EXACTECH HIP Design Rationale
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Tapered Wedge Femoral Stem Surgeon focused. Patient driven.TM

The word “Alteon” is derived from the Latin word “altus” meaning “high,” denoting Exactech’s high performance, next-generation hip system. This system is designed to deliver a reproducible, efficient and predictable clinical experience. Introduction The Alteon® Tapered Wedge is a next-generation, single-taper, wedge-style stem. It incorporates specific philosophies, and is designed to improve surgical experiences and clinical outcomes. The Tapered Wedge collarless design intends to achieve immediate axial and rotational mechanical stability between the medial and lateral cortices of the...

FIRST GENERATION DePuy Tri-Lock SECOND GENERATION Biomet TaperLoc Biomet TaperLoc Complete (RDD) NEXT GENERATION EXACTECH ALTEON TAPERED WEDGE

Design History and Evolution of Wedge Stems Previous iterations of single-taper, wedge-style stems can changes to the stem and head prostheses emerged, generally be classified into first- and second-generation the transition from first- to second-generation stems designs. Traditional, first-generation, single-taper wedge occurred. This eventually led to design modifications stems are based off the cemented Mueller stem of the that included, but are not limited to: cut off or shorter 1970s. These stems initially featured proximally coated, overall prosthesis length, reduced distal geometry...

Unmet Clinical Needs DISTAL POTTING OF THE FEMORAL STEM In spite of historical implant success, several clinical challenges remained unaddressed with the second-generation implant designs. One of these challenges is proper medial/lateral fixation of the tapered wedge implant in femurs that have a substantially greater proximal/distal canal mismatch. Cooper et al. noted that risk factors associated with failure of osseointegration (of the implant) included a smaller canal-flare index, and a greater canal fill at the mid-and distal-thirds of the stem.10 This complication, where an implant...

PERIPROSTHETIC FRACTURES Studies have reported that periprosthetic fractures following primary total hip arthroplasty performed using a non-cemented tapered wedge stem design have increased since their first introduction. Cooper and Rodriguez suggest the increased incidence of periprosthetic fractures in first-generation, single-taper wedge stem designs (Accolade I) may be due to “the hand broached preparation technique necessary to achieve a tight press-fit for immediate component stability, or due to the wedge-shaped design of this (particular) implant. The incidence of ” these fractures...

Exactech Implant Design Philosophy for Tapered Wedge Since its founding in 1985, Exactech has operated with a primary goal of providing implants and services that seek to improve patient outcomes. The Tapered Wedge Surgeon Design team, Jeff Pierson, MD, (Franciscan St. Francis Health, Carmel, Indiana) and Micahel Kang, MD, (Insall Scott Kelly Institute, New York , New York), alongside our engineering team, set out with several design goals in mind to address the clinical challenges previously mentioned. DESIGN GOALS 1) The proximal/distal stem ratio should allow the implant 3) The stem...

Standard Base Neck Length INCREMENTAL SIZING In order to satisfy design goal number two, solving common kinematic issues without the was taken when designing the neck grouping scheme for the Tapered Wedge stem. Some first- and second-generation competitive designs feature base neck lengths that are too large, have too large of a jump between need for modular necks, careful consideration stem sizes, or require modularity in order to solve kinematic issues during the surgical The Tapered Wedge stem has four base neck Alteon Tapered Wedge length groups. The system was intentionally...

In order to achieve immediate axial and rotational stability of the implant, several geometric features were designed into the implant. The proximal/distal transitional geometry resulted in a lateral flare feature which is designed to evenly distribute loads in the proximal femur and provide initial mechanical stability (see image below).14 Low profile lateral shoulder allows for ease of insertion when implanting the stem. The Alteon Tapered Wedge features a highly polished neck cross-section that is minimized on the medial aspect to increase range of motion, decreasing the chance of...

PLATFORM INSTRUMENTATION The Tapered Wedge is part of the Alteon family of hip stems. This platform hip system features a set of common femoral instruments that can be used across multiple stems. Alteon Common Femoral Instruments (Upper Level Tray) Alteon Common Femoral Instruments (Lower Level Tray) Alteon Tapered Wedge Instruments – Anterior Approach or all other approaches BROACH DESIGN • The system uses rasping-style broaches. • hen the Tapered Wedge prostheses is impacted to an W axial stopping point, the proximal border of the TPS will be approximately 1.5mm above the final broach. •...

GLOBAL HEADQUARTERS References 1. Healy W, Tilzey J, Lorio R, Specht L, Sharma S. Prospective, Randomized Comparison of CobaltChrome and Titanium Trilock Femoral Stems. J Arthroplasty. 2009;24:831-6. 6. hite C, Carsen S, Rasuli K, Feibel R, Kim P, W Beaulé P. High Incidence of Migration with Poor Initial Fixation of the Accolade® Stem. Clin Orthop Relat Res. 2012 Feb;470(2):410-7. 11. acobs C, Christensen C. Progressive subsidence J of a tapered, proximally coated femoral stem in total hip arthroplasty. Int Orthop. 2009 Aug;33(4):917-22. 2. urt C, Garvin K, Otterberg E, Jardon O. A Femoral...