English to French Medical Medical: Instruments shoulder surgery (rotator cuffs)

This is a technical medical document on the Affinis inverse reverse shoulder system which is a technique used in the treatment of massive and irreparable rotator cuff defects.

The context sentence concerns surgical revisions after a failed prosthesis implant:

"As few features as possible should be changed, to enable a reproducible follow-up in comparison to the former generation.
All components need to be able to be revised by a safe surgical approach as well as appropriate application of force during revision. Therefore, for example, a *hard—hard coupling* glenosphere/baseplate by a cold-molded Morse taper fixation was excluded from the beginning."

I understand the meaning to be that the glenosphere and the baseplate should not be coupled together without a softer material in between them?

I am not sure of this and unsure how to translate it correctly "couplage dur-dur"??? I see no instances of this on internet and it sounds strange...

I would greatly appreciate the input of those who are experts in this field.