Please select a country
- Česká republika
- CeramTec GmbH
- CeramTec-ETEC GmbH
- Emil Müller GmbH
The number of knee joint replacement operations performed each year is rising steadily. Experts estimate that around 2,000,000 knee replacements are implanted every year. As a result, knee replacement is the most frequently performed joint replacement, even taking precedence over hip replacement surgery.
The life expectancy of the of the world’s population is higher now than ever before: as such, the request for greater mobility and improved quality of life following knee replacement has also increased. The incidence of knee replacement in young and active patients is also increasing and therefore knee replacements must be able to offer longer implant lifetime.
In addition to this, infection, polyethylene wear, implant loosening and metal allergy are among the greatest problems in knee arthroplasty. Aseptic loosening is the predominant mechanism of failure and revision (31.2 %), followed by instability (18.7 %), infection (16.2 %), polyethylene wear (10.0 %), arthrofibrosis (6.9 %) and malalignment (6.6 %). 1 This is why the choice of implant material is so important, especially with respect to the wear properties and biological behavior of the selected materials.
“Periprosthetic joint infection (PJI) is one the most devastating complications of joint arthroplasty … the prevalence of PJI appears to be on the rise, with a projected number exceeding 60,000 to 70,000 hip and knee cases in the United States by 2023.” 3
The resulting increase of hip and knee revision is projected to exceed annual costs to US hospitals of infected revisions by USD 1.62 billion by 2020. 4 Although PJI is an infrequent complication (the reported incidence is 1 % - 2 % in the United States), it is the third most common indication for revision of primary total knee arthroplasty in the Medicare population.27, 28
Knee replacement implants are usually made from cobalt chromium alloy; titanium alloy is sometimes used for the tibial tray. An insert made of polyethylene is used as bearing articulating against the femoral component. Clinical evidence and long term results show that aseptic loosening limits implant lifetime. One of the most important causes of aseptic loosening is the wear of the polyethylene insert.7
As demonstrated in many investigations, an increased rate of polyethylene wear can lead to an increased rate of loosening as a result of the formation of granuloma and foreign-body reactions with associated destruction of bone stock. Ceramics have been shown to reduce polyethylene wear.
”The prevalence of metal sensitivity among patients with a well-functioning implant is approximately 25%, roughly twice that of the general population.”8
In vivo, metals release ions can cause biological reactions. The alloy used for articulating components typically contains metals such as cobalt, chromium and nickel. Several case reports and clinical studies report the clinical manifestations of metal allergy as eczema, disturbed wound healing, recurrent effusions, local swelling, persistent pain, osteolysis and reactions similar to pseudotumor with subsequent muscle destruction.8,9,16,17,18,19,20
In many cases sensitivity to these allergens has resulted in revision of the knee implants.
”In total knee arthroplasty, ceramics revealed superior experimental data concerning low wear rates as well as promising results of the first clinical applications.“15
”Ceramic implants are a promising solution for patients with allergies against metallic implant materials.“ 13
High-performance ceramics are biocompatible and bioinert.10 The ceramic material does not elicit any known allergic reactions. Case reports of hip and knee replacements have described significant improvement of symptoms and reduced levels of metal ions when revision is performed using ceramic components to address adverse reactions to components of metal implants.21,22,23,24,25,26
BIOLOX® ceramics are extremely stable and well tolerated by tissues.11,12 For this reason, ceramic components are now used also in knee arthroplasty.13,14 The extremely hard and smooth surface minimizes polyethylene wear.15
Studies have already suggested that ceramics could be superior with regard to delivering the lowest possible infection rates.5,29,30,31,32,33,34 These studies compared ceramics with metals and polymers. Analysis based on information from various hospital and national registers of 500,749 hip revisions, several of them implementing Cox multivariate analysis for confounding factors, has confirmed the potential of ceramics to reduce the risk of revision due to infection.6
The knee implants made of BIOLOX®delta are not FDA approved and are not available for commercial distribution in the United States.
*References available on file at CeramTec on request.
Please click on the button “Contacts” to the right, to get a list with the personal and direct responsible contacts within the CeramTec Group.
You are about to access the “Professional Information” area of the BIOLOX® website which is solely for Medical and Pharmaceutical Professionals. Please confirm that you are a member of this professional group.