Mechanical Implant Material Selection, Durability, Strength, and Stiffness

Living reference work entry


Spinal implants are manufactured from a variety of materials to meet user needs as well as the requirements of the physical and environmental demands upon the device. Commonly used materials include titanium, stainless steel, cobalt-chrome, nitinol, carbon fiber reinforced polymer (CFRP), polyetheretherketone (PEEK), silicon nitride, biodegradable polymers, and allograft bone. Material choices can be driven by requirements for strength, biocompatibility, bone ongrowth, flexibility, and radiolucency. Coatings may also be applied to the implants to further enhance physical or biological properties of the implant. These may include hydroxyapatite, titanium plasma, or a combination of these two materials. Additionally, implants may have a porous layer or open structure for improvement of osteointegration. Spinal implants are commonly made using conventional manufacturing methods such as machining and injection molding, but additive manufacturing is becoming more commonly used to produce certain implants.


Spinal Implant Titanium PEEK Cobalt-chrome Interbody Pedicle screw Cage Rod Hydroxyapatite 


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Authors and Affiliations

  1. 1.Research and DevelopmentDePuy Synthes SpineRaynhamUSA

Section editors and affiliations

  • Hassan Serhan
    • 1
  • Tony Tannoury
    • 2
  1. 1.Co-founder & TreasurerI.M.S. SocietyEastenUSA
  2. 2.Department of OrthopedicsBoston University Medical CenterBostonUSA

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