L21-knee joint

Question 1

what type of joint is the knee joint?

Answer 1

it is a synovial modified hinge joint

Question 2

what are the articular surfaces of the knee joint?

Answer 2

lower ned of the femur upper end of the tibia and posterior surface of the patella

Question 3

name the 4 extra-capsular ligaments of the knee joint

Answer 3

1) the ligamentum patellae
2) the lateral collateral ligament
3) the medial collateral ligament
4) the oblique popliteal ligament

Question 4

what are the attachment of the ligamentum patellae?

Answer 4

it is attached over the lower boarder of the patellae and above the tuberosity of the tibia. it is a continuation of the central part of the common tendon of the quadriceps femoris muscle

Question 5

what are the attachments of the lateral collateral ligaments?

Answer 5

it is attached above the lateral epicondyle of the femur and below the head of fibula. the tendon of the popliteus muscle intervenes between the ligament and the lateral meniscus

Question 6

what are the attachments of the medial collateral ligament?

Answer 6

it is attached above the the medial epicondyle of the femur and below the medial surface of the shaft of the tibia. it is firmly attached to the edge pf the medial meniscus

Question 7

what are the attachments of the oblique popliteus ligament?

Answer 7

it is a tendinous expansion of the semimebrinousus muscle. it strengthens the posterior aspect of the capsule

Question 8

what are the intra-capsular ligaments of the knee joint

Answer 8

anterior and posterior cruciate ligaments

Question 9

what are the attachments of the anterior cruciate ligament?

Answer 9

it is attached from the anterior interchondylar area of the tibia to the lateral femoral condyle. it prevents hyperextension and posterior displacement of the femur and tibia

Question 10

what are the attachments of the posterior cruciate ligament

Answer 10

it is attached from the posterior interchondylar area of the tibia to the medial femoral condyle. it prevents anterior displacement of the femur and the tibia

Question 11

what is the suprapatellar bursa?

Answer 11

it is an extension of the synovial membrane where it extends beneath the quadriceps muscle above the patella to form the suprapatellar bursa

Question 12

what is the infrapatellar bursa?

Answer 12

it is an extension of the synovial membrane where it is reflected backwards from the posterior aspect of the ligamentum patellae to form the infrapatellar fold

Question 13

what is the popliteal bursa?

Answer 13

at the back of the knee joint the synovial membrane extends downwards on the deep surface of the tendon of popliteus muscle forming the popliteal bursa

Question 14

what is the semimembranosus bursa?

Answer 14

it is an extension of the synovial membrane where it is interposed between the medial head of gastrocnemius and medial femoral condyle and the semimembranosus tendon

Question 15

what are the structures that can be found inside the knee?

Answer 15

medial meniscus
lateral meniscus
anterior cruciate ligament
posterior cruciate ligament
popliteus tendon

Question 16

what is the medial meniscus?

Answer 16

it is C-shaped fixed to the capsule of the knee joint and to the medial collateral ligament (liable to injury)

Question 17

what is the lateral meniscus?

Answer 17

it has a circular shape, separated from the capsule and the lateral collateral ligament by the tendon of the popliteus muscle (less liable to injury)

Question 18

what are the function of the menisci?

Answer 18

1) they increase the concavity of the tibial condyles for better adaptation with the femoral condyles
2)they maintain a potential joint space for flushing synovial fluid to provide nutrition tot the articular cartilage
3#)they act as shock absorbers

Question 19

what is the arterial supply of the knee joint?

Answer 19

from anastomoses around the knee joint

Question 20

what stabilizes the knee joint?

Answer 20

muscles: quadriceps femoris the inferior fibres of the vasti lateralis and medialis
ligaments: mainly the quadriceps ligaments
menisci

Question 21

what structures are involved in the TRIAD injury and what is it?

Answer 21

medial collateral ligament-medial meniscus and the anterior cruciate ligament. the joint becomes filled with blood hemartherosis

Question 22

outcome of inflammation of the bursa?

Answer 22

housemaid knee:subcutaneous pre-patellar bursa

Question 23

osteoarthritis of the knee?

Answer 23

total knee replacement or knee joint arthroplasty done in severe destructive arthritis of the knee joint