This chapter “Biomaterials in Spine Surgery” discusses on its first part, the essential properties sought in materials for implanted devices, including biocompatibility, mechanical properties, imaging compatibility, bacterial adhesion, and osseointegration. Materials must be biocompatible, meaning they should not provoke adverse reactions in the body. Corrosion is a major concern, particularly for stainless steel and titanium implants, which can release allergenic ions. Biomaterials should have an elastic modulus similar to that of bone, as well as fatigue resistance and tensile strength. The design of the implants significantly influences their mechanical properties, and innovations such as polyaxial screws have been developed to enhance performance. Devices must be compatible with imaging techniques such as CT and MRI. Some materials can disrupt imaging more than others, which needs to be considered during selection. Bacterial adhesion and biofilms pose a risk for infections. Specific materials or coatings can reduce bacterial adhesion, such as bactericidal coatings. The osseointegration process is crucial for the stability of implants. Implants should facilitate bone growth without forming fibrous tissue. Methods such as coating and surface treatment are employed to enhance osseointegration. The second part outlines various biomaterials used in spinal surgery, categorized into metal alloys, polymeric materials, ceramics, their specific characteristics, and surface treatment. Stainless steel (SS) is widely used due to low cost and ductility. However, it has high corrosion rates and is magnetic, which complicates imaging. Cobalt chromium alloy (CoCr) offers high strength and corrosion resistance but can induce cytotoxicity and allergic reactions. Titanium alloy (Ti-6Al-4 V) is known for good biocompatibility and lower modulus closer to bone. However, it can be brittle when bent and has poor osseointegration. Nitinol features superelasticity and is biocompatible, but may release nickel ions. Tantalum exhibits excellent osseointegration and is noncorrodible, though too strong for site bending. PolyEtherEtherKetone (PEEK) is used in intervertebral cages, offers good radiolucency but has poor hydrophilicity and osseointegration properties. PolyEtherKetoneKetone (PEKK) offers better temperature stability and strength than PEEK. Ultra-high molecular weight polyethylene (UHMWPE) is commonly used for joint replacements but is hydrophobic and can cause inflammatory responses. Viscoelastic elastomers are designed for total disc arthroplasty but require long-term studies due to concerns over wear debris. PolyMethylMethAcrylate (PMMA) is used in vertebral augmentation but has issues with osseointegration and can cause bone resorption. Ceramic materials are biocompatible and often used in intervertebral cages. They support osseointegration but can be brittle. Surface treatments, such as osteoconductive coatings (e.g., hydroxyapatite), enhance osseointegration. Bactericidal coatings, using materials such as silver, aim to reduce infection rates but have limitations regarding ion release and duration of effectiveness. In conclusion, the choice of biomaterials in spinal surgery involves balancing mechanical properties, biocompatibility, and imaging compatibility while addressing issues such as corrosion, osseointegration, and infection prevention.

Biomaterials in Spine Surgery

章节
发表日期：

2025年

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Jérôme Tonetti,
Mehdi Boudissa

摘要

This chapter “Biomaterials in Spine Surgery” discusses on its first part, the essential properties sought in materials for implanted devices, including biocompatibility, mechanical properties, imaging compatibility, bacterial adhesion, and osseointegration. Materials must be biocompatible, meaning they should not provoke adverse reactions in the body. Corrosion is a major concern, particularly for stainless steel and titanium implants, which can release allergenic ions. Biomaterials should have an elastic modulus similar to that of bone, as well as fatigue resistance and tensile strength. The design of the implants significantly influences their mechanical properties, and innovations such as polyaxial screws have been developed to enhance performance. Devices must be compatible with imaging techniques such as CT and MRI. Some materials can disrupt imaging more than others, which needs to be considered during selection. Bacterial adhesion and biofilms pose a risk for infections. Specific materials or coatings can reduce bacterial adhesion, such as bactericidal coatings. The osseointegration process is crucial for the stability of implants. Implants should facilitate bone growth without forming fibrous tissue. Methods such as coating and surface treatment are employed to enhance osseointegration. The second part outlines various biomaterials used in spinal surgery, categorized into metal alloys, polymeric materials, ceramics, their specific characteristics, and surface treatment. Stainless steel (SS) is widely used due to low cost and ductility. However, it has high corrosion rates and is magnetic, which complicates imaging. Cobalt chromium alloy (CoCr) offers high strength and corrosion resistance but can induce cytotoxicity and allergic reactions. Titanium alloy (Ti-6Al-4 V) is known for good biocompatibility and lower modulus closer to bone. However, it can be brittle when bent and has poor osseointegration. Nitinol features superelasticity and is biocompatible, but may release nickel ions. Tantalum exhibits excellent osseointegration and is noncorrodible, though too strong for site bending. PolyEtherEtherKetone (PEEK) is used in intervertebral cages, offers good radiolucency but has poor hydrophilicity and osseointegration properties. PolyEtherKetoneKetone (PEKK) offers better temperature stability and strength than PEEK. Ultra-high molecular weight polyethylene (UHMWPE) is commonly used for joint replacements but is hydrophobic and can cause inflammatory responses. Viscoelastic elastomers are designed for total disc arthroplasty but require long-term studies due to concerns over wear debris. PolyMethylMethAcrylate (PMMA) is used in vertebral augmentation but has issues with osseointegration and can cause bone resorption. Ceramic materials are biocompatible and often used in intervertebral cages. They support osseointegration but can be brittle. Surface treatments, such as osteoconductive coatings (e.g., hydroxyapatite), enhance osseointegration. Bactericidal coatings, using materials such as silver, aim to reduce infection rates but have limitations regarding ion release and duration of effectiveness. In conclusion, the choice of biomaterials in spinal surgery involves balancing mechanical properties, biocompatibility, and imaging compatibility while addressing issues such as corrosion, osseointegration, and infection prevention.