Labs 6/7 – Cartilage and Bone 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. Joints 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 extracellular matrix (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 bones 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 ossification 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 osteoclast and osteoblast 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 chondroblast 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 osteoblasts, osteocytes, and osteoclasts. 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 osteon 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 periosteum 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 joint, 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 bone Marrow 2. Elastic Cartilage Osteoblast 3. Fibrocartilage Central (Haversian) canal Osteoclasts Chondroblasts Osteocyte B. Bone Chondrocytes Osteoid 1. General Overview Compact bone Osteon 2. Formation and Growth Elastic cartilage Perforating (Volkmann’s) canal a. Intramembranous formation Endochondral ossification Perichondrium b. Endochondral formation Endosteum Periosteum c. Appositional growth Fibrocartilage Synovial joint d. Internal remodeling Growth plate Synovium 3. Types Haversian system Trabeculae a. Woven Howship’s lacunae Woven bone b. Lamellar Hyaline cartilage 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 chondrocyte 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 type I collagen, 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 lacuna 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