True about synovial membrane of the knee joint is -

Ans. is 'a' i.e Invaginated posteriorly by cruciate ligament The knee is the largest and most complex joint of the body.The complexity is the result of the fusion of three joints in one.These 3 joints are:Lateral femorotibialMedial femorotibialFemoropatellar jointThe knee joint is supported by a no. of ligaments & cartilagesfibrous capsuleligamentum patella c) tibial collateral ligament d) fibular collateral ligamentumOblique popliteal ligamentArcuate popliteal ligamentCruciate ligamentsSemilunar cartilage ( Menisci)Transverse ligamentsCruciate ligamentThere are two cruciate ligaments Anterior and posterior.They are termed cruciate because they cross anterior and posterior from their tibial attachments.The anterior cruciate ligament is attached to the anterior intercondylar area of the tibia and passes upwards, backward and laterally to be attached to the posterior part of the medial surface of the lateral femoral condyle.The posterior cruciate ligament is attached to the posterior intercondylar area of the tibia and passes upwards forward and medially to be attached to the anterior part of the lateral surface of the medial femoral condyle.Synovial membrane: lines the capsule of the knee joint and is attached to the margins of the articular surfaces and to the peripheral edges of the menisci The synovial membrane, on the front of the joint forms a pouch which extends beneath the quadriceps femoris muscle forming the suprapatellar bursa.It also forms the following bursaePopliteal bursa*Semimembranous bursa*The cruciate ligaments have a complex relationship with the synovial membrane;From the posterior part of the fibrous capsule, the synovial membrane projects forwards in the intercondylar regions as a cul-de-sac to envelop the sides of both cruciate ligaments and to the front of the anterior cruciate ligament. Thus even though the cruciate ligaments are intracapsular, are extra-synovial structures.Well, I think that this explanation is somewhat confusing; that's because of the lack of a 3-dimensional figure. So just turn over the pages of your Anatomy book along with Grant's Atlas. If you don't have time to do so just learn these 3 points:The knee joint communicates with the following bursae:Suprapatellar bursaPopliteal bursaSemimembranous bursathe surface of the menisci have no synovial covering synovial membrane is invaginated posteriorly by the cruciate ligament