In the sexing of skeletal remains, the SINGLE MOST reliable bone for determining biological sex in an adult is:

• A Pelvis (os coxae) — based on the greater sciatic notch angle, subpubic angle, and sacral morphology ✓
• B Femur — based on neck angle and head diameter
• C Skull — based on brow ridge prominence and mastoid size
• D Sternum — based on sternal body-to-manubrium length ratio

Explanation

The pelvis (os coxae) is the most sexually dimorphic bone in the human skeleton due to reproductive adaptations in the female (wider subpubic angle >90°, broader greater sciatic notch, flatter iliac blade, wider true pelvis). Sex estimation from the pelvis alone achieves 95–98% accuracy. The skull is the second-most reliable (70–90% accuracy, based on brow ridges, mastoid process, nuchal crest, and mental protuberance). The femur head diameter (>47 mm = male) and long bone robusticity provide additional metrics. The sternum ratio has much lower reliability.

Reference: The Essentials of Forensic Medicine and Toxicology (Narayan Reddy), 34th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.