PHYT 622 Clinical Gross Anatomy Overview of the course z z z z Introduction z z z Let s Get Started Staff Lectures Days Times Locations Labs Types Days Times Locations Texts Cadavers Assignments to dissection groups Exams Format Schedule Lecture One Connective Tissue z z Supporting Tissues of the body e g fascia areolar ligaments joint capsules tendons and the modified CT such as cartilage and bone In general Does not form an organ or organ system CT General Continued z z z CT is essential to the structure and function of other tissues and organs Without it organs would collapse and be shapeless and would lack vital protection Without CT the body would be a quivering mass of protoplasm although it does form a significant portion of the skeletal system The most widely distributed and fundamental tissue and is found everywhere CT General Continued z Specific Functions Binds structures together Supports structures where rigidity is called for Protects organs with sheaths or capsules or when necessary bones or cartilage Partitions parts of the body Unites dissimilar tissue such as muscle bone Fills the empty spaces of the body Provides the framework throughout the body which vessels and nerves may proceed to their respective destinations 1 General Continued z z z You will treat more CT injuries than any other soft tissue From fascia to tendons to ligaments to joint capsules Type location density etc will dictate type of treatment Germ Layers Origin of CT z z Ectoderm Mesoderm Endoderm Mesoderm z z z z Mesoderm Continued z z z Develops in mesodermal germ layer along with muscle and bone Overview of three germ layers Comprised of primitive cells called mesenchyme In the embryo is a mass of unspecialized cells Supports embryo much in the way it will support body in later life As embryo increases in size and shape changes mesenchyme can not complete function needs more support Stem Cells At this point specialization of cells begins to occur Cells are genetically programmed to develop into specific type of CT A mass of undifferentiated cells begins to develop into specific types of CT Some cells remain dormant develop later when needed remain programmed 2 CT Components Components of CT z z All CT made up of same components percentage or arrangement of components depends on function of CT Components are CT cells fibers and intercellular medium AKA matrix From The Mesenchyme CT Cells z z Cells and Fibers Fibroblasts fiber forming Predominant cell fibers evolve and give each type of CT its specific structure Other cells are typical cells found anywhere like fat cells WBC pigmenting cells and macrophages CT Fibers z z The outstanding characteristic of CT and are directly concerned with function Collagen makes up 80 of CT Collagenous fibers made from several types of protein collagen Primarily Type I Found where strength and support is needed or where a firm union is required e g ligaments have lots of collagen Collagenoses familial disease is a disease characterized by the destruction of collagen 3 My Babies CT Fibers Continued z z z z z Elastic fibers made from protein elastin Not rigid and un yielding are elastic in nature Found where flexibility is needed Around vital organs these change in size and volume need support but not rigidity Can be found in ligaments where more flexibility is needed Matrix z z z z Types of Collagen z 1 Type I Found in tendons ligaments and stratum fibrosum 70 80 of dry weight z 2 Type II Found in hyaline cartilage and annulus fibrosis z 3 Type III Skin and stratum synovium z 4 Type XI Articular cartilage CT Fibers Continued z z z Reticular fibers made from protein reticulin Form a delicate network of supporting structures around individual cells or portions of some organs The fine mesh of CT around blood vessels and nerves would be a good example Matrix AKA intercellular medium ground substance Made up of carbohydrates proteins salts glycosaminoglygen GAG and water Up to 20 H20 Varies in consistency Some CT like ligaments cartilage and bone requires a dense or firm matrix for strength 4 Matrix Types of CT z z Matrix Types of CT Two Broad categories Loose and Dense Loose Has all the components of CT but matrix is soft Found where packing or anchoring material is necessary not extreme strength E G mesenchyme of embryo loose areolar and adipos Dense CT z z Loose CT I E Areolar Three varieties irregularly arranged regularly arranged and elastic tissue Irregularly arranged Stronger than loose more collagen I E fascia Telesubcutanea or superficial fascia plantar fascia etc Also capsules perichondrium periosteum 5 Regularly Arranged CT z z Ligaments aponeuroses tendons Ligaments Essentially unite bone to bone not that simple Made up of closely packed Type I collagenous fibers arranged nearly in parallel manner to give tensile strength Arrangement of Collagen Fibers 1 Less parallel in ligaments to allow these structures to sustain predominant tensile strength in one direction and smaller stresses in other directions 2 Nearly parallel in tendons to allow them to withstand high unidirectional loads Ligaments Continued z z Ligaments Continued Two Layers of Joint capsule stratum fibrosum and stratum synovium Stratum Fibrosum Outer layer Formed from tough fibrous CT Anchored to bone via Sharpey s fibers Poor vascularization rich in nerve supply especially paint temp position sense proprioception joint position speed of movement etc Relatively inelastic main role is to restrict and guide Joint Capsule z z z Ligaments are expansions of the synovial joint capsule AKA fibrous joint capsule Surround all freely moveable or synovial joints AKA diarthrodial joints Joint capsule can be thought of as an envelope that encapsulates an entire joint The space between joints is called the joint space or cavity Ligaments Continued z Stratum Synovium Inner layer Referred to as synovial membrane Rich in blood supply poorly innervated Manufactures synovial fluid aka hyaluronic acid clear pale yellow does not clot fairly sparse in most joints hemarthrosis Essential in nutrition of joint especially cartilage Lubricates joint has a viscosity viscosity decreases with as joint movement increase increases as joint movement decreases also temperature dependent synovitis Jt Capsule Cont 6 Priorities Ligaments Continued z z z z z Tendons z z 2 Transmit tensile loads from muscle to bone thereby producing joint motion z 3 Forces transmitted with relatively little loss of force Tendons Continued z z z