Sciatic Notch (Greater)
Definition
Notch on the posterior border of the hip bone; wide and shallow in females (greater than 60 degrees), narrow and deep in males (less than 45 degrees).
- Location
- Posterior border of the hip bone (ilium/ischium junction)
- Female range
- Wide, typically greater than 60 degrees
- Male range
- Narrow, typically less than 45 degrees
- Assessment method
- Visual angle estimate or goniometer on the pelvis
- Reliability
- One of the most reliable single pelvic sex traits
Common questions
Why is the sciatic notch so reliable for sexing a skeleton?+
The pelvis carries the strongest sexual dimorphism in the human skeleton because it must accommodate childbirth in females, and the notch angle reflects that difference directly. Unlike cranial traits, which vary more with population and robusticity, the notch angle holds up well across ancestries.
What happens when the notch angle falls between 45 and 60 degrees?+
That intermediate range is ambiguous on its own and should not be scored in isolation. Examiners combine the notch with other pelvic indicators, such as the subpubic angle and preauricular sulcus, before assigning a sex estimate.
Does the notch angle work on a fragmented pelvis?+
It needs an intact notch margin to measure the angle accurately, so heavy fragmentation or erosion at the notch reduces its usefulness and pushes the examiner toward other surviving landmarks instead.
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