No Difference in Reoperations at 2 Years Between Ceramic-on-metal and Metal-on-metal THA: A Randomized Trial

Abstract

Background Hard-on-hard bearings for total hip arthroplasty continue to warrant analysis even though crosslinked polyethylene is performing very well. Ceramicon-metal (CoM) has low in vitro wear and did well in an early clinical trial. We report on a prospective, randomized, multicenter investigational device trial comparing CoM with metal-on-metal (MoM). Questions/purposes (1) Is there a difference in the number or type of revisions comparing CoM with MoM? (2) Are cobalt and chromium metal levels different for CoM and MoM THA? Methods Between

Chemistry‐driven structural alterations in short‐term retrieved ceramic‐on‐metal hip implants: Evidence for in vivo incompatibility between ceramic and metal counterparts

“…However, failures associated with MoM/CoM implants are not necessarily due to the bearing surface itself only, but other potential reasons such as implant loosening, taper junction failures, and infection may also play a critical role . In this study, no malposition of the cups was found since the metal liner was yet well fixed and stable in the acetabulum.…”

“…In a double‐blinded randomized study, Schouten et al compared chromium and cobalt release in patients treated with CoM ( n = 41) and MoM ( n = 36) bearings but found no differences, after 6 and 12 months. Such comment was also made by Engh et al in addition to a similar number or type of revisions comparing CoM with MoM THAs . In contrast, Hill et al reported the presence of radiolucent lines and higher than expected levels of metal ions in the blood from the study of a total of 287 CoM THAs, and Zeng et al claimed that the use of a CoM THA was clinically effective and metal ion levels were significantly elevated at midterm follow‐up .…”

“…However, while investigative studies are yet underway to assess the real extent of these potential benefits, only few published evidence by clinical reports are yet available and very little is known about the actual material response in CoM articulations when introduced in the human body . A recent review on 56 CoM hips implanted between 2008 and 2009 at a single hospital by a single surgeon showed a high early failure rate of 10.7% within a mean of 1.5 years because of femoral stem loosening caused by high frictional forces .…”

“…Correspondence to: N. Sugano; e-mail: n-sugano@umin.ac.jp However, while investigative studies are yet underway to assess the real extent of these potential benefits, only few published evidence by clinical reports are yet available and very little is known about the actual material response in CoM articulations when introduced in the human body. [18][19][20][21][22][23][24][25][26][27] A recent review on 56 CoM hips implanted between 2008 and 2009 at a single hospital by a single surgeon showed a high early failure rate of 10.7% within a mean of 1.5 years because of femoral stem loosening caused by high frictional forces. 22 In a double-blinded randomized study, Schouten et al 24 compared chromium and cobalt release in patients treated with CoM (n 5 41) and MoM (n 5 36) bearings but found no differences, after 6 and 12 months.…”

Clinical Results and Serum Metal Ion Concentrations following Ceramic-on-Metal Total Hip Arthroplasty at a Mean Follow-Up of 60 Months

“…Several in vitro analyses showed a lower risk of implant fracture, reduced wear, and metal debris, as well as squeaking phenomena compared to CoC and MoM bearings [2, 5–7, 9]. …”