Metallurgical and Mechanical Evaluation of 316L Stainless Steel Orthopaedic Cable

Stainless steel cable systems have been designed for a multitude of orthopaedic implant applications. Various implant fixation, cerclage, and tension banding techniques may be used with cable constructs to stabilize a variety of simple and complex bone fractures. Multifilament cable products, however, can pose special challenges regarding metallurgical evaluation and mechanical property testing. The present project investigated the metallurgical and mechanical properties of a new 316L stainless steel cable system designed for general trauma surgery. Important cable attributes such as strand configuration, cable construction, and finishing options are discussed. The advantages of inductively coupled plasma spectroscopy analysis are presented for the compositional verification of solid cable specimens. Metallographic methods for the examination of nonmetallic inclusion limits and grain size are described for a cable construct composed of 75 fine wires. The microstructure associated with laser remelted cable ends is documented via light microscopy. Unique tension test methods are described for the determination of failure load and elongation of 1.1 and 1.7 mm diameter cable sizes. Test results are compared with generalized requirements compiled in ASTM F 2180 Standard Specification for Metallic Implantable Strands and Cables.