Many years on this problem has obtained a kind of philosophical cast. But these are the opinions that define the problem. However... We are the only one who prefers not to give such a notorious name to mattresses. In our opinion an orthopedic mattress shall be tailor-made with consideration of physiological features of a patient and... using the new technologies theoretically it is possible.
How can it be done? It is not that easy task!!! A patient applies to a orthopedist who knowing about the specific problem shall schematically reflect arrangement of areas of different elasticity of a mattress, what would enable to ease uncomfortable feelings during the sleep and make it maximally comfortable for you. A producer in his turn performs that order strictly adhering to the scheme or if technology will not make it possible to perform the order 1:1, then offers his own version. And then it is required to re-agree that with your physician. However, practically we have never faced with such schemes.
As of present time all the producers use spring boxes similar on their characteristics, the only difference relates to secrets on assembly of the mattress and extra waddings. Spring diameter, wire or complicated structures of the spring spiral have no bearing to "healing" properties of the mattress. Due to the stated characteristics they correct bearing capacity of the article and its elasticity. Famous coconut coir provides stiffness (elasticity).
All the rest soft wadding: foam plastic, latex, synthetic and natural fillers provide elasticity and additional characteristics of comfort.
All the producers’ recommendations on a mattress model are based on the following parameters of yours: weight, height and personal preferences.
It is you who shall make the conclusion. Can the mattress be called orthopedic mattress if they sell it in a large-scale.
P.S. What makes a mattress the orthopedic one is not the specific size of that mattress.