FH Orthopedics

>> ATLAS is called ESOP Cup for the US market

The ATLAS acetabular cup is a cementless elastic acetabular cup. We have more than 20 years’ experience and more than 100,000 implants have been performed throughout the world, including in the USA.

The ATLAS acetabular cup comes in different versions of metal-back, with or without teeth, with or without screw holes, for a range that is sized in 2 mm increments, ranging from 40 to 74 mm so as to adapt to as many patients and indications as possible.


There is also a large range of inserts, made of polyethylene (UHMWPE), highly cross-linked polyethylene or alumina sandwich. The internal diameters of these inserts are 22.22, 28 and 32 mm for the flat-rimmed version, with a posterior or anti-dislocation wall.

Indications

The ATLAS elastic acetabular cup was designed for total hip arthroplasties, either as first intention or in cases of revision following loosening of the cup.

The concept

The principle of the ATLAS elastic acetabular cup was developed by Dr Dambreville more than twenty years ago.

The concept of the elasticity of the metal back was invented to counteract the risk of possible fracture of the cup during impaction.

The slit in this metal back closes during impaction, and only reopens when the insert is put into place. The result of this is the deformation of the metal back rather than of the bone acetabulum, as well as a distribution of forces over the entire surface of the metal-back during impaction of the insert, unlike forced impactions on rigid acetabular cups, where the press-fit is almost exclusively on the equatorial part of the cup.

Product characteristics

The ATLAS is made from a TA6V ELI titanium alloy and has a constant thickness of 2.5 mm. This makes it possible to obtain a maximum thickness of polyethylene (minimum 8 mm) to counteract the creep of the polyethylene.

The metal-back range is available in sizes 46 to 74 mm, in 2 mm increments, in the 3P version (with teeth and screw holes), 4P (with teeth but no screw holes) and the MS version (no teeth but with screw holes).
The various types of cup all have a hydroxyapatite coating for improved secondary fixation, and the MS version also has a T40 protuberance.
The polyethylene inserts are made of UHMWPE (Ultra High Molecular Weight PolyEthylene), and are available in diameters 22.22, 28 and 32 mm in a flat-rimmed version, with a posterior or anti-dislocation wall.
A range of highly cross-linked polyethylene inserts has also been developed. This range is called TRIANON and is available in 28 or 32 mm diameters (from size 50 mm).

Bibliography

SURVIVAL ANALYSIS AT 10 YEARS OF A COHORT OF 297 ATLAS TOTAL HIP PROSTHESES

European Journal of Orthopaedics Surgery and Traumatology
Volume 17. Number 6, November 2007 17:573-578
DOI 10.1007/s00590-007-0236-y

Marc AMEIL, Michel PHILIPPE

 

Abstract: the purpose of this work is to study the survival curve of ATLAS hip prostheses (acetabular insert) implanted by a single surgeon and with a minimum follow-up period of 10 years. Between January 1989 and December 1995, 297 ATLAS cups have been implanted at the Clinic St André in Reims, 171 ATLAS II non coated with hydroxyapatite and 126 ATLAS III which had a hydroxyapatite coating. Non-parametric survival curves have been calculated using the actuarial method. The survival rate of the global series of 297 cups ATLAS (coated or non-coated with hydroxyapatite) only considering the revisions in relation to the acetabulum (polyethylene wear, malpositions…) was of 90% at 10 years and of 85,5% at 15 years. It was more satisfactory for the ATLAS III cups with hydroxyapatite coating: 92,3% at 10 years and 88,4% at 14 years : which result confirms the merits of a surface treatment of the external wall. The revision rate for polyethylene wear was lower (3%). At a maximum follow–up time of 17 years, not any mobilization of the insert in the cup or any case of metallosis was reported.

ASSESSING THE STABILITY OF METAL BACK ACETABULAR INSERTS. A MICROSCOPIC STUDY OF EXPLANTS.

Eur J Orthop Surg Traumatol (2001) 11 : 213-218
ISSN 0948-4817

 A.DAMBREVILLE

 

Abstract: does microfretting occur between the insert and the shell of the metal back acetabular prostheses? Thirty explanted ATLAS inserts were studied under low power microscopy (x300) at the Laboratoire National d’Essai (LNE). Over the whole surface of the implant we noted the grooves left by machining. Any mobility between the insert and the shell should have destroyed these grooves which were several microns deep. There was no alteration in these machining grooves on any of the ATLAS explants even those with more than ten years follow up which dispels the hypothesis of the fretting on the convexity of the insert. This allows us to have confidence in the system of fixation between the insert and the shell. We, therefore, commend microscopic study of the explants to answer questions which clinical and radiological observation cannot answer.