What is a sacral dimple?
A sacral dimple is a small dip or pit in the skin at the base of the spine, just above the crease of the bottom. It is present from birth and is very common: a few babies in every hundred have one. The vast majority are harmless and have no connection to the spine underneath.
Does a sacral dimple mean spina bifida or a tethered cord?
Almost never. A simple sacral dimple is very rarely linked to any problem. Occasionally a dimple sits over a hidden condition such as a tethered spinal cord or a closed (occult) form of spinal dysraphism, which is why some dimples are checked. The scan shows whether the spinal cord ends at a normal level and moves freely, which answers the question.
Which sacral dimples need a scan?
Simple dimples, small, within about 2.5cm of the bottom and with nothing else around them, usually need no scan at all. A scan is usually advised when a dimple is:
- Larger than about 5mm, or deep with no visible base
- Higher up the back, more than about 2.5cm above the bottom
- Accompanied by a tuft of hair, birthmark, skin tag, swelling or a crooked bottom crease
- One of more than one dimple
Why might my baby need a spine ultrasound?
Most often because a sacral dimple, hair tuft, birthmark or skin mark over the lower spine was noticed at the newborn check, or a doctor wants to rule out a tethered cord. Some parents book because a question was raised on an antenatal scan, or simply for peace of mind.
When should a baby spine scan be done?
Ideally in the first three months of life. At this age the bones at the back of the spine have not yet hardened, so ultrasound can see the spinal cord clearly. After around three to four months the window gradually closes, and MRI becomes the better test. If your baby is older, call us and we will advise.
How does a baby spine ultrasound work?
Your baby lies on their tummy while a small probe moves gently along the lower back. The specialist looks at the level where the spinal cord ends, watches it move with each heartbeat to check it is not tethered, and examines the tissue under any dimple to see whether it is skin-deep or connects deeper.
Is a baby spine ultrasound safe?
Yes. Ultrasound uses sound waves, not radiation, and needs no injection and no sedation. It is the recommended first test for babies precisely because it is so gentle, and it can be repeated safely if follow-up is ever needed.
Do sacral dimples go away?
A dimple does not usually disappear, but it often becomes less noticeable as your baby grows and the surrounding tissue fills out. A simple dimple that has been checked needs no treatment and causes no problems later in life; keeping it clean during nappy changes is all that is needed.
Is a sacral dimple genetic?
Sacral dimples can run in families, and many parents find that a relative has one. A family link does not make a dimple more worrying; what matters is how the dimple looks and whether it has any of the features that suggest a scan.
How long does a baby spine scan take?
The scan itself usually takes ten to fifteen minutes. Allow around half an hour for the appointment, so there is time to settle your baby and talk through the results.
What does the scan look at?
In the early months, ultrasound sees the infant spine directly:
- The level where the spinal cord ends, normally at or above the second lumbar vertebra
- Whether the cord moves freely
- The filum, the thin band at the end of the cord
- What lies beneath any dimple or mark
What happens if something is found?
If the scan suggests the cord is low, tethered, or that a dimple connects deeper, your specialist explains exactly what was seen and what it may mean. An MRI and a referral to a paediatric neurosurgeon or neurologist are arranged promptly, with the report and images in hand, so you are not starting from the beginning.
How much does a private baby spine ultrasound cost?
At Harley Street Ultrasound a private baby spine ultrasound costs £350, all fees inclusive: the scan, the specialist’s time and your written report. Same-day or next-day appointments are usually available, with the results explained before you leave.
Can a sacral dimple get infected?
A simple dimple rarely causes any trouble. If it ever becomes red, swollen, leaks fluid or smells, or your baby has a fever, see your GP promptly, because a dimple that leaks can occasionally indicate a small tract under the skin, which a scan can assess.
What if you find something?
Your specialist tells you in the room, in plain English, and explains exactly what it means. You will never be sent home to wait for a letter. Most findings are benign and need nothing more than a sensible review date.
Anything that does need attention gets a clear, objective recommendation in your report: monitor, test further, or refer. Follow-up tests can usually be arranged at 99 Harley Street, often the same week, and those results are also explained to you personally.
Do I need a referral?
No. Harley Street Ultrasound is a private clinic, so you can book a baby spine ultrasound in London directly online or by phone. No GP letter, no waiting list, and same-day or next-day appointments are usually available. If you are searching for a baby spine ultrasound near me from anywhere in central London, we are at 99 Harley Street, a short walk from Regent’s Park and Oxford Circus stations.
If you are wondering how much a private baby spine ultrasound costs, the answer is published before you book: £350, all fees inclusive: the examination, the specialist’s time, your written report and your images. Insured patients should bring a referral or authorisation number if their policy requires one.
How soon will I have the written report?
Usually the same day: a Harley Street baby spine ultrasound comes with same-day results as standard, and you will already know the findings, because they are explained to you on screen during the appointment.
The written report is prepared by the specialist team and published to your secure patient portal together with your images, with measurements and a clear recommendation, ready to share with your GP or specialist.
What happens after the scan?
Nothing special: there is no aftercare. Your child can feed, eat, play and go back to nursery or school straight away. Ultrasound uses sound waves, not radiation, so it can be repeated safely whenever follow-up is needed. If the results suggest a next step, your specialist explains it to you before you leave.
Can I still use the NHS afterwards?
Yes: completely. Coming to us privately never affects your NHS care. Our job is to get you answers quickly; if anything needs urgent attention, your specialist writes to your NHS GP recommending an urgent appointment, so you re-enter the NHS pathway with a diagnosis already in hand rather than joining the queue from the start.
