What is sacral dimple?

A sacral dimple is a congenital anomaly that presents as a hollow in the skin of the lower back, usually in the upper area of the crease that divides the buttocks. It is generally harmless and does not need to be treated.

However, sometimes sacral dimples can be related to a problem with the spinal cord or spine.

Types of Dimples

There are two types of sacral dimples:

• Conventional: These are located in the lower back near the crease that separates the buttocks and do not have any skin abnormalities. The risk of them being associated with spinal or spinal cord abnormalities is almost non-existent.
• Non-conventional: Their location varies, as they can be found in higher areas of the back or deviate to the sides, exhibiting skin abnormalities such as spots, bumps, hair tufts, or color changes. They have a higher probability of being related to vertebral or medullary anomalies such as:
  • Spina bifida occulta: Occurs when the spine does not develop completely during gestation.
  • Tethered spinal cord: In this condition, the spinal cord is trapped by abnormal tissues that limit its ability to move in the spinal canal.
  • Dermal sinus tract: This is an abnormal connection between the spine and the skin tissue, which is susceptible to causing infectious processes.

Signs of a Sacral Dimple

Sacral dimples present as depressions or indentations in the skin located in the lower back. In most cases, these dimples are a benign anatomical variation present from birth that does not cause symptoms and does not require treatment.

But sometimes, sacral dimples can be associated with underlying abnormalities in the spinal cord, as in the case of occult spinal dysraphism or a dermal sinus, especially if the dimple is deep, is well above the gluteal crease, or is accompanied by other skin signs such as a tuft of hair, a pigmented area, or discharge.

When a sacral dimple is related to a medical problem, certain warning signs may appear, such as swelling, redness, pus discharge, bad odor, or fever. This could be an indication of an infection, for example, a pilonidal cyst or a fistula.

In more severe cases, if there is associated neurological compromise, symptoms such as weakness in the legs, changes in sphincter control, or spinal deformities may be observed.

If any of these signs are present, it is important to seek consultation with a medical specialist, who may request studies such as an ultrasound or MRI, which will allow them to evaluate the internal anatomy and rule out other complications.

Although in most cases treatment is not required, there are some types of dimples that do need intervention.

Treatment will depend on the underlying cause. If the dimple is associated with an infected pilonidal sinus, discharge, inflammation, or signs of a fistula or cyst, medical evaluation is recommended. This can begin with conservative measures such as proper hygiene of the area, the use of antibiotics if there is a localized infection, or regular follow-up to rule out complications.

When the sacral dimple is related to a deeper congenital malformation, such as an abnormal connection to the spinal cord known as occult spinal dysraphism, or in case of suspicion of a fistulous tract that penetrates into internal structures, it may be necessary to perform imaging studies. If a structural abnormality is confirmed, the treatment is surgical to prevent neurological complications, recurrent infections, or abscesses.

For these cases, early intervention improves the prognosis and prevents long-term problems.

At the Pediatrics Center and in the Internal Medicine area at ABC Medical Center, we can provide you with specialized care. Contact us!