ACL-R Flashcards
What are ACL-R outcomes in relation to surgical management?
Poor, only 50% of athletes regain pre-injury level and re-injury risk is high after return.
What is the reinjury risk following ACL-R?
Roughly 6x greater than those who didn’t suffer ACL injury.
What is the function of the ACL?
Prevents anterior translation of the tibia and rotational loads.
What can cause ACL injury?
What is likely mechanism of injury?
~70% Non-Contact (Pivoting, valgus force + IR)
~ 30% Traumatic (Direct blow e.g. tackle or RTC)
What relationship exists between gender and ACL injury?
Women are 3x more likely to injure their ACL.
This is due to their wider pelvis, increased Q-angle, more laxity of ligaments and a smaller intercondylar notch.
What are the grades of ACL Injury?
Grade 1 - no tear, tender and swollen, nil instability or laxity.
Grade 2 - partially torn, some loss of function, some instability, increased translation but firm end range, painful Lachman’s / Anterior Drawer.
Grade 3 - Complete rupture, tender and swollen, increased translation with no end range stop, minimal knee control, positive pivot shift test.
What grade of ACL tear does this sound like:
“tender and swollen, nil instability or laxity, negative Lachman’s / Anterior Drawer.”
Grade 1
What associated injuries often occur alongside an ACL injury?
“Unhappy triad”: Meniscal / MCL
Bone Contusion / Microfracture (Traumatic)
Chondral Injury (Traumatic)
Tibial Plateau Fracture
PLC Injury
Baker’s Cyst
What is the Clinical Presentation of an ACL Injury?
MOI: Cutting / Pivoting maneouvre or single leg standing, landing, jumping.
Audible ‘pop’ during time of injury
Feeling of instability (later masked by swelling).
Episodes of giving way during twisting.
Extremely painful, swollen with restricted movement (especially extension).
TOP medial joint line may indicate associated cartilage injury.
What grade ACL tear does this sound like?
“some loss of function, some instability, increased translation but firm end range, painful Lachman’s / Anterior Drawer.”
Grade 2
Injuries to the ACL rarely occur in isolation, often the “unhappy triad” is affected. What structures make up the “unhappy triad”?
ACL, MCL & (Medial) Meniscus
Lateral Meniscus lesions are present but at a much lower rate than medial meniscus.
What grade ACL tear does this sound like?
“tender and swollen, increased translation with no end range stop, minimal knee control, positive pivot shift test.”
Grade 3
50% of all ACL injuries are found to have associated meniscal injuries, what other structure joins these two to create the “unhappy triad”?
Medial Collateral Ligament
When is it likely that a bone contusion or microfracture has occurred alongside an ACL injury?
When there is a full rupture of the ACL as these are often traumatic and have “bruised the bone”.
How is an ACL injury diagnosed?
- Radiographs
- MRI
- Ultrasonography
- Instrumented Laxity Testing