Wear Performance Evaluation of a Contemporary Dual Mobility Hip Bearing Using Multiple Hip Simulator Testing Conditions

Clinical Outcomes, Survivorship and Adverse Events With Mobile-Bearings Versus Fixed-Bearings in Hip Arthroplasty—A Prospective Comparative Cohort Study of 143 ADM Versus 130 Trident Cups at 2 to 6-Year Follow-Up

“…In addition no indirect pattern of wear, including the classic scalloping of the calcar, was ever demonstrated through the entire study. Our wear performances of the "modern" dual mobility cup analyzed in the present study are in accordance with a recent study by Loving et al [29] describing the testing results of a dual mobility hip under non-ideal conditions: abrasive, induced impingement conditions, as well as immobilization of the insert at either of the two articulations using a hip joint simulator. It is often assumed that the additional articulation in the dual mobility concept would lead to higher wear than that of a single articulating design, but the results reported in this joint simulator study are to the contrary and would strengthen the findings of the current study and would be confirmed at best later on by RSA studies [30].…”

“…The second published "classic" cause of failures was intraprosthetic dislocation [7]. The ADM cup used in this study may prevent these intra-prosthetic dislocations, thanks to prevention of wear with the newly manufactured annealed highly crossed polyethylenes (HXLPE) which are nowadays available to be used with it [29]. Recent studies over 10 years on fixed HLXPE bearings have clinically confirmed, even in young patients, excellent long term results previously demonstrated on Hip simulators and RSA studies [35] as well as in clinical reports at 10 years minimum follow-up [36].…”

The dual mobility liner: Is it ready for prime time?

“…One study simulated scenarios of impingement, abrasion and loss of one of the dual articulations [12], the other, the effects of microseparation and third body particles [13]. Findings of these studies showed lower wear rates than single articulating THA's, likely due to shear stress reduction at the polyethylene interface.…”

Wear of dual-mobility cups: a review article

“…Such complication was widely reported with the first-generation of DM bearings [7,8] but notably reduced-up to 0%-with newer-generation designs and adoption of smoother and thinner necks [9][10][11][12]. Moreover, the advent of highly cross-linked PE (HXLPE) seems to have improved this issue, as both in vitro tests [13,14] and early clinical data have shown encouraging results in comparison with conventional PE [15][16][17].…”

“…Loving et al [13] measured wear of HXLPE inserts in a hip simulator under the aggressive conditions of immobilised liner, impingement and abrasion. Wear rates were smaller than those with single articulation for each testing condition.…”