1. A method for determining an orientation of one or more extremities comprising: receiving a depth image; generating a grid of voxels based on the depth image; removing a background included in the grid of voxels to isolate one or more voxels associated with a human target; defining a head-to-center vector based on locations or positions of a head and a center of the human target; creating an extremity volume box based on a displacement along the head-to-center vector; and determining the orientation of the one or more extremities based on a line fit of depth values within the extremity volume box.