Implant Survival of 6,080 Tritanium Cups in Primary Total Hip Arthroplasty

Abstract

Background: To enhance osseointegration in total hip arthroplasty (THA), ultraporous or highly porous-coated cups were introduced. Implant survival data on these new devices have been scarce. The aim of our study was to assess the survivorship of ultraporous Tritanium cups (Stryker) in a population-based register study. Methods: In this study, we collected data on 6,080 primary THAs using a Tritanium cup and 25,670 THAs using a conventional cup (control group) from the Finnish Arthroplasty Register; these procedures were performed from January 1, 2009, to December 31, 2017. We calculated the Kaplan-Meier survival estimates with 95% confidence intervals (CIs). The end point was revision for any reason or for aseptic loosening of the cup. The revision risks were assessed with use of the Cox multiple regression model. The variables assessed in the Cox model were femoral head size, age group, involved side, operation year, sex, diagnosis, and fixation of the stem. The proportional hazards assumption of the Cox model was not fulfilled, so the follow-up time was divided into 3 time periods: 0 to 2 years, >2 to 4 years, and >4 years. Results: When comparing the 2 groups with regard to revision for any reason, the 5-year Kaplan-Meier survivorship of the Tritanium group (94.7% [95% CI, 94.0% to 95.4%]) was inferior to that of the control group (96.0% [95% CI, 95.7% to 96.3%]). In the Cox regression analysis of the 2 groups for the time period of >4 years, the Tritanium group had an increased risk of revision for any reason compared with the control group (hazard ratio [HR], 3.12 [95% CI, 1.82 to 5.35]; p < 0.001). With regard to revision for aseptic loosening of the cup, the Tritanium group had an increased risk of revision compared with the control group for both 0 to 2 years (HR, 3.80 [95% CI, 1.76 to 8.24]; p < 0.001) and >2 to 4 years (HR, 11.2 [95% CI, 3.28 to 38.0]; p < 0.001). Conclusions: There was no advantage to using the ultraporous-coated Tritanium cup for primary THA compared with conventional uncemented cups. However, wide CIs for some HR estimates may point to a lack of precision. Therefore, further research on subject is needed. Level of Evidence: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Higher risk of 2-year cup revision of ceramic-on-ceramic versus ceramic-on-polyethylene bearing: analysis of 33,454 primary press-fit total hip arthroplasties registered in the Dutch Arthroplasty Register (LROI)

“…Many studies have suggested that these factors can have an influence on a higher risk of overall revision, like a specific cup type, a lower age at the moment of surgery and female gender. [32][33][34][35] Although the higher incidence of revision in CoC was still significant after correction for these confounders in our study, it shows that the aetiology of early revision is multi-factorial. Focusing on aseptic loosening, in older patients, due to the reduced quality and density of the subchondral trabecular bone, in which the cup is inserted after reaming, there may be an increase in its elasticity.…”

Highly Porous Titanium Cups Frequently Presenting with Radiolucent Lines in Cementless Primary Total Hip Arthroplasty: A Retrospective Cohort Study

“…Comparing the two groups with regard to revision for any reason, the 5-year Kaplan–Meier survivorship of the Tritanium cup group (94.7%) was significantly inferior to that of the conventional titanium alloy cup group (96.0%). In the Cox regression analysis, there was an increased risk of revision for any reason in the Tritanium cup group compared with the conventional titanium alloy cup group at >4 years (hazard ratio, 3.12) [ 21 ].…”

Bisphosphonates’ use and risk of aseptic loosening following total hip arthroplasty: a systematic review

“…Acetabular screws favor primary stability and ensure better cup osseointegration (56), and trabecular metal acetabular cups benefit long-term osseointegration (57). Moreover, the implant coating type, porous covering extent, and the surgeon's expertise may also affect the AL risk (58,59,60,61). Additionally, numerous diseases such as diabetes mellitus, rheumatoid arthritis, sickle cell or Parkinson's disease (11,13,14,62), previous surgical operations such as spinal fusion or hip arthroscopy (63), and various drugs such as statins, beta-blockers and opioids have been implicated to the AL development (15, 16, 64).…”