Foot bones allow researchers to determine sex of skeletal remains

February 29, 2012
The tarsals are the bones that make up the ankle, heel and rear part of the arch in a human foot. Researchers have developed means of determining the biological sex of partial skeletal remains using these bones. Credit: Troy Case, North Carolina State University

Law enforcement officials who are tasked with identifying a body based on partial skeletal remains have a new tool at their disposal. A new paper from North Carolina State University researchers details how to determine the biological sex of skeletal remains based solely on measurements of the seven tarsal bones in the feet.

"Tarsals are fairly dense bones, and can be more durable than other bones – such as the pelvis – that are used to determine biological sex," says Dr. Troy Case, an associate professor of anthropology at NC State and co-author of a paper describing the research. "Also, the tarsal bones are often enclosed in shoes, which further protects them from damage. That's particularly useful in a forensic context." The tarsals are the seven bones that make up the ankle, heel and rear part of the arch in a human foot.

Researchers looked at the tarsal bones of 160 men and women of modern European-American descent, taking length, breadth and height measurements for each bone, with the exception of the calcaneus. For the calcaneus, or heel bone, researchers measured only its length.

Previous studies had shown that the talus – or ankle bone – and calcaneus can be fairly good indicators of biological sex. However, little research had been done on the other tarsal bones, which are significantly smaller.

The researchers found that the tarsal bones of the right foot are generally more reliable indicators for determining biological sex. For example, the length of the talus on the right foot correctly determined biological sex 90 percent of the time.

However, a single measurement can be misleading. For example, a woman may be particularly tall, or a man particularly short. So the researchers looked at combinations of measurements from multiple bones, which allow them to measure the relative size of the bones to each other.

For example, researchers found that looking at the height of the talus along with the length of the third cuneiform bone – in the center of the foot – allowed them to determine the biological sex of a skeleton with 93.6 percent accuracy.

While the research has clear forensic science applications, it may also help researchers studying ancient populations. "We evaluated remains of modern European-Americans, so our findings are not directly applicable to ancient populations," Case says. "However, it does tell us which tarsal bones are most indicative of biological sex. So, if you have a large number of skeletons, and some of them can be sexed based on skull or pelvis measurements, you could use the information we've provided on tarsals to create equations for sexing the other in that group based solely on tarsal ."

Explore further: Ancient mammoth bones found in Florida

More information: The paper, "Sexual Dimorphism in the Tarsal Bones: Implications for Sex Determination," will appear in the March issue of the Journal of Forensic Sciences.

Related Stories

Scavenger birds chew the fat

September 8, 2008

Humans aren't the only ones who like fatty foods - bearded vultures do, too. A study by Antoni Margalida from the Bearded Vulture Study and Protection Group in El Pont de Suert, Spain, has found that the bearded vulture will ...

Study finds that overweight people really are big-boned

March 22, 2011

( -- One of the blind spots in forensic science, particularly in identifying unknown remains, is the inability of experts to determine how much an individual weighed based on his or her skeleton. New research ...

Recommended for you

The dark side of Nobel prizewinning research

October 4, 2015

Think of the Nobel prizes and you think of groundbreaking research bettering mankind, but the awards have also honoured some quite unhumanitarian inventions such as chemical weapons, DDT and lobotomies.

How much for that Nobel prize in the window?

October 3, 2015

No need to make peace in the Middle East, resolve one of science's great mysteries or pen a masterpiece: the easiest way to get yourself a Nobel prize may be to buy one.

Search for Egypt's Nefertiti gains new momentum (Update)

September 29, 2015

The search for ancient Egypt's Queen Nefertiti in an alleged hidden chamber in King Tut's tomb gained new momentum as Egypt's Antiquities Minister said Tuesday he is now more convinced a queen's tomb may lay hidden behind ...


Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.