Survival and radioclinical evaluation of the Optimys™ short stem at more than 6 years’ mean follow-up: A retrospective study of 108 cases

Abstract

IntroductionThe short stems developed in recent years offer an interesting alternative to standard long stems. The Optimys™ short stem has been widely studied, but not according to the National Institute for Health and Care Excellence (NICE) criteria. We therefore conducted a retrospective study of Optimys™ at a minimum 5years’ follow-up, to assess: (1) survival on NICE criteria, (2) complications, (3) functional results, and (4) subsidence, restoration of offset and bone remodeling. HypothesisOptimys™ shows survival comparable to that of other non-cemented standard and short stems, with a<0.5% per year revision rate or<2.5% at 5years on NICE criteria. Material and methodsA single-center retrospective study included 108 Optimys™ stems at a mean 76.5months’ follow-up (range: 60–112months). Clinical [Harris, Oxford-12 and forgotten hip (French version: SHO-12) scores] and radiologic data were collected pre- and postoperatively. Analysis focused on implant survival, complications, functional results and radiological results (restoration of offset, bone remodeling, subsidence and osseointegration) and risk factors for stem migration. ResultsAt a mean 76.5months’ follow-up (range: 60–112months), Optimys™ survival was 97.7% (95% CI: 0.945–1). Oxford and Harris scores improved significantly: respectively, 16.1 vs. 44.7 [Δ=28.598; 95% CI: 27.410–29.785 (p<0.001)] and 45.3 vs. 95 [Δ=49.662; 95% CI: 47.442–51.882 (p<0.001)]. Mean forgotten hip score (SHO-12) at last follow-up was 82.7±19.6 (range: 35.4–100.0). There was 1 case of aseptic revision at 11months for femoral osseointegration defect. Mean subsidence was 1.64mm (range: 0–20.63mm); no predisposing factors could be identified. Femoral offset increased by a mean 2.41±4.53mm (range: −10.10 to 14.70mm). ConclusionThe present study reports good survival for the Optimys™ stem, which meets NICE criteria. Radiologic and clinical results were encouraging, with a low rate of subsidence, comparable to other series, but with increased femoral offset. Level of evidenceIV; retrospective cohort study.