Hemispherical with Flattened Pole Dual-Mobility Acetabular Cup in Revision or Complex Hip Arthroplasty: Safety and Efficacy. The SYMCOR-2 study (NCT04209426)
Abstract
Gilles Estour, Nicolas Bonin, Schneider Loïc, Olivier Guyen and Frederic Daoud
Purpose: To Estimate the short-term clinical safety and efficacy of hemispherical with flattened pole chromium-cobalt metal back dual-mobility acetabular cups with porous outer coating and anchoring (HFPC-DMR-HA) or cement fixation (HFPCDM-CEM), in revision or complex THA.
Methods: Single-centre retrospective observational cohort study (title: SYMCOR-2, clinicaltrials.gov: NCT04209426) of consecutively operated patients who underwent THA with an HFPC-DMR-HA or HFPC-DM-CEM cup 2 years prior to study start. Prospective 2-year follow-up with letter and phone questionnaires.
Results: Sampling frame: 203 patients including 9.85% in the two cohorts with 15 HFPC-DMR-HA and 5 HFPC-DM-CEM. 30% lost to follow-up. Median follow-up (years): HFPC-DMR-HA: 2.3, HFPC-DM-CEM: 3.3.
Indications: HFPC-DMR-HA 67% revision & 33% primary THAs, HFPC-DM-CEM 100% revision.
Primary endpoint: 2-year implant survival rate: HFPC-DMR-HA 93% [59, 99], HFPC-DM-CEM 100%.
Prosthetic dislocation: HFPC-DMR-HA: 1 (6.7%), HFPC-DM-CEM: 0%. Secondary endpoint: Modified HHS (pain & functional sub score) improved with HFPC-DMR-HA from baseline 26.8 [14.9, 38.7] to 82.2 [73.5, 90.9] at 2-year follow-up (p<0.0001), HFPC-DM-CEM from 41.6 [24.9, 58.3] to 80.7 [55.8, 100].
Conclusions: The short-term benefit-risk balance was deemed satisfactory