CBIO 2200 1st Edition Lecture 12 Outline of Last Lecture I The Matrix of Osseous Tissue II Bone Marrow III Bone Development IV The Fetal Skeleton at 12 Weeks V Bone Elongation VI Normal Orderly Remodeling vs Disorderly Bone Remodeling VII Mineral Resorption VIII Calcium Homeostasis Outline of Current Lecture I Hormones II Phosphate Homeostasis III Factors Affecting Bone IV Fractures and Their Repairs V Bones of the Skeletal System VI The Skull VII General Functions of the Vertebral Column VIII Vertebrae Abnormalities IX 7 Cervical Vertebrae These notes represent a detailed interpretation of the professor s lecture GradeBuddy is best used as a supplement to your own notes not as a substitute Current Lecture I II III IV Hormones a Calcitriol i Calcitriol behaves as a hormone that raises blood calcium concentration ii Rickets Vitamin D deficiency in children and osteomalacia Vitamin D deficiency in adults b Parathyroid Hormone i Parathyroid hormone PTH secreted by the parathyroid glands ii Secrete parathyroid hormone increase calcium levels in blood 1 Uses same mechanisms as Calcitriol to maintain calcium levels 2 In addition it inhibits osteoblasts from synthesizing collagen a This inhibits bone deposition c Calcitonin i Secreted by C cells clear cells aka parafollicular cells cells between follicles of the thyroid gland ii Lowers blood calcium concentration in two ways 1 Stimulates osteoblast activity increase in bone deposition 2 Inhibits osteoclast activity decreasing bone breakdown Phosphate Homeostasis a Average adult has 500 to 800 g phosphorous b 85 to 90 of phosphate in bones c 3 5 to 4 0 mg dL d Occurs in two principle forms i HPO42 mono hydrogen phosphate ions ii H2PO4 e No disorder associated with phosphate levels Factors Affecting Bone a Numerous hormones vitamins and growth factors affect osseous tissue b Anabolic steroids i Taken by athletes ii Short term affects bone and muscle growth in a good way iii Long term closes epiphyseal plate prematurely premature transition from cartilage to bone causes shorter stature enlarged heart often heart attack gynecomastia increase in breast mass testicular atrophy Fractures and Their Repairs a Stress fracture caused by some type of trauma b Pathological fracture break that occurs because of some disease c Fractures classified by structural characteristics i What is the direction of fracture line ii Is there a break in skin iii Are there multiple pieces of bone d Orthopedics treatment of skeleton in normality e Types of fractures i Non displaced bones are not moved because of fracture ii Displaced bones shift because of break likely to have a break in skin iii Comminuted multiple pieces of bone resulted from the break iv Greenstick the bone bends but doesn t break v Buckle fracture it buckles in a spot because of some kind of pressure on weakened bone f How fracture s heal heals in 8 12 weeks i Hematoma formation blood clotting and bone begins to set ii Soft callus formation makes cartilage first iii Hard callus formation osteoblasts lay down bone iv Bone remodeling bone tries to remodel to original form shape sometimes a bump is left g Treating fractures i Closed reduction put cast on did not have to open up skin ii Open reduction surgery necessary reset bone pins and screws iii Cast immobilizes bone as hematoma sets up iv Traction body casts usually used on children only in severe occasions immobilizes the person Chapter 8 The Skeletal System V VI Bones of the Skeletal System a Articulated bones all bones of skeleton attached by pins to study b Disarticulated bones a single bone separate from skeleton c Number of bones i 206 in typical adult skeleton sometimes a few more or less 1 Sesamoid bones patella bone that develops in a tendon 2 Sutural wormian bones bone that develops in a suture ii 270 at birth d Surface markings i Ridges spines bumps The skull a The most complex part of the skeleton b 22 bones joined together by sutures c 8 cranial bones surround cranial cavity which encloses the brain i Make up cranium protects brain ii Touch the brain d 14 facial bones support teeth facial and jaw muscles e Other cavities e g f Paranasal sinuses frontal sphenoid ethmoid and maxillary g Foramina opening in skull blood vessels nerves pass through h Cranial Bones i Cranium braincase protects brain and associated sense organs VII VIII 1 Calvaria skullcap and cranial base ii Foramen magnum spinal fluid passes through iii Base is divided into three basins that comprise the cranial floor 1 Anterior cranial fossa frontal lobe 2 Middle cranial fossa temporal lobe 3 Posterior cranial fossa cerebellum iv 8 bones 1 frontal 2 parietal 2 temporal 1 occipital 1 sphenoid 1 ethmoid i Facial Bones i 14 bones 2 maxillae bones cleft palate if they don t come together 2 palatine bones 2 zygomatic bones 2 lacrimal bones 2 nasal bones 2 inferior nasal conchae 1 vomer 1 mandible starts out as two separate bones j Bones associated with the skull i Auditory ossicles in ear 1 Malleus incus and stapes ii Hyoid bone does not articulate with any other bone sits on top of cartilage General Functions of the Vertebral Column a Functions b 33 vertebrae with intervertebral discs of fibrocartilage c Fiver vertebral groups i 7 cervical ii 12 thoracic iii 5 lumbar iv 5 fused sacral v 4 fused coccygeal d Primary curvatures thoracic and pelvic curvatures one continuous C shaped curve at birth e Secondary curvatures cervical and lumbar f Four normal curvatures S shaped supports holding head upright i Cervical ii Thoracic iii Lumbar iv Pelvic Vetebrae abnormalities a Scoliosis abnormal lateral curvature of the spine i Usually present in thoracic region ii Usually a congenital defect either vertebrae are fused together fused on one side one vertebrae doesn t develop fully b Kyphosis hunchback Widow s hump i Usually from osteoporosis also osteomalcia or spinal tuberculosis c Lordosis swayback exaggerated lumbar curvature IX i Often associated with pregnancy obesity d Typical vertebra i Spinous process ii Transverse processes iii Vertebral body iv Vertebral foramen contains spinal cord v Pedicles vi Facets vii Vertebral arch e Intervertebral disc i Made up of fibrocartilahge ii Outer part is made of anulus fibrosis iii Middle of disc is called nucleus pulposus iv Ruptured disc break in anulus fibrosis and some of the nucleus pulposis comes out v Slipped disc disc slips out of place if it slips back it will cause severe pain from hitting nerve or spinal cord vi Spina Bifida 1