Lesson+2_Musculoskeletal+system.pptx

Lesson 2 Introduction to musculoskeletal system Human Anatomy and Embryology Prof. Mar Ubero Dentistry Index CONTENT -Skeletal system. -Cartilages. -Ossification. -Bones. -Joints. -Muscles. Includes the bones of the skeleton, the cartilages, and ligaments 1. Skeletal system The skeleton is di...

Lesson 2 Introduction to musculoskeletal system Human Anatomy and Embryology Prof. Mar Ubero Dentistry Index CONTENT -Skeletal system. -Cartilages. -Ossification. -Bones. -Joints. -Muscles. Includes the bones of the skeleton, the cartilages, and ligaments 1. Skeletal system The skeleton is divided into 2 groups: -Axial skeleton: skull (or cranium), vertebral column, ribs, and sternum. -Appendicular skeleton: bones of the upper and lower limbs. Adapted Principles from John Wiley of Anatomy and & sons, 2018. Physiology. Ed. 1. Skeletal system Consist of: 206 Bones + Cartilages + Ligaments Martini FH, Tallitsch RB, Nath JL. Human Anatomy. 8th Edition. Pearson Education SA, 2018 1. Skeletal system Functions: ✓ Support. ✓ Storage of minerals. ✓ Blood-cell production. ✓ Protection. Martini FH, Tallitsch RB, Nath JL. Human Anatomy. 8th Edition. Pearson Education SA, 2018 2. Cartilages Avascular form of connective tissue consisting of extracellular fibres (collagen, elastic and reticular fibres) embedded in a matrix that contains cells localised in small cavities. Is nourished by diffusion and has no blood vessels, lymphatics or nerves - Support soft tissues. - Provide a smooth, gliding surface for bone articulations at joints. - Enable the development and growth of long bones. Hyaline cartilage Fibrocartilage Elastic cartilage Images from: ISBN 13: 9780470501450 - John Wiley & Sons Inc - 2011 2. Cartilages: Hyaline cartilage - Most common. Matrix contains a moderate amount of collagen fibres. Location: Between tips of ribs and sternum, covering bone surfaces at synovial joints, supporting larynx, trachea and bronchi, nasal septum. Function: Stiff but flexible support. Reduces stress between bony surfaces. Martini FH, Tallitsch RB, Nath JL. Human Anatomy. 8th Edition. Pearson Education SA, 2018 2. Cartilages: Elastic cartilage - Matrix contains collagen fibres along with a large number of elastic fibres. Location: Auricle of external ear, epiglottis, auditory canal, cuneiform cartilages of larynx. Function: Provides support, but tolerates distortion without damage. Martini FH, Tallitsch RB, Nath JL. Human Anatomy. 8th Edition. Pearson Education SA, 2018 2. Cartilages: Fibrous cartilage - Matrix contains a limited number of cells and ground substance amidst a substantial amount of collagen fibres. Collagen fibres are extremely dense and the chondrocytes are relatively far apart. Location: Pads within knee joint, between pubic bones of pelvis, intervertebral discs. Function: Resists compression. - Prevents bone-to-bone contact. - Limits relative movement. Martini FH, Tallitsch RB, Nath JL. Human Anatomy. 8th Edition. Pearson Education SA, 2018 3. Ossification ➢ Process of replacing other tissues with bone: • Intramembranous ossification: bone develops from mesenchyme or fibrous connective tissue Clavicle, mandible, and the flat bones of the face and skull. • Endochondral ossification: bone replaces an existing cartilage model Bones that bear weigh such as bones of the limbs and vertebral column. Adapted from John Wiley & Sons, 2018. Principles of Anatomy and Physiology. Ed. Panamericana 2018 (15th Ed.). 6 weeks embryo 4. Bones - Calcified, living, connective tissue. - Forms the majority of the skeleton. Consists of: Intercellular calcified matrix + Collagen fibres + Several types of cells in the matrix (osteocytes, osteoclasts and osteoblasts) - Martini FH, Tallitsch RB, Nath JL. Human Anatomy. 8th Edition. Pearson Education SA, 2018 4. Bones Bones function as: - Supportive structure of the body. - Protectors of vital organs. - Reservoirs of calcium and phosphorus. - Levers on which muscles act to produce movement. - Containers for blood-producing cells. Elsevier 2012. Gray´s Basic Anatomy. 12th Ed. ISBN 978-1-455 71078-2 4. Bones: Types of bone Compact bone Dense bone that forms the outer shell of all bones and surrounds spongy bone. Functional unit: Osteon. Within an osteon the osteocytes in compact bone are usually organised in groups around a central canal that contains blood vessels. Spongy bone Consists of spicules of bone enclosing cavities containing bloodforming cells (marrow). Spongy bone forms an open framework, and as a result it is much lighter than compact bone. Thus, the presence of spongy bone reduces the weight of the skeleton and makes it easier for muscles to move the bones. Images from: ISBN 13: 9780470501450 - John Wiley & Sons Inc - 2011 4. Bones: Types of bone Both compact and spongy bone are present in typical bones of the skeleton, such as the humerus. Martini FH, Tallitsch RB, Nath JL. Human Anatomy. 8th Edition. Pearson Education SA, 2018 4. Bones The bone has two ends, or epiphyses, separated by a tubular diaphysis, or shaft. The diaphysis is connected to the epiphysis at a narrow zone known as the metaphysis. Martini FH, Tallitsch RB, Nath JL. Human Anatomy. 8th Edition. Pearson Education SA, 2018 • Epiphysis • Diaphysis (shaft) • Metaphysis 4. Bones - Growth in length occurs on both sides of the bone at the epiphysial plates. - Growth in thickness occurs in the periosteum. Growing region While growing, osteoblasts are creating more bone than osteoclasts are removing. As adult, osteocytes are continually removing surrounding and replacing calcium salts. the Bone remodelling involves the simultaneous Martini FH, Tallitsch RB, Nath JL. Human Anatomy. 8th Edition. Pearson Education SA, 2018 process of adding new bone and removing previously formed bone. *For example, bone remodelling occurs following the realignment of teeth by an orthodontist. As the teeth are moved, the shape of the tooth socket changes by the reabsorption of old bone and the deposition of new bone according to the tooth's new position. 5. Joints Joint is the site where two skeletal elements come together or articulate. There are two big groups: A. Synovial joint: elements separated by a cavity. B. Solid joint: components are held together by connective tissue (fibrous connective tissue or fibrocartilage). 5. Joints SOLID JOINT: FIBROUS Restricted mobility (or none). Three subtypes: • SUTURES (skull): adjacent bones linked by a thin layer of connective tissue. • GOMPHOSIS: only between teeth and bone, which are articulated by short collagen tissue fibers. • SYNDESMOSIS: Adjacent bones linked by a ligament. e. g. interosseous membrane, which links radius and ulna. 5. Joints SOLID JOINT: CARTILAGINOUS Two subtypes: • SYNCHONDROSIS: two ossification centres in a developing bone remain separated by a layer of hyaline cartilage. They tend to synostose when growth is complete. • SYMPHYSIS: Presence of an intervening pad or disc of fibrocartilage interposed between the articular (hyaline) cartilage that covers the end of two articulating bones. 5. Joints SYNOVIAL JOINTS - A layer of hyaline cartilage covers the articulating surfaces. - Presence of a joint capsule, consisting of an inner synovial membrane and an outer fibrous membrane. - Presence of additional structures: • Articular discs (fibrocartilage). • Fat pads. • Tendons. 5. Joints SYNOVIAL JOINTS 1.Gliding (planar) joint. 2.Hinge joint. 3.Pivot joint. 4.Ellipsoid joint. 5.Saddle joint. 6.Ball-and-socket joint. Moore K; Dalley A, Agur A. Clinical oriented anatomy. 7th Edition. Lippincott Williams & Wilkins, 2013 5. Joints SYNOVIAL JOINTS Gliding (planar) joint Martini FH, Tallitsch RB, Nath JL. Human Anatomy. 8th Edition. Pearson Education SA, 2018 5. Joints SYNOVIAL JOINTS Pivot joint Martini FH, Tallitsch RB, Nath JL. Human Anatomy. 8th Edition. Pearson Education SA, 2018 5. Joints SYNOVIAL JOINTS Saddle joint Martini FH, Tallitsch RB, Nath JL. Human Anatomy. 8th Edition. Pearson Education SA, 2018 5. Joints SYNOVIAL JOINTS Hinge joint Martini FH, Tallitsch RB, Nath JL. Human Anatomy. 8th Edition. Pearson Education SA, 2018 5. Joints SYNOVIAL JOINTS Ellipsoid joint Martini FH, Tallitsch RB, Nath JL. Human Anatomy. 8th Edition. Pearson Education SA, 2018 5. Joints SYNOVIAL JOINTS Ball-and-socket joint Martini FH, Tallitsch RB, Nath JL. Human Anatomy. 8th Edition. Pearson Education SA, 2018 6. Muscles Functions: ✓ Produce skeletal movement. ✓ Maintain posture and body position. ✓ Support soft tissues. ✓ Protect organs. ✓ Controlling the entering and exiting of material. ✓ Maintain body temperature. TYPES: SKELETAL, CARDIAC AND SMOOTH Martini FH, Tallitsch RB, Nath JL. Human Anatomy. 8th Edition. Pearson Education SA, 2018 6. Muscles: SKELETAL MUSCLE • Large, multinucleate cells with a banded or striated appearance. • Innervated by somatic motor nerves (voluntary control). • Insertion on: o Skeleton. o Skin. o Non-skeletal support. • Moves and stabilised the position of the skeleton, generates heat and protects the internal organs. Tendon (200x) Skeletal muscle (400x) Images from: ISBN 13: 9780470501450 - John Wiley & Sons Inc - 2011 6. Muscles: CARDIAC MUSCLE • Short, branched and striated cells (one nucleus). • Innervated by visceral motor nerves (involuntary control). • Found only in the walls of the heart (myocardium). • Resistant to fatigue. • Circulates blood and maintains blood pressure. Electrically and mechanically connected to work as a unit. Cardiac muscular tissue (500x) Images from: ISBN 13: 9780470501450 - John Wiley & Sons Inc - 2011 6. Muscles: SMOOTH MUSCLE • Small, spindle-shaped, with a central nucleus. • They do not branch and have no striations. • Innervated by visceral motor nerves (involuntary control). Slow and sustained contractions. • Found in the walls of blood vessels and structures associated with the gastrointestinal, respiratory and urogenital systems, as well as in hair Images and from: ISBN 9780470501450 - John Wiley & Sons Inc - 2011 follicles the13:eyeball. Smooth muscular tissue BIBLIOGRAP HY Drake RL, Vogl AW, Mitchell AWM. Gray's Basic Anatomy, 4th Edition. Philadelphia, PA: Elsevier, 2019. Drake RL, Vogl AW, Mitchell AWM, Tibbitts R, Richardson P. Gray ́s Atlas of Anatomy, 3rd Edition. Philadelphia, PA: Elsevier, 2020. Martini FH, Tallitsch RB, Nath JL. Human Anatomy. 8th Edition. Pearson Education SA, 2018. Moore K; Dalley A, Agur A. Clinical oriented anatomy. 7th Edition. Lippincott Williams & Wilkins, 2013. Nielsen M, Miller S. Atlas of Human Anatomy. Chichester, UK: John Wiley & Sons Ltd, 2011. Tortorra, G.J. & Derrickson, B. “Principles of Anatomy and Physiology”. Ed. Panamericana 2018 (15th Ed). Maria del Mar Ubero Martinez [email protected] UCAM Universidad Católica de Murcia © UCAM