Scoliosis risk factors: age, sex and family history

What scoliosis is

Scoliosis is a sideways curve of the spine. Seen from behind, a typical spine looks straight; in children and teens with scoliosis it has an abnormal S-shaped or C-shaped curve, which can be on either side and in different places along the spine (NIAMS). In adolescent idiopathic scoliosis the bones of the spine are also slightly twisted or rotated (MedlinePlus Genetics).

Adolescent idiopathic scoliosis is the most common spinal abnormality in children and affects an estimated 2 to 3 percent of children in the U.S. (MedlinePlus Genetics). With treatment, observation and follow-up with the doctor, most children and teens have normal, active lives (NIAMS).

Who is more likely to get scoliosis

NIH says anyone can get scoliosis. The risk factors it names are (NIAMS):

• Age. Idiopathic scoliosis, the most common type, usually occurs in children age 11 and older. MedlinePlus says scoliosis is most common in late childhood and the early teens, when children grow fast (MedlinePlus).
• Sex. Girls are more likely than boys to have this type of scoliosis. MedlinePlus Genetics adds that mild curves are equally common in girls and boys, but severe and progressive curves occur more often in girls, for unknown reasons (MedlinePlus Genetics).
• Family history. You are more likely to have scoliosis if your parent, brother or sister has it. Adolescent idiopathic scoliosis can also occur in people with no family history of it (MedlinePlus Genetics).

What causes it

In most cases the cause is idiopathic, which means unknown. Researchers think a combination of factors, including genes, hormones and changes in cell structure, may lead to it (NIAMS). Many genes are suspected, but few clear and consistent genetic links have been found (MedlinePlus Genetics).

For some children, another condition or an injury causes the curve. NIH lists (NIAMS):

• Congenital factors, when the spine develops with a curve before birth.
• Genetic diseases.
• Injury to the spine, usually from trauma to the spine or back.
• Neuromuscular diseases, which affect the nerves that send messages to muscles and lead to muscle weakness and loss.
• A tumor that changes the shape of the spine.

Signs to look for

Sometimes the child, teen or a family member notices a change in posture. NIH lists these signs (NIAMS):

• The tops of the shoulders are uneven.
• One shoulder blade sticks out more than the other.
• One hip looks higher than the other.
• One side of the rib cage is higher than the other when bending forward.

MedlinePlus adds leaning to one side, and notes that scoliosis is sometimes easy to notice but not always (MedlinePlus). If the curve gets worse and becomes more severe, it can lead to back pain, and rarely a severe curve causes difficulty breathing (NIAMS).

Diagnosis

Doctors diagnose scoliosis with a medical and family history, a physical exam that looks at posture and at the trunk, shoulders and rib cage as the child bends forward, and x-rays, the most common test, which measure the curve (NIAMS). Some children are first identified through school screening (NIAMS). For what national guidance says about screening teens who have no symptoms, see our scoliosis screening check.

Treatment

Treatment depends on where the curve is, how severe it is, whether it causes symptoms and whether the child is still growing (NIAMS). Options NIH describes (NIAMS):

• Observation for a mild curve in a child who is still growing, which may mean visits with the doctor every few months.
• Bracing for a moderate curve while the child is still growing, to slow or stop the curve from increasing. NIH says research shows braces work well if the child is still growing and wears the brace as directed.
• Surgery if the child is still growing and the curve keeps progressing, such as spinal fusion or an expandable rod. All surgeries have risks; talk to the surgeon about the risks and benefits.
• Physical therapy to help strengthen muscles.

NIH notes that exercise programs have not been well studied but may keep scoliosis from getting worse, and that regular exercise helps children stay fit (NIAMS).

Common questions

Can scoliosis be prevented?

NIH does not describe a way to prevent idiopathic scoliosis, because in most children the cause is unknown (NIAMS). Knowing the risk factors and the signs can help it be found and followed early.

If I have scoliosis, will my child get it?

Not necessarily, but having a parent, brother or sister with scoliosis makes a child more likely to have it (NIAMS) (MedlinePlus Genetics).

Does mild scoliosis cause pain?

Usually not. Most children and teens with mild scoliosis do not have symptoms or pain (NIAMS), and mild scoliosis generally does not cause problems with movement or breathing (MedlinePlus Genetics).