The Skeletal System PDF

The Skeletal System Lessons:  1. Anatomy and Physiology  2. Pathophysiology In this transcription you will learn about the anatomy of the skeletal system, which includes the bones, cartilage...

The Skeletal System Lessons:  1. Anatomy and Physiology  2. Pathophysiology In this transcription you will learn about the anatomy of the skeletal system, which includes the bones, cartilage, and ligaments of the body. You will find that bone is dynamic tissue, changing daily, and that what you do can affect the changes. Pre-test This pretest shall aim to test your initial knowledge on The Basics of the Anatomy and Physiology with Pathophysiology. It shall seek to know what is the current knowledge or perception you know regarding on the course Instructions: Answer the following questions based on your own understanding. Choose from the provided choices and please put your answers on the space provided before each number. _______1. What do you use to measure acidity and alkalinity? a. Blood Pressure b. Temperature c. pH scale d. Blood sugar _______2. What molecule contains the usable form of energy for the cell? a. ATP b. ACP c. SGPT d. Nucleus _______3. What is the four major types of organic molecules? a.Zinc, Iron, Vit. C and Vit. E b. Lipids, Carbohydrates, Proteins, Nucleic Acids c. Nucleus, Golgi Complex, RER, Mitochondria _______4. What organelles assemble proteins? a. Lysosomes b. Ribosomes c. Nucleolus d. Rough ER _______5. What is programmed cell death? a. Neoplasia b. Apoptosis c. Necrosis How do you rate yourself?  If you got a perfect score, you have appropriate knowledge of the human body and its processes.  If you got a score of 3-4, it means you have a basic knowledge of the human body.  If you got a score of 0-2, it means that you need to have additional readings in anatomy and physiology with pathophysiology. HUMAN ANATOMY AND PHYSIOLOGY WITH THE SKELETAL SYSTEM PATHOPHYSIOLOGY Lesson 1: Anatomy and Physiology Introduction: The human skeleton is divided into two major divisions: the axial skeleton and the appendicular skeleton. The axial skeleton consists of the bones of the head, neck, and trunk. The appendicular skeleton includes the bones of the arm, legs, and girdles. Bones are technically organs because they contain more than one type of tissue, they’re mostly made of Osseous (bone) tissue they also contain cartilage, muscle, nervous, and epithelial tissues. TWO SKELETAL BONES: AXIAL SKELETON – consist of 80 bones that comprises the upright, central supporting axis of the body: skull, rib cage, and vertebral column. APPENDICULAR SKELETON- consists of 126 bones which makes up the limbs, pelvic, and shoulder area. CLASSIFICATION OF BONES: Long Bones These bones have a very long axis and are longer than they are wide. Examples include the femur of the thigh and the humerus of the arm. Long bones work like levers to move limbs. Short Bones About as broad as they are long, these tend to be shaped like cubes. Examples include the carpal bones of the wrist and the tarsal bones of the ankle. Flat Bones These thin, flat, often curved bones protect organs, such as the bones of the skull, the ribs, and the breastbone (sternum). Others, such as the shoulder blades (scapulae), provide a large surface area for the attachment of muscles. Irregular Bones Often clustered in groups, these bones come in various sizes and shapes. Examples include the vertebrae and facial bones. Sesamoid Bones Are small bones embedded in tendons. The kneecap is an example of a sesamoid bone. HUMAN ANATOMY AND PHYSIOLOGY WITH THE SKELETAL SYSTEM PATHOPHYSIOLOGY AXIAL SKELETON: THE SKULL CRANIUM The cranium is the bony structure housing the brain. It consists of eight cranial bones:  Parietal bones (2 bones): Join together at the top of the head to form the top and sides of the cranial cavity.  Occipital bone (1 bone): Forms the rear of the skull.  Temporal bones (2 bones): Form the sides of the cranium and part of the cranial floor; also contain the structures of the inner and middle ear, including the: External auditory meatus (an opening into the ear) Mastoid process (a prominent lump behind the ear) Zygomatic arch (cheekbone) Styloid process (an attachment point for several neck muscles).  Frontal bone (1 bone): Forms the forehead and the roof of the eye sockets (orbits).  Sphenoid bone (1 bone): Forms a key part of the cranial floor as well as the floor and side walls of the orbits.  Ethmoid bone (1 bone): Contributes to the walls of the orbits, the roof and walls of the nasal cavity, and the nasal septum. FACIAL BONES The 14 bones of the face perform several functions. They support the teeth, provide an attachment point for the muscles used in chewing and for facial expression, form part of the nasal and orbital cavities, and also give each face its unique characteristics.  Maxillae (2 bones): These bones meet to form the upper jaw. The maxillae (singular: maxilla) form the foundation of the face; every other facial bone (except for the mandible) articulates with the maxillae. The maxillae form part of the floor of the orbits, part of the roof of the mouth, and part of the floor and walls of the nose.  Zygomatic bones (2 bones): These bones shape the cheeks and form the outer edge of the orbit.  Mandible (1 bone): This is the largest and strongest bone of the face. It articulates with the temporal bone at the temporomandibular joint (TMJ), making it the only facial bone that can move.  Lacrimal bones (2 bones): These paper-thin bones form part of the side wall of the orbit.  Nasal bones (2 bones): These rectangular bones form the bridge of the nose; the rest of the nose is shaped by cartilage. HUMAN ANATOMY AND PHYSIOLOGY WITH THE SKELETAL SYSTEM PATHOPHYSIOLOGY   Inferior nasal conchae (2 bones): The conchae bones (singular: concha) contribute to the nasal cavity.  Vomer (1 bone): This small bone forms the inferior half of the nasal septum. (The superior half is formed by the perpendicular plate of the ethmoid bone.)  Palatine bones (2 bones): These bones form the posterior portion of the hard palate, part of the wall of the nasal cavity, and part of the floor of the orbit. HYOID BONE A U-shaped bone that sits between the chin and the larynx. The hyoid bone—which is the only bone that doesn’t articulate with any other bone—serves as an attachment point for muscles that control the tongue, mandible, and larynx. HUMAN ANATOMY AND PHYSIOLOGY WITH THE SKELETAL SYSTEM PATHOPHYSIOLOGY AXIAL SKELETON: VERTEBRAL COLUMN CERVICAL VERTEBRAE (C1 to C7) C1 (ATLAS) - Named for the Greek god Atlas who carried the world on his shoulders, the role of the first cervical vertebra is to support the skull. C2 (AXIS) - The C2 vertebra, called the axis, has a projection called the dens or odontoid process. The dens projects into the atlas and allows the head to swivel from side to side (such as when saying “no.”) THORACIC VERTEBRAE (T1 to T12) The thoracic cage consists of the thoracic vertebrae, the sternum, and the ribs. These bones form a cone-shaped cage that surrounds and protects the heart and lungs and provides an attachment point for the pectoral girdle (shoulder) and upper limbs. Expansion and contraction of the thoracic cage causes the pressure changes in the lungs that allow breathing to occur. STERNUM - The sternum has three regions.  Manubrium: This is the broadest portion; the suprasternal notch (at the top of the manubrium between the two clavicles) is easily palpated.  Body: This is the longest portion; it joins the manubrium at the sternal angle (also called the angle of Louis), which is also the location of the second rib.  Xiphoid process: An important landmark for cardiopulmonary resuscitation (CPR), the xiphoid process provides an attachment point for some abdominal muscles. RIBS - Twelve pairs of ribs attach to the vertebral column. Ribs 1 to 7, called true ribs, attach to the sternum by a strip of hyaline cartilage called costal cartilage. Ribs 8, 9, and 10 attach to the cartilage of rib 7; these ribs, as well as ribs 11 and 12, are called false ribs. Ribs 11 and 12, called floating ribs, do not attach to any part of the anterior thoracic cage. [NOTE:] The lower edges of the thoracic cage are called the costal margins. The two costal margins meet at the xiphoid process, forming the costal angle. The angle should be less than 90 degrees. Pregnancy as well as lung diseases, such as emphysema, cause the angle to increase. LUMBAR VERTEBRAE (L1 to L5) – Are larger and heavier than vertebral bodies in other regions. It is kidney-shaped when viewed superiorly and is wider from side to side than from front to back and a little thicker in front than in back with a thin cortial shell which surrounds cancellous bones. The posterior aspect of the vertebral body changes from slightly concave to slightly convex from L1 to L5 with an increasing diameter due to the increased load carried at each body. HUMAN ANATOMY AND PHYSIOLOGY WITH THE SKELETAL SYSTEM PATHOPHYSIOLOGY SACRUM – is located in between the right and left iliac (hip) hones, and forms the back of the pelvis. The sacrum is where the sacral spine connects to the pelvis. The point or spinal level where L5 meets S1 is lumbosacral spine. The low back (lumbar spine) with the sacrum (sacral spine) help form the lumbosacral curve, which is integral to supporting the upper body, weight-bearing, maintaining balance, and functional flexibility. COCCYX – or tailbone, is located below the sacrum. It’s much smaller than the sacrum and plays an important weight-bearing role. The coccyx helps support the weight while sitting and when leaning back, the pressure on the coccyx increases. APPENDICULAR SKELETON: PECTORAL GIRDLE Also called the shoulder girdle, the pectoral girdle supports the arm. The two pectoral girdles— one on each side of the body—consist of a clavicle (collarbone) and a scapula (shoulder blade). CLAVICLE – is a slightly S-shaped bone, the clavicle articulates with the sternum and the scapula and helps support the shoulder. SCAPULA – located on the posterior portion of the thorax; lies over ribs 2 to 7. The lateral portion of this triangle-shaped bone has three main features. The acromion process: This extension of the scapula articulates with the clavicle; it is the only point where the arm and the scapula attach to the rest of the skeleton. HUMAN ANATOMY AND PHYSIOLOGY WITH THE SKELETAL SYSTEM PATHOPHYSIOLOGY  The coracoid process: This finger-like process provides a point of attachment for some of the muscles of the arm. The glenoid cavity: This shallow socket articulates with the head of the humerus (upper arm bone). HUMAN ANATOMY AND PHYSIOLOGY WITH THE SKELETAL SYSTEM PATHOPHYSIOLOGY Table 1.1 Bone markings APPENDICULAR SKELETON: UPPER LIMB The upper limb, or arm, consists of the humerus (upper arm bone), the radius and the ulna (the bones of the lower arm), and the carpals (the bones of the hand). HUMERUS – is the long bone of the upper arm. It contains these features: Head: The enlarged end of this long bone is covered with articular cartilage; it articulates with the glenoid cavity of the scapula. Olecranon fossa: This is a depression on the posterior side of the humerus. Olecranon process: This is the bony point of the elbow; it slides in the olecranon fossa when the arm is extended. (See the pull-out image of the posterior side of the elbow.) RADIUS – is located on the same side as the thumb. The proximal head of the radius is a distinctive disc that rotates on the humerus when the palm is turned forward and back. The radial tuberosity is where the biceps muscle attaches to the bone. ULNA – is the other bone of the lower arm; it is longer than the radius. APPENDICULAR SKELETON: UPPER LIMB The upper limb, or arm, consists of the humerus (upper arm bone), the radius and the ulna (the bones of the lower arm), and the carpals (the bones of the hand). HUMERUS – is the long bone of the upper arm. It contains these features: Head: The enlarged end of this long bone is covered with articular cartilage; it articulates with the glenoid cavity of the scapula. Olecranon fossa: This is a depression on the posterior side of the humerus. Olecranon process: This is the bony point of the elbow; it slides in the olecranon fossa when the arm is extended. (See the pull-out image of the posterior side of the elbow.) RADIUS – is located on the same side as the thumb. The proximal head of the radius is a distinctive disc that rotates on the humerus when the palm is turned forward and back. The radial tuberosity is where the biceps muscle attaches to the bone. ULNA – is the other bone of the lower arm; it is longer than the radius. HUMAN ANATOMY AND PHYSIOLOGY WITH THE SKELETAL SYSTEM PATHOPHYSIOLOGY APPENDICULAR SKELETON: HAND Consists of the wrist, palm, and fingers. PHALANGES – The fingers are formed by bones called phalanges. (The singular form of phalanges is phalanx.) The thumb contains two phalanges; the rest of the fingers contain three. The phalanges are identified by the Roman numerals I through V (beginning with the thumb) and as being proximal, middle, or distal. For example, distal phalanx IV is the tip of the ring finger. METACARPAL – Five metacarpal bones form the palm of the hand. The proximal end is called the base, the shaft is called the body, and the distal end is called the head. The knuckles that appear when you clench your fist are the heads of the metacarpals. CARPAL – Eight carpal bones—arranged in two rows of four bones—form the wrist. These bones allow the wrist to move back and forth as well as side to side. Each bone has an individual name. The carpal bones of the wrist articulate with the five metacarpal (MC) bones. Moving from left to right in two rows, the bones are scaphoid, lunate, triquetrum, pisiform, trapezium, trapezoid, capitate, and hamate. (To help you remember, use the mnemonic "Stop Letting Those People Touch the Cadaver's Hand.") APPENDICULAR SKELETON: PELVIC GIRDLE Each of the two large bones of the hip is called an os coxae; it may also be called a coxal bone or innominate bone. Together they form what’s known as the pelvic girdle: the foundation of the pelvis. The os coxae is not a single bone; rather, it consists of three bones fused together. Ilium: A large, flaring section you can feel under the skin. Ischium: The lower posterior portion. Pubis: The most anterior portion that joins with the other pubis at the symphysis pubis, a disc of cartilage that separates the two pubic bones. PELVIS – The combination of the os coxae and the sacrum is known as the pelvis. The pelvis supports the trunk, provides an attachment point for the legs, and also protects the organs of the pelvis (including the lower colon, reproductive organs, and urinary bladder). The pelvis is divided into a true (lesser) pelvis and a false (greater) pelvis.  The true pelvis extends between what’s known as the pelvic brim.  The pelvic outlet is the lower edge of the true pelvis. The diameter of the pelvic outlet is measured as the distance between the two ischial bones. The pelvic outlet is the passageway through which an infant enters the world; therefore, the distance between the two ischial bones must be wide enough to allow his head to pass.  The false pelvis extends between the outer, flaring edges of the iliac bones. APPENDICULAR SKELETON: LOWER LIMB The bones of the lower limb—which consist of the femur (thigh bone), patella (kneecap), tibia and fibula (bones of the lower leg), and foot—join with the pelvis to give the body a stable base. More importantly, the bones of the lower limb are articulated in such a way as to allow the body to move. FEMUR – The longest and strongest bone in the body, the femur articulates with the acetabulum of the pelvis to form a ball- and-socket joint. PATELLA – Commonly known as the kneecap, the patella is a triangular sesamoid bone embedded in the tendon of the knee. At birth, the patella is composed of cartilage. It ossifies between the ages of three and six years. FIBULA – The long and slender fibula resides alongside the tibia and helps stabilize the ankle. It does not bear any weight. TIBIA – Of the two bones in the lower leg, the tibia is the only one that bears weight. Commonly called the shinbone, the tibia articulates with the femur. FOOT AND ANKLE – The bones of the foot and ankle are arranged similarly to those of the hand. However, because the foot and ankle bear the weight of the body, the size of the bones, as well as how they’re arranged, differs. HUMAN ANATOMY AND PHYSIOLOGY WITH THE SKELETAL SYSTEM PATHOPHYSIOLOGY PHALANGES – The phalanges form the toes. The great toe, called the hallux, contains only two bones: a proximal and distal phalanx. The remaining toes contain a proximal, middle, and distal phalanx. METATARSALS – The metatarsals—which are numbered I through V, beginning medially—form the middle portion of the foot. TARSAL – The tarsal bones comprise the ankle.  The distal row of tarsal bones consists of three cuneiforms and the large cuboid.  The second-largest tarsal bone is the talus. The talus articulates with three bones: the calcaneus on its inferior surface, the tibia on its superior surface, and another tarsal bone (called the navicular) on its anterior surface.  The largest tarsal bone is the calcaneus. This bone, which forms the heel, bears much of the body’s weight. HISTOLOGY OF SKELETAL SYSTEM Histology - study of the microscopic anatomy of cells and tissues Osteology - the study of bones BONE CONNECTIVE TISSUE - a bone is a dynamic tissue - highly calcified, solid, rigid connective tissue Types of bone cell: * Osteoblast * Osteoclasts * OSTEOBLAST - it builds a bone tissue - builds a new bone by forming a soft matrix of protein and carbohydrate molecules with collagen fibers - it allows hard mineral crystals to be deposited in the matrix. Hydroxyapatite - calcium phosphate mineral salt - make the crystal hard - without sufficient hydroxyapatite - where the osteoblast produce collagen fibers Collagen fibers - give the matrix bone flexibility - without collagen fibers, bones become brittle * OSTEOCLASTS - destroy bone tissue - active in breaking down bones for bone remodeling - Which are responsible for bone desorption Types of bone tissue:  Compact bone  Cancellous bone COMPACT BONE - A compact bone is very dense and highly organized. - This type of bone is found in the shafts of lone bones and are surfaces of a flat bone. - Compact bone tissue is arranged in a series of oesteons (Haversian systems) that appears as targets. HUMAN ANATOMY AND PHYSIOLOGY WITH THE SKELETAL SYSTEM PATHOPHYSIOLOGY Osteons (Harvasian System) –the most basic structural unit of the bone. Cylindrical weight baring structures that run parallel to the bones axis. Harvesian canal - contains blood vessels and a nerve. Lamellae - is matrix formed around the canal in concentric layers. Osteocytes - are mature osteoblasts that are found in spaces called lacunae arranged in circles around the central canal. Canaliculi - are the tiny cracks in the matrix allow the osteocytes to reach out to each other and to the central canal for the nutrients. CANCELLOUS BONE - A compact bone is spongy in appearance, characterized by delicate silver and plates of bone with spaces between - This type of bone is found in the end of long bones (epiphysis) and in the middle of flat and irregular bones - Cancellous bone is not as organized as compact bone and it does not have Haversian system - The spaces between this sponge bones are often filled with red bone marrow and blood vessels - Trabeculae arranged in delicate silvers and plates CARTILAGE CONNECTIVE TISSUE Cartilage connective tissue, the cells are called chondrocytes. Chondrocytes produce a matrix of proteoglycans and water. Proteoglycans is basically a protein molecule with a carbohydrate added to it. This type of tissue lacks a blood supply Types of Cartilage:  Hyaline  Elastic  Fibrocartilage  Hyaline Cartilage Connective Tissue - This type of cartilage is found covering the ends of long bones, in the costal cartilage of the ribs, and in the nasal cartilages of the nose  Elastic Cartilage Connective Tissue - This cartilage is found on the pinna of the ear (outer ear flap) and in the epiglottis in the throat.  Fibrocartilage Connective Tissue - This type of cartilage is found in the intervertebral disc. The pubic symphysis, and the meniscus of the knee. Bone Marrow Yellow Bone Marrow – Stores Energy as Fat (can turn into red bone marrow in case of an extreme anemia) Red Bone Marrow – Produces Red Blood Cells also white blood cells and platelets. HUMAN ANATOMY AND PHYSIOLOGY WITH THE SKELETAL SYSTEM PATHOPHYSIOLOGY ANATOMY OF A LONG BONE  Epiphyses - found on clubby ends of a long bone. - Each epiphyses is covered by articular cartilage, which is composed of hyaline cartilage connective tissue Articular cartilage provides a smooth surface for the end a long bone to articulate with another bone. Articular cartilage is firmly attached to the bone. - Cancellous bone is found in the epiphyses. - Red bone marrow fills the spaces between the cancellous bone’s tuberculae.  Diaphysis - Shaft of the long bone - It is composed of compact bone, but it is not a solid bone. Diaphysis is a hollow tube of compact bone filled with the yellow bone marrow in what is called marrow (medullary) cavity. Periosteum a fibrous covering of diaphysis Endosteum source of osteoblasts Nutrient artery enters the bone through a foramen in the diaphysis  RED BONE MARROW is found in the spaces of cancellous bone. This includes flat bones like sternum, irregular bones like the vertebrae, and the epiphyses of long bones. Red bone marrow is composed of stem cells, which produce both red and white blood cells and platelets. HUMAN ANATOMY AND PHYSIOLOGY WITH THE SKELETAL SYSTEM PATHOPHYSIOLOGY  YELLOW BONE MARROW is found in the marrow cavity of mature long bones. The marrow cavity in a developing long bone originally contains red marrow. By the time the bone matures, the marrow has become yellow marrow composed of mostly fatty tissue. JOINTS FIBROUS JOINTS. Fibrous joints have fibrous tissue between the bones. There are three types of joints in this class. Sutures. Immovable. A suture has a fibrous membrane between bones until the suture is completely closed. It can be found between cranial bones of the skull. Gamphoses. Immovable. A gamphoses is formed by fibrous ligaments holding a tooth in its socket. Syndesmoses. Partly movable. A syndesmoses is formed by an interosseous membrane. It can be found between the radius and the ulna and between the tibia and the fibula. CARTILAGINOUS JOINTS. Cartilaginous joints, have cartilage between the bones. Symphyses. Little movements. The pubic symphysis has fibrocartilage between the two pubic bones. This joint becomes more elastic and slightly movable during the birth process. Synchrondroses. Partly movable. Synchrondoses can be found in the long bones of children. A synchondrosis is the cartilage joint between an epiphysis and diaphysis of a long bone. SYNOVIAL JOINTS. Synovial joints have a joint cavity. This joint space is formed by a joint capsule that surrounds and seals the joint space. The joint space is lined by a synovial membrane, which produces a very slippery synovial fluid. This fluid lubricates the joint, reducing the heat of friction as the bones articulate.  Hinge. Very movable in one direction, like a door hinge. C-shaped surface of one bone swings about the rounded surface of another bone. Found on  Ball and socket. Very movable in all direction. Ball of one bone fits into a socket of another. Hip; shoulder  Saddle. All movements possible, but rotation is limited. Concave surface of two bones articulate with one another. Carpometacarpal joint of the thumb.  Gliding. Up-and-down wave of the hand at the wrist. Two opposed flat surfaces of bone glide past one another. Carpal bones  Ellipsoid. All movement but rotation severely limited; side-to-side wave of the hand at the wrist. Reduce ball and socket. Reduce ball and socket HUMAN ANATOMY AND PHYSIOLOGY WITH THE SKELETAL SYSTEM PATHOPHYSIOLOGY   Pivot. Rotation. Ring of bone articulates with a post of bone. Atlas on the odontoid process. The knee is a prime example of synovial joint and the femur, tibia and patella form the knee joint. Five ligaments connect the bones to help support the knee: Medial and lateral collateral ligaments it attach the epicondyles of the femur to the epicondyles of the tibia and fibula. They prevent side-to-side movement at the knee. Anterior and posterior cruciate ligaments attach the femur to the tibia. They cross to form an X between the femur’s condyles, and they are named for their attachment relative to the tibia: the anterior cruciate ligament attaches to the tibia’s anterior, and the posterior cruciate ligament attaches to the tibia’s posterior side. This ligaments prevent the femur from sliding forward or backward relative to the tibia. The patellar ligament, sometimes called the patellar tendon, attaches the patella to the tibia. It qualifies as a tendon and a ligament because it attaches muscle to bone and bone to bone. HUMAN ANATOMY AND PHYSIOLOGY WITH THE SKELETAL SYSTEM PATHOPHYSIOLOGY PHYSIOLOGY OF SKELETAL SYSTEM Mineral deposition- Bone matrix is synthesized by a layer of osteoblasts on the bone surface. Osteoblasts are mononucleate cuboid cells that are responsible for bone formation. They produce the collagen fibers at bone’s hydroxyapatite crystals. They simply allow hydroxyapatite to be deposited. Calcium phosphate is dissolved in body fluids and blood. BONE DEVELOPMENT Intramembranous Ossification Endochondral Ossification 1. This process forms flat bones of 1. This process forms long bones, vertebrae, ribs, sternum, scapula, the skull of the developing fetus. pelvis, and bones of the limbs of the developing fetus. 2. Osteoblasts deposit bones in 2. Osteoblasts deposit bone in cartilage models. membrane. HUMAN ANATOMY AND PHYSIOLOGY WITH THE SKELETAL SYSTEM PATHOPHYSIOLOGY 3. Site of ossification is the center 3. Primary site of ossification is the diaphysis, with deposition toward the of the future bone. epiphyses. Secondary sites are in each epiphysis, depositing toward the diaphysis. 4. Membranes continue to grow as 4. Cartilage of the model continues to grow as bone is being deposited. bone is being deposited. 5. Existing membrane, not yet 5. Existing cartilage between the epiphyses and the diaphysis is called an bone, present at birth is called a epiphyseal plate. fontanelle. 6. Continued membrane growth 6. Epiphyseal plate continues to grow, allowing bones to increase in length. allows bones of the skull to get bigger as the child grows. 7. Development is finished when 7. Development is finished when the epiphyseal plates are completely sutures are completely closed. closed. INTRAMEMBRANOUS OSSIFICATION HUMAN ANATOMY AND PHYSIOLOGY WITH THE SKELETAL SYSTEM PATHOPHYSIOLOGY ENDOCHONDRAL OSSIFICATION BONE GROWTH Endochondral Growth- In this process, the osteoblasts are continuing to deposit bone in the epiphyseal plates. -the chondrocytes continue to expand the plates with cartilage. - race of the two types of cells happens here until it reaches puberty. Appositional Bone Growth -occurs in all types of bone. -In this process, it does no longer makes the bone longer, but it makes it more massive wherein, Osteoblasts of the periosteum deposit more bone on the bone’s shaft and the osteoblasts of the cancellous bone’s trabeculae in the epiphyses deposit more bone along the bone’s lines of stress. BONE REMODELING -A process in which matrix is resorbed on one surface of a bone and deposited on another -bone undergoes remodeling, in which resorption of old or damaged bone takes place on the same surface where osteoblasts lay new bone to replace that which is resorbed. Injury, exercise, and other activities lead to remodeling. NUTRITIONAL REQUIREMENTS OF THE SKELETAL SYSTEM Calcium and Vitamin D -are two of the most important nutrients for a healthy skeletal system. Your bones need calcium to grow properly. If you do not get enough calcium in your diet as a teenager, your bones may become weak and break easily later in life. HORMONAL REGULATION OF BONE DEPOSITION AND REABSORPTION GLAND HORMONE TARGET TISSUE FUNCTION OF HORMONE THYROID Calcitonin 1.Osteoblasts 1. Tells osteoblasts to deposit bone, reducing blood GLAND calcium levels 2.Osteoclasts 2. Inhibits osteoclasts from reabsorbing bone PARATHYROID Parathyroid 1.Osteoclasts 1. Tells osteoclasts to reabsorb bone, increasing blood GLAND Hormone calcium levels. 2. Kidneys 2. Tells kidney to reabsorb calcium, maintaining blood calcium levels 3. Tells small intestine to absorb calcium, increasing blood calcium levels (Vitamin D is required for this work) OVARIES Estrogen Osteoblasts Tells osteoblasts to work faster; serves as a lock on bone by inhibiting osteoclasts TESTES Testosterone Osteoblasts Tells osteoblasts to work faster; serves as a lock on bone by inhibiting osteoclasts (Testosterone has less of an effect than does estrogen.) HUMAN ANATOMY AND PHYSIOLOGY WITH THE SKELETAL SYSTEM PATHOPHYSIOLOGY FUNCTIONS OF THE SKELETAL SYSTEM  SUPPORT- provides rigidity which gives the body shape and supports the weight of the muscles and organs.  MOVEMENT- the skeletal bones are held together by ligaments, and tendons attach the muscles to the bones of the skeleton. The muscular and skeletal systems work together as the musculoskeletal system, which enables body movement and stability. When muscles contract, they pull on bones of the skeleton to produce movement or hold the bones in a stable position.  PROTECTION- The skeleton protects the internal organs from damage by surrounding them with bone. Bone is living tissue that is hard and strong, yet slightly flexible to resist breaking. The strength of bone comes from its mineral content, which is primarily calcium and phosphorus.  ACID- BASE BALANCE- maintaining normal blood pH is very important for maintaining homeostasis.  ELECTROLYTE BALANCE- bone serves as a reservoir for the electrolyte calcium, which is important for maintaining homeostasis.  BLOOD FORMATION- red blood cells, white blood cells, and platelets are produced by stem cells in the red bone marrow. HUMAN ANATOMY AND PHYSIOLOGY WITH THE SKELETAL SYSTEM PATHOPHYSIOLOGY  Lesson 1: Pathophysiology EFFECTS OF AGING ON THE SKELETAL SYSTEM The ratio of deposition and reabsorption changes as we age. In general, Deposition > Reabsorption Birth to age Increasing bone 25 mass and density Estrogen and Testosterone – hormones that serves as a lock on calcium in the bone. Deposition = Reabsorption Ages 24 to 45 Maintaining bone When the levels of these hormones are decreased, mass and density it is much easier for osteoclasts to reabsorb bone. Deposition < Reabsorption Ages 45 and Decreasing bone over The effects of the decreased bone mass and mass and density density with age are many:  Each vertebra becomes thinner.  The change in posture affects the gait and balance  Long bones lose mass but not length.  Scapulae thin and become more porous.  Joints stiffen and become less flexible as osteoarthritis sets in.  Mineral may deposit in joints.  Phalangeal joints lose cartilage, and the bones may thicken slightly. Ways to Reduce the Effects of Aging:  Proper Nutrition with ample Calcium and Vitamin D  Along with exercise FRACTURES ON THE SKELETAL SYSTEM A fracture is a break in bone. It can result from injury or trauma, like a fall, or it can result from a disease process that weakened the bone. X-ray can be used to view fractured bones. Types of Bone Fractures 1. Closed Fracture – (formerly called a simple fracture) does not cause a break in the skin. 2. Open Fracture – (formerly called a compound fracture) breaks through the skin. 3. Complete Fracture – the bone is in 2 or more pieces 4. Displaced Fracture – the bone is no longer in proper alignment. 5. Non-Displaced Fracture – the bone is in proper alignment. 6. Hairline Fracture – there is a crack in the bone. 7. Greenstick Fracture – the bone has broken through one side but not completely through the other side. 8. Depressed Fracture – the bone has been dented. 9. Transverse Fracture – the bone is broken perpendicular to its length. 10. Oblique Fracture – the break in the bone is at an angle. HUMAN ANATOMY AND PHYSIOLOGY WITH THE SKELETAL SYSTEM PATHOPHYSIOLOGY  11. Spiral Fracture – the break in the bone spiral ups in the bone. 12. Epiphyseal Fracture – the break occurs at the epiphyseal plate in a child. 13. Comminuted Fracture – the bone is broken into 3 or more pieces (commonly referred to as shattered) 14. Compression Fracture – may occur in the vertebrae, cancellous bone has been compressed. Fracture Healing A Closed Reduction – sets the edge of the fracture in proper alignment by manipulating the bone without surgery. An Open Reduction – sets the bone in proper alignment through surgery. DIAGNOSTIC TESTS FOR SKELETAL SYSTEM Common Diagnostic Tests for Skeletal System Diagnostic Test or Screening Description DEXA (dual-energy X-ray The use of low-dose absorptiometry) Scan radiation to measure bone Skeletal System Disorders density in the hip and Osteoporosis vertebrae “Porous Bones” X-ray The use of electromagnetic radiation that sends photons 👉 A severe lack of bone density. through the body to create a Breakdown of down ˃ Formation of new bones = visual image of dense porous bones structures such as bone 👉 It affects all bone but is more evident in cancellous bone. Causes: a diet deficient in calcium and vitamin D, lack of exercise, and diminished estrogen and testosterone due to aging. Effects: back pain, height loss, and Kyphosis or a hunched back Two types of Osteoporosis 1.) Postmenopausal – decrease estrogen level leads to increase bone resorption 2.) Senile – osteoblasts just gradually lose the ability to form bones while osteoclasts keep doing their thing unabated. Diagnostic tools such as X-rays, bone scans, and bone density tests can help diagnose osteoporosis and determine its severity. HUMAN ANATOMY AND PHYSIOLOGY WITH THE SKELETAL SYSTEM PATHOPHYSIOLOGY Osteomyelitis 👉 Is a bone infection that can reach the bone from the blood, from surrounding tissues, or from trauma that exposes the bone to a pathogen (such as a bacterium or fungus) 👉 The infection may be acute or it may be chronic. Treatment may include antibiotics and/or surgery to drain the area and remove damaged bone. Cancers Affecting the Skeletal System Osteosarcomas 👉 Are malignant bone tumors that occur in immature bone at any age. Although they tend to be more common in people between the ages of 10 and 15. It is usually found at the end of long bones, often around the knee. It is usually found at the end of long bones, often around the knee. Treatment: involves chemotherapy and surgery Chondrosarcomas 👉 Are cancerous tumors that occur in cartilage. Most chondrosarcomas are primary tumors, which means that they originate in cartilage, not from a tumor located in another organ or tissue within the body. Treatment: involves surgical removal of the tumor Gout 👉 is a form of inflammatory arthritis that develops in some people who have high levels of uric acid in the blood. The acid can form needle-like crystals in a joint and cause sudden, severe episodes of pain, tenderness, redness, warmth and swelling. Gout is commonly treated with anti-inflammatory drugs and colchicine, which helps relieve the arthritis symptoms. If necessary, health care professionals may also prescribe medications that help treat hyperuricemia. Cleft Palate 👉 an opening or split in the roof of the mouth that occurs when the tissue doesn't fuse together during development in the womb. A cleft palate often includes a split (cleft) in the upper lip (cleft lip) but can occur without affecting the lip. HUMAN ANATOMY AND PHYSIOLOGY WITH THE SKELETAL SYSTEM PATHOPHYSIOLOGY Risk factors 1. Family history. 2. Exposure to certain substances during pregnancy. 3. Having diabetes. 4. Being obese during pregnancy. Complications 1. Difficulty feeding. 2. Ear infections and hearing loss. 3. Dental problems. 4. Speech difficulties. 5. Challenges of coping with a medical condition. A cleft is usually treated with palate repair surgery. Other treatments, such as speech therapy and dental care, may also be needed. Mastoiditis 👉 is an infection of the mastoid process of the temporal bone in the skull. This condition is usually caused by an untreated middle-ear infection that has spread to the mastoid process. 👉 Symptoms include pain, fever, redness, tenderness and swelling near the mastoid process The infection is usually treated with antibiotics intravenously. If the infection has caused an abscess or pus- filled cavity to form within the mastoid process, surgery may be required to drain the infection. HUMAN ANATOMY AND PHYSIOLOGY WITH THE SKELETAL SYSTEM PATHOPHYSIOLOGY Bursitis Bursitis is inflammation of the bursa. Bursitis cause pain, tenderness, and swelling, especially with movement or pressure on the affected body part. Areas of the body commonly affected by bursitis are the knee, elbow, shoulder and hip. Arthritis Arthritis is an inflammation of a joint. There are more than 100 types of arthritis and some of them can affect other tissues beyond the joints. And according to the CDC arthritis is the most common cause of disability in the United States, with over 19 million adults affected. Osteoarthritis is the most common form of arthritis. It usually occurs in people over the age 40, and 85% of people over the age of 70 show some signs of this condition. Crepitus is the creaking sound that may be heard during the movement of osteoarthritic joints. Rheumatoid arthritis (RA) is an immune disease that can happen to anyone at any age. Children may develop juvenile RA. Osteogenisis imperfect - common called brittle bones - a congenital defect in which bones are lack of collagen fibers. With this defect, the bones are very brittle and can break easily. Rickets - is a childhood disorder in which an inadequate amount of mineral crystals is deposited in the bone. The bones are therefore too soft. HUMAN ANATOMY AND PHYSIOLOGY WITH THE SKELETAL SYSTEM PATHOPHYSIOLOGY