Stress distribution in the scapula studied by neutron diffraction.
High intensity neutron beams provide a method of measuring the preferred orientation of apatite crystals in bulk samples of bone. Measurements at seven different sites on the scapula show that the c axes of the crystals lie preferentially along the directions of pull of the attached muscles. The highest orientation is found at positions under the influence of only a single group of muscles, such as M. teres major or M. infraspinatus. In intermediate regions a multiple distribution of crystals is found, able to withstand stresses in more than one direction. The technique provides a method of assessing the distribution of stress in bones.
D000818:Animals; D001031:Apatites / Q000032:analysis; D001842:Bone and Bones / Q000648:ultrastructure*; D009501:Neutron Activation Analysis; D012540:Scapula / Q000648:ultrastructure*; D013314:Stress, Mechanical
D001031:Apatites