ANTHOLOGY◊ Design and Technology
The ANTHOLOGY Primary Hip System offers more size options-14 different sizes, plus dual offset options for each size. Design innovations - such as reduced distal widths and an optimum neck geometry- allows you to more closely match the patient's anatomy for a better fit and better fixation.
ANTHOLOGY, is a bone conserving hip system that allows a precision fit in any type of femur and avoids premature distal locking of the stem. Its flat taper design and procedure-specific instrumentation help deliver exceptional patient fit.
Stem length and distal geometry
The length and distal width of many hip systems may prevent you from achieving the maximum metaphyseal fit while avoiding diaphyseal fixation. The ANTHOLOGY system was designed to grow in consistent 1.5mm increments and incorporates shorter stem lengths and slimmer distal widths in relation to the proximal widths. This design allows you to select a larger and more appropriate proximal size.
Anatomically correct neck lengths
Many competitive systems feature stems with comparatively long neck lengths. This length makes it difficult for you to choose proper stem sizes, make conservative neck resections and restore proper leg length. The ANTHOLOGY system incorporates consistent 131° neck angles, dual offsets and more appropriate neck lengths that have proven to ensure proper restoration of leg length and biomechanics in the vast majority of patients.* Also, the ANTHOLOGY system's constant 131o neck angle helps restore offset without affecting leg length. *Bourne RB, Rorabeck CH. Soft tissue balancing: the hip. J Arthroplasty.
2002 Jun; 17(4 Suppl 1):17-22.
POROUS PLUS◊ HA coating
POROUS PLUS HA coating uses ROUGHCOAT porous coating technology with an HA application.
ROUGHCOAT◊ porous coating
The sintered-bead ROUGHCOAT porous coating, manufactured from commercially pure titanium, has demonstrated several advantages over plasma-sprayed or simple textured surfaces:
- The irregularly layered beads of the ROUGHCOAT porous coating enhance the 3-D interlock of the prosthesis.
- Studies have shown stems with sintered beads result in two to three times less polyethelene wear in the acetabular component than stems with plasma sprayed surfaces. 1
- Sintered beads have been shown to have greater bond strength than plasma-sprayed surfaces or diffusion bonded wire surfaces. 2,3,4
- Mechanical testing has shown the optimal pore size for bone ingrowth to be between 50 and 400 microns. 1
A 50-micron thick layer of HA is applied to the ROUGHCOAT porous coating. A thinner HA layer can be discontinuous and cause a loss of mechanical integrity. Conversely, a thicker coating is likely to have lower attachment strength, leading to cracking and delamination under fatigue loads. The optimum thickness of HA has been shown to be 50 microns. 5
Want to learn more about the design features of ANTHOLOGY?
Click here to download the Design Rationale
1. Smith & Nephew Data. Bead pull-off testing of Ti-6AI-4V. In-House Test Data Summary. 1993 Feb.
2. Anderson P, Levine D. Adhesion of fiber metal coatings. ASTM STP 953: Quantitiative characterization and performance of porous implants for hard tissue applications, J Lemons, ed, ASTM Special Publication, 1987.
3. Robinson T, Bearcroft J. Smith & Nephew Advanced Technology Report. 1993 May.
4. Bobyn JD, Pilliar RM, Cameron HU, Weatherly GC, Kent GM. The effect of porous surface configuration on the tensile strength of fixation of implants by bone ingrowth. Clin Orthop Relat Res. 1980 Jun;(149):291-298.
5. Jaffe EL, Scott DF. Total hip arthroplasty with hydroxyapatite-coated prostheses. J Bone Joint Surg Am. 1996 Dec;78(12):1918-1934.
6. Søballe K. Hydroxyapatite ceramic coating for bone implant fixation. Acta Orthop Scand Suppl. 1993;255:1-58.