One and a half decades of intense development, research and clinical evaluation in materials technology coupled with Swiss precision manufacturing has resulted in the emergence of Durom™ an exceptional Hip Resurfacing prosthesis.
Developed for the younger and more active patient, the Durom™ an exceptional Hip Resurfacing prosthesis is designed to provide high levels of joint stability whilst removing as little bone as possible. The articulating components are made of Metasul™ alloy ProtasulTM-21 WF, the first wrought-forged CoCr resurfacing prostheses, which is the same material used to restore the mobility of over 300,000 patients.
In designing the femoral component, many important factors needed to be considered. Bone conservation, precise positioning and an optimum cementing technique were of utmost importance. The guide pin, whilst removing less bone than comparable systems, allows for an ideal physiological transfer of load, whilst ensuring accurate positioning of the prostheses. The unique grooves, on the inner side, allow for even pressurisation of cement into the cancellous bone (a spongy type of bone with a very high surface area found at the ends of long bones), but avoids a taper effect, providing additional rotational stability.
Minimal Thickness with Maximum Strength
The acetabular cup is a flattened hemisphere, offering a greater range and freedom of movement. With a constant wall thickness of 4 mm throughout all sizes, the cup maintains an inner diameter as large as possible, whilst maintaining maximum implant strength and minimum bone resection. A coating of pure titanium, using a plasma spray under vacuum and static load is applied to the outer surface. This unique manufacturing method gives a surface roughness of 20–50 microns with a porosity of at least 25%, shown in vitro testing to significantly improve primary stability. As shown in laboratory tensile tests the adhesive strength of the titanium coating of 66.2–76.5 MPa, significantly exceeding FDA requirements of 22 MPa.
Lower Wear Rate
The high carbon CoCr alloy is produced by a forging rather than a casting process. This means that the size of block carbides is up to eight-times smaller compared to cast CoCr prostheses. The resulting lower surface roughness subsequently leads to a lower wear rate when compared with cast CoCr alloys. Co-28Cr-6 Mo-0,2C/ProtasulTM-21 WF (ISO 5832-12): a carbide-containing and therefore low-wear cobalt chrome alloy was chosen for MetasulTM.
The Key to Successful Resurfacing
As with almost any joint replacement system, precise and easy-to-use instruments are key to a success.
In developing of the Durom™ Hip Resurfacing the engineers not only focused on implant design and material technology but also concentrated on the surgical procedure, and how to resurface the hip in the best way possible. As a result, an ingenious method to accurately and precisely position components was created.
Low wear and greater joint stability
The large diameter of the Metasul™ ball head offers low wear coupled with greater joint stability and a high range of motion. This is available in combination with the extensive range of cemented and un-cemented femoral implants from Europe’s largest manufacturer of joint prostheses.