Anatomy and Physiology of the body including musculoskeletal system and others

Anatomy and physiology of the body system including the musculoskeletal system, the spine and thorax.

1. FREEDOM EMENALO Presents Part ii

2. ANATOMY AND PHYSIOLOGY PART 1 SECTION 2 THE MUSCULOSKELETAL SYSTEM The musculoskeletal system is a complex arrangement of levers and fulcrums that provides motion and support for the body. It consists of the skeleton and the muscles. The skeleton is the human body’s superstructure, while the muscles supply the power of motion to this superstructure, the organs, and the other body components.

3. FUNCTION OF THE SKELETON It serves five important purposes: It gives the body its structural form. It protects the vital organs. It allows for efficient movement despite the forces of gravity. It stores many salts and other materials needed for metabolism. It produces the red blood cells used to transport oxygen.

4. BONE STRUCTURE The structure of a bone consists of minute blood vessels that travel lengthwise along the bone through small tubes, called haversian canals. bone cells maintain a dynamic and efficient structure for supporting and moving the body. The major areas and tissues of the long bones include the diaphysis, the epiphysis, the metaphysis, the medullary canal, the periosteum , and the articular cartilage.

5. TYPES OF JOINTS Joints are categorized based on the movements they allow. Monaxial joints : these are Hinge joints which permit bending in a single plane. Examples include the knees, elbows, and fingers. Pivot joints are characterized by the articulation between the atlas (the first cervical vertebrae) and the axis of the spine. They allow the head to rotate through about 180 degrees of motion.

6. TYPES OF JOINTS Biaxial joints : these are Condyloid , or gliding , joints which provide movement in two directions. They are located at the joints of carpal bones in the wrist and between the clavicle and sternum. Ellipsoidal joints which provide a sliding motion in two planes, as between the wrist and the metacarpals. Saddle joints which allow for movement in two planes at right angles to each other. Examples are the joints at the bases of the thumbs.

7. TYPES OF JOINTS Triaxial joints: this is a Ball-and-socket joints permit full motion in a cone of about 180 degrees and allow a limb to rotate. Examples include the hip and shoulder. These joints permit various types of motion. Flexion/extension is the bending motion that reduces/increases the angle between articulating elements. Adduction/abduction is the movement of a body part toward/away from the midline. Rotation refers to a turning along the axis of a bone or joint. Circumduction refers to movement through an arc of a circle.

8. SKELETAL ORGANIZATION The human skeleton is made up of approximately 206 bones. These bones form two major divisions, the axial and the appendicular skeletons. The axial skeleton consists of the bones of the head, thorax, and spine. These bones form the axis of the body, protect the elements of the central nervous system, and make up the thoracic cage. The appendicular skeleton consists of the bones of the upper and lower extremities, including both the shoulder girdle and the pelvis, and excepting the sacrum. These bones provide the structure for the extremities and permit the major articulations of the body.

9. THE EXTREMITIES The extremities are the arms and legs, including the wrists and hands, elbows, shoulders, ankles and feet, knees, hips, and pelvis.

10. THE EXTREMITIES Wrists and Hands The radius and ulna articulate with the carpal bones at the wrist, or radiocarpal joint. The carpals articulate with the metacarpals. The metacarpals articulate with the proximal phalanges at the metacarpophalangeal (MCP) joint. The proximal phalanges articulate with the middle phalanges at the proximal interphalangeal (PIP) joint.

11. THE EXTREMITIES Elbows The lateral and medial epicondyles (large rounded edges) of the distal humerus , the olecranon process of the proximal ulna, and the proximal radius comprise the elbow joint. The elbow is a hinge joint, allowing flexion and extension. The major flexor muscles are the biceps. The major extensor muscles are the triceps. Just below the elbow, the relationship of the radius and ulna to the pronator and supinator muscles allows the forearm to supinate (turn palm up) and pronate (turn palm down).

12. THE EXTREMITIES Shoulders The shoulder girdle consists of articulations between the clavicle and the scapula and between the scapula and the head of the humerus . The sternoclavicular joint , which joins the clavicle and the manubrium, is the only bony link between the upper extremity and the axial skeleton. The distal clavicle articulates with the acromion, or acromion process, of the scapula at the acromioclavicular (AC) joint . The glenohumeral joint is a ball-and-socket joint that allows flexion, extension, internal and external rotation, abduction, and adduction.

13. THE EXTREMITIES Ankles and Feet The foot comprises 7 tarsal bones, 5 metatarsal bones, and 14 phalanges. The talus, the calcaneus (heel), and the other tarsals articulate in a system of joints that allows inversion (lifting the inside of the foot) and eversion (lifting the outside of the foot). The most distal tarsals articulate with the metatarsals, which articulate with the proximal phalanges at the metatarsophalangeal joints.

14. THE EXTREMITIES Knees The knee joint involves the distal femur, the proximal tibia, and the patella. The knee is a modified hinge joint, allowing flexion and extension, with some rotation during flexion. The major flexors are a group of three muscles (biceps femoris , semimembranosus, and semitendinosus) known as the hamstrings . The major extensors are a group of four muscles ( vastus lateralis , vastus intermedius , vastus medialis , and rectus femoris ) known as the quadriceps .

15. THE EXTREMITIES Hips and Pelvis The hip is the juncture of the lower extremities with the pelvis. The pelvis is a strong skeletal structure consisting of two symmetrical structures called the innominates . Each innominate is formed from the ilium , ischium and the pubis , all fused together.

16. BONE AGING Bones of the young child remain flexible and do not reach maximum strength until early adulthood. While each bone matures at a different time, almost all maturation is complete by 18 to 20 years of age. Around the age of 40, the body begins to lose its ability to maintain the bone structure. It is unable to rebuild the collagen matrix and the deposition of salt crystals is reduced from what it was in earlier years.

17. MUSCULAR TISSUE AND STRUCTURE More than 600 muscle groups make up the muscular system. A large number of EMS calls involve injuries to this muscular system. Injuries to it may result from, either blunt or penetrating. There are three types of muscle tissue within the body: Cardiac Smooth Skeletal

18. THE HEAD, FACE, AND NECK THE HEAD The head is made up of three structures that cover the brain: the scalp ,the cranium ,and the meninges . Each of these structures provides essential protection from the environment and from trauma.

19. THE HEAD The Scalp The scalp is a strong and flexible mass of skin, fascia (bands of connective tissue), and muscular tissue. The scalp is also extremely vascular in order to help maintain the brain at the body’s core temperature. Scalp hair further insulates the brain from environmental temperatures and, to a lesser degree, from trauma. The scalp is only loosely attached to the skull and is made up of the overlying skin and a number of thin layers of muscle and connective tissue underneath.

20. THE HEAD The Cranium The bony structure supporting the head and face is the skull. It can be subdivided into two components, the cranium, and the facial bones that form the skeletal base for the face. The cranium actually consists of several bones fused together at pseudojoints called sutures . The cranial vault, however, provides very little space for internal swelling or hemorrhage,

21. THE HEAD The Meninges The final protective mechanisms for the brain and the spinal cord are the meninges. They are three layers of tissue that lie between the cranium and the brain and also between the spinal column and the spinal cord. The outermost layer is the dura mater. The meningeal layer closest to the brain and spinal cord is the pia mater . Separating the two layers of mater is arachnoid membrane

22. THE HEAD Cerebrospinal Fluid Cerebrospinal fluid is a clear, colorless solution of water, proteins, and salts that surrounds the central nervous system and absorbs the shock of minor acceleration and deceleration. The brain constantly generates cerebrospinal fluid in the largest two of four spaces (or ventricles) within the substance of the brain. The fluid circulates through the ventricles, then through the subarachnoid space.

23. THE HEAD The Brain The brain occupies about 80 percent of the interior of the cranium. It is made up of three major structures essential to human function—the cerebrum, the cerebellum, and the brainstem.

24. THE HEAD, FACE, AND NECK FACE Facial bones make up the anterior and inferior structures of the head and include the zygoma , maxilla , mandible , and nasal bones. The Ear: The outer, visible portion of the ear is termed the pinna. It is composed of cartilage and has a poor blood supply. It connects to the external auditory canal, which leads to the eardrum The Eye : The eye is a spherical globe, filled with liquid. Its major compartment (the posterior chamber) contains a crystal-clear gelatinous fluid called vitreous humor

25. THE HEAD, FACE, AND NECK NECK The neck is the region that links the head to the rest of the body. Traveling through this anatomical area are blood for the facial region and brain, air for respiration, food for digestion. The neck also contains some of the important muscles used to provide head and shoulder movement as well as the thyroid and parathyroid glands of the endocrine system.

26. THE SPINE AND THORAX THE SPINE The spine consists of a supporting skeletal structure, the vertebral column , and a central nervous system pathway, the spinal cord. The vertebral column provides skeletal support for and permits movement of the head, assists in maintaining the shape of the thoracic cage, supports the upper body, and forms the posterior aspect of the pelvis. spinal cord is responsible for transmitting messages from the brain to the body organs and tissues and from the sensory nerves in the organs, skin, and other tissues back to the brain.

27. Divisions of the Vertebral Column The vertebral column is divided into five regions: the cervical, the thoracic, the lumbar, the sacral, and the coccygeal. The individual vertebrae of the column are identified by the first letter of their region and numbered from superior to inferior. For example, the most inferior of the seven cervical vertebrae is identified as C-7.

28. Divisions of the Vertebral Column Cervical Spine The cervical spine consists of seven cervical vertebrae located between the base of the skull and the shoulders. The first cervical vertebra, C-1, is called the atlas and it supports the head. Vertebra C-2, called the axis , provides a pivotal point around which the atlas and head can rotate from side to side.

29. Divisions of the Vertebral Column Thoracic Spine The thoracic spine consists of 12 thoracic vertebrae.

30. Divisions of the Vertebral Column Lumbar Spine The five bones of the lumbar spine each carry the weight of the head, neck, and thorax above them. They also bear the forces of bending and lifting above the pelvis.

31. Divisions of the Vertebral Column Sacral Spine The sacral spine consists of five sacral vertebrae that fuse into the posterior plate of the pelvis. This plate, in conjunction with the two innominate bones of the pelvis, protects the urinary and reproductive organs and attaches the pelvis and lower extremities to the axial skeleton.

32. Divisions of the Vertebral Column Coccygeal Spine The coccygeal spine is made up of three to five fused vertebrae that represent the residual elements of a tail. They comprise the short skeletal end of the vertebral column.

33. THE SPINE AND THORAX THE THORAX The thoracic cage is the chamber that moves air in and out and where oxygen and carbon dioxide are exchanged to support the body’s metabolism. It consists of the thoracic skeleton , diaphragm , and associated musculature . It is also the location of the heart, major blood vessels, and other important structures essential for body function. It contains the trachea, bronchi, lungs, and the mediastinum.

34. THE THORAX The Thoracic Skeleton The thoracic skeleton is defined by 12 pairs of C-shaped ribs, which articulate posteriorly with the thoracic spine and then extend in an anterior and inferior direction. The upper seven pairs join the sternum at their cartilaginous endpoints. The 8th through 10th ribs have cartilage at their distal anterior ends that join the cartilage of the 7th rib at the inferior margin of the sternum. The 11th and 12th ribs are often termed the floating ribs and have no anterior attachment.

35. THE THORAX The Thoracic Skeleton The sternum completes the anterior bony structure of the thorax and is made up of three sections: the manubrium , the body of the sternum, and the xiphoid process . The manubrium is the superior portion of the sternum.

36. THE THORAX The Diaphragm The diaphragm is a muscular, domelike structure that separates the abdominal cavity from the thoracic cavity. The diaphragm is a major muscle of respiration.

37. THE THORAX Great Vessels The great vessels are those large arteries and veins that enter and leave the heart and are found in the mediastinum. They are the aorta, the superior and inferior vena cava, the pulmonary arteries, and the pulmonary veins.

38. Thank You For Listening QUESTIONS

39. References Bledsoe , B. E., Cherry, R. A., & Porter, R. S. (2014). Essentials of Paramedic Care Update. Second Edition Pearson New International Edition. Anatomy & Physiology P(129-206). Sanders, M. J., Lewis, L. M., Quik , G., & McKenna, K. (2012). Mosby ’ s Paramedic Textbook. Fourth Edition. St. Louis, Mo., Elsevier/Mosby Jems . Anatomy & Physiology P(146-209).