Magnesium and its alloys as orthopedic biomaterials: A review

doi:10.1016/j.biomaterials.2005.10.003

Biomaterials

Volume 27, Issue 9, March 2006, Pages 1728-1734

https://doi.org/10.1016/j.biomaterials.2005.10.003 Get rights and content

Abstract

As a lightweight metal with mechanical properties similar to natural bone, a natural ionic presence with significant functional roles in biological systems, and in vivo degradation via corrosion in the electrolytic environment of the body, magnesium-based implants have the potential to serve as biocompatible, osteoconductive, degradable implants for load-bearing applications. This review explores the properties, biological performance, challenges and future directions of magnesium-based biomaterials.

Section snippets

Introduction: the exciting potential of magnesium-based implants

Metallic materials continue to play an essential role as biomaterials to assist with the repair or replacement of bone tissue that has become diseased or damaged [1]. Metals are more suitable for load-bearing applications compared with ceramics or polymeric materials due to their combination of high mechanical strength and fracture toughness. Currently approved and commonly used metallic biomaterials include stainless steels, titanium and cobalt–chromium-based alloys. A limitation of these

Biological performance of existing magnesium-based orthopedic implants

Magnesium-based materials were first introduced as orthopedic biomaterials in the first half of the century. The first use of magnesium was reported by Lambotte in 1907, who utilized a plate of pure magnesium (actual purity level unknown) with gold-plated steel nails to secure a fracture involving the bones of the lower leg [33]. The attempt failed as the pure magnesium metal corroded too rapidly in vivo, disintegrating only 8 days after surgery and producing a large amount of gas beneath the

Suggested biological activity of magnesium metal

Osteoconductive bioactivity in magnesium-based metals is suggested by observations of increased bone apposition about magnesium-based implants compared to PLA controls [31] and a decreased time for hard callous formation when magnesium-based structures were used to support fractures in humans [34], [37]. While investigations of bone cell response to pure magnesium metal are scarce, a number of studies have investigated the effect of enriching the surface of a biomaterial such as hydroxyapatite

Alloying and surface treatments

The rapid corrosion rate of magnesium in the electrolytic physiological environment is one of the greatest limitations for its use in orthopedic applications. Unprotected magnesium exposed to a typical atmosphere will develop a gray oxide film of magnesium hydroxide (Mg(OH)₂) which slows corrosion [58]. These films of Mg(OH)₂ are slightly soluble in water, however severe corrosion occurs in aqueous physiological environments where chloride ions are present at levels on the order of 150 mmol/L,

Conclusions

While a substantial number of reports generate intrigue regarding the use of magnesium and its alloys as possibly osteoconductive, degradable orthopedic implants for load-bearing applications, a great deal of research is still necessary to appropriately evaluate magnesium's potential. As a first step, it is clear that modulation of the corrosion rate of magnesium-based materials in the physiological environment must be accomplished, possibly through the use of high purity magnesium or

Acknowledgements

One of the authors (MPS) would also like to acknowledge the Brian Mason Scientific & Technical Trust for their financial support.

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ReviewMagnesium and its alloys as orthopedic biomaterials: A review

Abstract

Section snippets

Introduction: the exciting potential of magnesium-based implants

Biological performance of existing magnesium-based orthopedic implants

Suggested biological activity of magnesium metal

Alloying and surface treatments

Conclusions

Acknowledgements

J Orthop Res

Biomaterials

Biomaterials

Biomaterials

J Orthop Res

J Shoulder Elbow Surg

Clin Chim Acta

Nutrition

Mol Aspects Med

Mol Aspects Med

Mutat Res/Fund Mol Mech Mutagen

Biomaterials

Biomaterials

Scripta Mater

SurfCoat Technol

Biomaterials

Biomaterials

Biomaterials

Mater Lett

Prog Mater Sci

Recent metallic materials for biomedical applications

Met Mater Trans A

Acute toxicity of metal ions in cultures of osteogenic cells derived from bone marrow stromal cells

J Appl Biomater

Corrosion of metal orthopaedic implants

J Bone Joint Surg

Metal release in patients who have had a primary total hip arthroplasty

J Bone Joint Surg

Metal degradation products: a cause for concern in metal-metal bearings?

Clin Orthop Relat Res

Variation in cytokines induced by particles from different prosthetic materials

Clin Orthop Relat Res

Titanium particles stimulate bone resorption by inducing differentiation of murine osteoclasts

J Biomed Mater Res

The effects of particulate cobalt, chromium and cobalt-chromium alloy on human osteoblast-like cells in vitro

J Bone Joint Surg

Metallic biomaterials

Materials and processes in manufacturing

Cellular solids. Structure and properties

Cellular solids. Structure and properties

Reinforcement of hydroxyapatite bioceramic by addition of Ni3Al and Al2O3

J Am Ceram Soc

Review
Magnesium and its alloys as orthopedic biomaterials: A review

Reinforcement of hydroxyapatite bioceramic by addition of Ni₃Al and Al₂O₃