Design Rationale and Early Clinical / Surgical Observations with a Short Curved Tissue Sparing Hip Implant “The Apex ARC™ Stem”
Architectural changes occurring in the proximal femur (resporption) after THA (due to stress shielding) continues to be a problem1,2,3,4,5,12. Proximal stress shielding occurs regardless of fixation method (cement, cementless). The resultant bone loss can lead to implant loosening and or breakage of the implant. We are seeing younger patients with higher levels of physical activity as compared to just a decade ago. This has brought back a renewed interest in hip resurfacing along with significant interest in minimally invasive surgical approaches and smaller profile implants.
Tissue sparing surgery in THA is credited to Prof. Pipino, from Monza, Italy who has been working on this concept for over 30 years6.The Apex ARC™ Stem is built off the pioneering work of Pipino, Freeman, Townley and Whiteside with new novel design features. In this paper, we review design rationale, surgical technique, clinical impressions, learning curves and lessons learned to-date. In particular, our first 650 stems have been implanted, with 500 being reviewed by the posted surgical team over the past 16 months.
Key Words: Total Hip Arthroplasty, tissue sparing, neck preserving, neck stabilize
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Copyright (c) 2014 Timothy McTighe, Dr. H.S. (hc), Declan Brazil, PhD
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