Experts agree that numerous factors can contribute to the onset of scoliosis. While some cases are classified as syndromic (secondary to a neuromuscular or neurological disease) or congenital (due to malformation or separation of the vertebrae), 80% of the cases are deemed idiopathic. A diagnosis of idiopathic scoliosis indicates that the spinal curvature occurs spontaneously with no known cause. Although the specific causes are unknown, scientific studies and history reveal that the condition tends to be familial, with a definite genetic component.
Idiopathic scoliosis is particularly well suited for genetic study since it is most frequently discovered in childhood. Due to these early diagnoses, scientists can study data from several members of a family over a sufficient period of time to gain insight into inheritance (Wise, 2008). Several of these studies indicate that there is a higher incidence of spinal curvature in relatives of a scoliosis patient than in the general population (Zeu, 2015). In fact, the Scoliosis Research Society reports that approximately 30% of Adolescent Idiopathic Scoliosis patients have some family history of the condition (Scoliosis Research Society, 2020).
Rose Bronstein is not at all surprised by these findings. She, along with her mother and her sister, has scoliosis. Although she and her mother were never treated, her sister had a curve that reached 50 degrees and required surgery when she was 16 years old. Today Bronstein’s two daughters, Mia (16) and Sydney (13), have both been diagnosed with scoliosis and are being treated at National Scoliosis Center.
“Scoliosis is very prominent in my family,” she says. “When Mia was five years old and we went to the pediatrician for the annual wellness visit, I had asked the doctor to check {her} for scoliosis. I was very clear about how prominent it was in my family.”
The pediatrician had Mia bend down and touch her toes then quickly declared, “She looks good to me.”
“I had the same request year after year and the doctor would report to me every year that Mia was fine. I trusted her. It wasn’t until I started to notice that Mia’s posture, stance, and musculature were off that a chiropractor suggested an X-ray. She was diagnosed right before age 12 with an S curve.”
Familial forms of idiopathic scoliosis were described as early as 1922, but recent studies of 1st-degree relatives, including those of twins, reveal even stronger evidence of genetic contributions to the condition. When studying concordance – the presence of the same traits in a set of individuals – geneticists found that there was a higher concordance among identical twins compared to fraternal twins. The study found that genetic factors are certainly involved in susceptibility to scoliosis. Some of the most exciting research, however, points to the genetic connection in particular aspects of curvature, especially curve severity (Wise, 2008). Doctors can use this information to predict curve shape, severity, and the potential risk for progression. Understanding research on these specific genetic correlations will greatly benefit families with a history of scoliosis.
Early detection is crucial to managing spinal curves and successfully avoiding invasive surgery. For this reason, families with knowledge of a family history are encouraged to be diligent in looking out for signs of the condition. In addition, seeking professionals properly trained in screening, monitoring, and diagnosing scoliosis will help to ensure options for non-operative treatments will be available.
“Until this day, my stomach hurts thinking about the pediatrician who was not listening to me stress how prominent scoliosis is in my family. Parents need to be proactive in monitoring their children at a very young age through imaging and a specialist,” urges Bronstein. “If I would have done both, I would have had Mia in a brace at age eight or nine and would have prevented the curve she has to manage and live with now. With Sydney, I was smarter and wiser and started to image her at nine years old.”
Scientists expect that future studies into the genetic factors involved in the onset of scoliosis will continue to validate current findings on familial forms of the condition. This promising research will enable families with a history of scoliosis to push for the earliest possible diagnosis for their children. In turn, doctors will be able to use this valuable information to help them make the least invasive treatment options available to their young patients.