clinical results with the accis THE ABSENCE OF WEAR 
The metal surfaces of the ACCIS prosthesis are engineered with the ceramic Titanium-Niobium-Nitride (TiNbN). TiNbN is integrated into the metal surfaces by physical vapor deposition to minimize wear.
- failure of cup fixation in patients of the first trial at the Slotervaart Ziekenhuis Amsterdam, the Netherlands, gave the opportunity of examining the capsule and soft tissue from behind the cup in 15 patients: examination of the biopsies demonstrated the complete absence of any adverse reactions to metal particles: no signs of hyper-sensitivity, necrosis, pseudo-tumour formation and no signs of inflammation . Also during a clinical trial at the Morriston Hospital, Swansea, UK, no problems originating from the TiNbN ceramic coating have occurred.
all components revised for whatever reason, have been studied extensively by implantcast GmbH, the manufacturer of the prosthesis. No errors of manufacturing could be detected. The TiNbN coating remained intact and present around the full femoral head and inside of the acetabular component with the exception of a very small area at the dome of the cup in some cases, demonstrating the effect of running in.
Comment
Some wear does occur during the running in phase of any metal-on-metal prosthesis. Fluid-film lubrication cannot be achieved in all prostheses. In most prostheses there will be initial contact at the dome due to the diametrical clearance between head and cup. With the ACCIS prosthesis this running in wear is limited to the running-in period. However the presence of the coating around the whole femoral head and the almost complete inside of the cup guarantees that corrosion cannot occur.
K.J. Hamelynck MD PhD , september 2009
THE ABSENCE OF ANY INCREASE OF METAL IONS IN THE BLOOD OF THE PATIENTA clinical multi-centre follow-up study on 200 ACCIS® Resurfacing implants (Morriston Hospital, Swansea, UK: David J Woodnutt, MD, FRCS, FRCS (Orth); Neville Hall Hospital, Abergevanny, UK: Robin Rice, MD,BMBS,FRCS; Arthro Clinic Hamburg: Genio Bongaerts, MD) is performed.Blood samples of 60 patients are analysed before, immediately after surgery and at intervals of 3, 6, 12 and 24 monts after surgery
THE ABSENCE OF ANY INCREASE OF METAL IONS IN THE BLOOD OF THE PATIENT (continues) 
The results of this ongoing study are shown in the above figures . It compares the level of cobalt ions in patients who received an Accis resurfacing hip, to those who received a non coated resurfacing hip as published by Günther and Witzleb (21) Identical differences are seen for Chromium ions and published by Hamelynck (download here)
None of the patients at any moment after operation has shown any significant increase of cobalt and chrome ions in the blood and none of the blood ion levels has been above the normal limits for metal ions in the blood as described in the Hand book for environmental medicine (61)
.The conclusion is justified that corrosion of the articular surfaces of the metal components of the ACCIS® prosthesis by the process of surface engineering of the surfaces with the ceramic TiNbN, is completely inhibited.
Early clinical results were presented at various
meetings (60,64-66) .
The above mentioned study will be finished in the 4th quarter of 2009 and subsequently publishedCONCLUSIONS 
The components of the ACCIS® system for THA and RHA incorporate important advantages over other metal-on-metal hip prostheses with large femoral heads:
the primary fixation of the acetabular component is very reliable due to the tri-radial design, equatorial press fit and TPS coating.
ceramic engineering of the articular surfaces of the metal components causes a minimization of metal wear.
corrosion of the metal surfaces is prevented and reduced to the minimum.
There is no need to fear for increased levels of metal ions in the blood and the un-known consequences of this increase.
K.J. Hamelynck MD PhD , october 2009