Is Robotic Arm Assisted Total Hip Arthroplasty More Bone Preserving than Conventional Hip Replacements and Hip Resurfacing?

Abstract

Background: Total hip arthroplasty (THA) is a common procedure that is increasingly being performed in younger patients. Deep acetabular reaming will result in more bone loss and the need for large acetabular components to be implanted. It can also lead to impingement, loosening, an altered center of rotation, and intraoperative periprosthetic fracture. The purpose of this study is to determine whether the single ream, robotic arm-assisted (RAA) THA can preserve a greater volume of bone stock compared to conventional hip replacement and resurfacing. Methods: We prospectively recruited 69 patients who had undergone primary THA using the Stryker Trident Acetabular System® in combination with the Stryker RAA System (MAKO)® and compared their mean reaming weight (g) with that of conventional hip replacement and resurfacing, as measured by Brennan et al. Comparison of acetabular reaming during hip resurfacing versus uncemented THA (J Orthop Surg. 2009; 17(1): 42-46). Results: The mean reaming weight using the MAKO system was 9.08 g, which was 29% less than the reaming weight using uncemented THA and hip resurfacing of 12.75 g. None of the acetabular cups required screw fixation. During the 35-month follow-up period, there were no complications related to cup placement or positioning. Conclusions: The use of RAA THA results in statistically significant preservation of acetabular bone compared to conventional hip replacement and resurfacing. This approach reflects the increased precision offered by RAA single reaming. Surgeons may consider utilizing RAA THA, particularly in younger patients, to better preserve bone stock as this could potentially impact future revision procedures.