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Anatomy and Physiology Module

• Module Title: Anatomy - Physiology
• Course Level: First year of general nursing
• Academic year: 2023-2024
• Course Duration: 100 hours (lectures)
• Learning materials: Slides
• Teaching team: Dr. Oussama Aazzane

The Locomotor System

• Definition: The locomotor system is a functional unit made up of bones, articulations, muscles, and nerves
• Components: Bones, joints, muscles, nerves
• Functions: Support, movement, protection of internal organs.

Osteology

• Definition: The study of bones and their pathologies
• Bone tissue:
  • Contains 22-25% water
  • Organic components (bone cells)
  • Inorganic components (primarily calcium phosphate which forms the bone's mineral matrix)

Functions of the Skeletal System

• Support: The skeleton provides a framework that supports soft tissues and organs
• Protection: The skeleton protects vital organs
• Movement: The skeleton, in conjunction with muscles and joints, allows for movement.
• Mineral storage: The skeleton stores calcium and phosphorus, essential for various bodily functions
• Blood cell formation: Bone marrow produces blood cells.

External Configuration of Bones

• Bone types:
  • Flat bones
  • Long bones
  • Short bones
  • Irregular bones
• Examples: bones of the skull, the wrist, the thigh, and the spine

Structure of Long Bones

• Parts of long bones
  • Epiphyses (bone ends, containing red bone marrow)
  • Diaphysis (shaft, containing yellow bone marrow)
  • Articulating cartilages (help bones glide at joints)
  • Compact bone
  • Spongy (cancellous) bone
  • Periosteum (membrane covering outside the bone)
  • Medullary cavity (contains bone marrow, and osteoblasts and osteocytes)
  • Endosteum(covers the medullary cavity)

Functions of Skeletal Structures

• Bone marrow:
  • Red marrow: produces blood cells (hemopoiesis)
  • Yellow marrow: Stores fat
• Bone structure: Supports body weight and facilitates movement
• Periosteum: Encloses the bone
• Cartilage: Reduces friction between bones at joints.

Functions of Bones

• Movement: Bones act as levers for muscles.
• Mineral storage: Calcium and phosphorus are stored in bones.
• Hematopoiesis: Blood cell formation occurs in bone marrow.
• Protection: Internal organs are protected from damage.

Growth of Bones

• Bone growth: Bone growth occurs throughout childhood and adolescence.
• Closure of growth plates: The growth plates close at different ages in different sexes.

Microstructure of Bone

• Bone matrix:
  • Organic component (Mostly collagen)
  • Inorganic component (Mostly hydroxyapatite crystals)
• Bone cells:
  • Osteoblasts: Produce bone matrix
  • Osteocytes: Maintain bone matrix
  • Osteoclasts: Break down bone matrix
• Compact bone: Dense bone that provides strength
• Cancellous bone: Spongy bone, found in the epiphyses of long bones, and other bones
• Bone marrow: Red or yellow
• Osteocytes: embedded in mineralized matrix

Bone and Nutrition

• Calcium: Essential for bone health and strength
• Phosphorus: Essential for bone health and strength
• Vitamin D: Aids in calcium absorption
• Vitamin C: Important in collagen production

Bone Development

• Intramembranous ossification: Forms flat bones like the skull.
• Endochondral ossification: Forms long bones from hyaline cartilage models

Skeletal Structures

• Axial skeleton: The central axis of the body, which includes the skull, vertebral column, and rib cage.
• Appendicular skeleton: The bones of the limbs and their attachment points, such as the shoulder and hip girdle.

Skull

• Cranial bones: Skull bones that enclose and protect the brain
• Facial bones: Support the face and structures in the face

The Thoracic Cage

• **Sternum:**A flat bone located in the center of the anterior chest wall
• Ribs: A set of 12 pairs of bones that form the rib cage and enclose and support the organs in the chest
• Costal cartilages: Hyaline cartilages that connect the ribs to the sternum.

Vertebral Column

• Number of vertebrae: 33 vertebrae, divided in several sections
• Vertebral sections: Cervical, thoracic, lumbar and sacral, and coccyx.

Appendicular Skeleton

• Upper limb: The arms (humerus, radius, ulna, carpals, metacarpals, phalanges)
• Lower limb: The legs (femur, tibia, fibula, tarsals, metatarsals, phalanges)
• Pectoral girdle: Attaches the upper limb to the axial skeleton.
• Pelvic girdle: Attaches the lower limb to the axial skeleton.

Movements of the Vertebral Column

• Flexion: Bending forward.
• Extension: Bending backward.
• Lateral flexion: Bending sideways.
• Rotation: Twisting.