We will discuss types of movements at synovial joints. Remember that synovial joints are freely movable, which means they are diarthritic. And the types of movements that can occur at synovial joints are going to depend on different factors.
One of the major factors is the articulation of the two bones. So what are the shapes of the two bones that meet? So remember we have six types of synovial joints.
Planar, hinge, pivot, condyloid, saddle, and ball and socket. Based on how these bones fit together is going to determine some of their movement. Other factors that determine the movement that occurs at synovial joints is going to be the arrangement of ligaments and tendons, the muscle tension, hormone production in your body, and apposition coming together of soft spots. This use also plays a factor in the range of motion. So the first movement will be a special movement.
This means that these movements, it's not the type of joint they're occurring at within a synovial joint, it's just special joints. So this is not going to be specifically ball and socket, planar, hinge. It just means it's only found in certain joints in the body. So protraction and retraction. I want everyone to actually do these movements as we go through.
In protraction, it's like you're pouting. You're sticking your lower jaw out past your teeth, so it's almost like a bad underbite. And then retraction is pulling the jaw back and basically forming an overbite. However, it doesn't just occur at your TMJ, your temporomandibular joint.
It also occurs at your shoulders. Protraction would be like rolling your shoulders forward. Retraction will be rolling your shoulders back. Next is going to be angular movements.
These are movements that are going to open or close the angle at a joint. The first few we're going to go over are flexion, extension, and hyperextension. And these can happen at many joints in the body. Flexion is going to be closing the angle.
Extension is going to be opening the angle. Hyperextension is going past. the normal plane.
So we can see flexion would be bending your neck forward so your chin touches your chest. Extension is bringing your head back to a upright position and hyperextension would be leaning it back looking up at the sky. This also happens with arm. If you bring your arm straight forward and keeping it straight with your palm up in a supine position, This is flexion, bringing the arm back so it just sits at your side would be extension. But pulling your arm back past your back is hyperextension.
If you're doing biceps curls where you close your elbow towards your chest, extension. Put your elbow back to where your arm is straight is extension. Sorry, I said flexion.
It should have been flexion when you do bicep curls. When you release your arm and it's... Straight that's extension and some people do have the ability to hyper extend at their elbow joint If you're at your wrist and you close your wrist towards your elbows, that's Flexion if you put your wrist out straight where your palm is flat with your arm is extension But if you open your wrist to where the back of your palm is getting closer to your elbow that is hyper extension This occurs with your leg. If you kick your leg forward, think about the Rockettes or any kick line. Dallas Cowboy Cheerleaders, the Saints, when they kick their leg forward, it is flexion.
When they pull their leg back to a normal position, such as standing, that's extension. But if you kick your leg back, like you're almost doing gluteal maximus extensions on the machines, that's hyperextension. This also occurs at your knee joint. If you're sitting down on a chair and you're swinging your knee forward and straightening your leg, that's going to be extension. But when you bring your foot, your knee back and you do it to a 90 degree bend, that's going to be flexion because you're closing the angle.
Abduction and adduction. Think about what these words mean. Ad means we're coming together.
So when you add numbers, you add them together. That's what adduction means. So it's coming together.
towards the midline abduction a b means you're going away from the midline so if you bring your arms away like you're doing a jumping jack up to an x that's abduction but when you bring your arms back towards your body and put them by your side that is adduction you can do this with your wrist if you take your wrist and you're in anatomical position And you put your wrist towards your body, adduction. If you put your wrist away from your body, abduction. Same with your fingers. Open your fingers like a web, like gecko's feet, abduction.
Put your fingers back together, adduction. Same thing with your legs. Again, think about jumping jacks. If you're up in that X position, going away from your body, abduction. Bringing the leg back towards the midline.
adduction. Another angular movement is circumduction. This means it's a circular movement. You can do this with your shoulder and your hip. So it's basically going in big circles.
Rotation is going to be on its own axis. So you can do rotations at different spots. In your neck, you can turn left and right with your head. That's going to be rotation of the elanto-occipital joint.
You can also do it with your arm. You can go towards your body with your elbow and make your forearm go across your body, or you can bring your forearm away from your body, keeping your elbow at the side. You can also do this with your leg.
If your leg is in correct anatomical position, which means feet forward, so this leg is in correct anatomical position, if you turn the foot outward, that's lateral. If you turn the foot inward like pigeon toes, that's medial rotation. Elevation and depression.
This is another special movement that is only going to occur at certain joints in the body, not types of synovial joints. Elevation would be closing your mouth. Depression would be dropping your jaw like you're in shock. This also happens with your shoulder, not just your TMJ joint.
Elevation is shrugging your shoulders up like what's going on. Depression is dropping your shoulders down like you're defeated. Inversion and eversion are also special movements because they only occur at the ankle joint.
If you roll your ankle and you make your big toe face your crotch, that's inversion. If you roll your ankle and make the pinky face the sky, that's eversion. Eversion means going out. Inversion means facing in. Dorsiflexion and plantarflexion.
If you stand on your tippy toes, like you're trying to reach something, you're doing plantarflexion. If you walk on your heels and the top of your foot is getting closer to your shin, dorsiflexion. Pronation and supination. This is actually going to be not your elbow joint, but your radial ulnar joint where the radius and ulna meet together.
This is a pivot joint. And if you have your body in correct anatomical position, that means your palms are facing forward. This is supination.
Easy way to think about this is that you can carry soup with your palms facing up, but you can't carry soup with your palms facing back. So palms forward, supination. Palms back is going to be pronation.
Opposition is when your thumb touches any of your fingers and you kind of form the letter O. So if you're telling someone A-OK and your thumb touches your forefinger or your index finger, that's opposition. If your thumb touches your middle finger, that's opposition.
Your ring finger, that's opposition. And your pinky finger, that's opposition. So we're going to watch a quick little video on synovial joint movements.
I am keeping a session for your site. This is a video of a student who was in a car accident. The student was in a car accident.
The student was in a car accident. The student was in a car accident. The student was in a car accident. So, hey, I don't know what happened to that one.
You know, right? I don't know. I don't know.
I don't know. I don't know. I don't know.
I don't know. I don't know. I don't know. I don't know.
I don't know. I don't know. I don't know.
I don't know. I don't know. I don't know. I don't know.
I don't know. I don't know. I don't know.
I don't know. I don't know. I don't know.
I don't know. I don't know. I don't know. I don't know.
I don't know. I don't know. I don't know.