Presentation on theme: "Skeletal System Fidya, drg, M.Si. Part of Skeletal System Skeleton Cartilages Ligaments Joint Consist of : Birth skeletal 270 Adult skeletal 207/206 Why."— Presentation transcript:
Skeletal System Fidya, drg, M.Si
Part of Skeletal System Skeleton Cartilages Ligaments Joint Consist of : Birth skeletal 270 Adult skeletal 207/206 Why different?
Function of Skeletal Support Storage of minerals Blood cell production Protection Body movement
FUNCTIONS OF THE SKELETON Supports the body. –The bones of the lower limbs support the entire body when we are standing, and the pelvic girdle supports the the abdominal cavity Protects soft body part –The bones of the skull protect the brain; The rib cage protects the heart and lungs. Produces blood cells –All bones in the fetus have red bone marrow that produces blood cells. In the adult, only certain bones produce blood cells.
Stores minerals and fat –All bones have a matrix that contains calcium phosphate, a source of calcium ions and phosphate ions in the blood. Fat is stored in yellow bone marrow Along with the muscles, permits flexible body movement –While articulations ( joints ) occur between all the bones, we associate body movement in particular with the bones of the limbs
Skeletal System Divide into 2 division: Axial skeleton Appendicular skeleton
Mandible Forms the lower jaw Largest, strongest bone of the face It has a body and two upwardly projecting sections called rami Houses lower dentition
Hyoid Bones The hyoid bone above the larynx below the mandible Supports the tongue Assists in swallowing
Os Hyoid Unique part of the skeleton not attach directly to any other bone. Located: the neck region, below the mandible. Suspended from the styloid process of the temporal bone by the stylohyoid muscles and ligaments. Has a body, two lesser cornua extending anteriorly, and two greater cornua, which project posteriorly to the stylohyoid ligaments. Supports the tongue and provides attachment for some of its muscles. It may be palpated by placing a thumb and a finger on either side of the upper neck under the lateral portions of the mandible and firmly squeezing medially.
In case: Fracture Hyoid This bone is carefully examined in an autopsy when strangulation is suspected, because it is frequently fractured during strangulation. However, this is not necessarily the case in children and adolescents, where the hyoid bone is still flexible as ossification is yet to be completed
Auditory ossicle Three small paired bones, called auditory ossicles Located within the middle- ear cavities in the petrous part of the temporal bones. From outer to inner, the malleus (“hammer”), incus (“anvil”), and stapes (“stirrup”). Their movements transmit sound impulses through the middle-ear
Vertebral Column Composed of 33 individual vertebrae, some of which are fused. Consist of 7 cervical, 12 thoracic, 5 lumbar, 4 to 5 fused sacral, and 3 or 5 fused coccygeal Adult vertebral column composed of a total of 26 movable parts. Vertebrae are separated by fibrocartilaginous intervertebral discs. Secured to each other by interlocking processes and binding ligaments. Between the vertebrae are openings called intervertebral foramina that allow passage of spinal nerves.
General structure of vertebrae Common pattern –Body or centrum –Vertebral arch lamina pedicle –Vertebral foramen –Spinous process Muscles attach –Transverse process Muscles attach
General structure of vertebrae Interlocking pattern –Superior and inferior processes interlock –The inferior from above and the superior from the vertebrae below form a movable joint –The movement contributes to spinal rotation Superior Articular Process
Regional Characteristic: Cervical Body is oval, but wide side to side C3 - C7 Spinous process is short and bifid (split) except in C7 Vertebral foramen is triangular Transverse processes contain foramina for blood vessels leading to brain
Cervical Vertebrae C1 Lateral masses articulates with the occipital condyles of the skull
Cervical Vertebrae C1 Inferior articular surface articulates with C2 below Body of the Vertebrae is missing
Cervical Vertebrae C2 The axis has the odontoid process or dens is its unique feature The dens is the missing body of the atlas which fuses with the atlas during embryonic development
Regional Characteristic: Thoracic Body is larger than cervical; heart shaped Spinous process is long and sharp Vertebral foramen is circular Transverse processes project posteriorly and bear facets for ribs
Regional Characteristic: Lumbar Body is massive and kidney shaped Spinous processes are short and blunt Vertebral foramen is triangular Transverse processes are perpendicular to spinous process but has no special features
Regional Characteristic: Lumbar Spinous process projects posteriorly Superior facets directed medially Inferior facets directed laterally Flexion/extension, some lateral flexion, rotation prevented
Sacral Ala are fused remnants of transverse processes that articulate with hip bones to form the sacro iliac joints of the pelvis Sacral promontory –Center of gravity is 1 cm posterior of this point Transverse line are sites of vertebral fusion Sacral foramina transmit blood vessels and nerves Sacralpromontory Ala
Sacral On the posterior aspect median sacral crest are fused spinous processes The vertebral canal continues inside the sacrum as the sacral canal Sacral hiatus is at the inferior end of the sacral canal Superior articular surface form a joint with the spinal column
Coccyx Coccyx articulates with sacrum
Sternum Located on the anterior midline of the thorax Consists of three fused bones; manubrium, body, and xiphoid process Manibrium articulates with clavicle & 2 ribs Body with ribs 2 - 7 Xiphoid attachment site for abdominal muscle
Ribs are bowed flat bones Long shaft Tear drop shaped with a costal groove on inner surface Head of rib has 2 facets to articulate with its vertebrae as well as the one above
Ribs Tubercle of rib articulates with transverse process Ligaments secure rib to transverse process Note how the transverse processes of thoracic vertebrae are angled posteriorly
Rib Cage The cone-shaped, flexible rib cage, consists of the thoracic vertebrae, 12 paired ribs, costal cartilages, and the sternum. Encloses and protects the thoracic viscera Directly involved in the mechanics of breathing.
Pectoral Gridle Two scapulae and two clavicles having only an anterior attachment to the axial skeleton sternoclavicular joint at the sternum. Lacking a posterior attachment to the axial skeleton, the pectoral girdle has a wide range of movement. Function: - To provide attachment areas for the numerous muscles that move the shoulder and elbow joints.
Claviculae Lies almost horizontally on each side of the neck, extending from the sternum to the acromion of the scapula
The humerus is the longest and largest bone of the upper limb. It extends from the scapula to the elbow joint and has a body and two ends
The bones of forearm The radius The radius is the lateral bone of the two in the forearm. It has a shaft and two ends. The proximal end A head, neck and tuberosity; head is disc-shaped and its upper surface is a shallow cup—articular fovea for articulation with the capitulum of the humerus. Its articular circumference articulates with radial notch of the ulna. Shaft of radius : interosseous border Distal end Ulnar notch, styloid process, carpal articular surface
The bones of hand Three parts: the carpal bones, the metacarpal bones and phalanges The carpal bones There are eight short bones, arranged in two rows of four Proximal row from lateral to medial include: Distal row from lateral to medial include:
Pelvic Gridle Formed by two ossa coxae. together with sacrum and coccyx pelvis United anteriorly at the symphysis pubis Attached posteriorly to the sacrum of the vertebral column. Function: - support the weight of the body from the vertebral column (with assosiated ligament) - supports and protects the lower viscera, (urinary bladder, reproductive organs, developing fetus)
Lower Extermitas The lower limb which is similar to the upper, is connected to the trunk by a girdle, the pelvix girdle, the free lower limb is divided into three segements, the thigh, the leg and the foot. Femoralis Genu Crus : - Tibia - Fibula Pes