Article entitled ¿bicortical contact predicts subsidence of modular tapered stems in revision total hip arthroplasty" written by peter moriarty, md, gerard a.Sheridan, md, frcs, liana wong, md, shane guerin, md, frcs, rehan gul, md, frcs, james a.Harty, md, frcs published by the journal of arthroplasty 26 march 2020 was reviewed.The articles purpose was to describe the intraoperative parameters that affect stem subsidence rates in tapered modular femoral stems for revision total hip arthroplasty (tha).The purpose was also to determine the effect of the stem bicortical contact on subsidence rates and whether there is a minimum threshold bicortical contact that must be achieved to avoid the complication of subsidence.This was a retrospective cohort study consisting of 109 hips in 105 patients (53 males and 52 females) at a minimum of 2 years of follow-up.All revisions were carried out for paprosky type 3a and 3b femoral deficits.Clinical outcomes included the indication for revision, aseptic re-revision surgery, specifications of the stem inserted, and specifications of the femoral head and acetabular components implanted.Radiographic outcome measures included subsidence (mm) and bicortical contact (mm).The results of the study included: using multivariate regression analysis, 3 parameters were associated with an increased rate of stem subsidence.A reduced bicortical contact distance (p <.001) and a stem length of 155 mm (p <.001) were both associated with higher subsidence rates.We also demonstrated a novel threshold of 20- mm bicortical contact which must be achieved to significantly reduce subsidence rates in these modular femoral stems for revision tha.Conclusion: subsidence rates of modular tapered femoral stems for revision tha can be significantly reduced by increasing the initial bicortical contact of the stem within the diaphysis and the overall length of the femoral stem >155 mm.We describe a minimum threshold bicortical contact distance of 20 mm that should ideally be exceeded to significantly reduce the risk of stem subsidence within the femoral canal.This study involved stems implanted during a revision surgery.There were 6 revisions for infection, 73 for loosening, 30 for periprosthetic fracture.There was no information provided as to what manufacturer of implants were implanted during the primary surgery, so it is unknown which components may have been depuy prior to this studies beginning.For this study, there were depuy stems noted and competitor stems noted.It was noted that 12 patients after the start of the study underwent a revision surgery, but no details provided as to the manufacturer of the implants revised were or the specific reasons for revision.General adverse events noted in this study that included depuy components included: subsidence, leg length discrepancy, femoral stem loosening.Specific adverse events for depuy products included a revision for instability x4, and 1 periprosthetic fracture.It was noted that 12 patient (unknown manufacturer) underwent re-revision arthroplasty procedure, specifics were not provided with this statement.For the purpose of this review, it is known that the patient had a reclaim stem, it will be assumed that the femoral head was a depuy product as well.
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Product complaint # (b)(4).Investigation summary: no device associated with this report was received for examination.All available x-rays were reviewed, and no evidence of implant fracture, disassociation, or anything indicative of a device nonconformance was found.Depuy synthes considers the investigation closed at this time.Should additional information be received, the information will be reviewed, and the investigation may be re-opened as necessary. device history lot: the product investigation found no evidence suspecting an error in the manufacturing or material that would be a contributing factor in the reported allegation(s).A manufacturing records evaluation (mre) was not performed.
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