The Dimples of Venus, often simply called back dimples, are a pair of shallow indentations situated on the lower back. These features are a relatively common anatomical variation that arises from a unique connection between the surface of the skin and the underlying bone structure. They are considered harmless and are not associated with any medical conditions, representing a natural part of human physical diversity.
Defining the Anatomy
The Dimples of Venus are located symmetrically on the lower back, positioned directly over the sacroiliac joints where the sacrum meets the ilium of the pelvis. These paired depressions are the result of a short, fibrous ligament that spans from the skin to a bony prominence known as the posterior superior iliac spine. This ligamentous connection pulls the skin inward, resulting in a visible indentation.
The anatomical term for these features is fossae lumbales laterales, or lateral lumbar indentations. Because there is no muscle tissue beneath them, their appearance cannot be altered through exercise, though changes in overall body fat percentage can make them more or less noticeable.
Prevalence and Genetic Influence
The prevalence of the Dimples of Venus varies among different populations, but they are a common feature. One study reported their occurrence in approximately 19.4% of the population, while another found them present in 41.9%, suggesting a wide range of visibility.
These indentations are frequently observed in women, which is how they received their name, but they also occur in men, where they are sometimes informally referred to as Dimples of Apollo.
The appearance of these back dimples is largely influenced by genetics, with evidence suggesting they follow a pattern of autosomal dominant inheritance. This means that a person only needs to inherit the gene from one parent for the trait to be physically expressed. While the specific gene is not definitively known, the trait often clusters within families, supporting the idea of a strong inherited component.
Medical Considerations for Sacral Dimples
It is important to distinguish the benign, bilateral Dimples of Venus from a different feature known as a sacral dimple. A sacral dimple is typically a single indentation located in the midline, just above the crease between the buttocks.
While most sacral dimples are also harmless, certain characteristics can occasionally signal an underlying issue with the lower spine or spinal cord. A physician may recommend an examination if a sacral dimple is deep, large, or accompanied by other skin abnormalities.
These concerning signs include the presence of a tuft of hair, a skin tag, or an area of discolored skin around the indentation. Such markers can sometimes be associated with occult spinal dysraphisms, such as spina bifida occulta or a tethered spinal cord.