Inferior Survival of Hydroxyapatite versus Titanium-coated Cups at 15 Years

Abstract

Hydroxyapatite (HA) particles have long been suspected to disintegrate from implant surfaces, become entrapped in joint spaces of orthopaedic bearing couples, and start a cascade leading to progressive polyethylene (PE) wear, increased osteolysis, and aseptic loosening. We compared cup revision at 15 years' followup in a randomized group of patients with 26 cementless THA components with titanium (Ti) versus first-generation HA coating. We also assessed radiographic PE wear and osteolysis to the 12-year followup or end point revision at a minimum of 5 years (mean, 10.9 years; range, 5-12.6 years). Two Ti-coated cups (17%) and eight HA-coated cups (57%) were revised at 15 years' followup. Femoral head penetration rate was 0.46 mm/year (standard deviation, 0.26) with the HAcoated cups (n = 12) and 0.38 mm/year (standard deviation, 0.14) with the Ti-coated cups (n = 10); we observed a wide variance of linear wear with the HA-coated cups. We also observed a positive association between high wear rate and revision, and between a high volume of osteolysis and revision. Our findings suggest inferior survival of mediumthickness spray-dried HA-coated cups with individual cases of excessive PE wear and premature cup failure. These findings apply to first-generation modular cups and may not apply to other cup designs and new HA-coating technologies.

The Salto Total Ankle Arthroplasty: Survivorship and Analysis of Failures at 7 to 11 years

“…The titanium anchoring layer in the Salto prosthesis has satisfied the FDA criteria only since 2006. The role of hydroxyapatite has been debated [2,4,32,38,[43][44][45].…”

Acetabular Components in Total Hip Arthroplasty: Is There Evidence That Cementless Fixation Is Better?

“…A few Level-I studies [26][27][28][29][30] on this topic have been published, but the majority of the evaluated studies had a level of evidence of II or III, which reduced the strength of the evidence. Moreover, only seven of the included studies compared the long-term outcomes of cemented and cementless acetabular components, and the availability of matched data (to control for effects of important confounders that can influence survivorship of the acetabular component) was relatively limited.…”

Calcium orthophosphate deposits: Preparation, properties and biomedical applications

“…Furthermore, inflammatory tissue reaction cases were detected [868,869]. More to the point, there are reports of adverse events associated with these deposits, which may fragment, migrate and even cause increased polyethylene wear secondary to third body abrasive wear [861,[870][871][872]. Interestingly that the short-term inflammatory response against HA deposits on Ti was lower in comparison to the DCPD ones.…”