What can I do?
You do not need to do anything about pits, dimples, or hair tufts other than to bring them to the attention of your paediatrician. The area should be kept clean with regular bathing. No special care is required for a normal pit, dimple, or tuff.
When does my doctor need to be involved?
If the base of the pit is visible when the surrounding skin is gently pulled aside, then the pit is shallow and you should not worry. If the base of the pit is not visible, or if there is a tuft of hair arising only from the pit – rather than a patch of hair generally distributed in the region of the lower back – then your doctor needs to be involved. You also need to contact your doctor if the area has a thick tuft of hair sprouting from a relatively small patch of skin, or if the irregularity is in the form of a skin tag, skin swelling, or an unusual mark.
If a pit or dimple looks red and irritated, swollen, or tender, then it could be infected. Clear or yellowish fluid draining from the pit may be the fluid normally surrounding the brain and spinal cord. White fluid may be pus, signalling an infection. Your doctor should see your baby if he has any of these problems.
Most pits, dimples, and tufts are at the base of the spine, just above (or even tucked within) the crease of the buttocks. When a pit is visible much higher on the back, a doctor should be involved. Your doctor should also evaluate the pit if it is off to one side (not in the midline) or if there are other skin abnormalities in the general area.
Finally, when a child has any other visible defects, especially along the midline of the body, bring them to the attention of your doctor. The midline of the body is the imaginary line that connects the belly button up to the nose, travels up and over the head to the middle of the back of the neck, and then goes down to the crease in the buttocks. This “line” separates right from left.
Structures on either side should be fairly symmetric, and structures along the line should be intact. Some examples of midline defects include cleft palate and hypospadias.
What tests need to be done, and what do the results mean?
Most sacral dimples, pits, or tufts are normal, so testing is usually not necessary. If a test is done, then an ultrasound is typically the first choice. The ultrasound is placed on the baby’s lower back so that a doctor can see whether or not the spinal canal and the skin are connected in any way. If the ultrasound is too difficult to interpret, or if the baby is older than 6 to 12 months, then an MRI may be done.
The ultrasound or MRI can help to show whether or not there is a direct connection between the skin along the lower back and the spinal column below. An MRI can also illustrate the structure of the spinal cord. A normal result shows no connection between the spinal column and any surrounding structures.
What are the treatments?
A child with a connection between a sacral pit, dimple, or tuft and the underlying spinal cord requires surgery. Eventually this connection can limit spinal cord growth, damaging the nerves of the cord. In some cases, it can also lead to infection of the spinal cord or the fluid surrounding the spinal cord (meningitis).
If the skin around the pit is infected, then antibiotics are usually necessary. These must be taken by mouth; they cannot be applied to the site of the pit. If there is a large amount of fluid or pus, then drainage may be required. If the spinal cord or the cord’s surrounding fluid becomes infected, then intravenous antibiotics will likely be needed.
What are the possible complications?
When the area looks red or irritated, it could be infected. Infection may just involve the skin, or it may involve the deeper tissues, including muscles, nerves, the fluid around the spinal cord, and the brain.
The area of the dimple – or a neighbouring area, for that matter – can become filled with fluid. At this stage it is called a pilonidal cyst and often requires drainage.
If the sacral pit or tuff reaches down to the spinal cord and involves those nerves, then bowel and bladder function can become impaired. The most common manifestation is urinary tract infection caused by inability to effectively drain the bladder due to poorly functioning nerves. The resulting stagnant urine in the bladder breeds infection. If nerves that go to the bowel are involved, then chronic constipation may also result.