Neurosurgeons have longed for a lumbar cage that is light enough to limit the load on a patient’s spine but also fuses well with surrounding lumbar vertebrae.
Conventional lumbar cages are made of titanium or polyether ether ketone, known as PEEK, which can put a heavy load on the spine. Although some implants have porous material added to their surfaces to help with fusion, bone doesn’t grow through PEEK or solid titanium.
Rather than look for a new material, engineers at Stryker Corp. decided to fundamentally change how the device is manufactured. The Kalamazoo, Mich.-based devicemaker concluded that 3-D-printing could yield a significantly more porous titanium lumbar cage. The product could be lighter and better imitate the porous nature of bone, encouraging spinal fusion.
Physicians have increasingly looked to 3-D printing for unique implants and surgical models, and some manufacturers are now using the method to mass produce medical devices and even drugs that are more precise, customizable and biocompatible than conventionally produced products.