Dr David McGrath

Spine Physician

MB BS (Hons) FAFOM, RACP, FAFMM
Master of Pain Medicine

Obtaining a comfortable sleep is very important for spinal health and recovery of injury.
The science of bedding is probably as rudimentry as the science of spines, however several principles, might have arisen.
1. Bedding should shape to the most comfortable spinal shape that is achievable
2. Once the bedding has conformed to a non painful spinal position,it should not creep over time.
3. Bedding should permit air circulation, to allow perspiration and normal thermoregulation.

These conditions are a tall order for any physical medium, and it is doubtful they have been achieved. Looking at each criteria.

Conformability
The bedding must shape conformably, to the reclining position, without allowing any sagging under gravity. The physics of gravity and the balance of forces means that each anatomical part is supported by the element of bedding directly beneath. It must do this, while at the same time exactly filling the shape of the spine as comfortably determined by the person. In other words,it must shape and support evenly, filling in all of the angulations. The bedding should be 100%deformable and yet provide 100% support. Like Goldilocks discovered, if the bed is soft, support tends to be insufficient. If the bed is supportive, it tends to be too hard. Finding the right balance, which is individual, is challenging.

Bedding Creep
If we can achieve a comfortable initial position,we have the potential problem of bedding creep. That is, the bed can become less supportive or moldable over the period of rest. As the bedding structures are under weight stress, they may move with time, to a less than satisfactory situation.This may not be a problem with a younger or more flexible person, but others may find they awake in discomfort. Typically people turn several times a night,probably,for this very reason.

Breathability
During the night we continue to perspire. If the water cannot escape, the skin becomes irritated and there is a threat to thermoregulation. We can become too hot and again awake in discomfort. Throwing off the blankets doesn't help, we are then exposed to cold air.

Given these three criteria,no wonder there are many different designs and materials.
Let's look at some options for mattresses.
1. Composite bedding with spiral springs, rubber foam, synthetic or natural fibre.
2. Synthetic rubber with holes
3. Other deformable synthetic materials such as Tempur-Pedic
4. Foam rubber and fiber covering only
5. The simple hammock
6. Water bed
7. Natural fibre fill such as futon

Requirements are likely to alter with age, and the onset of spinal disability. Generally oder people require more moldability and softness while painful joints need more support in the position of comfort, that is firmness. As injuries heal, bedding requirements may revert to the standard requirements.

With the present state of scientific knowledge, trial and error is still the best solution. Take note of comfort levels and quality of sleep in hotels beds, childrens beds,couches etc. In a show room,try to lie on the bed for a half hour or so.