BMS100 Guide to Orienting Limb Bones
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For the Lab Quizzes on the bones of the limbs, you will be asked to name bones and their special features, and to distinguish between bones from the right side of the body and those from the left side. While the "right or left?" questions will constitute only one half of one point each, and you will receive credit for the correct names of the bones, knowing the side of the body from which an individual bone came proves that you really know the skeleton. Following is a guide to orienting the bones of the appendicular skeleton with respect to "rights and lefts."
  • scapula (p. 147)
    • scapular spine is on the posterior (back) side of the scapula
    • glenoid cavity must be superior and lateral (up and out)
    • infraspinous fossa (large area inferior to the spine) is larger than the supraspinous fossa

  • clavicle (p. 147)
    • sternal end (the larger, "lumpy" end) is medial (toward the body midline)
    • smoother surface is superficial (closer to the skin)
    • starting from the sternal end, the clavicle curves anteriorly (toward the front) first, then it curves posteriorly (back)
      •
  • humerus (p. 148)
    • head is directed superiorly and medially (up and in)
    • medial epicondyle - this large "lump" is directed medially (toward the midline of the body)
    • olecranon fossa is on the posterior (back) side so as to receive the olecranon of the ulna when the forearm is extended

  • radius (p. 149) is always on the "thumb side" of the forearm
    • head - is superior (up)
    • styloid process - points toward the thumb
    • the smoother surface of the distal (far end of the) radius faces anteriorly (forward) when the forearm is supinated (when the palms face anteriorly)

  • ulna (p. 149) is always on the fifth (little) finger side of the forearm
    • olecranon process and trochlear notch are superior
    • radial notch contacts the head of the radius and therefore must face laterally (outward) because the radius is lateral to (to the outside of) the ulna
PELVIC GIRDLE (p. 151)
  • ilium
    • iliac crest is superior and lateral (up and out)
    • iliac fossa faces medially (inward)

  • ischium
    • ischial tuberosity is inferior (faces down): it's the "sitting bone"

  • pubis is anterior


  • additional pelvic girdle features
    • acetabulum - on inferior/lateral part of os coxa
    • symphysis pubis is the most anterior (in front) part of the pelvis
    • obturator foramen is inferior and anterior (on the lower part of the front side)


  • femur (p. 153)
    • head projects superiorly and medially (up and in)
    • greater trochanter is lateral (on the outside)
    • gluteal tuberosity is posterior (on the backside)
    • the femur has a curvature similar to that of the entire thigh: anterior (front) side is convex, posterior (back) side is concave

  • patella: has a lump on the medial (inner) side and a larger facet (surface) on the lateral posterior surface


  • tibia (p. 153)
    • tibial tuberosity and anterior crest are on the anterior (front) side
    • medial malleolus is the "lump" on the medial (inner) side of the ankle

  • fibula (p. 153)
    • head is a bit rounder than the lateral malleolus and is positioned proximally (closer to the knee)
    • lateral malleolus is the "lump" on the lateral (outer) side of the ankle; it's smoother surface is superficial (closer to the skin) and the lateral malleolus points inferiorly and posteriorly (down and back)
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Fall 2008