MSK3 bones & joints

• What are the four principal types of bones based on shape?


  Long bones, short bones, flat bones, irregular bones, and sesamoid bones
• Why are bones classified into different types?


  They are classified based on their shape and structure
• What is the defining characteristic of long bones?


  They have a greater length than width
• What are the components of long bones?


  One diaphysis and two epiphyses
• Which bones are classified as short bones?


  They are cubed shaped and nearly equal in length and width
• What is the texture of short bones?


  They have a spongy texture except at the surface, where there is a thin layer of compact bone
• What are flat bones primarily composed of?


  Two parallel plates of compact bone
• What is the function of flat bones?


  They provide considerable protection and extensive area for muscle attachment
• Which bones are classified as irregular bones?


  They have complex shapes and cannot be grouped into the other categories
• What is a characteristic of sesamoid bones?


  They are shaped like a sesame seed and form within a tendon or muscle
• What is the role of sesamoid bones?


  They alter the direction of pull of a tendon and provide a smooth surface for tendons to slide over
• What are sutural (Wormian) bones?


  Small bones between the joints of cranial bones that vary in number and size
• What is the general function of joints?


  They allow articulation and/or movement between bones
• How does the fit of bones affect joint strength and movement?


  The closer the fit, the stronger the joint but restricts movement; the looser the fit, the higher degree of movement but increases the risk of dislocation

  
• What are the three classifications of joints?


  Synarthroses, amphiarthroses, and diarthroses
• What are synarthroses joints?


  Immovable joints with fibrous tissue between the bones
• What are the three types of synarthrosis joints?


  Sutures, syndesmoses, and gomphoses
• What characterizes amphiarthroses joints?


  They are slightly movable joints that lack a cavity
• What are the two types of amphiarthroses joints?


  Synchondroses and symphysis
• What defines diarthrosis joints?


  They are freely movable joints with a joint space filled with synovial fluid
• What are the general structures of diarthrosis joints?


  Articular cartilage, synovial cavity, articular capsule, synovial fluid, and reinforcing ligaments
• What is the function of ligaments?


  They bind bones together to create joints
• How do ligaments differ from tendons?


  Ligaments contain more elastic fibers and are slightly more stretchy than tendons
• What is the maximum stretch percentage for ligaments?


  6% of their length
• What are tendons made of?


  Tendons are elastic tissue made up of collagen
• What is the primary function of tendons?


  To transmit the mechanical force of muscle contraction to the bones
• What are bursae and tendon sheaths associated with?


  Synovial joints
• What is the function of bursae?


  They reduce friction between adjacent structures during activities
• How many muscles are there in the human body?


  More than 600 muscles
• What percentage of a person's weight do muscles account for?


  About 40 percent
• How are skeletal muscles typically named?

  They often describe some feature of the muscle
• What are the primary functions of muscles?


  Movement, maintaining posture, stabilizing joints, generating heat, and moving substances
• What type of muscle is skeletal muscle?


  Striated and voluntary
• What is the primary role of cardiac muscle?


  To form most of the heart