Wk 4: knee joint Flashcards
Knee Joint Complex
at least two synovial joints within one capsule
- Tibiofemoral: medial and lateral part
- Patellofemoral
Tibiofemoral joint classification
- Synovial
- Condyloid
- Biaxial
Tibiofemoral joint movements
- Flexion 140º
- Extension 0-5º
- Internal/medial rotation 10º-20º if flexed
- External/lateral rotation 30º-40º if flexed
Tibiofemoral joint number of axes
two
Tibiofemoral Articular Surfaces
- Femoral condyles: convex, medial & lateral
- Tibial condyles: flat and separated by intercondylar area
Patellofemoral articular surfaces
- Patella surface of femur
- Articular surface of patella (facets)
Patellofemoral classification
- Synovial
- Plane
Patellofemoral movements
- Gliding
Patella type of bone
- Sesamoid bone: base, apex, articular facets
Joint Capsule
- Attaches to articular margins (femoral condyles)
- Attaches to medial & lateral margins (tibial condyles)
- Incomplete and thin: anteriorly (quadriceps tendon & patellar ligament) and posteriorly (e.g. popliteus tendon)
Knee Retinacula
- Medial & lateral patellar retinaculum
- From vastus medialis & vastus lateralis
- Lateral retinaculum blends with iliotibial tract
- Medial retinaculum blends with periosteum of tibia
Patella function
- Mechanical advantage for knee extension
Patella location
- Centred in intercondylar groove of femur
Synovial Membrane location
Anteriorly attaches to patella
Posteriorly closes off intercondylar fossa
Synovial Membrane
- Lines the joint capsule
- Extensive and complex
- Does not enclose the cruciate ligaments
- Communicates with some bursa
Bursae includes
- Pes anserine (on medial tibia)
- Suprapatellar (extends 6cm superior to patella)
- Infrapatellar
- Prepatellar
Extracapsular ligaments
Fibular/Lateral collateral ligament
Popliteofibular ligament
Patella ligament
Tibial/Medial collateral ligament
Oblique Popliteal
Arcuate Popliteal
Anterolateral ligament
Intracapsular ligaments
Anterior Cruciate Ligament ACL
Posterior Cruciate Ligament PCL
Posterior meniscofemoral
Medial & Lateral Meniscus
Fibular collateral ligament attatches
Lateral femoral epicondyle
Fibular collateral ligament limits
extension
lateral rotation
Fibular collateral ligament prevents
adduction
Popliteofibular ligament attatches
popliteus tendon
- Apex of head of fibula
Popliteofibular ligament limits
lateral rotation of the tibia
Patella ligament attatches
- From patella to tibial tuberosity
- Continuation of quadriceps tendon
- Receives retinacula
Patella ligament function
mechanical advantage in knee extension
Tibial collateral ligament attatches
Medial femoral epicondyle
Medial tibial condyle & shaft
Medial meniscus
Tibial/Medial collateral ligament limits
extension
medial rotation
Tibial collateral ligament prevents
abduction
Oblique Popliteal function
Strengthens central posterior joint capsule
Oblique Popliteal location
- Expansion of semimembranosus
- Travels superolaterally to femur
Arcuate Popliteal function
Strengthens inferolateral posterior joint capsule
Arcuate Popliteal location
Is an expansion of the tendon of biceps femoris attachment
- Travels superomedially over popliteus
Anterolateral ligament attachment and location
Attaches: lateral femoral condyle
Location: midway between anterolateral tubercle & head of fibula
Anterior Cruciate Ligament attatches
Anterior intercondylar area of tibia
Posteromedial surface of lateral femoral condyle
Anterior Cruciate Ligament limits
anterior slide of tibia on femur
medial rotation
Anterior Cruciate Ligament type
Extra-synovial
Posterior Cruciate Ligament attatches
Posterior intercondylar area of tibia
Lateral medial femoral condyle
Posterior Cruciate Ligament limit
posterior slide of tibia on femur
medial rotation
Posterior Cruciate Ligament type
Extra-synovial
Posterior meniscofemoral attatches
Connects lateral meniscus to PCL
Posterior meniscofemoral purpose
Secondary restraint to support PCL
Medial & Lateral Meniscus purpose
Shock absorption
Increase congruence