Is there a link between bed firmness and spine deformations?

Question

When I was a child, I was diagnosed with spine deformations: scoliosis, kyphosis and lordosis. The scoliosis is the most pronounced one in my case.

The professionals (I don't remember if it was the doctor or the rehabilitator who led my medicinal gymnastics classes) told us that it is connected to the bed I sleep in, and advised that I start sleeping on a firm mattress. I don't know exactly if they suggested that a soft mattress causes the deformation to start, or if it only exacerbates it once it has started. And indeed, in my childhood, I was sleeping on an old metal-springs bed which was quite sagging.

The advice has an obvious logic to it, but in the meantime, I've learned that many of the obvious things in medicine just ain't so. And also that doctors are as likely to fall for urban legends as anybody else. So I would like to hear if anybody has found out that there is a connection between bed firmness and spine curvature/spine deformities. If yes, does it only matter in childhood, or also for adults?

Answer 1

We should clarify some terms here. Scoliosis is a deformation, but Lordosis and kyphosis are not. The latter two are normal structural parts of human spine.

Back to your question, we don´t know.

Altogether the pathogenesis of scoliosis is poorly established and mostly unknown.

In adolescent scoliosis, it seems that presence of scoliosis is mostly associated to genetic factors (Burwell et al.). 97% of patients presenting with adolescent scoliosis have a positive familial history (Dayer et al.).

A recent review article sums the current knowledge of the pathogenesis of scoliosis (Dayer et al.). The interactions in molecular level, brain, vestibular system and in structural biomechanics are extremely complex and authors conclude quite fairly: "Many factors are potentially involved in the pathogenesis of adolescent scoliosis, leading some authors to formulate a complex collective model from these different concepts."

As so there is not currently any explicit evidence which would state the harms of any static risk factors (sleeping) affecting to development of scoliosis. Partly due to this vagueness I think the debate regarding risk of scoliosis is prone to bias and emotional "truths" and wisdoms.

In a recent population level study, authors found that sleeping in hammock was inversely associated to scoliosis (Baroni et al.). Still, it's possible that this study failed to take into account the possibility that children with scoliosis might be less likely to sleep in a hammock because of possible back pain in the morning. Correlation (or inverse correlation) does not imply causation.