Classic Marathon™

Standard Hip Stems

Special Hip Stem and Revision Stems

Material: Cold-worked QP-70 Stainless Steel to ISO 5832-9

CEMENT COMPRESSION POLY CUPS

CCOMMERCIAL IN CONFIDENCE
QP-70 ALLOY FOR CLASSIC MARATHON™

Since the very early 1960’s Austenitic stainless steel has been used in the manufacture of the hip stems.

This material was further re-defined in the search for stronger and more biocompatible grades of stainless steel.

This natural evolution lead to the introduction around 1977 /78 of the low carbon grade of stainless steel 316L.

Coincidentally, in mid 1970, a new grade of High Nitrogen 316 was being developed by a specialist steel company called Firth Brown Ltd., of Sheffield, UK, (REX 734) for use in the marine and gas turbine industry. This particular grade was soon recognised by some orthopaedic companies for its superior strength, corrosion resistance, stiffness and biocompatibility. In 1974 a patent for Rex 734 was granted to Firth Brown Ltd., which has since expired.

Around 1977, one of the leading UK orthopaedic companies called Thackray Medical, adopted this grade with minor modifications, as its primary grade of stainless steel.

In 1980, this grade of stainless steel (REX 734) lead to the establishment of the initial British Standard for surgical implants BS3531 pt. 2 comp.D. This specification was then superseded by BS7252 pt.9: 1990 and in 1992 was adopted by the International Standards Organisation for IS05832-9.

A number of leading implant manufacturers have used REX 734 as the basis for their in-house specifications e.g. *Depuy ORTRON9 0® and *Protec PROTOSULS 30®

In 1995, Implants International Ltd., adopted a similarly modified version REX 734 in its ‘cold worked’ state as the principal raw material for Classic Marathon™.

This material in its ‘cold worked’ state has superior fatigue strength to most other implant materials, when compared size for size. e.g.

There are a number of other important factors that also contribute to the long-term endurance of a stem.
These factors are.

• Design of stem
• Thickness and width of shaft
• Surface finish
• Neck geometry
• CCD angle or offset
• Effective instrumentation
• Cement Mantle Philosophy
• Proven Surgical Technique

The design of our Marathon system is based on the most successful cemented stem system with the longest proven clinical record. Our modular concept has been structured to provide surgeons with the flexibility of using either 22.225mm 0 or 28mm 0 femoral heads in QP-70 or aluminium oxide.

*Ortron 90® is a registered trade mark of Depuy/Johnson & Johnson.

*Protosul S30 ® Is a registered trade mark of Protec.