Dual Mobility Bearing Articulations Result in Lower Rates of Dislocation After Revision Total Hip Arthroplasty.

Introduction: The purpose of our study is to directly compare the rates of instability after revision total hip arthroplasty (THA) between a modular dual mobility (DM) and a conventional polyethylene single-bearing surface. Methods: We retrospectively reviewed a consecutive series of patients who underwent revision THA from 2012 to 2016 at a single institution with a minimum of 2 years of follow-up. Rates of re-revision, dislocation, complications, and short-form (SF-12) scores were compared between the DM and single-bearing groups. To control for confounding variables, a multivariate logistic regression analysis was performed. Results: Of the 267 revision THA patients, 94 patients had a DM bearing articulation (36%), whereas 173 patients (64%) had a conventional single-bearing with a mean follow-up of 37.8 months (range 24 to 73 months). The DM group was more likely to undergo revision THA for instability compared with the single-bearing group (8.5% versus 1.2%, P ≤ 0.005) but had reduced incidence of postoperative dislocations (2.1% versus 8.7%, P = 0.067) and no difference in the rates of re-revisions (9.6% versus 11.6%, P = 0.770). When controlling for confounding variables, patients who received a DM liner had lower rates of dislocation postoperatively than those of single-bearing (odds ratio 0.12, P = 0.019). Discussion: Even with a selection bias of surgeons using DM for patients at high risk of instability, patients undergoing revision THA with a DM bearing have reduced rates of dislocation at the intermediate-term follow-up. Further study is needed to identify any potential longer-term complications which may result from a modular DM bearing

The Blues: Religious or Anti-Religious?

This document was downloaded from the Rhodes College websiteBrian Darrith's paper explored the influence of religious themes on traditional and contemporary blues music. He did the research as a project in the Institute of Regional Studies.The Rhodes Institute for Regional Studies is made possible by the generous support of the Robert and Ruby Priddy Charitable Trust of Wichita Falls, Texas and the Mike Curb Family Foundation

The Blues: Religious or Anti-Religious?

This document was downloaded from the Rhodes College websiteBrian Darrith's paper explored the influence of religious themes on traditional and contemporary blues music. He did the research as a project in the Institute of Regional Studies.The Rhodes Institute for Regional Studies is made possible by the generous support of the Robert and Ruby Priddy Charitable Trust of Wichita Falls, Texas and the Mike Curb Family Foundation

Acetabular liner dissociation: A case report and review of the literature

Dissociation of the polyethylene liner from the acetabular shell is a rare but catastrophic complication of total hip arthroplasty (THA). There have been reports of polyethylene liner dissociation (PLD) as well as ceramic liner dissociation (CLD) in the literature. Amongst the commonly used implants, liner dissociation has been reported with the Pinnacle (DePuy), Harris–Galante (Zimmer) and Trident (Stryker) acetabular components. To the best of our knowledge, this is the first case report of PLD in an R3 (Smith & Nephew) acetabular component. This case report highlights the implant choice for treatment of the liner dissociation and the role of constrained implants in such cases

Comparison of Harris Hip Scores and Revision Rates in Metal-on-Metal Versus Non-Metal-on-Metal Total Hip Arthroplasty.

INTRODUCTION: This study compares functional outcome scores and revision rates between metal-on-metal (MoM) and non-MoM total hip arthroplasty patients. METHODS: A cohort of 75 patients who underwent implantation of the same dual modular hip arthroplasty between the years of 2004 and 2010 was enrolled. Patients were subsequently evaluated in 2015 to 2017 for joint revision history and functionality, as measured by the Harris hip score (HHS). Patients requiring a revision arthroplasty were not included in the HHS analysis. RESULTS: A total of 49 patients had MoM implants (65.3%), and 26 patients had non-MoM implants (34.8%). At a mean follow-up of 7.6 years, 10.2% (5/49) of MoM prostheses required revision, whereas 3.8% (1/26) of non-MoM prostheses required revision (P = 0.334). The mean HHS in the MoM cohort was 89.8, compared with 88.1 in the non-MoM cohort (P = 0.69). CONCLUSION: HHSs were not notably different between cohorts. The MoM cohort had three times as many revisions as the non-MoM cohort, but given the numbers available, this difference did not reach significance. Given the clinical importance of these revision data, further study is warranted to determine survivorship of the MoM versus non-MoM total hip arthroplasty at long-term follow-up

Comparison of Postoperative Instability and Acetabular Cup Positioning in Robotic Assisted versus Traditional Total Hip Arthroplasty

BACKGROUND: Robotic-assisted total hip arthroplasty (R-THA) affords precision yet uncertain clinical benefits. This study compares dislocation rates and related revisions between R-THA and manual total hip arthroplasty (M-THA). Secondarily we evaluated cup position, patient-reported outcome measures (PROMs), and postoperative complications. METHODS: A three-surgeon cohort study was conducted on 2,247 consecutive patients (1724 M-THA and 523 R-THA) who received a primary THA between January 2014 and June 2020 at a single hospital. Demographics, PROMs, emergency department visits, readmissions, and 90-day complications were collected via the Michigan Arthroplasty Registry Collaborative Quality Initiative. Chart review yielded instability occurrence with average follow-up of 4 years. Multivariate regression analysis was performed and a sample of 368 radiographs including all dislocations were assessed. RESULTS: There were significantly lower rates of dislocation in R-THA (0.6%) versus M-THA (2.5%; Multivariate odds ratio 3.74, p \u3c .046). All cases of unstable R-THA were successfully treated conservatively, whereas 46% of unstable M-THA were revised for recurrent instability. Cup anteversion (25.6° ± 5.4° R-THA vs. 20.6° ± 7.6° M-THA) was greater and cup inclination (42.5° ± 5.3° R-THA vs. 47.0° ± 6.7° M-THA) was lower in the R-THA group (p \u3c .05). No significant differences were noted for demographics, PROMs, or other complications (p \u3e .05). CONCLUSION: R-THA resulted in less than one-fourth the dislocation rate compared to M-THA and no revision for instability. It was associated with no difference in PROMs or other early complications. The influence of R-THA on stability goes beyond simply cup positioning and deserves further study