Ginglymus and condyloid - the condyles of the occiput rest on the superior articular facets of the atlas (condyloid portion); the condyles converge anteriorally and allow motion in only one plane (flexion and extension - hinge portion)
Anterior atlanto-occipital membrane - anterior arch of atlas to anterior margin of foramen magnum, direct continuation of the anterior longitudinal ligament
Atlanto-occipital Joint
Posterior atlanto-occipital membrane - posterior arch of atlas to posterior margin of foramen magnum
Lateral Atlanto-occipital membrane - (Anterior Oblique Ligament), these two ligaments connect TP of atlas to jugular process of occiput
Articular Capsule (capsular ligament) - these ligaments enclose the articular surfaces and are lined with a synovial membrane
Occipito-Axial Complex
the axis is NOT in direct articulation with the occiput so it is called a complex NOT a joint
Ligaments attach the axis to the occiput
Membrana-tectoria - occipito-axial ligament, tectorial membrane - continuation of the posterior longitudinal ligament; attaches on the occipital bone medial to the hypoglossal canal; closely adherent to the cranial dura once inside the cranial vault
Alar Ligament - check ligament, odontoid ligament; one on each side, apex of dens to medial surface of occipital condyles, serve to limit or check the degree of rotation of the axis
Occipito-Axial Complex
Apical ligament (suspensory ligament) - single ligament, tip of dens to anterior margin of foramen magnum; may be remains of embryonic notochord as there is no disc here
Cruciate ligament - 3 components
transverse ligament of the atlas - lateral mass over posterior aspect of dens to lateral mass
cranial crus - attaches central portion of the transverse ligament to ant. margin of FM
caudal crus - attaches central portion of the transverse ligament to posterior body of axis
Atlantoaxial Joints
2 joints here: both are Synovial, diarthrodial
1) bilateral joints between the inferior articular facets of the atlas and the superior articular facets of the axis; these zygapophyseal joints are plane, gliding joints
2) articulation between dens and anterior arch of the atlas and the dens and the transverse ligament of the atlas - trochoid, pivot joint
Atlantoaxial Joints
Ligaments associated with the Atlanto-axial joint
Anterior atlanto-axial ligament - anterior surface of body of axis to anterior arch of atlas
Posterior atlanto-axial ligament - from the laminae of the axis to the posterior arch of the atlas
Accessory Ligaments - runs from the medial surface of the lateral masses of atlas down to the posterior surface of the body at the base of dens
Transverse Ligament of the Atlas - runs from lateral mass across the neural ring over the posterior aspect of the dens to hold the dens firmly against the fovea dentalis of the atlas, does not attach to the dens, small synovial pocket between the two
Joint of Luschka
Uncovertebral joint
Diarthrosis, synovial
Between the uncinate processes and a small indentation found on the inferior surface of the vertebra it articulates with
typically undergo degeneration with resulting bony outgrowth which may encroach on neighboring structures such as the vertebral artery and the exciting spinal nerves
Transverse acetabular ligament - crosses the acetabular notch, connects joint capsule to ligamentum capitis femoris
Tibiofemoral - Stifle Joint
Largest and most complex joint of body,
Synovial, diarthrodial, “modified hinge”, biaxial
Classified as a double condyloid joint, capable of flexion, extension and medial and lateral rotation
Hyperextension of knee - foot on ground, medial rotation of femur
Ligaments
Function
control excessive knee extension
control abduction and adduction stresses
control anterior and posterior displacement of tibia on femur
control medial and lateral rotation of tibia beneath femur
give rotatory stabilization
Ligaments of the knee, cont.
Lateral and medial patellar retinacula - tendinous insertion of quadriceps femoris m. Gives anterior stability. Attaches to patella and tibial tuberosity
Oblique popliteal ligament - posterior aspect of joint capsule, provides posterior stability and limits hyperextension.
Arcuate popliteal ligament - Head of fibula over tendon of popliteus m. to intercondylar area of tibia and lateral epicondyle of femur. Limits hyperextension of knee.
Collateral Ligaments - provide medial and lateral stability
Medial (tibial) collateral ligament
Lateral (fibular) collateral ligament
Cruciate ligaments
Anterior cruciate ligament
Anterior tibia to posterior medial aspect of the lateral condyle of the femur
Prevents anterior displacement of the tibia on the femur
During extension of the knee the ACL is pulled taut
Torn ACL = Anterior drawer sign
Posterior cruciate ligament
Posterior tibia to lateral aspect of medial condyle of femur, prevents posterior displacement of the tibia.
Shorter and less oblique than ACL
During flexion of the knee the PCL is pulled taut
Torn PCL = Posterior drawer sign
Bursa
Popliteal bursa - between tendon of popliteus m. and lateral condyle of femur
Prepatellar bursa - between patella and skin
Suprapatellar bursa - between quadriceps tendon and anterior femur
Menisci
Medial meniscus - semicircular, attached to medial collateral lig. And to semimembranosus m.
Lateral meniscus - 4/5’s of a circle, attached to posterior cruciate lig. And popliteus muscle via coronary lig. And posterior joint capsule.
