Musculoskeletal

• Musculoskeletal system


  An organ system that enables an organism to move, support itself, and maintain stability during locomotion
• Musculoskeletal system


  • Its primary functions include supporting the body, allowing motion, and protecting vital organs
• Components of the musculoskeletal system


  • Bones (the skeleton)
  • Muscles
  • Cartilage
  • Tendons
  • Ligaments
  • Joints
  • Other connective tissue

  
• Muscles


  Contract (shorten) to move the bone attached at the joint
• Skeletal muscles


  Attached to bones and arranged in opposing groups around joints
• Types of muscles


  • Skeletal
  • Smooth
  • Cardiac
• Skeletal muscles


  • Under conscious control
• Skeletal muscle


  Composed of bundles of muscle fibers, or fasciculi

  
• Skeletal muscle


  Attached to bone by tendon, a strong fibrous cord

  
• Skeletal muscle movements


  • Flexion
  • Extension
  • Abduction
  • Adduction
  • External rotation
  • Internal rotation
  • Rotation
  • Pronation
  • Supination
  • Inversion
  • Eversion

  
• Skeletal system


  Serves as the main storage system for calcium and phosphorus
• Skeletal system


  Contains critical components of the hematopoietic (blood production) system
• Types of bone marrow


  • Yellow marrow
  • Red marrow
• Yellow marrow


  Has fatty connective tissue and is found in the marrow cavity, used for energy in times of starvation
• Red marrow


  Important site for hematopoeisis or blood cell production
• Skeleton


  Bony framework of the body

  
• Bone and cartilage


  Specialized forms of connective tissue
• Bone


  Hard, rigid, and very dense
• Joints


  Places of union of two or more bones
• Divisions of the skeleton

  • Axial skeleton
  • Appendicular skeleton

  
• Axial skeleton


  80 bones that form the vertical axis of the body, including the bones of the head, vertebral column, ribs and sternum

  
• Appendicular skeleton


  126 bones that include the free appendages and their attachments to the axial skeleton

  
• Types of bone cells


  • Osteoblasts
  • Osteoclasts
  • Osteocytes
• Musculoskeletal components


  • Nonsynovial or synovial joints
  • Muscles
  • Temporo-mandibular joint
  • Spine
  • Shoulder
  • Elbow
  • Wrist and carpals
  • Hip
  • Knee
  • Ankle and foot

  
• Nonsynovial joints


  Bones united by fibrous tissue or cartilage, either immovable or slightly movable
• Synovial joints


  Move freely because bones are separated and enclosed in a joint cavity filled with lubricating synovial fluid
• Synovial joints


  • Have a layer of resilient cartilage covering the surface of opposing bones, and are surrounded by a fibrous capsule and supported by ligaments
• Vertebrae


  • 7 cervical
  • 12 thoracic
  • 5 lumbar
  • 5 sacral
  • 3 to 4 coccygeal
• Spine

  Has four curves - cervical and lumbar are concave, thoracic and sacrococcygeal are convex
• Intervertebral disks


  Elastic fibrocartilaginous plates that cushion the spine and allow movement
• Temporomandibular joint (TMJ)


  Articulation of the mandible and temporal bone that allows jaw function of speaking and chewing
• TMJ syndrome is an abnormality of the temporomandibular joint
• Glenohumeral joint


  Articulation of the humerus with the glenoid fossa of the scapula, allowing mobility of the arm
• Rotator cuff


  Group of four muscles and tendons that support and stabilize the shoulder
• Elbow joint


  Contains three bony articulations - humerus, radius, and ulna - that allow flexion, extension, pronation and supination
• Wrist (radiocarpal) joint


  Articulation of the radius and row of carpal bones that allows movement in two planes
• Midcarpal joint


  Articulation that allows flexion, extension, and some rotation
• Metacarpophalangeal and interphalangeal joints


  Permit finger flexion and extension
• Flexion


  Bending a joint
• Extension


  Straightening a joint