Update on sternal osteosynthesis.

Abstract

Interfragmental compression enables primary bone formation in the bone fracture line and results in better and faster contact bone healing. The Controlled Tension Osteosynthesis System is a simple and uniform sternal closure method that makes use of the principles of widely used modern osteosynthesis techniques. A review of tensile tests of currently available sternal closure methods has shown that the wire closure is the weak link in all procedures. An anchor plate has been developed as a more efficient means of wire closure. In contrast to the most commonly used wire twist closure, which has an optimum strength that is only 20% to 33% of the original wire tensile strength, the anchor plate closure retains up to 80% of the wire's tensile strength. Used in combination with a steel alloy wire with a metallurgically increased tensile strength, it results in a sevenfold to ninefold increase in effective fixation stability. A specially designed instrument, the Strainsqueezer, enables easy clinical application of the anchor plate under controlled, standard conditions. The system offers an optimal compression osteosynthesis fixation using a minimal amount of foreign body material (thin, prestressed wire). Its development was based on technical experience gained through 6 years of clinical practice involving 800 sternotomies.