Update on sternal osteosynthesis.
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.