The prospects of biodegradable magnesium-based alloys in osteosynthesis

Abstract

In the analytical review of the literature the main stages of development of biodegradable magnesium alloys in surgery and traumatology were discussed. The analysis revealed the main problems: there is no way to control the speed of the biological resorption alloys, the effects of products of magnesium degradation on the tissues and the organism in general are not studied, there is no information on the characteristics of the regeneration of bone tissue when implanted magnesium implanted magnesium alloys Materials for osteosynthesis with metal clamps made of steel X18H9T are used in 25,0-52,2% of cases, the corrosion of fasteners reaches 18-21%. Corrosion of the metal clips leads to the increase of the concentration of iron, chromium, nickel and titanium in the surrounding tissue. Electrochemical processes in metallic implants occurs due to their structural and chemical inhomogeneous. The microstructure of stainless steel is presented by differently oriented grains. Therefore, the question remains relevant to finding biodegradable materials suitable for implants for osteosynthesis, which could be completely metabolized by the organism, without causing of the pathological effects on the surrounding tissue and the body. The property of magnesium metal dissolved in the tissues of a living organism is known since the 19th century. Payr suggested the use of magnesium metal needles for the treatment of angiomas, in order to achieve thrombosis surrounding the tumor. In 1937 Lambotte made a post in the French Surgical Academy on the application of the osteosynthesis of the shin bone clamps with alloy Dow-metal (magnesium - 92% Aluminum - 8% + traces of manganese), made in the form of loops and screws. In 1938, Earl D. Mc.Braid and published their positive experience with plates and screws made of material similar in composition to the Dow-metal for osteosynthesis of fractures of the arm and forearm bones. Magnesium alloys may be used as a material for various types of implants for osteosynthesis in traumatology and orthopedics. As the analysis of scientific papers over the past decade, the number of scientific articles devoted to the study of the properties of magnesium alloys and their effect on bone formation, as well as their use in osteosynthesis has grown significantly. Implants which are based on magnesium, may have several advantages over bioinert metal alloys, polymers, and bioceramics. They are not toxic, not carcinogenic, the mechanical properties of a structure close to the cortical bone, and may have osteoinductive and anti-bacterial action. Also, there is no need for a second surgical intervention. The main problems to be addressed, in our view, are as follows. 1. Need to examine the nature of -bone formation in the fracture in the presence of the implant based on magnesium alloy. 2. To examine the impact of products of magnesium degradation on the surrounding tissue and the body as a whole. 3. Loss of rigidity of the implant magnesium based alloy in the process of biodegradation.