CHAPTER 14 Lesson 1 SKELETAL SYSTEM Articulation Bursa Cancellous Cartilage Collagen Compact Degenerative Extremities Ligament Marrow Orthopedic Periosteum Resorption Synovial Tendon Journal question: What are the five functions of the skeletal system?

Chapter 14 Learning Objectives Define at least 10 terms relating to the skeletal system. Describe the five functions of the skeletal system. Identify at least 10 structures of the skeletal system.

Chapter 14 Learning Objectives Identify at least three methods of assessment of the skeletal system. Describe at least five disorders of the skeletal system.

Skeletal System The human body has more than 200 bones. Ask the students to name as many bones in the human body as they can. Write their answers on the chalk/white board.

Common Skeletal Bones Babies are born with more than 300 bones in their body. As we grow into adults, some of the bones grow together, and an adult skeleton has 206 bones. FIGURE 14-1 Common skeletal bones. A, Front view. B, Back view.

Structure and Function The skeletal system works directly with the muscular system to perform the following functions: Provide shape and support Protect internal organs Store minerals and fat Produce blood cells and platelets Assist in movement What role does the muscular system play in helping the skeletal system perform these functions? Have students give examples of each of these functions.

Bones Bone tissue contains Inorganic salts (calcium phosphate) Water Organic material (bone cells, blood vessels, nerves, and collagen) Bone cells must continually receive food and oxygen. Bone cells die and are replaced by new ones. Bones continue to grow for the first 18 to 20 years of life. Bones are alive! They are growing, living tissue. 99% of the calcium in your body is found in your bones and teeth.

Bones Bones may have cartilage. Bones are attached to other bones by ligaments. Bones are joined to muscles by tendons.

Types of Bones Two major groups of bones Axial skeleton Includes 80 bones of the head and trunk Appendicular skeleton Includes 126 bones of the pelvis, shoulders, arms, and legs How do the types bones found in the two major groups of bones differ?

Bones of the Body Ask students to name the biggest bone in the body. More than one half of the bones in the skeleton are found in the hands and feet. Each hand has 27 bones.

Bones by Shape Name a shape of a bone (long, short, flat, irregular), and have students give an example of a bone with that shape.

Skull Includes bones of the Cranium Eight bones Face 13 bones Ear The mandible is the only movable bone of the skull. The bones in the skull fit together like a jigsaw puzzle. The smallest bone is located in the ear, the stirrup bone, which is the size of a half a grain of rice. The strongest bone in the human body is the jaw bone.

Teeth Adults have 32 teeth. Each tooth has parts. The crown is the white section above the gum. The root is below the gum. Enamel, the hardest substance in the body, covers the crown. Cementum is the hard, bonelike substance covering the root. Dentin is located between the enamel and the pulp. The pulp is the soft living portion of the tooth, containing the nerves and blood vessels.

Tooth Development Teeth are the hardest substance in the human body. FIGURE 14-4 Tooth development

Parts of a Tooth FIGURE 14-5 Parts of a tooth. (From Bird DL, Robinson DS: Torres and Ehrich modern dental assisting, ed 7, Philadelphia, 2003, Saunders.)

Types of Teeth Four major types of teeth (each has a different shape and function): Incisor Cuspid Bicuspid Molar

Teeth Types

Thorax Thorax includes Ribs Sternum Vertebral bones Seven pairs of true ribs, five pairs of false ribs, and two pairs of floating ribs Sternum Vertebral bones Protect the lungs and heart Your ribs move about 5 million times per year, every time you breathe. Discuss the terms true ribs, false ribs, and floating ribs.

Thorax FIGURE 14-6 The thorax.

Vertebral Column Five parts (total of 26 vertebrae) Cervical vertebrae (7 vertebrae) Thoracic vertebrae (12 vertebrae) Lumbar vertebrae (5 vertebrae) Sacrum Coccyx Curvature gives it strength and flexibility. Cartilage between vertebrae cushions bones and allows movement.

Vertebral Column Adults have 26 vertebrae, and children have 33 vertebrae. In adults, five sacral bones form one bone, and four coccyx bones fuse to form one bone. FIGURE 14-7 The lateral view of the vertebral column shows its five major parts. These five parts contain a total of 26 vertebrae.

Long Bones of the Extremities Long bones of the arms and legs contain marrow, which produces blood cells. Long bones grow and lengthen from a layer of cartilage (epiphyseal plate). Shaft of the long bone (diaphysis) contains fatty tissue and yellow marrow. Fatty tissue provides stored energy. Ask students to name the long bones of the arms and legs and then discuss the slide.

Long Bones of the Extremities End of the long bone contains red marrow that produces red blood cells. Red marrow destroys old red blood cells, forms white blood cells, and produces platelets. Periosteum (membrane) Covers the bone Contains osteoblasts Medullary cavity Contains osteoclasts that enlarge the diameter of the cavity by removing bone cells. Every second, our bone marrow produces two million red blood cells.

Anatomy of a Long Bone FIGURE 14-8 The anatomy of a long bone.

Bone Markings Four major types of bone markings Projections bulge from a bone and attach to muscles, ligaments, and tendons. Openings are holes or spaces in bones. Depressions include openings and cavities in bone. Ridges are lines on a bone surface.

Bone Markings Discuss the types of bone markings.

Joints Articulation Joints are named by the bones that are joined. Two or more bones join together at a joint. Joints are named by the bones that are joined.

Types of Joints Three types of joints Immovable (synarthrosis) Example: sutures of the cranium Slightly movable (amphiarthrosis) Example: pelvic bones Freely movable (diarthrosis) Example: hip joint Discuss differences between these three types of joints. Discuss why the bones of the pelvis would be considered slightly movable. Have students pair off and locate examples of the three types of joints on each other.

Six Types of Diarthrotic Joints Ball-and-socket joints of the shoulders and hips Hinge joints of the elbow and knee Gliding joints of the wrists Pivot joint at the base of the skull Saddle joint of the thumb Gomphosis, such as the attachment of a tooth in its socket in the jaw

Six Types of Diathrotic Joints FIGURE 14-9 Types of joints. A, Ball and socket. B, Hinge. C, Gliding. D, Pivot. E, Saddle. F, Gomphosis.

Assessment Techniques Bone x-ray studies Bone marrow aspiration Bone marrow biopsy Radionuclide bone scan Computed tomography (CT) Magnetic resonance imaging (MRI) Bone densitometry Discuss assessment techniques. Ask students who have experienced any of the assessment techniques mentioned to talk about their expereince.

Disorders of the Skeletal System Ankylosing spondylitis Hereditary chronic spinal disease Arthritis Group of disorders evidenced by inflammation of a joint, pain, and stiffness during movement Avulsion fracture Occurs when a ligament or tendon pulls off part of a bone during an injury Bursitis Inflammation of the sac around a joint that is caused by trauma or irritation Discuss the causes, symptoms, treatment, and possible prevention of these disorders.

Disorders of the Skeletal System Caries Also called cavities, they are the major cause of tooth loss. Carpal tunnel syndrome Disorder caused by pressure on the median nerve of the wrist because of repetitive use or trauma Degenerative joint disease Also called osteoarthritis, it usually is associated with aging; it is the most common form of arthritis. Discuss the causes, symptoms, treatment, and possible prevention of these disorders.

Disorders of the Skeletal System Dislocation When bones move out of their proper location; usually occurs in the shoulder or hip Fracture Broken bone caused by trauma Gout Painful swelling of a joint that results from the buildup of uric acid crystals, most commonly in the great toe Discuss the causes, symptoms, treatment, and possible prevention of these disorders. A broken bone takes about 12 weeks to heal.

Disorders of the Skeletal System Herniated disk A ruptured or “slipped” disk between vertebrae Kyphosis Also called hunchback or humpback, it is an abnormal curvature of the thoracic part of the spine. Lordosis Also called swayback, it is an abnormal curvature of the lumbar spine. Discuss the causes, symptoms, and treatment of these disorders.

Disorders of the Skeletal System Meningomyelocele Also called spina bifida, it is a congenital condition of the spinal column. Osteoma Bone tumor Osteomalacia Also called rickets in children, it is softening of the bones caused by vitamin D and calcium deficiency. Discuss the causes, symptoms, and treatment of these disorders.

Disorders of the Skeletal System Osteomyelitis Bacterial infection of the bone Osteoporosis Weakening of the bones Paget’s disease Also called osteitis deformans, it is caused by excessive destruction of bone cells. Discuss the causes, symptoms, treatment, and possible prevention of these disorders.

Disorders of the Skeletal System Periodontitis Inflammation of the tissues that keep teeth in place Rheumatoid arthritis Pain and stiffness in the joints caused by thickening of the synovial membrane Rickets A painless deformity at the epiphysis of the bones caused by insufficient vitamin D Discuss the causes, symptoms, treatment, and possible prevention of these disorders.

Disorders of the Skeletal System Scoliosis Abnormal lateral spinal curvature Subluxation Partial dislocation of a joint, such as in the neck in a whiplash injury Talipes Congenital deformity involving the foot and ankle Discuss the causes, symptoms, treatment, and possible prevention of these disorders.

Issues and Innovations Progress in dental care Corrective measures, including bonding, bleaching, and implants • Bone substitutes and repairs Bone-replacing material, including organometals, ceramics, and coral Surgical implants for cranial and joint injuries Bone regeneration

Summary Functions of the skeletal system include protecting internal organs, storing minerals and fat, producing blood cells and platelets, and assisting in movement. The skeletal system is divided into the axial and appendicular skeletons, which include bones such as the cranium, humerus, femur, and ulna.

Summary Methods of assessment of the skeletal system include x-ray studies, bone marrow aspiration, biopsy (bx), CT, and MRI. Disorders of the skeletal system include avulsions, fractures, caries, carpel tunnel syndrome, and kyphosis.

Review Cervical, with regard to the skeletal system, pertains to: a. Between the ribs b. A study of the tooth c. Inflammation of the bones and joints d. The joints e. The neck

Review Cervical, with regard to the skeletal system, pertains to: a. Between the ribs b. A study of the tooth c. Inflammation of the bones and joints d. The joints e. The neck

Review Carpal tunnel syndrome is a(n): a. Group of disorders evidenced by inflammation of a joint, pain, and stiffness during movement b. Hereditary chronic spinal disease of unknown cause c. Condition that occurs when a ligament or tendon pulls off part of a bone during injury d. Inflammation of the sac around a joint caused by trauma or irritation e. Common disorder caused by pressure on the median nerve of the wrist resulting from repetitive use or trauma

Review Carpal tunnel syndrome is a(n): a. Group of disorders evidenced by inflammation of a joint, pain, and stiffness during movement b. Hereditary chronic spinal disease of unknown cause c. Condition that occurs when a ligament or tendon pulls off part of a bone during injury d. Inflammation of the sac around a joint caused by trauma or irritation e. Common disorder caused by pressure on the median nerve of the wrist resulting from repetitive use or trauma