SKELETAL SYSTEM.pdf

SKELETAL SYSTEM 4. IRREGULAR BONES - support spinal bones against compression All the bones, joints forces...

SKELETAL SYSTEM 4. IRREGULAR BONES - support spinal bones against compression All the bones, joints forces Made up of cells (osteocytes), protein fibers, - vertebrae, facial bones or hip bones) minerals 5. SESAMOID BONES Adult: 206 bones - small bones embedded within certain tendons, New Born: 305 bones; did not ossify yet fibrous cords that connect muscle to bones. SKELETON - patella, pisiform carpal 6. ACCESSORY BONES “dried-up body” - found in foot Osteocytes – numerous in cell Occur when developing bones do not fuse - characteristics of adult bone completely MATRIX SUTURAL BONES - accessory bones that - Intercellular substance of bones occurs as a small bone cluster between - Organic content of bone (collagen, protein) the joints of flat bones of the skull - flexibility of bone - Frontal, Parietal bone CALCIUM PHOSPHATE CRYSTALS - hardness and strength of bone BONE TISSUE FUNCTIONS: - 20 % of water - Rigid – Calcium Phosphate + Calcium Carbonate 1. MECHANICAL FUNCTIONS = hydroxyapatite crystals a) Support - substance that ionizes and releases the - supporting framework required amounts of calcium or - shape, alignment, positioning of body phosphate parts - Calcium – gives the bones the required b) Protection strength for protective and __________ - hard bony boxes function - serves to protect the delicate structure they enclose (e.g. Ribs) GROSS ANATOMY c) Movement ▪ Has tubular shape - bone in the joints (lever) 1. Diaphysis - as muscle contracts it shortens, - body of long bone produces movements at the joints. -hallow cylinder with walls of compact bone 2. PHYSIOLOGICAL FUNCTIONS tissues. a) Mineral Storage 2. Medullary Cavity - bone serves as major reservoir for - contains yellow marrow which is mostly fat in calcium, phosphorous and other adult minerals. Endosteum – lines the medullary cavity - homeostasis of the blood of the compact bone concentration is essential for survival. Periosteum – covers the outer surface of b) Hematopoiesis the bone except joints. - blood cell formation is carried on by the - contains nerves, lymphatic vessels, red bone marrow/ myeloid tissue capillaries that provides nutrients to the (located at epiphysis) bone. - Flat bones of skull, pelvis, sternum 3. Epiphysis Myeloid – epiphysis (location) - distal and proximal ends of the bones CLASSIFICATIONS - wider than the shaft of long bones - long bones of toes and finger has only one 1. LONG BONES epiphysis – proximal - Length is greater than its width 4. Metaphysis - Humerus, ulna, radius, femur, finger bones) - between diaphysis and epiphysis 2. SHORT BONES - where diaphysis joins epiphysis - equal in length, width and thickness but they DIVISION are shaped irregularly. - carpals, tarsals 1. AXIAL SKELETON 3. FLAT BONES - Longitudinal axis of body - thin, curve, more often than they are flat. - skeletal, vertebral column, thoracic cage - ribs, sternum, skull bones, scapula - 80 bones  2. Palatine Bones (2) 2. APPENDICULAR SKELETON - form the posterior part of the hard palate, walls - Upper and lower extremities, pectoral pelvic of nasal cavity, floor of orbit girdle. 3. Zygomatic Bones (2) - lie below lateral to the eye sockets AXIAL SKELETON 4. Lacrimal Bone SKULL (29 bones) - medial - rests on the superior end of the vertebral - thin bone forming the orbital column - each has a groove that serves a passageway for - serves as supporting framework tears -protects brains, eyes, nasal passages, inner 5. Nasal Bone ear - small triangular bone forming the bridge of nose - articulated to the frontal bone Paranasal Sinuses 6. Vomer Bone (1) - Small air-filled cavities lined with mucous - single thin bone membrane connected to nasal cavity. - medial line to the frontal bone - Contains foramina/foramen; where vessels 7. Inferior Nasal Conchae (2) passed - thin curved bones projecting from lateral walk of nasal cavity. DIVISION OF SKULL 8. Mandible (1) 1. Cranial Skull (Cranium) - largest and strongest bone of face - supports, protect brains, its surrounding - only movable bone in the face membrane (meninges) and cerebrospinal fluid. - forms condyloid joints 2. Facial Skull - forms framework of nasal and oral cavity. ▪ SUTURES AND FONTANELS ▪ CRANIUM Sutures – considered as joint but immovable 1. Frontal Bone (1) Joint – junction of 2 bones - forms forehead, above eyes -at birth it is divided into 2 parts then eventually MAJOR SUTURES: fuses - marked: supra orbital foramen 1. Coronal Suture Foramen – opening, hole, passage in a bone - between frontal and parietal 2. Parietal Bone (2) 2. Lambdoid / Lambdoidal Suture - located at each side of the skull - between parietal and occipital 3. Occipital Bone (1) 3. Sagittal Suture - forms the floor and back of skull - between right and left parietal bone -most posterior bone of cranium 4. Squamous Suture - marked: foramen magnum (at the base) - between temporal and parietal 4. Temporal Bone (2) FUNCTIONS OF SUTURES: - form part of the sides of the cranium which joins the parietal bone a) Maintain the patency from infancy to early 5. Sphenoid Bone (1) childhood/adulthood - wedging between several other bones in the b) Skull continues to grow to accommodate the anterior portion of cranium developing brain and demands for expansion. - shape: similar to bat FONTANELS: 6. Ethmoid Bone (1) - forms the root of nasal cavity and parts of medial - Large membranous areas between incomplete walls of the orbit. ossified bones 7. Sutural bones - Soft spots - “wormian bones” - Allows skull to expand as the child grow - at the age of 2, fontanels ossify and becomes the ▪ BONES OF THE FACE covering Glabella – smooth prominence in the 1. Anterior Fontanel eyebrow 2. Posterior Fontanel 1. Maxillae (2) 3. Sphenoid Fontanel - fuse to form the upper jaw located anterior to 4. Mastoid Fontanel hard palate. - carried upper teeth in alveolar margin  PURPOSE: 3. Lumbar Curve - convex, backward, primary curve, present in a) Permits the compression of infant skull fetus b) Permits the growth of the brain FUNCTIONS: HYOID BONE (1) - Provides spring and resiliency and necessary to - “U” shaped, located inferior to the root of the cushion in walking, maintains center of gravity in tongue, superior to the larynx the body. - Supports the tongue, provide attachment sites to the muscle in speaking and swallowing ABNORMAL CURVATURES OSSICLE of the EAR 1. Scoliosis - lateral curvature of the spine - Small bony structure of ear 2. Kyphosis - Middle ear (within the temporal bone) - exaggerated outward curvature of thoracic - 3 auditory/ ossicle region resulting in rounded upper back. - Transmits sound waves form the tympanic 3. Lordosis membrane (ear drum) or ear drum to inner ear. - abnormally increase inward curvature of the 1. Malleus (Hammer) (2) lower region of spine resulting in a concave back. - outermost part and largest bone of ear - attached to the tympanic membrane SPINAL COLUMUN 2. Incus (Anvil) (2) 1. Cervical Vertebrae - middle bone - 7 small, neck vertebrae 3. Stapes (Stirrup) (2) -support, enable to move up, down and sideways - smallest bone in the body - Transverse Foramina- pair of opening VERTEBRAL COLUMN/ SPINE/ SPINAL COLUMN -found only in this vertebra - Atlas- first cervical vertebra - Extends from the base of skull through the entire -support the head length of trunk - Axis- second vertebra - 26 separate bones (vertebrae), joined by a 2. Thoracic Vertebrae cartilaginous___________________ - chest INTERVERTEBRAL DISC - 12 vertebrae Cervical (neck)- 7 - increase in size as they progress down Thoracic (chest)- 12 - first 4, similar to cervical vertebrae, last 4 had a Lumbar- 5 common feature with lumbar vertebrae Sacral- 5, fuse into 1 3. Lumbar Coccygeal- 3-5, fuse into 1 - back, 5 vertebrae Child- 32 separate bones - largest and strongest vertebrae - carries half part of the body FUNCTIONS: - situated between thorax and pelvis 4. Sacrum a) Forms a strong but flexible support for the neck - provides stability and strength to pelvis and trunk - 5 vertebral bodies fused into 1 b) Protects the spinal cord and spinal nerve roots Coccyx – human tailbone c) Provides support on the body - irregular shape d) Gives an erect posture INTERVERTEBRAL DISC THORAX (CHEST) - includes ribs, sternum, thoracic vertebrae. - Acts as shock absorber during movement Costal cartilage - Allows movement without damaging the - thoracic skeleton vertebrae - formed by intervertebral disc of 12 CURVATURE OF VERTEBRAL COLUMN thoracic vertebrae, by 12 pairs of ribs, 12 costal cartilages and the sternum 1. Cervical Curve - protects the heart, lungs and some abdominal - convex forward, secondary curve, do not organs. appear until after birth. - support bones of pectoral girdle. 2. Thoracic Curve - convex, backward, primary curve, present in THORACIC CAGE fetus - role in breathing STERNUM 2. Ulna and Radius (2) - bones of forearm - protection of the heart, lungs, blood vessels from - anatomical position lateral radius physical damage -palm face backward - produces RBC - distal end and up medial to ulna - attachment to most of the ribs 3. Wrist/ Carpals/ Carpus (8) - protects the lungs, portion of liver - 8 short bones connected each other by - first 7 costal cartilages are attached on both ligament sides, articulates to clavicle - gliding - consist of: 4. Metacarpal (5) a) Manubrium – articulates with clavicle - make up the skeleton of the palm of the hand b) Body – articulates with 2nd and 10th pair 5. Phalanges (14) of rubs - finger bones c) Xiphoid Process – does not articulate - 3 phalanges in each finger with ribs or costal cartilages. -proximal, medial, distal except the thumb RIBS - Curve BONES OF THE PELVIC GIRDLE (Lower Limb Girdle) - 12 pairs, articulate posterior with vertebral 1. Pelvic Girdle (2) column - formed by right and left hipbones (ossa coxae) - Intercostal space 2. Hip Bones - TRUE RIBS - broadest bone in the body - Upper 7 pairs of ribs (1-7) a) Sacrum - FALSE RIBS b) Coccyx - Lower 3 pairs of ribs (8-10) - included because of its - FLOATING RIBS articulation to the structure - 11th and 12th Ossa Coxae - attached only to vertebrae - Ischium, ilium, pubis - TYPICAL RIBS - separated in infants, children, young adults - 3-9 and fuses at the age of 15-17 years old. - each wedge shape, end to the head next to spine 1. Ischium FUNCTIONS: -” sit down bone” - absorbs weight when you sit a) Protects heart, lungs blood vessels - forms the most inferior of the coccyx b) Support shoulder girdles, upper limbs bone c) Attachments for the muscle - serves as the attachment for the posterior thigh muscle APPENDICULAR SKELETON ACCETABULUM - Shoulder girdle, upper and lower limbs, pelvic - deep cup; which is a socket of ball and girdle socket joint with the head of femur. 1) Clavicle (Collar Bone) (2) PARTS: - long bone extends from sternum and scapula a) Ischial Tuberosity - acts as braces to hold the arm and helps - roughened area that receives body prevent dislocation weight when one is sitting. -when broken, it caves in immediately b) Ischial Spine 2) Scapula (2) - superior to the tuberosity important in - located posterior to the thoracic cage pregnant woman - located on the thoracic wall between the ribs 2 - narrows the outer pelvis which and 7 the baby passes through during birth. - triangular bone - triangular eminence/distinction. BONES OF UPPER EXTREMITIES – bones of forearms 2. Ilium - largest and upper portion of the coxa, 1. Humerus (2) flares outward - left and right - forming the prominence of the hips - longest and largest bone of the upper limbs - provides many attachment points for - between shoulder and elbow the trunk and hip muscle.  3. Pubis BONES OF LOWER EXTREMITIES - constitute the anterior portion of coxa 1. Femur (Thigh bone) (2) o Symphysis Pubis - between hip and knee - connects the 2 hip bones at - strongest, heaviest and longest in body the anterior part of the body. - supports body and provides mobility via the OTHERS: hip and knee joints Parts: head, neck, greater trochanter, lesser 1. Greater Sciatic Notch (incisures) trochanter and shaft/body -allows blood vessels and large sciatic 2. Patella (knee cup) (2) nerves (largest nerve) to pass into the - within the quadriceps femoris tendon pelvis into the thighs. - protects the knee 2. Obturator Foramen - largest sesamoid bone in the body - allows blood vessels and nerves into 3. Tibia (shinbone) (2) the anterior part of thigh - Left and right 3. Symphysis Pubis (Pubic Bones) - anterior of the medial side of the leg between - each hip bones fuses anteriorly to form knee and ankle a cartilaginous joint. It unites the ossa - supports body weight coxae anteriorly. - 2nd longest and heaviest in the body PELVIS (bowl shaped) 4. Fibula (2) - long bones, slender bone parallel and lateral to - Formed by sacrum and coccyx posteriorly and the tibia two hip bones anteriorly. 5. Tarsus (Tarsal) (14) FUNCTIONS: - composed of 7 proximally located tarsal bones of the foot a) Provides attachment sites for muscle of the -short bones trunk and lower limbs -works together as a lever b) Transfer and transmits the weight of the body - transmit the trust during walking and running. from the vertebrae - calcaneus- heelbone c) Supports and protects the organ within the - talus- ankle pelvis JOINTS ARTICULATION DIVISION - Place/ point of contact of 2 bones 1. Great Pelvis “False Pelvis” - Place where 2 adjacent bones of cartilage join - expanded portion situated above the pelvic brim CLASSIFICATION OF JOINT 2. Lesser Pelvis “True Pelvis” A. Extent of their function, that is their degree of - Obstetrics Pelvis movement - critical region during child birth 1. Synarthrosis - provides the opening for the baby to - immovable pass - articulation in which the bones are rigidly joined together CHARACTERISTICS MALE FEMALE - Sutures More massive More delicate 2. Amphiarthrosis General Prominent Process not - Slightly movable joint appearance processes prominent - allows limited motion/movement Iliac spine Close together Wide apart - vertebrae, pubic symphysis of pelvis Pelvic inlet Heart shaped Round/ oval 3. Diarthrosis Pelvic outlet Narrower Wider - freely movable joints Obturator - move at any direction Oval Triangular - hips, shoulder, knee Foramen Shallower, B. By their structure Symphysis Pubis Deeper, longer shorter - Based on the presence or absence of Acute (less than Obtuse (greater joint cavity and the kind of supporting Pubic Arch 90° than 90°) tissue that binds the bones together. 1. Fibrous - Synarthrosis - Lacks joint cavity  - Convex surface of the bone fit into the concave surface of another. TYPES: - Movement is in single axis a) Suture - Bending motion - Only in the skull - Elbow, fingers, knee, ankle - Thin layers of connective tissue Distal interphalangeal joints connect the bones Proximal interphalangeal b) Syndesmosis joints - Ligaments that make a firm Metacarpal interphalangeal articulation at the inferior tibio-fibular joints joint 2. Pivot Joints - Little movement - Uniaxial joints which is only able to - Slightly movable joint rotate around a central axis c) Gomphosis - No movement of the bone is on - Fibrous joint made up of a peg and a atlanto____________ socket 3. Condyloid Joints - By fibrous periodental ligament (teeth - Modification of the multiaxial ball and - Synarthrosis socket 2. Cartilaginous Joint - Joint is biaxial because the ligaments - Bones are united by the plate of and muscle around the joint limit the hyaline cartilage of a rotation to 2 axes of movement. fibrocartilaginous disk. - Biaxial movement - Metacarpophalangeal joint TYPES: 4. Gliding Joints a) Synchondrosis (primary cartilaginous - Almost always small and are formed joint) by essentially flat articular surface so - Replaced by bone when long bones that one bone slides on another with a stop growing and becomes synostosis minimal axis of rotation - a sealed joint - Gliding - Permits growth - Ex. Joint between articular processes b) Symphysis (secondary synchondrosis) of adjacent vertebra and the joints - Very slightly movable joint between carpal and tarsal bones. - fibrocartilaginous union of bones 5. Saddle Joint - pubic bone, vertebrae, sacrum, ilium - Articular surfaces of both bones are 3. Synovial Joint shape like saddle - Allows greatest range of movement - Multiaxial because of hyaline articular cartilage - Wide range of movement - Diarthrotic, joint cavity, synovial fluid, - Carpometacarpal joint of the thumb. joint capsule, synovial membrane, 6. Ball and Socket Joint bursae (fluid filled sac in joint) - Composed of globe-like head of one bone that fits into a cuplike cavity of TERMS RELATED TO JOINTS another bone. 1. Axis of Rotation - Shoulder and hip joints are ball and - Any movement about a joint, one- socket joints. member pair of articulating bones move in relation in to the other 2. Uniaxial - Movement of a bone at a joint is limited to rotation about one axis. 3. Biaxial - Two movements can take place about 2 axes of rotation. 4. Multiaxial (triaxial) - 3 independent rotation occur about 3 axis or rotation. TYPES OF JOINTS: 1. Hinge Joints