Figure 5.

Euler angle results for the right ninth male rib. (a) Euler angle about the l-axis changes from −1.56° at age 20 to −5.64° at age 90, resulting in rotation of the rib in the superior-medial direction. (b) Euler angle about the m-axis changes from −0.25° at age 20 to 5.21° at age 90, resulting in rotation of the rib in the superior direction. (c) Euler angle about the n-axis changes from −0.87° at age 20 to −3.19° at age 90, resulting in rotation of the rib in the medial direction within the local rib plane defined by the anterior, lateral, and posterior landmarks. (d) Resulting configurations of the 20- and 90-year-olds when applying all three Euler angle rotations to the right ninth male rib.