Joints, Movements & Muscles

• Functions of the Skeleton

  • protection
  • movement
  • mineral storage
  • support & protection
  • blood cell production
• Types of Bones

  • long - longer than they are wide (femur)
  • short - usually square in shape (carpals)
  • flat - flat & curved (cranium)
  • irregular - odd shapes (vertebrae)
  • sesamoid (patella)
• Joint

  a place where 2 or more bones meet
• Joints

  • neck (cranium, vertebral column)
  • shoulder (scapula, humerus)
  • chest (ribs, sternum)
  • elbow (humerus, radius, ulna)
  • hip (pelvis, femur)
  • knee (patella, tibia, femur)
  • ankle (fibula, tibia, talus)
• Structure & Function of Synovial Joints

  • ligament - tough band of slightly elastic connective tissue, connects bone to bone, stabilises joints during movement
  • synovial fluid - lubricating liquid contained within joint cavity, helps us move freely, reduces friction
  • articular cartilage - smooth tissue which covers the surface of articulating bones, cushioning prevents friction, absorbs shock
  • joint capsule - fibrous sac with an inner synovial membrane, encloses & strengthens joint
  • bursa - fluid filled sac where tendons rub over bones, reduces friction between bones & tendons
• Types of Synovial Joint

  • ball & socket
  • hinge
  • pivot
  • condyloid
  • gliding
• Ball & Socket Joints

  allows movements in all directions & are the most mobile joints in the body

  
  

  shoulder, hips
• Hinge Joints

  only allows forwards & backwards movement, like a hinge on a door

  knee, elbow, ankle
• Pivot Joints

  have a ring of bone that fits over a bone sticking out, allows rotation only

  neck, radio ulna joint
• Condyloid Joints

  oval shaped bone end fits into a similar shape, allows small movement in all directions

  between carpals & metacarpals in wrist
• Gliding Joints

  occurs between the surfaces of 2 flat bones that are held together by ligaments

  bones in wrist & ankles
• Types of Movement

  • flexion & extension
  • plantar flexion &dorsi flexion
  • abduction & adduction
  • horizontal flexion & extension
  • circumduction
  • rotation (lateral & medial)
• Flexion

  a decrease in the angle that occurs around a joint

  e.g upwards phase of bicep curl
• Extension

  an increase in the angle that occurs around a joint

  e.g downwards phase of bicep curl
• Plantar Flexion

  bending the foot downwards away from the tibia

  e.g dancer pointing their toes
• Dorsi Flexion

  bending the foot upwards towards the tibia

  e.g runners running with flexed feet
• Abduction

  movement away from the midline of the body

  e.g upwards phase of star jump
• Adduction

  movement towards the midline of the body

  e.g downwards phase of star jump
• Horizontal Flexion

  movement of the arm across the body in the transverse plane

  e.g forehand shot in tennis
• Horizontal Extension

  movement of the arm away from the body in the transverse plane

  e.g backhand shot in tennis
• Circumduction

  circular movement of a body part

  e.g cricket bowl
• Medial/Lateral Rotation

  medial - movement out

  lateral - movement out
• Planes of Movement

  • frontal
  • transverse
  • sagittal
• Frontal Plane

  • perpendicular to ground
  • divides body into anterior & posterior
  • abduction & adduction
• Transverse Plane

  • divides body into top & bottom
  • rotation, pronation, suspination
• Sagittal Plane

  • divides body into left & right
  • flexion & extension