Implant Breakage Risk for Modular Fluted Tapered Stems in Revision Total Hip Arthroplasty at 5-Year Follow-Up

Abstract

Background: Modular stems in revision total hip arthroplasties allow diaphyseal fixation and optimal restoration of the architecture of the proximal femur. Several studies report metaphyseal implant breakage in the mid- to long-term and therefore a huge impact on survivorship. We aimed to evaluate a specific design of uncemented modular fluted tapered stems (MFT) to analyze survivorship and clinical and radiological outcomes.Methods: In a retrospective study, we identified 99 patients who had surgery using the same design of MFT implant between 2012 and 2014. Patients were mainly male in 53% and mean age was 73 years. Indications were 33 aseptic loosening, 24 periprosthetic fractures, 23 periprosthetic joint infection, 1 instability and 18 were complex primary arthroplasties. Survivorship, complications and clinical outcomes, were assessed. Mean follow-up was 5 years.Results: There was no implant breakage. At 5-year follow-up, the survivorship free of revision for aseptic loosening and free of revision for any reason of the femoral stem were 100% and 99%, respectively. At last follow-up, they were 94% and 81%, respectively. Six implants were revised. A mean stem subsidence of 6 mm was noted in 9 cases; 1 was revised for aseptic loosening. The Harris hip score was 89. The risk of revision was significantly higher for shorter diaphyseal implants (p=0.026).Conclusion: At mid-term follow-up of 5 years, the MFT studied reported an excellent survivorship and clinical outcomes with no specific complications. Unlike literature reports, no specific complications occurred with this design. Satisfying clinical outcomes and limited subsidence are consistent with previous reports though.Level of evidence: IV – Case series

Revision total hip arthroplasty using a fluted, tapered, modular stem follow-up method for a mean of three years: A preliminary study

“…Postoperative micro-motion and fatigue stress of the junction may lead to breakage between the distal and proximal parts of the prosthesis, failure of the locking mechanism, and dislodging of the proximate sleeve ( Cross and Paprosky, 2013 ; Stimac et al, 2014 ). Lucena et al (2020) reported that at a 5-year follow-up, there were no implant breakages and the survivorship was 100% free of the need for revision for aseptic loosening and 99% free of the need for revision for any reason concerning the femoral stem ( Lucena et al, 2020 ). Sivananthan et al (2017) reported no complications regarding modular junctions.…”