The small, symmetrical indentations visible on the lower back, just above the buttocks, are a common, purely aesthetic feature of human anatomy. These markings appear directly over the sacroiliac joints, where the sacrum attaches to the pelvis. They are congenital, meaning they are present from birth, and are a normal variation in skin and skeletal structure. This article provides the proper terminology and anatomical context for these indentations.
The Anatomical and Common Names
The formal anatomical name for these paired indentations is Fossae Lumbales Laterales, which translates from Latin to “lateral lumbar indentations.” This term is used in medical anatomy to precisely identify the location of these surface markings.
The more commonly recognized, informal names are the “Dimples of Venus” for women and the “Dimples of Apollo” for men. These names stem from classical mythology, referencing Venus, the Roman goddess of beauty, and Apollo, the Greco-Roman god of male beauty.
The Underlying Cause in Anatomy
These indentations are not caused by muscle structure and cannot be created through exercise alone. Their formation is due to a specific structural tethering between the skin and an underlying bone structure. A short, fibrous ligament stretches from the skin directly to the posterior superior iliac spine (PSIS), a bony prominence on the back of the pelvis.
This ligament pulls the skin inward, creating the characteristic dimple where it attaches to the bone. The indentations are located directly over the two sacroiliac joints. Their visibility is influenced by the relative lack of muscle or subcutaneous fat in the immediate area, allowing the skin-to-bone connection to be noticeable.
Genetic Influence and Prevalence
The presence of these back dimples is considered a genetically inherited trait. While the exact genes responsible are not fully understood, the feature appears to be passed down through families. The inheritance pattern is likely polygenic, meaning multiple genes are involved in determining their development.
Although genetically predetermined, the visibility of the Fossae Lumbales Laterales can change throughout life. A low body fat percentage makes the dimples more apparent. Conversely, a higher body fat percentage can obscure them, even if the genetic predisposition is present. They are a common feature, often observed more frequently in women.
Clarifying Health Significance
The Fossae Lumbales Laterales are purely cosmetic features with no known negative health implications. They are benign, non-pathological, and do not indicate a deficiency or underlying medical condition. Their presence has not been correlated with issues like low back pain.
It is important to differentiate these aesthetic back dimples from a sacral dimple, which is a single indentation found much lower down, directly above the crease of the buttocks. While most sacral dimples are harmless, they can, in rare cases, be a sign of an underlying spinal issue, such as Spina Bifida Occulta. Aesthetic back dimples are always paired and located higher on the lower back. A sacral dimple is solitary and sometimes accompanied by other markers like a tuft of hair or skin tag, which would warrant a medical evaluation.