Early-Onset Scoliosis (EOS)

What it is

Early-onset scoliosis means a sideways curve of the spine found before a child's tenth birthday. The name describes when it starts, not why. Some curves have no known cause (idiopathic). Some come from bones that formed differently before birth (congenital). Some come from a nerve or muscle condition, and some are part of a syndrome. What these children share is a spine that still has most of its growing to do, and that changes everything about how we treat them.

In a teenager, a curve is mostly a problem of the spine. In a young child, it is also a problem of the chest. The spine is the back wall of the rib cage, and the rib cage is the home of the lungs. Most of the lung's air sacs form by about age 8, and the chest keeps growing in volume until the teen years. A short, twisted, or stiff chest can keep the lungs from reaching their full size. That is the reason early-onset scoliosis is treated differently and watched more closely than teen scoliosis: the aim is a chest that can grow, not just a straighter X-ray.

How it shows up

Parents often notice a tilt of the trunk, a shoulder or hip that sits higher, a rib hump when the child bends forward, or a crease in the skin on one side of the waist. In a baby, the pediatrician may notice the curve at a check-up. The child is usually comfortable. Pain, a curve that bends to the left in the chest, a fast change, or any weakness, numbness, or bladder change are not typical, and I look harder when I see them.

How we measure and follow it

On a standing (or sitting) X-ray I measure the curve in degrees, called the Cobb angle. In babies and toddlers I also measure how the ribs sit against the top of the curve. That measurement, called the rib-vertebra angle difference, is one of the best clues to whether an infant's curve will resolve on its own or keep growing.

Almost every child with early-onset scoliosis also gets an MRI of the whole spine. About one in five children with an early curve and no obvious cause has a difference in the spinal cord or the base of the brain that the X-ray cannot show. Finding it early changes the plan and keeps the child safe. The MRI is done under light sedation in young children. It is routine, not a sign that something is wrong.

I follow growth as closely as the curve. Height, weight, the stage of the bones in the hand and pelvis, and, in older children, signs of puberty all tell me how much growing is left and how fast the curve could change.

How we treat it

The plan depends on the child's age, the size and cause of the curve, and how much growth remains. Most of these treatments are meant to control the curve while the child grows, not to finish the job in one step.

• Watching: many small curves, especially in infants, stay small or get better. We recheck every few months.
• Serial casting: for curves that are growing in a young child, usually under age 5. A cast is placed on the body under a brief anesthetic, with gentle traction to stretch and untwist the spine. It is changed every 2 to 4 months as the child grows. In the youngest children with idiopathic curves, casting can sometimes correct the curve for good. In others, it delays surgery by years while the chest grows.
• Bracing: used after casting, or on its own for moderate curves in an older child. Braces cannot cure a curve, but they slow many of them down.
• Growth-friendly surgery: for larger curves that keep growing despite casting or bracing. Anchors are placed at the top and bottom of the curve and connected by rods that are lengthened as the child grows. Some rods are lengthened with a small operation about every six months. Magnetic rods can be lengthened in the office with an external magnet, without anesthesia, usually every few months. Other systems attach to the ribs or guide the spine as it grows.
• Halo-gravity traction: for very large or very stiff curves, a few weeks of gentle traction in the hospital before surgery can slowly straighten the spine and improve breathing.
• Final fusion: when the child is near the end of growth, the spine is usually fused for lasting stability. Some children who did well with growing rods do not need a separate final fusion.

What many families have not heard yet

• A curve in a baby can go away. Most infantile idiopathic curves under about 25 degrees with low rib measurements resolve without treatment. We watch rather than rush.
• Casting can be a cure, not just a holding pattern. Started early in the right child, serial casting can straighten the spine permanently. It is the only scoliosis treatment that can say that.
• Casting is a specialized skill. I trained in it at Shriners Children's Philadelphia, one of the centers where the technique was refined. Not every practice offers it.
• Lengthenings give less over time. Each lengthening of a growing rod gains a little less than the one before, because the spine gradually stiffens around the implants. That is one reason we delay the first surgery as long as it is safe to, using casts and braces to buy time.
• Growing-rod surgery is a journey, not an event. Over the years, most children with growing rods will need at least one unplanned trip back to the operating room, for a loose anchor, a broken rod, or an infection. I would rather tell you that at the start.
• Nutrition matters as much as the implant. Many young children with scoliosis are underweight. A child who is well nourished heals better, fights infection better, and tolerates surgery better. A dietitian is part of the team.
• A tether is sometimes an option. For an older child with early-onset scoliosis who is still growing, vertebral body tethering can guide the spine straighter without a fusion. It fits only some curves, and I will tell you honestly whether your child's is one.
• We measure what matters to your child. Beyond the X-ray, I ask about breathing, sleep, play, pain, and how your child feels about their body. A short questionnaire made for early-onset scoliosis helps us track that over the years.

The science: for the curious

The spine from the first chest vertebra to the pelvis grows about 2 centimeters a year in the first five years of life, slows to under 1 centimeter a year between 5 and 10, then speeds up again in puberty. A fusion stops growth across the fused segment, so fusing a young child's chest would leave it short for life. That is why we delay fusion and use methods that let the spine lengthen. The idea behind casting is that a growing spine can be guided by steady, gentle pressure: holding the curve corrected during growth lets the bones grow more evenly, and in the youngest children the correction can hold once the cast is off.

Learn more

Pediatric Orthopaedic Society of North America, Scoliosis: orthokids.org (opens in a new tab)

Scoliosis Research Society, Scoliosis (including early-onset): srs.org (opens in a new tab)

More for families

OrthoKids · POSNA

POSNA's OrthoKids: illustrated, family-friendly information on this condition.

Open on OrthoKids (opens in a new tab)

Scan for the OrthoKids page

This handout is general education and does not replace the personalized advice we discuss in clinic about your child's specific case. If anything here does not match what we talked about, what we talked about wins: please ask me.