ACL + PCL injury Flashcards
Describe the position of the ACL?
Attaches anteriorly ( + medially ) on the tibial intercondylar area and then passes posteriorly to attach on the lateral aspect of the femur
(PAMs APpLes)
What does ACL stand for?
Anterior cruciate ligament
What is the role of the ACL?
Stops the tibia from sliding forward in relation to the femur
What is the common mechanism behind an ACL injury?
Twisting injury - normally in sports when there is a quick change in direction
How does an ACL injury commonly present?
Popping sound or sensation Sudden onset pain Swelling Instability of joint - tibia can more anteriorly below the femur Unable to weight bear
Over time muscle weakness develops
What special tests can be used for a suspected ACL injury?
Anterior drawer test
Lachman test
Describe the anterior drawer test
Patient lying down with hip flexed to 45 and knee at 90 degrees with foot flat on bed.
Sit on patients toes to stabilise foot.
Hold leg below the knee and pull the proximal tibia anteriorly.
With ACL injury = tibia can move an excessive distance anteriorly
What investigations are normally carried out for ACL injuries?
MRI scan (first line) Arthroscopy (gold standard)
How is an ACL injury managed?
RICE - rest, ice, compression, elevation
Analgesia - normally NSAIDs
Crutches + braces may be useful
Physiotherapy
Arthroscopic surgery - to reconstruct ligament. Normally in active + young patients.
How is an ACL tear repaired surgically?
Arthroscopic surgery
A new ligament is formed using a graft of tendon from another place, normally the
- hamstring tendon
- quadriceps tendon
Describe the position of the PCL
Attaches posteriorly (+ laterally) on the tibial intercondylar area and then passes anteriorly to attach on the medial aspect of the femur
(PAMs APpLes)
What is the role of the PCL?
Stability of the knee joint
Prevents hyperflexion
What is the common mechanism for a PCL injury?
High energy trauma - such as road accidents
How does a PCL tear present and what is seen on examination?
Immediate posterior knee pain
Instability of joint
Swelling
Positive posterior drawer test
