Knee Injuries Flashcards
What is the most commonly injured knee ligament?
ACL
How can the ACL be injured?
Non-contact injuries are most common (e.g. sudden twisting, awkward landing)
Lateral blow to knee
Skiing
What are features of an ACL injury?
Sudden popping sound
Knee swelling immediately
Instability
Inability to weight-bear immediately
What are tests for ACL injury?
Anterior drawer test
Lachman’s test
How is anterior drawer test performed?
Pt supine with the knee at 90 degrees. One hand behind tibia and the other on thigh - thumb MUST be on the tibial tuberosity.
Tibia pulled forward to assess anterior tibial motion relative to the femur
Intact ACL should prevent forward movement.
How is Lachman’s test performed?
Variant of anterior drawer test - knee is at 20-30 degrees
Which is more reliable: ADT or Lachman’s?
Lachman’s test
How to differentiate an ACL injury from a meniscal tear?
Timing of swelling:
- ACL immediately swell due to haemarthrosis
- Meniscal tears swell over time
What is healing like of a ruptured ACL?
Poor healing
Mx of a ruptured ACL?
Intense physio or surgery
What is the mechanism of a ruptured posterior cruciate ligament?
Hyperextension injury (e.g. head-on car crash)
Results in tibia lying back on the femur
How can one test for a PCL rupture?
Posterior drawer test (paradoxical anterior drawer test)?
Tibia displaces posteriorly on application of a force
what soft tissue injury is a/w a medial tibial plateau fracture?
acl
what soft tissue injury is a/w a lateral tibial plateau fracture?
lateral meniscal tear
how are tibial fractures managed?
conservative - immobilisation in hinged knee brace for 8-12 weeks
displaced or open - surg fixation
