Safety and Efficacy of Hemispherical with Flattened Pole Dual-Mobility Acetabular Cup in Primary Hip Arthroplasty: the SYMCOR-1 Study

Abstract Background: This study estimated the short-term clinical safety and efficacy of hemispherical with flattened pole cobalt-chromium metal-back with porous outer hydroxyapatite coating dual-mobility acetabular cup (HFPC-DM-HA) in primary total hip arthroplasty.Methods: Single-center retrospective observational cohort study of consecutive patients undergoing total hip arthroplasty with a HFPC-DM-HA 2 years prior to study start. Prospective 2-year follow-up with letter and phone questionnaires.Results: Sampling frame: 361 patients including 59 patients (16.3%) in the cohort. 6 patients (10%) lost to follow-up. Median age 77.5 years (range: 67 ; 92), 32% female, median BMI 25.2 kg.m-2 (18.4 to 56.8). Clinical indications: Primary THA in all patients, resulting from primary osteoarthritis in 80% of them. Median follow-up 3.0 years (2.7 to 4.1). Primary endpoint: 2-year implant survival rate: 97% [87, 99]. Prosthetic dislocation: 0%. Secondary endpoint: Modified HHS (pain & functional subscore) improved from baseline 39.7 [34.6, 44.7] to 75.8 [72.1, 79.6] at 1-year and to 86.7 [83.7, 89.7] at 2-year follow-up (p<0.0001).Conclusions: The authors deemed the short-term outcomes of this acetabular cup in primary total hip arthroplasty to be satisfactory.Study registration: clinicaltrials.gov NCT04209374.