Lecture 2 Anatomy 1 Fall PDF

Dr. Dalia El-wafaey Associate professor of Anatomy & Embryology sinaiuniversity.net 1  Bones Joints Muscles INDEX @Sinaiunieg [email protected] www.s...

Dr. Dalia El-wafaey Associate professor of Anatomy & Embryology sinaiuniversity.net 1  Bones Joints Muscles INDEX @Sinaiunieg [email protected] www.su.edu.eg  Skeletal System (Bones) @Sinaiunieg [email protected] www.su.edu.eg Classification of the skeleton: - The skeleton as a whole is formed from: A. Axial skeleton: formed from: 1- The skull and the mandible. 2-Vertebral column: 33 vertebrae a- 7 cervical. b- 12 thoracic. c- 5 lumbar. d- 5 sacral vertebrae: fused to form the sacrum. e- 3 – 4 coccygeal vertebrae fused with each other to form the coccyx. 3- Thoracic cage a- The sternum. b- 12 pairs of ribs @Sinaiunieg [email protected] www.su.edu.eg B. Appendicular skeleton: the bones of the upper and lower limbs. 1- Lower limb: a- Pelvic girdle: formed from the hip bone. b- Femur: bone of thigh. c- Tibia and fibula: bones of leg. d- Bones of foot: tarsals, metatarsals and the phalanges. 2- Upper limb: a- Shoulder or pectoral girdle: formed from the scapula and the clavicle. b- Humerus: bone of the arm. c- Radius and ulna: bones of forearm. d- Bones of hand: carpus, metacarpus and the phalanges @Sinaiunieg [email protected] www.su.edu.eg Classification of Bones: 1- Long bone: The bone which its length is greater than its breadth is called long bone. It has 2 ends and shaft. They are found in the limbs: a- In lower limb: femur, tibia, and fibula. b-In upper limb: humerus, radius, and ulna Each end is called “Epiphysis” Shaft is called “Diaphysis” Before puberty an “Epiphyseal plate” lies between diaphysis & epiphysis @Sinaiunieg [email protected] www.su.edu.eg 2- Short bones: these are bones that has no length but has definitive shape they are present in the hand (carpal) and in the foot (tarsal). 3- Flat bones: Examples are bones of the vault of the skull (frontal, parietal, and occipital) and the scapula. 4-Irregular bones : e.g. the vertebrae and the bones of the base of the skull. The hip bone is considered as an irregular bone. 5-Pneumatic bones: these bones contain cavities filled with air. They are present in some bones of the skull as the maxilla that contain maxillary air sinus. 6-Sesamoid bone: bones which lie inside muscle tendons for protection and decrease friction. e.g.: patella @Sinaiunieg [email protected] www.su.edu.eg Functions of Skeletal System (bone) SUPPORT: Hard framework gives the body its shape & supports the body. PROTECTION: Surrounds organs such as the brain, spinal cord and internal organs. ATTACHMENT: for muscles & ligaments attachment. MOVEMENT: act as levers at the joints. STORAGE: Minerals as calcium and phosphorus are stored within bone material. BLOOD CELL FORMATION: The bone marrow is responsible for blood cell production. Weight bearing @Sinaiunieg [email protected] www.su.edu.eg Joints @Sinaiunieg [email protected] www.su.edu.eg The Joints Def. :The sites of meeting between two bones or more are called joints. Not all joints permit movements. The joints are classified into three types; According to the type of the material that binds the forming bones A. Fibrous joints: the articular surfaces of the bones are bounded together by fibrous tissue. Very little movement can be allowed. The fibrous joints are subdivided into three types : 1- Sutures: the bones of the skull sutures (serrated borders) and attached to each other by fibrous ligaments (sutural ligaments). 2- Gomphosis (peg and socket): limited to the teeth to fix them in their sockets in alveolar margins of the jaw. 3-Syndesmosis: interosseous ligament and membranes like between ulna & radius. @Sinaiunieg [email protected] www.su.edu.eg @Sinaiunieg [email protected] www.su.edu.eg  Primary cartilaginous joints Secondary cartilaginous joints Cartilage type Hyaline Fibrocarilage Duration Temporary Permanent Movement No movement Little movement Examples Epiphyseal plate of long bone Cartilaginous Joints in midline e.g. intervertebral discs @Sinaiunieg [email protected] www.su.edu.eg @Sinaiunieg [email protected] www.su.edu.eg C. Synovial joints: Characters 1- The articular surfaces are covered by hyaline cartilage. 2- It has a fibrous capsule enclosing a joint cavity. 3- The capsule is lined by synovial membrane. 4- The joint cavity contains a film of serous fluid called synovial fluid secreted by the synovial membrane to lubricate the articular surfaces. 5- The joint is supported by a number of ligaments 6- These joints have a wide range of movements @Sinaiunieg [email protected] www.su.edu.eg Classification of synovial joints: According to degree of movement: 1- Plane joints: the articular surfaces are flat. Slight gliding or sliding movements only can be allowed e.g. intercarpal and intertarsal joints. 2- Angular joints: joints that permit movements and form angles between the articulating bones (flexion and extension) e.g. ankle, knee joints 3- Circumduction: joints that permit successive angular movement e.g. hip and shoulder joints. @Sinaiunieg [email protected] www.su.edu.eg  According to the articular parts: 1- Simple joints: only 2 bones articulated with each other e.g. shoulder and hip joints 2- Compound joints: more than 2 bones articulated with each other e.g.elbow or ankle joints 3- Complex joints: bones articulated with presence of intra-articular structure.e.g knee joint According to the axis of movements: 1- Uniaxial joints: a- Hinge joint: these joints resemble a hinge of a door. It moves along transverse axis. It permits flexion and extension only e.g. elbow joint. b- Pivot joint: These joints move along a longitudinal axis and allow rotation only e.g. superior and inferior radio- ulnar joints @Sinaiunieg [email protected] www.su.edu.eg HINGE JOINT PIVOT JOINT 2- Biaxial joints: A- Ellipsoid: an elliptical convex surface is received into an elliptical concave one. It allows flexion and extension, and adduction and abduction. Rotation in this type is impossible e.g. wrist joint. B- Condyloid joints: two convex articular surfaces articulate with two concave articular surfaces. Movements of flexion and extension and a minimal degree of rotation are allowed e.g. knee joint @Sinaiunieg [email protected] www.su.edu.eg ELLIPSOID JOINT CONDYLOD JOINT C- Saddle shaped: Each of the articular surfaces is concavo-convex. The convexity of one surface is received into the concavity of the other one and vice versa. It resemble a saddle on the back of a horse e.g. carpometacarpal joint of the thumb. 3- Polyaxial (Ball and socket) joints: a ball shaped head of one bone is received into a socket-like concavity of another bone. This type permits flexion and extension, abduction and adduction, medial and lateral rotation and circumduction. The examples of this type are the hip and the shoulder joints. @Sinaiunieg [email protected] www.su.edu.eg SADDLE JOINT BALL & SOCKET JOINT - Bursa These are closed fibrous sacs, lined internally with delicate smooth membranes resembling the synovial membrane. They contain a film of serous fluid. They are present between the tendons and the bone or between the tendons and ligaments and the sites where the skin rubs against the bone adjacent to the joints The function of the bursa is to lubricate the movement and minimize friction. @Sinaiunieg [email protected] www.su.edu.eg THANK YOU For any questions feel free to contact me by mail [email protected] Dr. Dalia El-wafaey Associate professor of Anatomy & Embryology 24