Muscles and Movement I: Joints

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Muscles and Movement IJoints

• DP Biology -- Feb 2009

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Basics of Human Movement
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Basics of Human Movement
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Basics of Human Movement
Antagonistic muscle pair extensor (straightens
joint) flexor (bends joint)
tendon
ligament
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Joints

• Point of contact between 2 or more bones
• Define possible range of motion
• Protect bones from damage due to friction

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Joint Structure

• Cartilage covers the ends of bones, absorbs
  shock,
• and reduces friction between the bones
• Synovial fluid lubricates the joint
• The joint capsule surrounds
• the joint and seals in the
• synovial fluid

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Joint Types
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Joint Types
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Elbow Joint
humerus
radius
ulna
The biceps and triceps are antagonistic. Which is
the extensor? The flexor?
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Elbow Joint
humerus
radius
ulna
The biceps and triceps are antagonistic. Which is
the extensor? triceps The flexor? biceps
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Elbow Joint
What kinds of joint make up the elbow? Hints
There are 2 .. .think about range of movements
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Elbow Joint
What kinds of joint make up the elbow?
Motions flexion, extension (hinge joint)
rotation (pivot joint)
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Hip Joint
What kinds of joint make up the hip?

• Ball socket joint
• Greatest range of motion
• flexion
• extension
• rotation
• abduction
• adduction

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FYI Osteoarthritis

• Gradual destruction of cartilage overtime
• Most common form of arthritis (over 21 million
  in US)
• Typically occurs in hands, hips, knees, and
  spine

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FYI Osteoarthritis

• Risk factors
• age
• weight
• gender (more
• common in women)
• heredity
• overuse / injury
• rheumatoid arthritis
• misformed bones

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FYI Osteoarthritis

• Treatments
• Reduction of stress on joints (losing weight,
  rest, frequent
• gentle exercise, braces, etc.)
• Pain management (NSAIDS, cortisone shots,
  etc.)
• Surgical treatments
• Debridement (cleaning ends of cartilage bones)
• Replacement (esp. with knee or hip)