hello all this is dr alsup and in this video we will be discussing the
six main types of synovial joints and during this discussion of the
types we will talk about what movements are possible at each joint and examples of each
so as i mentioned at the beginning there are going to be six main types of synovial joints
and these are typically divided into these types by the shape of their articulating bony surfaces
and that shape will really greatly affect what types of actions are possible at each
so let's start with the ball and socket joint because it's kind of my favorite so i like to
start with my favorites these joints consist of a ball like surface often called a head fitting
into a socket or a cup like surface and these types of joints this type of joint is capable
of all the movements we describe as possible at a synovial joint so this includes flexion
and extension abduction and adduction which means it can also circumduct if it can do those four
and as well as medial and lateral rotation so the most freely movable of the synovial joints the two
main ball and socket joints are the glenohumeral or the shoulder joint as well as the hip joint
all right let's continue clockwise on this image with our next stop being at the chondrulloid
sometimes referred to as ellipsoid or ellipsoidal joints
now in condyloid joints you have two relatively oval shaped projections and depressions fitting
together and these joints are capable of movements in two planes so often referred to as biaxial
these joints are capable of flexion and extension as well as abduction and adduction and when this
and with this complex of movements that also can lead to circumduction you can find an example of
a condyloid joint at the radiocarpal joint which sometimes is referred to as the wrist joint this
will be between the radius and the proximal row of the carpal bones so this one right here
would be the radiocarpal joint and that is a conjuloid joint
um i lied and i and i'm actually not going to go exactly clockwise because i want to skip
to the saddle joint uh that because it's actually pretty similar to the conjuloid joint in terms
of the type of movements allowed but the saddle joint will have a bit a greater range of motion
one of the articular surfaces in the saddle joint will be as its name suggests saddle shaped and the
other bone will fit into that saddle shaped bone and the first um the first carpometacarpal joint
is going to be an example and it's hard to see that here but this is going to be an example
of a saddle joint in fact it's one of the only examples of a saddle joint all right circling back
to the plane joint the articulating surfaces of the plane joint are pretty flat maybe a little bit
of concavity or convexity but for the most part think flat and these bones will mainly
or these surfaces will mainly just glide over one another kind of side to side or back and forth
but and bones may rotate against one another there are actually quite a few plane joints
throughout the body and while they often don't produce big movements they can help
facilitate bigger movements at other joints so the joints between many of the tarsal bones are going
to be plain joints uh as well as between many of the wrist joint or the carpal bones so the the
joints between each one of those individual carpal bones the acromioclavicular joint or your ac
joint is another example of a plane joint and that particular plane joint and those small movements
that occur there can really help better facilitate the movements at the ball and socket joint to have
those more those bigger more almost more explosive movements that can occur at this pretty uh
this pretty freely movable ball and socket shoulder joint
okay hinge joints are some of the more intuitive joints and are relatively
simple in terms of actions allowed this will allow flexion and extension all right so it could either
be kind of that way or that way in terms of the movements it's really only occurring in one plane
so these can be called uni axial the elbow joint is a great example of a hinge joint the knee joint
is actually a modified don't put that fibula in there it's a little too wide so the knee joint is
actually a modified hinge joint and lastly pivot joints this will be the six so i kind of miss
forgot to keep numbering them so the pivot joint is will be our sixth synovial or type of synovial
joint and will have a rounded or pointed articular surface articulating with a more ring-like other
articular surface or ring-like bone and these are uniaxial as well because you only have movement
or rotation around a bone's own longitudinal axis so the atlantoaxial joint which is located between
the first cervical vertebrae and the second cervical vertebrae around this region here this
is an excellent example of a pivot joint so this is that joint that allows us to shake our head no
all right question time my favorite time the elbow joint is only capable of flexion and extension
what is the synovial joint type of this joint oh i like to say joint in this question stem
all right so what in this stem will help you answer this question
well what's kind of j you know kind of jutting out to me right from the get-go is elbow joint
and only capable of flexion and extension all right so those are kind of the two main clues or
what will help i think most in answering this question and really only one of these answer
choices matches these two descriptors here which is what yes c hinge joint very good very good
for each individual joint we discuss in upcoming videos we will talk about
what type of joint it is so review here but keep in mind we will discuss again for sure
these different types of joints thank you for your time and attention here and have a great day