A shorter patellar tendon = baja while a longer one = alta The patella encounters the condyles at 15-20˚ of flexion Medial femoral condyle is more curved & medial tibial condyle is more concave front to back In weight bearing (WB), femur rotates on tibia whereas in non- WB (NWB) tibia rotates on femur Hamstrings are mostly strap/fusiform design, better for ROM & creates most force eccentrically (esp near end ROM) The articular cavity does not include the cruciate ligaments as the capsule folds around the intercondylar area Compressive forces behind the patella increase by a factor of 0.5x body weight, 3.3x with stairs, & 7.6x with squats Medial femoral condyle twists inward toward lateral condyle in sagittal plane; both wider most distally Intercondylar eminence separates medial & lateral tibial plateau; gives rise to ACL & PCLs Average Q-angle is ~15˚; beyond 20˚ is knock-kneed or genu valgus whereas less than 10˚is bow-legged or genu varum The knee’s synovial membrane is the most extensive in the body with lots of bursae due to overlapping strap- like muscles With slack ligaments, we have ~40˚ of rotation at 90˚ of knee flexion Menisci (shallow bowls of fibrocartilage) deepens tibial plateau with medial larger & oval shaped, while lateral smaller & rounder Quads are multipennate design, better for power, with the patella increasing peak torque @ ~60˚flexion The patella, a sesamoid bone, slides against smooth space between condyles & provides an increased moment arm for the quads during knee extension The ACL resists anterior tibial glide while the PCL resists posterior tibial glide The MCL resists valgus force while the LCL resists varus force Knee rotation due to joint structure (vs. muscle function) aka screw home mechanism for stability in extension More flexion leads to more patella compression where the cartilage is the thickest All knee ligaments are tightest in extension Menisci are thinnest @ middle of joint and widest at outermost part In addition to quads & hamstrings, other knee muscles include sartorius, popliteus, gastrocs, and plantaris The knee is actually a double hinge with different shapes of fused lateral and medial condyles; this allows some rotation Wedge-shaped menisci provide increased surface area and stability for the knee joint A shorter patellar tendon = baja while a longer one = alta The patella encounters the condyles at 15-20˚ of flexion Medial femoral condyle is more curved & medial tibial condyle is more concave front to back In weight bearing (WB), femur rotates on tibia whereas in non- WB (NWB) tibia rotates on femur Hamstrings are mostly strap/fusiform design, better for ROM & creates most force eccentrically (esp near end ROM) The articular cavity does not include the cruciate ligaments as the capsule folds around the intercondylar area Compressive forces behind the patella increase by a factor of 0.5x body weight, 3.3x with stairs, & 7.6x with squats Medial femoral condyle twists inward toward lateral condyle in sagittal plane; both wider most distally Intercondylar eminence separates medial & lateral tibial plateau; gives rise to ACL & PCLs Average Q-angle is ~15˚; beyond 20˚ is knock-kneed or genu valgus whereas less than 10˚is bow-legged or genu varum The knee’s synovial membrane is the most extensive in the body with lots of bursae due to overlapping strap- like muscles With slack ligaments, we have ~40˚ of rotation at 90˚ of knee flexion Menisci (shallow bowls of fibrocartilage) deepens tibial plateau with medial larger & oval shaped, while lateral smaller & rounder Quads are multipennate design, better for power, with the patella increasing peak torque @ ~60˚flexion The patella, a sesamoid bone, slides against smooth space between condyles & provides an increased moment arm for the quads during knee extension The ACL resists anterior tibial glide while the PCL resists posterior tibial glide The MCL resists valgus force while the LCL resists varus force Knee rotation due to joint structure (vs. muscle function) aka screw home mechanism for stability in extension More flexion leads to more patella compression where the cartilage is the thickest All knee ligaments are tightest in extension Menisci are thinnest @ middle of joint and widest at outermost part In addition to quads & hamstrings, other knee muscles include sartorius, popliteus, gastrocs, and plantaris The knee is actually a double hinge with different shapes of fused lateral and medial condyles; this allows some rotation Wedge-shaped menisci provide increased surface area and stability for the knee joint
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A shorter patellar tendon = baja while a longer one = alta
The patella encounters the condyles at 15-20˚ of flexion
Medial femoral condyle is more curved & medial tibial condyle is more concave front to back
In weight bearing (WB), femur rotates on tibia whereas in non-WB (NWB) tibia rotates on femur
Hamstrings are mostly strap/fusiform design, better for ROM & creates most force eccentrically (esp near end ROM)
The articular cavity does not include the cruciate ligaments as the capsule folds around the intercondylar area
Compressive forces behind the patella increase by a factor of 0.5x body weight, 3.3x with stairs, & 7.6x with squats
Medial femoral condyle twists inward toward lateral condyle in sagittal plane; both wider most distally
Intercondylar eminence separates medial & lateral tibial plateau; gives rise to ACL & PCLs
Average Q-angle is ~15˚; beyond 20˚ is knock-kneed or genu valgus whereas less than 10˚is bow-legged or genu varum
The knee’s synovial membrane is the most extensive in the body with lots of bursae due to overlapping strap-like muscles
With slack ligaments, we have ~40˚ of rotation at 90˚ of knee flexion
Menisci (shallow bowls of fibrocartilage) deepens tibial plateau with medial larger & oval shaped, while lateral smaller & rounder
Quads are multipennate design, better for power, with the patella increasing peak torque @ ~60˚flexion
The patella, a sesamoid bone, slides against smooth space between condyles & provides an increased moment arm for the quads during knee extension
The ACL resists anterior tibial glide while the PCL resists posterior tibial glide
The MCL resists valgus force while the LCL resists varus force
Knee rotation due to joint structure (vs. muscle function) aka screw home mechanism for stability in extension
More flexion leads to more patella compression where the cartilage is the thickest
All knee ligaments are tightest in extension
Menisci are thinnest @ middle of joint and widest at outermost part
In addition to quads & hamstrings, other knee muscles include sartorius, popliteus, gastrocs, and plantaris
The knee is actually a double hinge with different shapes of fused lateral and medial condyles; this allows some rotation
Wedge-shaped menisci provide increased surface area and stability for the knee joint
