10/08/2026
Low modulus does not mean low stiffness.
As surgeons rethink interbody cage selection, low modulus of elasticity has become the selling point. That's progress. But it's only half the story.
Modulus is a property of the material. Stiffness is a property of the device: the material plus how much of it there is and how it's shaped. Same material, different geometry, completely different behavior under load.
A cage can be marketed as "low modulus" and still be far stiffer than the endplate it sits on. Stiffness mismatch at the bone–implant interface has long been implicated in subsidence.
At SpinePoint (www.spinepointusa.com), we designed the Flex-Z®cage around both numbers: a low effective modulus from its porous titanium architecture and a device stiffness built to work with the endplate, not against it.
So next time a vendor tells you their cage's modulus, ask the second question: how stiff is the device?
Stiffness matters.
See you at NASS in San Antonio next week!
