Knee ligament CPG Flashcards
- The incidence of ligamentous injury from greatest to least is:
ACL, PCL, MCL, LCL
- The most common multiligamentous injuries include:
o ACL and MCL
o Posterolateral corner (PLC) and either the ACL or PCL
What demographics have the highest incidence of ligamentous injury?
- Ligamentous knee injury is substantially higher for people in the military and professional athletes; moderately higher for amateur athletes
What are the stats for second ACL injury following ACL reconstruction?
o patients under the age of 25 have a second ACL injury rate of 21%
o athletes under the age of 25 who return to sport have a second ACL injury rate of 23%
o Female athletes returning to sport are 4.5x more likely to have a second ACL injury within 24 months than female controls
What sports are arguably the most dangerous for ACL injury?
- soccer accounts for a third of all ACL reconstructions, however football is more dangerous for males.
- skiing carries a higher risk of injury in general, but lower volume of injury
What is the standard mechanism of ACL injury?
o Non-contact
o Acceleration or deceleration with excessive quad contraction and reduced hamstring co-contraction at or near full extension.
o Loading is higher with quadriceps force combined with knee internal rotation, a valgus load combined with knee internal rotation, or excessive valgus loads applied during weight bearing deceleration activities
What is/are the standard mechnism(s) for PCL injury?
o “dashboard/anterior tibial blow injury” (38.5%),
o fall on the flexed knee with the foot in plantar flexion (24.6%)
o a sudden violent hyperextension of the knee joint (11.9%)
What is the standard mechanism for PLC injury? (isolated)
Isolated injury to the PLC can occur from a posterolateral directed force to the proximal medial tibia with the knee at or near full extension, forcing the knee into hyperextension and varus.
What is the standard mechanism for PLC injury? (combined)
Combined PLC injuries can result from knee hyperextension, external rotation, and varus rotation; complete knee dislocation; or a flexed and externally rotated knee that receives a posteriorly directed force to the tibia
What does the evidence say about early vs delayed ACL reconstruction?
- There is high quality evidence that shows:
o No difference between early and delayed ACL reconstruction for multiple outcomes including knee laxity/instability and return to sport levels
o No difference between early ACL reconstruction with structured rehabilitation and structured rehabilitation with the option for delayed ACL reconstruction at 5 year follow up with multiple outcome measures
Are there differences between quad tendon, hamstring tendon, or patellar tendon grafts for ligamentous stability and patient reported outcomes?
- Level II evidence shows that outcomes are generally similar between graft types
What are the expectations following ligament injury and surgical management with regards to graft type and timing of surgery?
The clinical course for most patients after ligament injury and surgery is satisfactory, with no differences between graft type or timing of surgery.
Can people expect to return to sport following ligamentous injury and surgical management?
Rates of return to any sport are good, but there are substantially lower rates for return to preinjury levels or competitive sports. Physical impairments, performance-based tests, PROs, and psychological responses may influence return-to-sport rates.
Is there an effect of psychological factors on return to sport following ACL reconstruction?
yes
Other important factors include psychological responses, including fear of movement/reinjury, athletic confidence, self-efficacy, and emotions, after ACL reconstruction.
What two environmental (literally) conditions are associated with risk of ACL injury?
- Dry weather conditions and artificial turf surface
What are other risk factors associated with the risk of ACL injury? (6)
- Female sex
- narrow intercondylar femoral notch size
- lesser concavity depth of the medial tibial plateau
- greater anterior/poste¬rior tibiofemoral joint laxity
- prior ACL reconstruction
- familial predisposition
Is the magnitude of the posterior slope of the tibia a risk factor for ACL injury?
- conflicting evidence
Are there biomechanical or neuromuscular risk factors associated with non-contact ACL injury?
- no evidence to support their existence at this time
What are the CPG diagnostic criteria for ACL sprain diagnosis? (6)
o Mechanism of injury consisting of deceleration and acceleration motions with noncontact valgus load at or near full knee extension
o Hearing or feeling a “pop” at time of injury
o Hemarthrosis within 0 to 12 hours following injury
o History of giving way
o Positive Lachman test with “soft” end feel or increased anterior tibial translation (sensitivity, 85%; 95% CI: 83%, 87% and specificity, 94%; 95% CI: 92%, 95%)
o Positive pivot shift test (sensitivity, 24%; 95% CI: 21%, 27% and specificity, 98%; 95% CI: 96%, 99%)
What are expected movement coordination impairment measures following ACL sprain that can assist diagnosis? (3)
- 6-meter single-limb timed hop test result that is less than 80% of the uninvolved limb
• Maximum voluntary isometric quadriceps strength index that is less than 80% using the burst superimposition technique
• Reported history of giving-way episodes with 2 or more activities of daily living (ADLs)
What are the CPG diagnostic criteria for PCL sprain diagnosis? (4)
o Posterior-directed force on the proximal tibia (dashboard/ anterior tibial blow injury), a fall on the flexed knee, or a sudden violent hyperextension of the knee joint
o Localized posterior knee pain with kneeling or decelerating
o Positive posterior drawer test at 90° with a nondiscrete end feel or an increased posterior tibial translation (sensitivity, 90%; 95% CI not available and specificity, 99%; 95% CI not available)
o Posterior sag (subluxation) of the proximal tibia posteriorly relative to the anterior aspect of the femoral condyles (sen¬sitivity, 79%; 95% CI: 57%, 91% and specificity, 100%; 95% CI: 85%, 100%)
What are the CPG diagnostic criteria for MCL sprain diagnosis? (5)
o Trauma by a force applied to the lateral aspect of the lower extremity
o Rotational trauma
o Medial knee pain with valgus stress test performed at 30° of knee flexion (sensitivity, 78%; 95% CI: 64%, 92% and specificity, 67%; 95% CI: 57%, 76%)
o Increased separation between the femur and tibia (laxity) with a valgus stress test performed at 30° of knee flexion (sensitivity, 91%; 95% CI: 81%, 100% and specificity, 49%; 95% CI: 39%, 59%)
o Tenderness over the MCL and its attachments reproduces familiar pain
What are the CPG diagnostic criteria for LCL sprain diagnosis? (5)
o Varus trauma
o Localized swelling over the LCL
o Tenderness over the LCL and its attachments reproduces familiar pain
o Lateral knee pain with varus stress test performed at 0° and 30° of knee flexion
o Increased separation between the femur and tibia (laxity) with varus stress test applied at 0° and 30° of knee flexion
What are the key clinical findings indicative of knee instability as a clinical diagnosis? (11)
o Symptom onset linked to precipitating trauma
o Deceleration, cutting, or valgus motion associated with injury
o “Pop” heard or felt at time of injury
o Hemarthrosis within 0 to 12 hours following injury
o Knee effusion present
o Sense of knee instability reported
o Excessive tibiofemoral laxity with (cruciate/collateral) ligament integrity tests
o Pain/symptoms with (cruciate/collateral) ligament integrity tests
o Lower-limb strength and coordination deficits
o Impaired single-leg proprioception/balance
o Abnormal compensatory strategies observed during deceleration or cutting movements
