knee Flashcards
what does the knee link?
- two longest bones together
what are the roles of the knee?
- holds bodyweight
- actions e.g., running ^ pressure on knee
what joint type is the knee? what does it do?
- synovial joint
- connects multiple bones and allows high range of motion
what does the joint contain?
- contains synovial fluid
- acts as a lubricant inside the joint
what does articular cartilage do?
- reduces the friction of the bones
- no wear and tear
- covers the bone ends
what surrounds the joint and why?
- joint capsule
- provides support and stability
is the knee joint complete?
- no, it is incomplete due to hole at the front
- plugged by patella tendon
what are the two main joints of the knee?
- tibiofemoral
- patellofemoral
what is the tibiofemoral joint?
- joint between the femur and tibia
how many axis can you perform movement in the tibiofemoral joint?
- 2 axis as it is bi-axial
- flexion/ extension
- abduction/ adduction
what is the patellofemoral joint?
- joint between the patella and femur
what kind of joint is the patellofemoral joint?
- saddle joint
what are the 4 bones of the knee joint?
- femur
- patella
- fibula
- tibia
what is the patella?
- largest sesamoid bone
- embedded in quadriceps tendon
what are the roles of the patella?
- anatomic pulley
- reduces friction as covered in cartilage
where does the patella sit? what does it do?
- anterior to femur
- kneecap slides along the femur as the knee bends
what connects the patella to the tibia?
- connective tissue
what are the bony ends called? where do they sit?
- condyles
- stick down out of the femur
- sit into grooves on tibial plateau
what are menisci?
- C shaped concave surface
- provides side to side stability as it wraps around the condyles
what are the two types of menisci?
- lateral
- medial
what does the menisci act as?
- cushion for the femur
- creates greater SA
what are the other roles of the menisci?
- increase congruency
- assist weightbearing
- absorbs shock
what do ligaments of the knee connect and provide?
- connects femur and tibia
- provides stability
what are the 4 ligaments?
- anterior cruciate ligament
- posterior cruciate ligament
- medial collateral ligament
- lateral collateral ligament
where does the anterior cruciate ligament originate and insert?
- originates at posteromedial surface of lateral femoral condyle
- inserts into anterolateral tibial spine
what does the anterior cruciate ligament split into? what does it do?
- splits into two bundles
- prevents anterior tibial displacement
where does posterior cruciate ligament originate and insert?
- originates at the anterolateral surface of the medial femoral condyle
- inserts to posterior intercondylar area
what does the posterior cruciate ligament split into? what does it do?
- splits into two bundles
- prevents posterior tibial displacement
what is the medial collateral ligament ? where does it originate and insert ?
- broad flat band
- originates at medial epicondyle of femur
- inserts into tibia condyle
what is the role of the medial collateral ligament?
- prevents tibia moving medially/ valgus displacement
what is the lateral collateral ligament ? where does it originate and insert?
- thin and shorter strong cord
- originates from lateral epicondyle
- inserts into fibula head
what does the lateral collateral ligament do?
- prevents the tibia moving laterally
- varus displacement
what is the difference between cruciate ligaments and collateral ligaments?
- cruciate are intracapsular and prevent movement forwards/ backwards
- collateral are extracapsular and provide rotational stability
where are knee flexors located?
- posteriorly
what are the six knee flexors?
- gastrocnemius
- biceps femoris
- semitendinosus
- semimembranosus
- gracilise
- sartorius
where does the gastrocnemius originate and insert ?
- originates at medial condyle (medial head) and lateral condyle (lateral head)
- inserts into posterior aspect of calcaneus
where does the biceps femoris originate and insert?
- originates on lower medial ischial tuberosity (long head) and linea aspera (short head)
- inserts into fibula head
where does the semitendinosus originate and insert?
- originates on lower medial ischial tuberosity
- inserts into pes anserinus
where does the semimembranosus originate and insert?
- originates at upper lateral ischial tuberosity
- inserts into posteromedial surface of medial tibial condyle
where does the gracilis originate and insert?
- originates at inferior pubic ramus
- inserts into pes anserinus
where does the sartorius originate and insert?
- originates on ASIS
- inserts into pes anserinus
where are the knee extensors located?
- anteriorly
- above thigh
what are the five knee extensors?
- rectus femoris
- vastus lateralis
- vastus medialis
- vastus intermedius
- tensor fascia latae
where does the rectus femoris originate and insert?
- originates at ASIS (long head) and groove above acetabulum (short head)
- inserts into base/ upper border of patella and tibial tuberosity
where does vastus lateralis originate and insert?
- originates on intertrochanteric line, greater trochanter and lateral lip of linea aspera
- inserts into tendon of rectus femoris/ lateral border of patella
where does the vastus medialis originate and insert?
- originates at intertrochanteric line, medial lip of linea aspera and medial supracondylar line
- inserts into tendon of RF, medial patella and tibial condyle
where does the vastus intermedius originate and insert?
- originates at upper anterior and lateral surface of femur
- inserts into deep surface of rectus femoris / base of patella
where does the tensor fascia latae originate and insert?
- originates on anterior iliac crest
- inserts into iliotibial band
what are the five medial rotators of the knee?
- semitendinosus
- semimembranosus
- gracilis
- sartorius
- popliteus
where does popliteus originate and insert?
- originates at lateral femoral condyle
- inserts into posterior surface of tibia
what is the lateral rotator of the knee?
- biceps femoris
