Ligament Injuries Flashcards
This ligament prevents anterior translation of the tibia
ACL
This ligament is typically injured during acceleration or deceleration with an uncontrolled Valgus moment at the knee with slight flexion with tibial IR or ER
ACL
This bundle of the ACL is most taught in flexion and is tested with the anterior drawer test
Anterior medial bundle
This bundle of the ACL is most taught near extension and is tested with the Lachman’s test. This is the biggest part of the ACL
Posterior lateral bundle
What two tests should be used to test the ACL?
Lachmans (sen: 85% and specificity: 94%) and pivot shift (sen: 24%, specificity 95% which increases to very high sen and sp if the patient is under anesthesia)
Risk factors for this ligament include: dry weather conditions, artificial turf, female sex, narrow intercondylar femoral notch size, lesser contacts depth of the medial tibial plateau, greater ant/post joint laxity
ACL
To signify an ACL injury when would you expect hemarthrosis?
0-12 hours
This ligament is the primary restraint to tibial posterior translation between 30-90* of flexion
PCL
This ligament is torn with a hyperflexion injury, hyperextension injury, or an external posterior directed force
PCL
What are the three PCL tests and what is the best?
Posterior drawer sn 90, sp 99
Posterior sag sign
Quad activation test
This is comprised of the lateral head of the gastroc, arcuate ligament, popliteus tendon, LCL, biceps tendon
Posterior lateral corner
Is often injured along with the PCL but can be injured in isolation with a direct blow to the proximal tibia or hyperextension injury
Posterior lateral corner
What are the two tests for posterior lateral corner?
Posterior drawer test: if positive at 30*
Dial test: pt in prone with knee bent to 30, tibia is taken to full ER and compared to other side. Looking for 10 difference
What does the MCL deep fibers attach to? What do the superficial fibers do?
Deep fibers attach to the medial meniscus superficial fibers restrict Valgus forces at the knee
This ligament has excellent blood supply and does not require surgery
MCL
Valgus stress test at 0* tests what? Valgus stress test at 30* tests what?
0* tests ACL and PCL
30* isolates MCL (pain or 5* of laxity is positive) pain: sn is 78% sp: 67%, laxity: sn 91%, sp 49%
This ligament is a cordlike structure the starts at the lateral epicondyle of the femur and attaches with the biceps femoris tendon at the fibular head
LCL
This ligament is the primary restraint to varus forces and secondary restraint to ER of the tibia
LCL
Varus stress test in full extension tests what? In 30* of flexion tests?
Full extension: ACL, PCL, LCL
30* tests LCL specifically
What other two ligaments reinforce the posterior medial joint capsule?
Oblique popliteal ligament and posterior oblique ligament
What does the medial arcuate ligament attach to?
Oblique popliteal ligament
What does the lateral branch of the arcuate ligament attach to?
Posterior aspect of the fibular head giving support to the posterior lateral knee joint capsule.
What are the Ottawa knee rules?
- Age >55
- Isolated tenderness of the patella with no other bony tenderness
- Tenderness to fibular head
- Unable to flex the knee to 90*
- Inability to bear weight immediately or in the ER
IKDC (international knee documentation committee) 2000 scale measures what?
Measures function, higher score means better function
KOOS (knee injury osteoarthritis outcome score) measures what?
0-100 and measures function, higher score the better function
Tegner scale is measured how?
0-10 point with higher number means better function
Marks scale is scored to what? Measures?
Scored 0-16 with higher score meaning higher function
What percent of the bad leg to good leg for quad strength, hop testing, and outcome measures mean return to sport?
90% of uninvolved leg
What is the tx following ACL reconstruction?
WB and NWB exercises within 4-6 weeks, 2-3 x per week, NMES for 6-8 weeks, post op brace, immediate mobilization and ice
Knee sprain tx
Supervised exercise that includes WB and NWB and use of NMR training
How do non contact ACL injuries occur?
Usually in acceleration or deceleration, at or near full extension. Quad contraction with reduced hamstring contraction.
ACLs fail at a rate of ___% and athletes that return to sport fail at a rate of __%.
15% and 23%
Of the 23% half are the other side
What is the one factor that predicts a second injury risk?
Time : return to sport in <9 mo increase injury 7x
What components are necessary for ACL prevention?
More than one exercise, need to include proximal exercises (core and trunk exercises), both plyo and strength components
What component is not necessary for ACL prevention?
Balance exercises
When should ACL prevention exercises be done?
Always throughout season, preseason can be used in addition, but just preseason was not enough
To screen for ACL copers these things have to be present:
Injury isolated to ACL
Knee has to have full pain-free ROM
No joint effusion
MVIC of quads is 70% of uninvolved side
After pre screening for copers is met then what are the criteria?
- Have to report no more than one instance of giving way
- Have to have 80% symmetry on 6 m hop test
- Score at least 80% on KOS ADL
- Score at least 60% for global rating of knee function
What is a cyclops lesion and what are signs?
It is a hypertrophied graft tissue at tibia or at the root of the torn ACL of highly vascularized tissue following ACL repair. It’s why extension is so important at first. Lacks terminal knee extension with gait, passive extension is limited with sharp anterior knee pain without changes in ROM
