Hip Resurfacing

Durom™ Hip Resurfacing - A Solution for Young and Active Patients

Product Information

Since 1988 MetasulTM has been successfully used for total hip replacement. Today’s metal on metal technology is the result of over one and a half decades of intense development, research and clinical evaluation. This has formed the foundation for the latest evolutionary development – Durom Hip Resurfacing .

Advanced engineering and materials technology coupled with Swiss precision manufacturing has resulted in this exceptional total hip prosthesis. Developed for the younger and more active patient, it is designed to provide high levels of joint stability whilst removing as little bone as possible. The articulating components are made of MetasulTM alloy ProtasulTM-21 WF, the first wrought-forged CoCr resurfacing prostheses, which is the same material used to restore mobility of over 200,000 patients.

Learning as Expressed in Design

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, but avoid the taper effect provide additional rotational stability.

Minimal Thickness - 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 the FDA requirements of 22 MPa.

Reduction of the Bearing Surface Roughness

The high carbon CoCr alloy is produced by a forging rather than 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.

Experience and Imagination Benefit the Patient

As with almost any joint replacement system, precise and easy-to-use instruments is the key to the successful restoration of the patient’s anatomy and function.

In developing of the DuromTM Hip Resurfacing the engineers not only focused on implant design and material technology. At the core was the surgical procedure, which had to address the specific needs and considerations of how to best resurface of the hip. As a result, an ingenious method to accurately and precisely position the components in the optimum position was created.

Not just Resurfacing The option of the large diameter MetasulTM ball head offers the advantage of a low wear solution whilst providing greater joint stability and high range of motion.   This facility is available in combination with the extensive range of cemented and un-cemented femoral implants from Europe’s largest manufacturer of joint prostheses. Confidence and choice – even if you have to revise a resurfacing femoral component!

Design Rationale Durom Hip Resurfacing has been designed for use in young active patients who are likely to outlive a "conventional" hip prosthesis. Emphasis has been placed on a high quality bearing surface, preservation of bone stock and durable fixation of the components to the skeleton.

Details

• The Metasul bearing is a proven low wear, low-friction articulation, having been implanted in over 200,000 patients since 1988. No other metal-on-metal bearing has such a track record.
  
  
• The Durom acetabular and femoral components have been designed to allow maximum preservation of bone stock. The wall thickness of the acetabular component is as low as practically possible and the cup subtends an angle of 165°, similar to the natural acetabulum. These features facilitate preservation of the acetabular bone stock. The sophisticated femoral instrumentation.
  
  
• Permits very accurate and reproducible positioning of the femoral component, allowing the smallest possible femoral implant to be used, which in turn allows the insertion of the smallest possible acetabular component, again preserving acetabular bone stock.
  
  
• The Porolock Ti VPS surface coating of the Durom acetabular component is vacuum plasma-sprayed pure titanium. This coating is associated with reliable bone in-growth ensuring long-term secondary fixation. The carefully controlled vacuum spraying process results in a very high adhesive strength between the chrome cobalt substrate and the Porolock Ti VPS coating, reducing the risk of the generation of titanium 3rd-body-wear particles.
  
  
• The femoral instruments produce an even cement mantle of approximately 1 mm, reducing the risk of fatigue failure of the bone cement. The recesses within the femoral component enhance rotational stability of the implant.
  
  
  
  

Indications for Hip Resurfacing

Hip resurfacing is most appropriate for physically active patients with good bone quality and adequate femoral and acetabular bone stock. Such patients will generally be under the age of 65.

• Primary Osteoarthritis
  
  
• Posttraumatic Osteoarthritis
  
  
• Secondary Osteoarthritis
  
  
• Avascular Necrosis of the Femoral head if remaining bone stock is Adequate
  
  
• Inflammatory Arthritis if bone quality is Adequate
  
  
• Patients with a deformity of the femur and/or internal fixation device that would make insertion of a stemmed femoral component difficult
  
  
• Patients with a High Risk of Dislocation

Contraindications for Hip Resurfacing

• Active Infection
  
  
• Malignant Tumours
  
  
• Insufficient acetabular or femoral bone stock
  
  
• Poor bone quality (e. g. osteoporosis, osteomalacia)
  
  
• Anticipated non-compliance of the patient, alcohol or drug abuse
  
  
• Decompensated renal insufficiency
  
  
• Known allergy to one of the constituents of the implant

Related Links

Surgery Prices

Why have Surgery in Belgium?

We can help with your Travel Arrangements

To Book please Contact Us by Phone, E-mail or Fax