing 

what injury is “Cutting while running” 

meniscus

what kind of meniscus is most likely to be injured

medial

Meniscus s/s

• Moderate/mild swelling 

• Pain along the joint line 

• Intermittent locking and giving away of the knee 

• Pain when squatting 

• Pain when going up or down stairs

what is plica

folds in the synovial capsule that did not close during development

what amount of the population does knee plica occur in

20%

what type of plica is most subject to injury, and what is the plica like

mediopatellar plica

• the plica becomes thick and fibrous

what knee injury is knee plica syndrome commonly associated with

chondromalacia

Knee Plica s/s

• Patient usually has a history of knee trauma 

• Episodes of painful pseudolocking (patient feels like the knee is locked/“needs to pop”) after sitting for long periods of time

• Knee snapping may be felt or heard during knee flexion 

• Pain going up or down stairs 

• NO SWELLING OR LAXITY

what is patella dislocation

total displacement 

patella subluxation/dislocation occurs when

the patella slides out of the femoral groove

what is Patella Subluxation

a partial displacement 

patella Subluxation signs and symptoms

• Pain and swelling 

• Tenderness over medial border 

• Instability 

patella dislocation signs and symptoms

• Obvious deformity 

• Loss of function 

• Pain 

what is osgood- schlatters

apophysitis of the tibial tuberosity

• Inflammation at the attachment of the patella tendon to the tibial tuberosity 

what is osgood- schlatter caused by

tension placed on the tibial tuberosity from the patella tendon 

what age does osgood- schlatter occur and what age does it resolve

adolescence

age 18

Osgood-Schlatter Signs and Symptoms

• Enlargement of the tibial tuberosity 

• Severe pain when kneeling, jumping, and running 

• Point tenderness over the tibial tuberosity

what injury is known as the Dashboard injury

PCL