joints can be classified structurally based on their anatomical characteristics and functionally based on the type of movement that they permit the structural classification of joints is based on two criteria the presence or the absence of a space between the articulating Bones called a cial cavity which is this part here with the articulating bones being this one here and here and then the type of connective tissue that binds the bones together using this structural classification joints are classified as one of three types A fibrous joint which has no sovial cavity and the bones are held together by dense irregular connective tissue a cartilaginous joint which also has no noal cavity and the bones are held together by cage and ovial Joint which does contain a sovial cavity and the bones of the joint are connected by dense irregular connective tissue of an articular capsule also known as a joint capsule and is this fibrous structure we see on either side here now the functional classification of joints relates to the degree of movement that that joint permits functionally joints are also classified as one of three types we have a fine arthrosis which is a joint that is immovable an ampy arthrosis which is a joint that is slightly movable and a DI arthrosis which is a joint that is freely movable now for the remainder of this module we will focus on the structural classification of joints however each joint will have both a structural and a functional classification so starting with our fibrous joints and a fibrous joint Lacks aob cavity and the articulating bones are held really closely together by dense irregular connective tissue fibrous joints permit little to no movement so are also classified functionally as an amphi or as arthrosis and there are three different types of fibrous joints these are sutes syndesmosis and interus membranes so a suture is a fibrous joint composed of a th layer of dense irregular connective tissue sutures only occur between the bones of the skull The Irregular interlocking edges of a suture give them added strength and decrease their chance of fracturing in older individuals sutures are immovable or sin arthrosis but in infants and children they are slightly movable or ampy arthrosis which is really important for as long as their heads and their brains are still growing so a suture is this structure here you can see that a regular Edge along here and in a slightly zoomed in image of a a suture and a child this is that suture here a synos mosis is a fibrous joint in which there is a greater distance between the articulating surfaces so those two bones and more dense irregular connective tissue surrounds the joint than in a suture the connective tissue is typically arranged as a bundle in the form of a ligament which limits the amount of movement at that joint an example of a cmosis is the distal tibio fibular joint which is where the anterior tibio fibula ligament connects the tibia which is this thick bone here to the fibula which is the thinner bone here this is in our lower leg here it permits slight movement at the ankle and so is hence also described as an amphi arthrosis another example is called a gumus which is the joint between a tooth and the respective Jawbone in healthy teeth this joint permits no movement an interus membrane is a large sheet of dense irregular connective tissue which binds neighboring long bones and permits very small amounts of movement there are two main interus membrane joints in the human body one occurs between the radius and the Ona which are the two bones in our lower arm the other occurs between the tibia sorry tibia and our fibula in the lower leg so this is our interus membrane here