Labs 6/7 – and IUSM – 2016

I. Introduction Cartilage and Bone II. Learning Objectives III. Keywords IV. Slides A. Cartilage 1. Hyaline 2. Elastic 3. Fibrocartilage B. Bone 1. General Overview 2. Formation and Growth a. Intramembranous formation b. Endochondral formation c. Appositional growth d. Internal remodeling 3. Types a. Woven b. Lamellar i. Cancellous/Trabecular ii. Cortical/Compact C. 1. Synovial 2. Intervertebral SEM of trabecular/cancellous bone. Inserm. V. Summary Labs 6/7 – Cartilage and Bone IUSM – 2016 Cartilage and Bone I. Introduction II. Learning Objectives 1. Cartilage is a specialized type of solid connective tissue III. Keywords which, along with bone, is distinguished by the relative IV. Slides rigidity of its (ECM); it is easily A. Cartilage distinguishable from bone by its avascularity; it provides 1. Hyaline flexible support to tissues (e.g., ear, nose, larynx). 2. Elastic 2. Types of cartilage (hyaline, elastic, and fibrocartilage) are 3. Fibrocartilage distinguished by the characteristics of their respective B. Bone ECM (e.g., the dominant type of fiber). 1. General Overview 2. Formation and Growth 3. Bone is a specialized type of solid connective tissue characterized by a mineralized ECM that stores calcium a. Intramembranous formation and phosphate. b. Endochondral formation c. Appositional growth 4. Woven bone (immature) differs from lamellar bone d. Internal remodeling (mature) in its collagen fiber arrangement; all new bone 3. Types is woven, but it becomes remodeled into lamellar bone, a. Woven with few exceptions. b. Lamellar 5. Lamellar bone has organized ECM sheets (lamellae); the i. Cancellous/Trabecular dense bone that forms the outer cortex of most of ii. Cortical/Compact the body is referred to as cortical bone; while the less- C. Joints dense, inner bone which is not as compacted but instead 1. Synovial arranged in a lattice-like configuration is referred to as 2. Intervertebral cancellous bone. V. Summary Labs 6/7 – Cartilage and Bone IUSM – 2016

I. Introduction II. Learning Objectives Bone Formation and Joints III. Keywords IV. Slides 1. Bone formation occurs via two basic mechanisms: A. Cartilage a. Intramembranous forms bone 1. Hyaline within mesenchyme (“membrane”). 2. Elastic 3. Fibrocartilage b. Endochondral ossification forms bone by B. Bone replacing a cartilage model. 1. General Overview 2. Regardless of the mechanism, all new bone is woven 2. Formation and Growth bone which is remodeled into lamellar bone (either a. Intramembranous formation compact or trabecular), with organized sheets of bone b. Endochondral formation (lamellae), by and activity. c. Appositional growth d. Internal remodeling 3. Joints are places where bones meet (articulate), 3. Types allowing at least the potential of bending or movement; examples include synovial joints (diarthrosis) and a. Woven intervertebral joints. b. Lamellar i. Cancellous/Trabecular ii. Cortical/Compact C. Joints 1. Synovial 2. Intervertebral V. Summary Labs 6/7 – Cartilage and Bone IUSM – 2016

I. Introduction II. Learning Objectives Learning Objectives I – Cartilage and Bone III. Keywords IV. Slides 1. Understand the variations in structure and function of the three major A. Cartilage types of cartilage, with regard to both the cellular and extracellular 1. Hyaline elements. 2. Elastic 3. Fibrocartilage 2. Understand the key ultrastructural features of the and how B. Bone they relate to function. 1. General Overview 2. Formation and Growth 3. Understand the structural features and functions of osteogenic cells: a. Intramembranous formation , , and . b. Endochondral formation c. Appositional growth 4. Know the major differences in structure and function between woven and d. Internal remodeling lamellar bone, and between compact and cancellous bone. 3. Types a. Woven b. Lamellar 5. Understand the structure and composition of an and how it is i. Cancellous/Trabecular formed. ii. Cortical/Compact C. Joints 1. Synovial 2. Intervertebral V. Summary Labs 6/7 – Cartilage and Bone IUSM – 2016

I. Introduction II. Learning Objectives Learning Objectives II – Bone Formation and Joints III. Keywords IV. Slides 1. Understand the differences and similarities between intramembranous A. Cartilage and endochondral bone formation and the key function of the 1. Hyaline in bone growth. 2. Elastic 3. Fibrocartilage 2. Understand the organization of the epiphyseal growth plate and its role in B. Bone endochondral bone formation and growth of long bones. 1. General Overview 2. Formation and Growth 3. Understand the structure of a typical synovial , including the nature a. Intramembranous formation and functions of the synovium. b. Endochondral formation c. Appositional growth d. Internal remodeling 3. Types a. Woven b. Lamellar i. Cancellous/Trabecular ii. Cortical/Compact C. Joints 1. Synovial 2. Intervertebral V. Summary Labs 6/7 – Cartilage and Bone IUSM – 2016 Keywords I. Introduction II. Learning Objectives III. Keywords Articular cartilage Lacunae IV. Slides Bone Lamellae A. Cartilage Canaliculi Lamellar bone 1. Hyaline Cancellous 2. Osteoblast 3. Fibrocartilage Central (Haversian) canal Osteoclasts B. Bone 1. General Overview Compact bone Osteon 2. Formation and Growth Elastic cartilage Perforating (Volkmann’s) canal a. Intramembranous formation Endochondral ossification b. Endochondral formation Periosteum c. Appositional growth Fibrocartilage d. Internal remodeling Growth plate Synovium 3. Types Haversian system Trabeculae a. Woven Howship’s lacunae Woven bone b. Lamellar Zone of calcification Intervertebral joint Zone of hypertrophy i. Cancellous/Trabecular Interstitial lamellae Zone of osteogenesis ii. Cortical/Compact Intramembranous ossification Zone of proliferation C. Joints Joint Zone of reserve cartilage 1. Synovial 2. Intervertebral V. Summary Labs 6/7 – Cartilage and Bone IUSM – 2016

I. Introduction Slide 2: Trachea, Trichrome II. Learning Objectives III. Keywords IV. Slides A. Cartilage thyroid gland 1. Hyaline 2. Elastic 3. Fibrocartilage B. Bone perichondrium 1. General Overview 2. Formation and Growth look here for a. Intramembranous formation hyaline cartilage b. Endochondral formation lumen c. Appositional growth d. Internal remodeling 3. Types a. Woven b. Lamellar what kind of i. Cancellous/Trabecular epithelium lines the ii. Cortical/Compact lumen of the trachea? C. Joints 1. Synovial 2. Intervertebral V. Summary Labs 6/7 – Cartilage and Bone IUSM – 2016

I. Introduction Slide 2: Trachea, Trichrome II. Learning Objectives III. Keywords IV. Slides A. Cartilage 1. Hyaline 2. Elastic hyaline 3. Fibrocartilage cartilage B. Bone 1. General Overview 2. Formation and Growth a. Intramembranous formation b. Endochondral formation c. Appositional growth d. Internal remodeling 3. Types perichondrium a. Woven peri = “around” b. Lamellar chondrium = “cartilage” i. Cancellous/Trabecular ii. Cortical/Compact C. Joints 1. Synovial (Gr. “glassy”) is the most common type of cartilage in the body; it contains the smallest 2. Intervertebral hyaline cartilage proportion of fibers in the ECM (primarily type II collagen), giving it a fairly homogenous, glassy appearance V. Summary Labs 6/7 – Cartilage and Bone IUSM – 2016

I. Introduction Slide 2: Trachea, Trichrome II. Learning Objectives III. Keywords IV. Slides perichondrium A. Cartilage fibroblast 1. Hyaline 2. Elastic chondroblast 3. Fibrocartilage B. Bone 1. General Overview 2. Formation and Growth a. Intramembranous formation hyaline cartilage b. Endochondral formation c. Appositional growth notice the lack of vasculature d. Internal remodeling within the cartilage; it relies on diffusion from vessels in the 3. Types perichondrium, limiting the a. Woven maximal cartilage thickness b. Lamellar i. Cancellous/Trabecular ii. Cortical/Compact C. Joints is dense regular CT essential for appositional growth and maintenance of cartilage; it consists 1. Synovial perichondrium largely of , fibroblasts, and progenitor cells for chondroblasts that divide and differentiate into 2. Intervertebral chondrocytes; hyaline cartilage is three-dimensionally surrounded by perichondrium, expect as articular V. Summary cartilage in joints; elastic cartilage also has perichondrium, but fibrocartilage does not Labs 6/7 – Cartilage and Bone IUSM – 2016

I. Introduction Slide 2: Trachea, Trichrome II. Learning Objectives III. Keywords cartilage hyaline IV. Slides A. Cartilage 1. Hyaline

2. Elastic perichondrium 3. Fibrocartilage B. Bone chondrocyte (cell) located in (space) 1. General Overview 2. Formation and Growth a. Intramembranous formation chondroblast b. Endochondral formation c. Appositional growth d. Internal remodeling fibroblast 3. Types a. Woven b. Lamellar appositional growth occurs at the interface of the perichondrium and the cartilage as chondroblasts, from i. Cancellous/Trabecular perichondrial cells, actively synthesize new cartilage matrix; they secrete ECM components until they encase ii. Cortical/Compact themselves within the matrix – the small remaining, matrix-free space that the cell inhabits is called a lacuna C. Joints (Lt. “little lake”); once encased, the cells are referred to as chondrocytes, which continue to synthesize and 1. Synovial maintain ECM components; both types of cells have basophilic cytoplasm rich in rER for collagen synthesis 2. Intervertebral terminology note: the suffix –blast identifies immature, not fully-differentiated cell types; those cells differentiate V. Summary into mature, terminal cells identified by the suffix –cyte; fibroblasts are a slight exception to this rule, as the term fibrocyte is seldom used and has been newly applied to types of circulating mesenchymal progenitor cells Labs 6/7 – Cartilage and Bone IUSM – 2016

I. Introduction Slide 140: Trachea, H&E II. Learning Objectives III. Keywords IV. Slides A. Cartilage perichondrium 1. Hyaline 2. Elastic 3. Fibrocartilage B. Bone 1. General Overview the empty appearance of 2. Formation and Growth some lacunae is an artifact of a. Intramembranous formation slide preparation, as the cells

cartilage hyaline either pull away from the b. Endochondral formation matrix or are lost c. Appositional growth d. Internal remodeling small clusters of 3. Types chondrocytes are referred a. Woven to as isogenous groups and b. Lamellar reflect interstitial growth i. Cancellous/Trabecular ii. Cortical/Compact C. Joints lighter-staining interterritorial matrix is darker-staining territorial matrix 1. Synovial located between groups of chondrocytes surrounds isogenous groups 2. Intervertebral and reflects concentration differences in V. Summary ECM components Labs 6/7 – Cartilage and Bone IUSM – 2016

I. Introduction Slide 87: Epiglottis, Masson AF II. Learning Objectives III. Keywords IV. Slides elastic cartilage A. Cartilage 1. Hyaline perichondrium 2. Elastic 3. Fibrocartilage lamina propria B. Bone (loose CT) 1. General Overview 2. Formation and Growth a. Intramembranous formation b. Endochondral formation non-keratinzed c. Appositional growth stratified squamous d. Internal remodeling epithelium 3. Types a. Woven b. Lamellar i. Cancellous/Trabecular ii. Cortical/Compact C. Joints the epiglottis (protects entrance to larynx) consists of a core of elastic cartilage surrounded by loose CT and a 1. Synovial covering of stratified squamous epithelium; elastic cartilage is similar to hyaline cartilage except that it contains 2. Intervertebral an abundant network of elastic fibers in addition to type II collagen; visualization of the elastic fibers usually V. Summary requires special stains; it is found in the auricle of the ear, walls of the external auditory canals (auditory meatus), auditory (Eustachian) tubes, epiglottis, and in the larynx Labs 6/7 – Cartilage and Bone IUSM – 2016

I. Introduction Slide 56: Elastic Cartilage, AF II. Learning Objectives III. Keywords IV. Slides A. Cartilage 1. Hyaline 2. Elastic 3. Fibrocartilage B. Bone perichondrium 1. General Overview

2. Formation and Growth elastic cartilage a. Intramembranous formation b. Endochondral formation c. Appositional growth d. Internal remodeling 3. Types a. Woven b. Lamellar the separation of the i. Cancellous/Trabecular tissue is an artifact of ii. Cortical/Compact slide preparation C. Joints 1. Synovial 2. Intervertebral V. Summary Labs 6/7 – Cartilage and Bone IUSM – 2016

I. Introduction Slide 25: Auditory Meatus, H&E II. Learning Objectives Slide Overview III. Keywords IV. Slides keratinized stratified A. Cartilage squamous epithelium 1. Hyaline

2. Elastic skin hair follicle 3. Fibrocartilage B. Bone sebaceous gland 1. General Overview 2. Formation and Growth ceruminous (earwax) a. Intramembranous formation gland b. Endochondral formation c. Appositional growth d. Internal remodeling perichondrium 3. Types a. Woven elastic cartilage b. Lamellar i. Cancellous/Trabecular ii. Cortical/Compact C. Joints 1. Synovial distinguishing elastic cartilage from hyaline cartilage can be tricky in H&E without specialized stains to show 2. Intervertebral the elastic fibers; however: the elastic fibers provide a more heterogeneous appearance to the cartilage vs. the V. Summary smooth, glassy appearance of hyaline; elastic cartilage has a greater density of chondrocytes with less ECM between them than in hyaline; and the chondrocytes in elastic cartilage tend to be larger than in hyaline Labs 6/7 – Cartilage and Bone IUSM – 2016

I. Introduction Slide 131: Fibrocartilage, H&E II. Learning Objectives Slide Overview III. Keywords IV. Slides A. Cartilage skeletal muscle 1. Hyaline 2. Elastic periosteum 3. Fibrocartilage cortical bone B. Bone 1. General Overview bone marrow within 2. Formation and Growth trabecular bone a. Intramembranous formation adipocytes b. Endochondral formation c. Appositional growth endochondral ossification d. Internal remodeling adipocytes 3. Types a. Woven skeletal muscle b. Lamellar i. Cancellous/Trabecular attachment of ii. Cortical/Compact muscle to the bone C. Joints 1. Synovial 2. Intervertebral the slide shows the pubic , which is the linking the pubic bones of the pelvic girdle; V. Summary beyond the fibrocartilage, examples of many other tissue types and structures can be identified Labs 6/7 – Cartilage and Bone IUSM – 2016

I. Introduction Slide 131: Fibrocartilage, H&E II. Learning Objectives III. Keywords IV. Slides A. Cartilage 1. Hyaline 2. Elastic 3. Fibrocartilage B. Bone chondrocyte 1. General Overview in lacuna 2. Formation and Growth a. Intramembranous formation collagen b. Endochondral formation bundle c. Appositional growth d. Internal remodeling fibroblast 3. Types a. Woven b. Lamellar i. Cancellous/Trabecular ii. Cortical/Compact C. Joints fibrocartilage is a combination of dense regular CT (type I collagen) and hyaline cartilage (type II collagen); 1. Synovial the collagen bundles and chondrocytes are generally arranged in rows parallel to the direction of functional 2. Intervertebral stress; unlike hyaline and elastic cartilage, there is no distinct surrounding perichondrium in fibrocartilage; it V. Summary is found in intervertebral discs, attachments of certain , and in the Labs 6/7 – Cartilage and Bone IUSM – 2016 Slide 34: Bone, H&E Slide Overview I. Introduction II. Learning Objectives III. Keywords callus IV. Slides A. Cartilage 1. Hyaline 2. Elastic 3. Fibrocartilage B. Bone 1. General Overview 1 2. Formation and Growth cortical a. Intramembranous formation bone b. Endochondral formation c. Appositional growth fracture d. Internal remodeling 3. Types a. Woven EC Oss b. Lamellar 2 hyaline cartilage i. Cancellous/Trabecular trabecular ii. Cortical/Compact bone C. Joints 1. Synovial and are two rib segments from a fetal/newborn rabbit; gives an example of a bone fracture 2. Intervertebral sections (1) (2) (1) and repair processes (the callus is a temporary formation of highly proliferative fibroblasts and chondroblasts V. Summary extending from the periosteum down into the fracture to form new bone); (2) gives an example of endochondral ossification (EC Oss) bone growth Labs 6/7 – Cartilage and Bone IUSM – 2016 Slide 34: Bone, H&E Slide Overview I. Introduction II. Learning Objectives III. Keywords IV. Slides P A. Cartilage 1. Hyaline Act P 2. Elastic 3. Fibrocartilage B. Bone HC 1. General Overview 2. Formation and Growth a. Intramembranous formation Wb b. Endochondral formation c. Appositional growth M d. Internal remodeling M 3. Types Tb a. Woven b. Lamellar i. Cancellous/Trabecular ii. Cortical/Compact C. Joints from the outside: (P) is periosteum, the dense connective tissue surrounding bone, with clearly visible collagen 1. Synovial bundles; (Act P) is an area of more active periosteum with lots of cellular differentiation occurring; (Wb) is 2. Intervertebral woven or ; (HC) are areas of hyaline cartilage; (M) is marrow with abundant blood cells; (Tb) is V. Summary mature, lamellar trabecular bone; close examination shows endosteum on the edge of the bone bordering the marrow Labs 6/7 – Cartilage and Bone IUSM – 2016 Slide 34: Bone, H&E Slide Overview I. Introduction II. Learning Objectives III. Keywords P IV. Slides Cb A. Cartilage 1. Hyaline 2. Elastic M 3. Fibrocartilage B. Bone Tb 1. General Overview 2. Formation and Growth a. Intramembranous formation b. Endochondral formation c. Appositional growth d. Internal remodeling 3. Types Tb P a. Woven Wb b. Lamellar i. Cancellous/Trabecular ii. Cortical/Compact C. Joints 1. Synovial from the outside (top): (P) is periosteum with clearly visible collagen bundles; (Cb) is cortical bone with a 2. Intervertebral lamellar arrangement of bone matrix and ; (M) is marrow with abundant blood cells; (Tb) is trabecular bone with endosteum on the edge of the bone bordering the marrow; is woven or primary bone which is V. Summary (Wb) newly-formed bone with an irregular arrangement of collagen fibers (i.e., not lamellar) Labs 6/7 – Cartilage and Bone IUSM – 2016 Slide 34: Bone, H&E I. Introduction Slide Overview II. Learning Objectives III. Keywords periosteum IV. Slides (dense regular CT) A. Cartilage 1. Hyaline peri = “around” osteum = “bone” 2. Elastic 3. Fibrocartilage B. Bone fibroblast 1. General Overview 2. Formation and Growth a. Intramembranous formation osteoprogenitor cells b. Endochondral formation (osteoblasts) c. Appositional growth d. Internal remodeling 3. Types osteocyte in lacuna a. Woven b. Lamellar i. Cancellous/Trabecular ii. Cortical/Compact C. Joints 1. Synovial periosteum is dense regular CT that surrounds the outer surfaces of bone (except at articulations) and attaches 2. Intervertebral to the outer lamellae via collagenous Sharpey’s fibers (not always seen); it contains osteoprogenitor cells which are capable of differentiating into osteoblasts and forming new bone (appositional growth); blood vessels pass V. Summary between the periosteum and bone through perforating (Volkmann’s) canals, with most blood directionally flowing from the marrow cavities and draining out through periosteal veins Labs 6/7 – Cartilage and Bone IUSM – 2016 Slide 34: Bone, H&E I. Introduction Slide Overview II. Learning Objectives III. Keywords IV. Slides endosteum trabecular bone A. Cartilage stroma of 1. Hyaline bone marrow 2. Elastic 3. Fibrocartilage red blood cells in B. Bone vascular sinusoid 1. General Overview how new blood cells 2. Formation and Growth leave the marrow a. Intramembranous formation

b. Endochondral formation marrow hematopoietic cord

c. Appositional growth cavity where blood cell d. Internal remodeling development occurs - 3. Types filled a. Woven endosteum b. Lamellar i. Cancellous/Trabecular osteocyte (cell) ii. Cortical/Compact trabecular bone in lacuna (space) C. Joints 1. Synovial endosteum lines all the internal surfaces of bone (marrow cavities, osteons, and perforating canals); it is 2. Intervertebral generally only a single cell-layer thick and consists of osteoblasts and bone-lining cells; inactive osteoblasts V. Summary and bone-lining cells are generally flattened with only dark, elongated nuclei being visible; osteoblasts that are actively secreting bone ECM components are much more round or cuboidal in appearance Labs 6/7 – Cartilage and Bone IUSM – 2016 Slide 34: Bone, H&E I. Introduction Slide Overview II. Learning Objectives III. Keywords IV. Slides marrow A. Cartilage 1. Hyaline 2. Elastic 3. Fibrocartilage B. Bone endosteum with osteoblasts (round, plump cells) 1. General Overview 2. Formation and Growth a. Intramembranous formation osteoid b. Endochondral formation lighter-stained area between c. Appositional growth endosteum and mature bone d. Internal remodeling 3. Types a. Woven osteocyte in lacuna b. Lamellar trabecular bone i. Cancellous/Trabecular ii. Cortical/Compact C. Joints 1. Synovial osteoid is the collagen-rich, non-mineralized precursor to true bone ECM; it is secreted by osteoblasts, such as 2. Intervertebral those of the endosteum, during bone growth, repair, and remodeling; the osteoblasts subsequently calcify the V. Summary osteoid into hard bone matrix, and in the process, they become trapped in the matrix (in lacunae) and become osteocytes (similar to the process of chondroblasts becoming chondrocytes in cartilage) Labs 6/7 – Cartilage and Bone IUSM – 2016 Slide 34: Bone, H&E I. Introduction Slide Overview II. Learning Objectives III. Keywords IV. Slides A. Cartilage 1. Hyaline 2. Elastic 3. Fibrocartilage B. Bone 1. General Overview 2. Formation and Growth a. Intramembranous formation b. Endochondral formation c. Appositional growth d. Internal remodeling 3. Types a. Woven osteoclast within Howship’s lacuna b. Lamellar osteoclast within Howship’s lacuna i. Cancellous/Trabecular ii. Cortical/Compact osteoclasts (Gr. “bone breaking”) are large, acidophilic, multinucleated cells (generally 5-20 nuclei); they are C. Joints critical for bone remodeling and resorb bone by secreting organic acids which dissolve hydroxyapatite and 1. Synovial lysosomal enzymes which break down the osteoid matrix; at the bone surface, osteoclasts are found within 2. Intervertebral surface depressions caused by the resorption of bone called Howship's lacunae (or resorption bays) V. Summary Labs 6/7 – Cartilage and Bone IUSM – 2016

I. Introduction II. Learning Objectives III. Keywords Intramembranous Ossification IV. Slides A. Cartilage 1. Hyaline 1. Primary center of ossification: mesenchyme cells  osteoblasts 2. Elastic 3. Fibrocartilage 2. Osteoblasts begin depositing bone matrix to form trabeculae or spicules B. Bone of woven bone (immature bone) extending radially from the ossification 1. General Overview center; osteoblasts become osteocytes 2. Formation and Growth 3. Marrow develops in spaces between trabeculae a. Intramembranous formation b. Endochondral formation 4. Periosteum and endosteum develop from mesenchyme membrane on c. Appositional growth surfaces of new bone d. Internal remodeling 3. Types 5. Woven bone is remodeled to form lamellar bone (compact and trabecular) a. Woven b. Lamellar i. Cancellous/Trabecular ii. Cortical/Compact C. Joints 1. Synovial 2. Intervertebral V. Summary Labs 6/7 – Cartilage and Bone IUSM – 2016 Slide 130: Fetal Skull I. Introduction Slide Overview II. Learning Objectives III. Keywords IV. Slides A. Cartilage 1. Hyaline 2. Elastic nasal cavity with 3. Fibrocartilage cartilaginous nasal septum in the middle; B. Bone surrounded by 1. General Overview intramembranous 2. Formation and Growth bone development of the skull a. Intramembranous formation b. Endochondral formation c. Appositional growth tongue in the d. Internal remodeling oral cavity 3. Types a. Woven b. Lamellar developing tooth Side View Frontal View i. Cancellous/Trabecular with surrounding intramembranous ii. Cortical/Compact bone development C. Joints see Slide 12a (464) and of the jaw 1. Synovial Slide 32 (NW) for additional examples 2. Intervertebral V. Summary Slide 130 – Fetal Skull Labs 6/7 – Cartilage and Bone IUSM – 2016

I. Introduction Slide 130: Fetal Skull II. Learning Objectives III. Keywords IV. Slides A. Cartilage 1. Hyaline 2. Elastic 3. Fibrocartilage trabeculae (or spiculae) B. Bone of new woven bone are 1. General Overview dispersed within 2. Formation and Growth mesenchyme a. Intramembranous formation look for osteoblasts on b. Endochondral formation the surfaces of the bone, c. Appositional growth while osteocytes can be d. Internal remodeling seen contained within the 3. Types lacunae of the bone a. Woven b. Lamellar i. Cancellous/Trabecular ii. Cortical/Compact C. Joints mesenchyme (primitive CT) 1. Synovial 2. Intervertebral V. Summary Labs 6/7 – Cartilage and Bone IUSM – 2016

I. Introduction Slide 130: Fetal Skull II. Learning Objectives III. Keywords IV. Slides A. Cartilage specialized 1. Hyaline olfactory 2. Elastic epithelium 3. Fibrocartilage B. Bone 1. General Overview 2. Formation and Growth trabeculae of a. Intramembranous formation woven bone hyaline b. Endochondral formation (new bone) cartilage c. Appositional growth d. Internal remodeling 3. Types a. Woven mesenchyme b. Lamellar periosteum i. Cancellous/Trabecular (dense CT) ii. Cortical/Compact C. Joints 1. Synovial 2. Intervertebral even though hyaline cartilage is present adjacent to the mesenchyme, it is not involved in the formation of V. Summary the new bone seen occurring here via intramembranous ossification (not endochondral ossification) Labs 6/7 – Cartilage and Bone IUSM – 2016 I. Introduction Endochondral Ossification II. Learning Objectives III. Keywords Unlike in intramembranous bone formation, endochondral ossification occurs when a hyaline cartilage IV. Slides model is replaced with bone; this more complex method of bone formation provides the benefit of having a A. Cartilage load-bearing structure in place (cartilage) before the bone has formed; the bones of the extremities and 1. Hyaline load-bearing bones of the axial (e.g., vertebrae) are formed via this method, which can be 2. Elastic spatiotemporally separated into the following zones: 3. Fibrocartilage B. Bone 1. Zone of Reserve Cartilage: hyaline cartilage acts as source of cartilage to 1. General Overview undergo ossification 2. Formation and Growth a. Intramembranous formation 2. Zone of Proliferation: normal chondrocytes multiply b. Endochondral formation 3. Zone of Hypertrophy: chondrocytes enlarge and align c. Appositional growth d. Internal remodeling 4. Zone of Calcification:* cartilage matrix calcifies providing scaffold for new 3. Types bone; chondrocyte degenerate (apoptosis) a. Woven b. Lamellar 5. Zone of Ossification and Resorption:* osteoblasts invade and bone is i. Cancellous/Trabecular deposited on the calcified matrix; osteoclasts begin the remodeling process ii. Cortical/Compact C. Joints Note: Because the rates of chondrocyte proliferation (in zone of proliferation) and destruction (in zone of 1. Synovial calcification) are approximately equal, the does not change in thickness; instead, it is 2. Intervertebral “displaced” away from the middle of the , resulting in growth in length of the bone. V. Summary Labs 6/7 – Cartilage and Bone IUSM – 2016 Slide 34: Bone, H&E I. Introduction II. Learning Objectives III. Keywords IV. Slides A. Cartilage 1. Hyaline 2. Elastic 3. Fibrocartilage B. Bone 1. General Overview 2. Formation and Growth marrow look here to see a. Intramembranous formation hyaline endochondral woven b. Endochondral formation cartilage ossification bone c. Appositional growth d. Internal remodeling 3. Types a. Woven b. Lamellar i. Cancellous/Trabecular ii. Cortical/Compact C. Joints epiphyseal growth plate diaphysis 1. Synovial (end of bone) (shaft of bone) 2. Intervertebral V. Summary Labs 6/7 – Cartilage and Bone IUSM – 2016 Slide 34: Bone, H&E I. Introduction II. Learning Objectives III. Keywords IV. Slides A. Cartilage 1. Hyaline 2. Elastic 3. Fibrocartilage B. Bone 1. General Overview 2. Formation and Growth a. Intramembranous formation b. Endochondral formation c. Appositional growth d. Internal remodeling 3. Types a. Woven b. Lamellar i. Cancellous/Trabecular zone of zone of zone of zones of ii. Cortical/Compact reserve cartilage proliferation hypertrophy calcification & ossification C. Joints 1. Synovial . typical hyaline cartilage . chondrocytes form rows or . chondrocytes . matrix becomes calcified clusters of cells from successive greatly enlarge in . chondrocytes degenerate 2. Intervertebral mitotic divisions size . osteogenic cells and vessels V. Summary invade from the bone marrow . osteoblasts form new bone Labs 6/7 – Cartilage and Bone IUSM – 2016 Slide 13 (464): Foot, H&E Slide 15a (464): Joint

I. Introduction primary II. Learning Objectives ossification centers III. Keywords IV. Slides A. Cartilage 1. Hyaline 2. Elastic 3. Fibrocartilage B. Bone 1. General Overview 2. Formation and Growth a. Intramembranous formation b. Endochondral formation Slide 13a (464): Bone, H&E Slide 42a (464): Fingertip c. Appositional growth d. Internal remodeling 3. Types a. Woven b. Lamellar i. Cancellous/Trabecular ii. Cortical/Compact i. Cortical/Compact ii. Cancellous/Trabecular C. Joints 1. Synovial 2. Intervertebral V. Summary Labs 6/7 – Cartilage and Bone IUSM – 2016 Slide 34: Bone, H&E I. Introduction II. Learning Objectives III. Keywords IV. Slides marrow A. Cartilage 1. Hyaline endosteum 2. Elastic 3. Fibrocartilage bone B. Bone osteoid (pale-staining) 1. General Overview 2. Formation and Growth osteoblasts a. Intramembranous formation b. Endochondral formation periosteum c. Appositional growth (dense CT) d. Internal remodeling 3. Types a. Woven b. Lamellar i. Cancellous/Trabecular ii. Cortical/Compact C. Joints while endochondral ossification provides a means for bones to lengthen at the epiphyseal growth plate, bones 1. Synovial grow wider (increase in diameter) via appositional growth at the interface between the bone and the 2. Intervertebral surrounding periosteum; osteoblasts differentiate from precursor cells and laydown new bone matrix (osteoid) V. Summary onto the surface of the bone, increasing the overall width; the marrow cavity then also enlarges by resorption of bone on the endosteal surface Labs 6/7 – Cartilage and Bone IUSM – 2016 Slide 104: Bone, H&E I. Introduction II. Learning Objectives III. Keywords periosteum IV. Slides A. Cartilage 1. Hyaline cortical bone 2. Elastic 3. Fibrocartilage resorption B. Bone canal 1. General Overview 2. Formation and Growth a. Intramembranous formation b. Endochondral formation osteon c. Appositional growth d. Internal remodeling central 3. Types canal marrow a. Woven b. Lamellar i. Cancellous/Trabecular ii. Cortical/Compact during internal remodeling of bone, osteoclasts invade a section of compact bone and resorb enough bone to C. Joints create large resorption canals (often irregularly shaped borders with the dimensions of a new osteon); into 1. Synovial this newly created tunnel, blood vessels and osteoprogenitor cells enter; osteoblasts begin to deposit new bone 2. Intervertebral along the wall of the tunnel, forming lamellae (Lt. “thin plates”) of new bone; synthesis of new bone continues V. Summary from the periphery to the center of the canal, with concentric layers (rings) of new bone being deposited until only the small central canal of the osteon remains with the neurovascular bundle at the center Labs 6/7 – Cartilage and Bone IUSM – 2016

I. Introduction Slide 13a (464): Developing Bone, H&E II. Learning Objectives III. Keywords IV. Slides A. Cartilage 1. Hyaline 2. Elastic 3. Fibrocartilage woven B. Bone bone 1. General Overview 2. Formation and Growth a. Intramembranous formation b. Endochondral formation c. Appositional growth d. Internal remodeling 3. Types a. Woven b. Lamellar i. Cancellous/Trabecular ii. Cortical/Compact C. Joints new bone, regardless of the process of its formation (e.g., intramembranous or endochondral formation) is 1. Synovial considered immature due to its lack of organization of its bone matrix (it is non-lamellar bone); because of the 2. Intervertebral random arrangement of the osteocytes and the interspersed haphazard collagen fiber arrangement, new bone V. Summary is referred to as woven bone; woven bone will be remodeled into cortical bone and trabecular bone Labs 6/7 – Cartilage and Bone IUSM – 2016

I. Introduction Slide 12 (464): Decalcified Bone, H&E II. Learning Objectives III. Keywords IV. Slides A. Cartilage endosteum 1. Hyaline 2. Elastic 3. Fibrocartilage B. Bone resorption arrangement of 1. General Overview canal 2. Formation and Growth parallel lamellae of bone matrix a. Intramembranous formation b. Endochondral formation c. Appositional growth osteocyte in lacuna d. Internal remodeling 3. Types a. Woven b. Lamellar i. Cancellous/Trabecular ii. Cortical/Compact C. Joints 1. Synovial new woven bone is generally soon remodeled into lamellar bone which is named due to its distinctive 2. Intervertebral lamellated architecture with parallel layers of sheets (lamellae) of bone matrix, as opposed to the haphazard, V. Summary disorganized matrix arrangement of woven bone; both cancellous/trabecular/spongy and cortical/compact bone are types of lamellar bone Labs 6/7 – Cartilage and Bone IUSM – 2016

I. Introduction Slide 104: Bone, H&E II. Learning Objectives III. Keywords IV. Slides A. Cartilage 1. Hyaline periosteum 2. Elastic 3. Fibrocartilage cortical bone B. Bone 1. General Overview marrow 2. Formation and Growth (with lots of adipocytes) a. Intramembranous formation b. Endochondral formation a of c. Appositional growth cancellous bone (Lt. “lattice”) d. Internal remodeling 3. Types a. Woven b. Lamellar i. Cancellous/Trabecular ii. Cortical/Compact C. Joints cancellous/trabecular/spongy bone is the “sponge-like” network of lamellar bone which extends from the 1. Synovial peripheral cortical bone and fills the interior of bones; it consists of a series of interconnected trabeculae 2. Intervertebral (Lt. “beam/timber”) composed of lamellae of bone matrix; the spaces between the trabeculae are continuous V. Summary and filled with marrow; unlike the marrow shown above, most bones of the body are filled with yellow marrow which is primarily adipose tissue Labs 6/7 – Cartilage and Bone IUSM – 2016 Slide 12 (464): Decalcified Bone, H&E I. Introduction II. Learning Objectives III. Keywords IV. Slides cortical bone A. Cartilage marrow 1. Hyaline 2. Elastic 3. Fibrocartilage B. Bone 1. General Overview 2. Formation and Growth a. Intramembranous formation b. Endochondral formation c. Appositional growth d. Internal remodeling 3. Types a. Woven b. Lamellar i. Cancellous/Trabecular ii. Cortical/Compact skeletal muscle periosteum central canal of osteon resorption canal osteocyte C. Joints 1. Synovial cortical/compact bone is the compact, dense layer of bone tissue found at the periphery (cortex) of bones; it is 2. Intervertebral largely composed of osteons (or Haversian systems) – functional units – which consist of concentric sheets (lamellae) of bone matrix surrounding a (or / ), which contains the blood V. Summary central canal osteonal vessels and nerves that supply the osteon; osteon organization is generally only seen in cortical bone, but it may be seen in large trabeculae of spongy bone; the overall architecture is best observed in ground bone Labs 6/7 – Cartilage and Bone IUSM – 2016

I. Introduction Slide 32: Ground Bone II. Learning Objectives III. Keywords IV. Slides A. Cartilage 1. Hyaline 2. Elastic 3. Fibrocartilage B. Bone 1. General Overview 2. Formation and Growth a. Intramembranous formation b. Endochondral formation c. Appositional growth d. Internal remodeling 3. Types a. Woven look here to see look here to see b. Lamellar osteons in osteons in i. Cancellous/Trabecular cross-section longitudinal (transverse) ii. Cortical/Compact section C. Joints 1. Synovial unlike the previous slides of bone which were chemically decalcified in order to permit them to be sectioned normally like other tissues, ground bone is not fixed but simply allowed to dry and then ground into thin 2. Intervertebral sections; while most of the cells and tissue are lost, this method keeps the calcified bone matrix intact and V. Summary permits better appreciation of the bone architecture, especially of the osteons of compact bone Labs 6/7 – Cartilage and Bone IUSM – 2016

I. Introduction Slide 32: Ground Bone II. Learning Objectives III. Keywords Transverse Section IV. Slides A. Cartilage 1. Hyaline 2. Elastic central 3. Fibrocartilage canals B. Bone 1. General Overview 2. Formation and Growth a. Intramembranous formation b. Endochondral formation c. Appositional growth d. Internal remodeling 3. Types outline of a. Woven 2 osteons b. Lamellar i. Cancellous/Trabecular ii. Cortical/Compact C. Joints 1. Synovial 2. Intervertebral V. Summary Labs 6/7 – Cartilage and Bone IUSM – 2016 Slide 32: Ground Bone I. Introduction II. Learning Objectives Transverse Section III. Keywords IV. Slides interstitial A. Cartilage lamellae 1. Hyaline 2. Elastic 3. Fibrocartilage B. Bone lamella (sheet) 1. General Overview of bone matrix central 2. Formation and Growth canal a. Intramembranous formation b. Endochondral formation c. Appositional growth canaliculi d. Internal remodeling (faint lines) 3. Types a. Woven b. Lamellar i. Cancellous/Trabecular ii. Cortical/Compact C. Joints lacunae (spaces) 1. Synovial within each osteon, the concentric lamellae of bone matrix are clearly visible; lacunae, which in living bone 2. Intervertebral contain osteocytes, occur between the lamellae; from the lacunae, canaliculi (Lt. “small channels”) radiate V. Summary through the lamellae connecting the osteocytes together and to the central canal (with neurovascular bundle); interstitial lamellae are remnants of osteons that have been partially resorbed during bone remodeling Labs 6/7 – Cartilage and Bone IUSM – 2016 Slide 32: Ground Bone I. Introduction II. Learning Objectives III. Keywords Transverse Section IV. Slides A. Cartilage 1. Hyaline 2. Elastic 3. Fibrocartilage B. Bone 1. General Overview perforating (Volkmann’s) 2. Formation and Growth canals a. Intramembranous formation b. Endochondral formation c. Appositional growth d. Internal remodeling 3. Types a. Woven b. Lamellar i. Cancellous/Trabecular ii. Cortical/Compact C. Joints 1. Synovial perforating (Volkmann’s) canals generally run perpendicular to osteons and provide links between 2. Intervertebral individual central (haversian) canals; they transmit neurovascular bundles between the periosteum and the bone V. Summary Labs 6/7 – Cartilage and Bone IUSM – 2016

I. Introduction Slide 15a (464): Fetal Joint II. Learning Objectives III. Keywords IV. Slides A. Cartilage 1. Hyaline 2. Elastic 3. Fibrocartilage B. Bone synovium (synovial membrane) lines 1. General Overview the interior of the joint capsule and 2. Formation and Growth secretes lubricating fluid into cavity a. Intramembranous formation articular cartilage is similar to hyaline b. Endochondral formation cartilage but lacks a perichondrium c. Appositional growth joint cavity d. Internal remodeling 3. Types a. Woven skeletal muscle b. Lamellar i. Cancellous/Trabecular ii. Cortical/Compact periosteum C. Joints look here to see and 1. Synovial Sharpey’s fibers attachment of muscle to the bone 2. Intervertebral (still cartilage this early in development) V. Summary Labs 6/7 – Cartilage and Bone IUSM – 2016

I. Introduction Slide 14a (464): , H&E II. Learning Objectives III. Keywords IV. Slides A. Cartilage (bone of vertebral column) 1. Hyaline 2. Elastic 3. Fibrocartilage B. Bone intervertebral disc 1. General Overview with concentric rings 2. Formation and Growth of fibrocartilage a. Intramembranous formation b. Endochondral formation c. Appositional growth thin layer of d. Internal remodeling hyaline cartilage 3. Types a. Woven vertebra b. Lamellar (bone of vertebral column) i. Cancellous/Trabecular ii. Cortical/Compact C. Joints 1. Synovial 2. Intervertebral V. Summary Labs 6/7 – Cartilage and Bone IUSM – 2016

I. Introduction Slide 23 (NW): Intervertebral Disc II. Learning Objectives III. Keywords IV. Slides A. Cartilage 1. Hyaline 2. Elastic annulus fibrosus 3. Fibrocartilage (Lt. “fiber ring”) B. Bone concentric rings of 1. General Overview fibrocartilage 2. Formation and Growth a. Intramembranous formation b. Endochondral formation nucleus pulposus c. Appositional growth (Lt. “fleshy core”) d. Internal remodeling 3. Types gel-like, shock- absorbing tissue at a. Woven center of disc b. Lamellar i. Cancellous/Trabecular ii. Cortical/Compact C. Joints 1. Synovial 2. Intervertebral this large area of discoloration is V. Summary an artifact of slide preparation Labs 6/7 – Cartilage and Bone IUSM – 2016 Common Confusion:

I. Introduction Hyaline vs. Elastic Cartilage II. Learning Objectives III. Keywords Hyaline cartilage: most common form of cartilage; located in IV. Slides the articular surfaces of movable joints, in the walls of larger A. Cartilage respiratory passages, in the ventral ends of ribs, and in the 1. Hyaline epiphyseal plates of long bones 2. Elastic Look for: (1) homogenous, slightly basophilic matrix; (2) 3. Fibrocartilage chondrocytes arranged in small clusters of 2-4 cells B. Bone 1. General Overview 2. Formation and Growth a. Intramembranous formation Hyaline cartilage b. Endochondral formation c. Appositional growth Elastic cartilage: similar to hyaline but with elastic fibers in d. Internal remodeling ECM providing elasticity to the tissue; found in canal of ear, 3. Types Eustachian tube, epiglottis, and laryngeal cartilages a. Woven Look for: (1) presence of elastic fibers in ECM if specialized b. Lamellar stains are used; (2) matrix is more heterogeneous and less i. Cancellous/Trabecular “glassy” in appearance; (3) greater cell density, thus less ECM ii. Cortical/Compact between cells; (4) larger chondrocytes than in hyaline C. Joints 1. Synovial 2. Intervertebral Elastic cartilage V. Summary Labs 6/7 – Cartilage and Bone IUSM – 2016 Common Confusion:

I. Introduction Hyaline vs. Fibrocartilage II. Learning Objectives III. Keywords Hyaline cartilage: most common form of cartilage; located in IV. Slides the articular surfaces of movable joints, in the walls of larger A. Cartilage respiratory passages, in the ventral ends of ribs, and in the 1. Hyaline epiphyseal plates of long bones 2. Elastic Look for: (1) homogenous, slightly basophilic matrix; (2) lack 3. Fibrocartilage of visible collagen fibers in matrix; (3) lacunae often contain B. Bone two or more chondrocytes (isogenous group); (4) lacunae immediately rimmed with basophilic matrix (less collagen, 1. General Overview more GAGs); (5) generally surrounded by perichondrium 2. Formation and Growth (not seen here) a. Intramembranous formation Hyaline cartilage b. Endochondral formation c. Appositional growth Fibrocartilage: found in intervertebral discs, in attachments d. Internal remodeling of certain ligaments, and in the pubic symphysis; it is 3. Types essentially a combination of hyaline cartilage and dense CT a. Woven Look for: (1) collagen fibers in eosinophilic matrix; (2) b. Lamellar usually only individual chondrocytes in lacunae; (3) lacunae i. Cancellous/Trabecular arranged in rows or clusters; (4) lack of perichondrium ii. Cortical/Compact C. Joints 1. Synovial 2. Intervertebral Fibrocartilage V. Summary Labs 6/7 – Cartilage and Bone IUSM – 2016 Common Confusion:

I. Introduction Dense Regular CT vs. Fibrocartilage II. Learning Objectives III. Keywords Dense regular connective tissue: prominent in , IV. Slides ligaments, and surrounding tissues and organs; collagen A. Cartilage bundles and fibroblasts aligned in parallel to axis of functional 1. Hyaline stress

2. Elastic Look for: (1) parallel, closely packed bundles of collagen 3. Fibrocartilage separated by very little ground substance; (2) fibroblasts are B. Bone relatively sparse and have elongated nuclei lying parallel to the fibers; (3) cytoplasm of fibroblasts is rarely revealed in H&E 1. General Overview stains 2. Formation and Growth a. Intramembranous formation Dense regular CT b. Endochondral formation c. Appositional growth Fibrocartilage: found in intervertebral discs, in attachments of d. Internal remodeling certain ligaments, and in the pubic symphysis; essentially a 3. Types combination of hyaline cartilage and dense connective tissue a. Woven Look for: (1) chondrocytes in lacunae; (2) collagen bundles are b. Lamellar fewer, less densely-packed, and interspersed among cartilage i. Cancellous/Trabecular matrix; (3) tissue generally lacks as uniformly parallel an ii. Cortical/Compact organization as seen in dense CT; (4) few fibroblasts are seen; (5) chondrocyte nuclei are more oval/round, with perinuclear C. Joints cytoplasm generally evident, than fibroblast nuclei; (6) 1. Synovial chondrocytes usually appear in linear clusters surrounded by 2. Intervertebral cartilage matrix Fibrocartilage V. Summary Labs 6/7 – Cartilage and Bone IUSM – 2016 Common Confusion:

I. Introduction Cartilage vs. Bone II. Learning Objectives III. Keywords Cartilage: a specialized type of solid connective tissue which, IV. Slides along with bone, is distinguished by its relative rigidity of the A. Cartilage extracellular matrix (ECM); hyaline, the most common type, is pictured here 1. Hyaline 2. Elastic Look for: (1) lack of vasculature, lymphatics, and nerves; (2) 3. Fibrocartilage large proportion of cells to ECM; (3) chondrocytes may occur as B. Bone pairs within a lacuna and tend to be clustered together (isogenous groups) reflecting interstitial growth; (4) 1. General Overview chondrocytes are usually larger and rounder than osteocytes; 2. Formation and Growth (5) matrix is often not uniform and tends to heterogeneously a. Intramembranous formation stain; (6) lack of lamellar architecture Hyaline cartilage b. Endochondral formation c. Appositional growth a specialized type of solid connective tissue which is d. Internal remodeling Bone: characterized by a mineralized ECM that stores calcium and 3. Types phosphate a. Woven b. Lamellar Look for: (1) vasculature; note the central canal (osteon) containing visible erythrocytes; (2) more ECM and fewer cells; i. Cancellous/Trabecular (3) osteocytes are singular and spaced apart; (4) osteocytes ii. Cortical/Compact are smaller and more condensed than chondrocytes; (5) canals C. Joints and lamellar organization may be visible 1. Synovial 2. Intervertebral V. Summary Decalcified bone Labs 6/7 – Cartilage and Bone IUSM – 2016 Common Confusion:

I. Introduction Woven vs. Lamellar Bone II. Learning Objectives III. Keywords Woven bone: immature, newly-synthesized bone; all new bone, IV. Slides regardless of process of formation, is woven bone; it lacks an A. Cartilage organized architecture for the fibers in the ECM 1. Hyaline Look for: (1) lack of lamellar organization of ECM; (2) greater 2. Elastic cell density than mature bone with seemingly random 3. Fibrocartilage arrangement of cells; (3) matrix contains more ground B. Bone substance so more basophilic staining; (4) deposit of matrix and remodeling is not uniform giving overall mottled appearance 1. General Overview 2. Formation and Growth a. Intramembranous formation Woven bone b. Endochondral formation c. Appositional growth mature bone; remodeled from woven bone by d. Internal remodeling Lamellar bone: osteoclasts and osteoblast activity; bone matrix is deposited and 3. Types organized in lamellae (sheets), either in long parallel a. Woven arrangements on in concentric rings as in osteonal architecture; b. Lamellar both cortical/compact bone and trabecular/spongy are lamellar i. Cancellous/Trabecular Look for: (1) less ground substance in matrix so more ii. Cortical/Compact eosinophilic staining; (2) lamellar (sheets) arrangement of C. Joints matrix; (3) in cortical bone, osteons with evident central canals 1. Synovial 2. Intervertebral V. Summary Decalcified lamellar bone Labs 6/7 – Cartilage and Bone IUSM – 2016 Summary

I. Introduction 1. Cartilage is a specialized type of solid connective tissue that, along with bone, is distinguished II. Learning Objectives from other CT by the relative rigidity of its extracellular matrix (ECM); it generally grows by III. Keywords either appositional or interstitial growth; it consists of two major cell types: IV. Slides A. Cartilage a. Chondroblasts are generally located at the periphery of cartilage at the interface with the surrounding dense CT ( ); they secrete new cartilage matrix for 1. Hyaline perichondrium appositional growth of cartilage, eventually becoming encased within the newly- 2. Elastic synthesized matrix. 3. Fibrocartilage b. Chondrocytes are chondroblasts that have become encased in cartilage matrix; they are B. Bone located in spaces in the matrix called lacunae and are responsible for ECM maintenance 1. General Overview and occasionally for interstitial growth of cartilage. 2. Formation and Growth a. Intramembranous formation 2. The three types of cartilage (hyaline, elastic, fibrocartilage) are distinguished by the b. Endochondral formation characteristics of their matrix (e.g., the dominant type of protein fiber). c. Appositional growth d. Internal remodeling 3. Bone, like cartilage, is a specialized type of solid connective tissue; however, it is characterized by a mineralized ECM; newly-formed bone is referred to as due to its interlaced 3. Types woven bone collagen fibers; woven bone is replaced by lamellar bone (mature) with organized sheets of a. Woven bone matrix. b. Lamellar i. Cancellous/Trabecular 4. Lamellar bone is classified as either cortical/compact which is dense and located at the cortex ii. Cortical/Compact of bones, or cancellous/trabecular which is has an intricate meshwork of bone that fills the C. Joints medulla of bones, with the interconnected spaces within the meshwork are filled with marrow. 1. Synovial 2. Intervertebral 5. The functional unit of compact bone is the osteon, consisting of a central canal (containing a V. Summary neurovascular bundle) and concentric rings of bone matrix called lamellae (osteocytes occupy lacunae between adjacent lamellae). Labs 6/7 – Cartilage and Bone IUSM – 2016 Summary (cont.)

I. Introduction 6. Bone formation occurs via one of two processes: in intramembranous ossification new bone II. Learning Objectives forms directly from mesenchyme tissue, while in endochondral ossification bone tissue III. Keywords replaces existing cartilage. IV. Slides A. Cartilage 7. Bone tissue consists of three major cell types: 1. Hyaline a. Osteoblasts derive from osteoprogenitor cells from mesenchyme stem cells; they secrete 2. Elastic type I collagen and bone matrix proteins (osteoid) as well as calcify the matrix to form 3. Fibrocartilage new bone. B. Bone b. Osteocytes are mature osteoblasts which have become encased by osteoid; they are long- 1. General Overview lived cells that maintain the bone matrix and are able to communicate via canaliculi 2. Formation and Growth between lacunae with other osteoctes to respond to mechanical stressors on the bone. a. Intramembranous formation c. Osteoclasts are multinucleated cells formed from the fusion of hematopoietic progenitor b. Endochondral formation cells; they are responsible for bone resorption. c. Appositional growth d. Internal remodeling 3. Types a. Woven b. Lamellar i. Cancellous/Trabecular ii. Cortical/Compact C. Joints 1. Synovial 2. Intervertebral V. Summary Labs 6/7 – Cartilage and Bone Cartilage and Bone Tissue Compare and Contrast IUSM – 2016

I. Introduction Terms Compare and Contrast (Similarities? Distinctive differences?) II. Learning Objectives III. Keywords Cartilage vs. Bone IV. Slides A. Cartilage Hyaline vs. 1. Hyaline Fibrocartilage 2. Elastic 3. Fibrocartilage Chondroblast vs. B. Bone Chondrocyte 1. General Overview

2. Formation and Growth Periosteum vs. a. Intramembranous formation Endosteum b. Endochondral formation c. Appositional growth Appositional vs. d. Internal remodeling Interstitial growth 3. Types a. Woven Cortical vs. Spongy b. Lamellar bone i. Cancellous/Trabecular ii. Cortical/Compact Woven vs. Lamellar C. Joints bone 1. Synovial 2. Intervertebral Intramembranous vs. V. Summary Endochondral oss.