Synovial joints are a type of joint with an articular capsule, consisting of an outer fibrous layer and an inner synovial membrane, which surrounds a fluid-filled synovial cavity. The articulating surfaces are covered by hyaline cartilage, designed to slide with little friction and to absorb compressive forces.
These joints are termed diarthroses, meaning they are freely mobile. They are more mobile than cartilaginous joints and fibrous joints.
Features of all synovial joints
articular capsule with synovial membrane
synovial cavity containing synovial fluid
Additional features within some synovial joints
fibrocartilaginous discs e.g. menisci within the knee joint
intracapsular ligaments e.g. cruciate ligaments within the knee joint
intracapsular tendons e.g. popliteus tendon within the knee joint
intra-articular tendons e.g. long head of biceps tendon within the shoulder joint
Additional features surrounding some synovial joints
fat pads e.g. infrapatellar fat pad
extracapsular ligaments
Types of synovial joints
ball-and-socket joint e.g. hip joint
hinge joint e.g. elbow joint
condyloid joint e.g. radiocarpal joint
saddle joint e.g. first carpometocarpal joint
pivot joint e.g. medial atlantoaxial joint
plane joint e.g. intercarpal joint