Home » Forensic Medicine and Toxicology » Sex Differences in Bones

Sex Differences in Bones

Sex of an unidentified skeleton may be determined from the differences in the bones among males and females.

Krogman’s Sex Determination from Skeleton
Entire skeleton 100% accuracy
Pelvis only 95% accuracy
Skull and pelvis 98% accuracy
Skull only 92% accuracy
Pelvis and long bones 98% accuracy
Long bones only 80% accuracy

a.       Subjective Sex Determination

e.g. From morphology of bones

b.      Objective Sex Determination

e.g. From pelvic indices

Pelvic Sex Differences

  Males Females
Pelvic cavity Longer and more conical Shorter and more cylindrical
Dimensions Greater Less
Markings for muscles and ligaments More prominent Less prominent
General architecture Stouter and heavier Lighter
Pelvic brim Heart shaped More circular or elliptical
Anterior pelvic wall More in height Lesser in height
Sub pubic arch or angle More angular (50-60 degrees) U shaped (80-85 degrees)
Pelvic Indices

Sacral Index = Sacral breadth/Sacral length x 100

Male = 105%

Female = 115%

Ischium Pubis Index = Pubis length/ Ischium length x 100

In Negroes

  • Male < 84
  • Female > 88


  • Male < 90
  • Female > 95


Iliac crest More rugged and curves medially more acutely at anterior end Less curved
Iliopectineal line Less vertical More vertical
Pre-auricular sulcus Less marked Well marked
Body of pubis bearing symphyseal surface Triangular in shape Quadrangular in shape


Ischial spine In turned Out turned
Ischiopubic rami Distinctly roughened area for attachment of crus penis Attachment of clitoris poorly developed
Acetabulum Larger Smaller
Obturator foramen Ovoid and larger Triangular
Greater sciatic notch   Wider


  Longer and narrower Shorter and wider
  More massive Less massive and smooth
Dorsal convexity Less  prominent More prominent
  Over 5 segments due to addition of a lumbar or coccygeal vertebra  
Auricular surfaces for articulation with ilium Longer Shorter
Articular facet 1/3 of width of base Less than 1/3 in female


Length Longer Shorter
Weight Heavier Lighter
Texture Rough Smooth
Muscle markings More developed Less developed
Shaft Less oblique More oblique
Head of femur Larger Smaller
Linea aspera More marked Less marked
Trochanters More prominent Less prominent
Femoral neck angle More (>125) Less (<125)

Generally sternal body is more than twice the length of manubrium in males and less than twice in females.


Until age of puberty there is little difference.

  Heavier and larger Lighter and smaller
Capacity More 10% less
Walls Thicker Thinner
Muscular ridges More marked Less marked
Glabella, superciliary arch and mastoid process Well marked Less marked
Air sinuses More prominent Less prominent
Upper margin of orbit Smoother Sharper
Orbital shape Squarer or rectangular Round
Forehead Less vertical More vertical
Fronto-nasal angulation Distinct Less distinct
Cheek bones Heavier and more laterally arched Lighter

Lower Jaw

  More massive Less massive
Rami More broad Less broad
Angle region Everted  
Chin Squarer More rounded

Check Also

Electric Injuries (Electrocution)

Damage to the tissues due to the passage of electric current is called electrical injury. …

Leave a Reply

Your email address will not be published. Required fields are marked *