Subpubic Contour/Concavity

Description: Phenice (1969:300) described the subpubic concavity as ‘‘a lateral recurve which occurs in the ischio-pubic ramus of the female a short distance below the lower margin of the pubic symphysis. . . [which] is absent in the male pelvis.’’ The concavity of the inferior female ischio-pubic ramus results in a greater subpubic angle where the two innominates articulate, and a generally more gracile form when compared with males. Klales et al. (2012) modified Phenice’s trait name to the subpubic contour and modified the description to include the entire length of the ramus rather than just the area below the symphyseal face.
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Scoring: The Phenice (1969) and Klales et al. (2012) article originally suggest scoring this trait in dorsal view; however, ongoing research suggests the trait is easier to score in ventral view, especially for less experienced observers. This trait should be scored with the bone in the same orientation as when the VA is being scored. If the ramus exhibits a marked concavity, it should be scored a 1 or 2, while if a convexity is noted the specimen should be scored a four or five (even if a small concavity is noted just below the symphyseal face- see images).

1. Well-developed concavity present inferior to symphyseal face and along most of the length of the inferior ramus.
2. Slight concavity present inferior to symphyseal face that extends partially down inferior ramus.
3. Bone is nearly straight along the entire length of ischio-pubic ramus with no obvious concavity or convexity observable. A very slight indentation may exist just inferior to the symphyseal face.
4. Slight convexity, especially pronounced along the middle portion of the inferior ramus. A very slight indentation may exist just below the symphyseal face and/or along the lower third; however, middle portion of ramus is convex.
5. Well-developed convexity, pronounced along the entirety of the inferior ramus.