KNEE JOINT
•One of the largest and complex joint.
•Formed by lateral femorotibial, medial femorotibial and femoropatellar articulations.
•Articular surfaces:
•Condyles of femur
•Condyles of tibia
•Patella
•LIGAMENTS:
•Fibrous capsule:
•It is thin and absent anteriorly where it is replaced by the tendon of quadriceps, patella
and ligament patellae.
•Fibrous capsule (external fibrous layer) Synovial membrane (Internal layer)
•Fibrous layer →Make the intrinsic ligaments.
•Attached → superior on femur (Proximal to articular area).
•Posterior → Covers condyles + intercondylar fossa.
•Inferior → margins of tibial plateau.
•Coronary ligament and short lateral ligament are the parts of the fibrous capsule:
•Fibrous capsule is being strengthened by
–Medial and lateral patellar reticula (Anterior)
–Iliotibial tract (Lateral)
–Sartorius and semimembranous (Medial)
–Oblique popliteal ligament (Posterior)
•Opening → Leads to supra patellar bursa
–Exit for popliteus tendon.
•Synovial membrane → All the surface bounding the articular cavity (Joint cavity)
Patella and menisci are covered.
•Patellar ligament → (anterior ligament of knee joint). Also receives aponeurotic
expansions of vastus medialis, vastus lateralis and deep fascia (Medial and lateral pattelar
retinacula).
•Medial collateral (Tibial collateral ligament → Medial epicondyle of femur to
condyle of femur → superior part of medial surface of tibia.
•Lateral collateral (Fibular collateral ligament
of head of fibula.
Lateral epicondyle → lateral surface
•Oblique popliteal ligament → Expansion of semimembranosus from medial tibial
condyle to lateral femoral condyle.
•Arcuate popliteal ligament → Posterior aspect of fibula → spreads to knee joint.
•Intra capsular ligament:
•Cruciate → Crossing each other
•Out side the synovial cavity
•Below the capsule
•Anterior cruciate ligament:
•Anterior intercondylar area of tibia
•To posterior surface of medial side of lateral condyle and tibia. Prevents → Posterior
displacement of femur.
•Posterior cruciate ligament:
•Posterior intercondylar area prevents → anterior displacement of femur attached on
anterior part of lateral surface of medial condyle
•Menisci → Fibro cartilaginous plates deepens the articular surface and play a role in
shock absorption.
•Coronary ligament portions of joint capsule between the meniscal margins and tibial
condyles.
•Transverse Ligament → Between the anterior edges of menisci
•Anastomosis around knee joint:
•Femoral / Sciatic / obturator nerve
•Locking and unlocking of knee joint
•Flexion → Biceps, Semimembranosus, Semitendinosus, Gracilis, Sartorius, Popliteaus,
Gastrocnemius
•Extension → Quadriceps femoris, tensor fascia lata.
•Medial rotation → Popliteus, semis (Membranosus and tendosus) sartorius gracillis.
•Lateral rotation → Biceps femoris
•Articular surfaces are not congruent (Tibial condyles are small)
•Leg may be abnormally abducted and adducted (Rickets etc).
•Osteoarthritis, aspiration of fluid.
•Arthroscopy
•Injury to mensci, ligaments etc.