Baby Physical Therapy: Flat Heads, Torticollis and Missed Milestones

Babies get referred for baby physical therapy for a short list of recognizable reasons: a head that always turns the same way, a flat spot developing on one side, a body that moves noticeably better on one side than the other, or motor milestones that are not arriving on time. Any of those is worth asking about, and none of them means something is seriously wrong.

What makes this age different is timing. In most areas of therapy, a few months either way changes little. In infant work it changes a great deal, and there is unusually clear evidence for that. Our pediatric physical therapy team sees more babies for these reasons than for anything else.

Why timing matters more here than anywhere else

The clearest data comes from congenital muscular torticollis, the tight neck muscle that produces a persistent head turn preference. The American Physical Therapy Association’s clinical practice guideline, updated in 2024, sets out how outcomes change depending on when therapy starts.

According to the guideline’s summary of the evidence, 99 percent of infants who began treatment before one month of age achieved excellent outcomes, with an average treatment duration of 1.5 months. Starting between one and three months, 89 percent achieved excellent outcomes, taking an average of 5.9 months. Between three and six months, that fell to 62 percent over 7.2 months. Between six and twelve months, it fell to 19 percent over 8.9 months.

Read those numbers again, because they are doing something specific. It is not just that later treatment is less likely to work. It is that later treatment takes longer as well. A family who starts at three weeks is typically finished before a family who starts at four months has properly begun.

The same guideline recommends that clinicians check for neck, facial or cranial asymmetry within the first two days of birth, and refer as soon as asymmetry is noticed. That is a standard many babies never actually get checked against, which is why parents so often end up being the ones who spot it.

The reasons babies are referred

A head turn preference. Your baby looks to one side much more than the other, resists turning the other way, or feeds comfortably on one side only.

A flat spot. Flattening at the back or side of the head, often the same side the baby prefers to look toward. The two frequently travel together, because a head that rests in the same position takes pressure in the same place.

Asymmetry. One arm reaches more than the other, one side of the body seems to do more work, or your baby rolls in one direction only.

Milestones not arriving. Not rolling, not sitting, not bearing weight through the legs, or arriving at each stage noticeably later than expected.

Muscle tone that feels different. A baby who feels unusually floppy to hold, or unusually stiff and hard to position.

A history that raises the odds. Prematurity, a difficult birth position, multiples, or a NICU stay all increase the likelihood of one of the above.

What torticollis and a flat spot actually are

These two turn up together often enough that it is worth separating them.

Torticollis, in infants, usually means one of the muscles running down the side of the neck is tighter and shorter than its partner on the other side. The effect is a head that tilts toward the tight side and rotates away from it. Some babies have a palpable thickening in that muscle. Many do not, and the only visible sign is the preference itself.

It is common, it is treatable, and it is not caused by anything a parent did. The usual explanation is position in the womb or during birth, which is why it shows up more often after a breech presentation, a tight fit, or a multiple pregnancy.

A flat spot, or positional plagiocephaly, is what happens when a skull that is still soft rests in the same position for long stretches. It is a consequence of pressure and time rather than of anything structural, which is also why changing pressure and adding time upright is the first line of response.

The link between them is straightforward. A baby who prefers to look one way rests on the same part of the skull, and the flattening follows. Treat the neck early and the pressure redistributes on its own in most cases. Leave the neck and the flattening tends to entrench, because a flattened area is itself more comfortable to rest on, which reinforces the preference that caused it.

That circular quality is the reason the timing evidence above matters so much. Both problems get easier to solve the earlier you interrupt the loop.

Is my baby just behind?

Sometimes, yes. Babies do develop at genuinely different rates, and a healthy baby can arrive at a milestone weeks after a sibling did without anything being wrong.

The more useful question is not how late, but what shape. A baby who is a little behind across the board, and who is steadily adding skills, is in a different situation than a baby who is on track for everything except one thing. Asymmetry in particular is worth taking seriously, because the body should be doing roughly the same job on both sides. One arm that reaches and one that does not is a pattern, not a delay.

Direction matters too. A baby who is slowly gaining is different from one who has stalled, and both are different from one who has stopped doing something they used to do.

If you are unsure which of those describes your baby, that uncertainty is itself a good enough reason to ask.

What a baby physical therapy session actually looks like

Nothing like what most parents picture.

There is no equipment to speak of, no exercises in the adult sense, and very little that looks like treatment. A session is mostly a therapist on the floor with your baby, using play, positioning and handling to get particular movements to happen, and then teaching you to do the same thing.

You should expect to be doing most of it. A baby seen once a week spends under an hour with a therapist and the rest of the week with you, so the work that changes things happens in your ordinary routine: how you carry, which side you feed from, which way the crib faces, where the interesting things in the room are. Your therapist should send you home with a small number of specific things to change, not a list of twenty.

Sessions are not painful. Stretching is done within a range the baby tolerates, and a baby who is genuinely distressed is telling the therapist something useful.

For babies under three, therapy may also be available through Georgia’s publicly funded early intervention system, which has its own referral route and its own rules. Many families use it, and some use both.

What you can do today

None of this replaces an assessment, and all of it is reasonable regardless.

• Tummy time, little and often. Several short spells a day beat one long one. Your chest or your lap counts if the floor is unpopular.
• Alternate everything. Which arm you carry in, which end of the crib the head goes, which side you feed from. Babies orient toward whatever is interesting, so move the interesting thing.
• Give them the other side. If your baby always looks right, put yourself, the light and the toys on the left and let curiosity do the stretching.
• Watch the container time. Car seats, swings and bouncers all hold a head in one position. They are not the enemy, but hours add up.

When to ask

Ask if you notice a consistent head preference, a developing flat spot, a one sided pattern, or a milestone that has not arrived when you expected it. Ask sooner rather than later, because the numbers above are the strongest argument in this article and they all point the same way.

You do not need to have decided anything before you call. Parents often hold off because they are not sure the thing they noticed counts, or because someone has told them to give it another month. A month is a meaningful proportion of the window the evidence describes, and no therapist thinks less of a family for asking about something that turns out to be nothing.

The worst outcome of asking early is being told everything is fine, which is a good afternoon. If any of this sounds like your baby, tell us what you are seeing and we will help you work out whether they should be seen.

About this article. Written and reviewed by the clinical team at Joy Therapy and Learning Center, a pediatric therapy practice in Cumming, Georgia.

This article is general information and is not a diagnosis or medical advice about your child. If something here sounds familiar, speak to your pediatrician or ask us for an evaluation.