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Background: Sequential modifications to the manufacturing process of highly cross-linked polyethylene (HXLPE) have improved the wear resistance and implant survival of these liners in total hip arthroplasty (THA). However, no study has examined the long-term (mean 10 year) wear rates and clinical outcomes of third-generation HXLPE in THA. The aim of our study was to report the longest-to-date analysis of wear rates and clinical outcomes of a third-generation HXLPE liner., Methods: A series of 133 THAs using a specific HXLPE acetabular liner were retrospectively evaluated. Linear and volumetric wear rates were determined using a validated radiographic technique and clinical outcomes were analyzed. Multivariate analyses were performed to determine risk factors for accelerated wear., Results: At a mean follow-up of 10.4 years (range, 8 to 13.4), the mean linear wear rate was 0.0172 mm/year and the mean volumetric wear rate was 16.99 mm 3 /year. There were no instances of osteolysis or mechanical failures at any time point and there was a 100% acetabular component survival rate. Younger age and use of offset liners were independent risk factors for increased wear (P < .01 for both)., Conclusions: Our series of a third-generation HXLPE demonstrated very low wear rates and excellent implant survival at a mean of 10.4 years following primary THA. Future comparative studies at the 15- and 20-year follow-up timepoints are necessary to determine if such findings translate to true improvements in the tribological properties and longevity of these liners when compared to previous generations of HXLPE liners., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Background: Functional antibiotic hip spacers for treatment of periprosthetic joint infection may be retained in patients deemed too sick for reimplantation, or who elect to forego additional surgery. Our aim was to characterize reoperations, modes of failure, and function outcomes in patients who have retained hip spacers., Methods: We performed a retrospective review of 43 hips that underwent placement of an articulating hip spacer between January 1, 2014 and November 30, 2021. There were 28 hips that completed 2-stage exchange (TS group) and were reimplanted at mean 4 months (range, 2 to 10). The other 15 hips underwent planned spacer retention (RS group). Mean follow-up was 2.9 years (range, 1 to 6.1 years). The RS group was older (74 versus 66 years, P = .005) and had a higher age-adjusted Charlson Comorbidity Index (4.4 versus 3.3, P = .04) compared with the TS group., Results: Overall survivorship free of reinfection was 91% at 1 year and 86% at 5 years. There were 6 RS hips that underwent reimplantation for spacer failure at a mean of 23 months (range, 6 to 71 months) and 8 had radiographic stem loosening/subsidence. Patients who had a retained spacer at final follow-up were more likely to require a walker (P = .005) or wheelchair (P = .049) compared with patients who underwent reimplantation., Conclusions: Retained hip spacers can decrease overall surgical burden, but are associated with high rates of stem loosening, subsidence, and unplanned reoperation. Planned spacer retention should be undertaken with caution in patients healthy enough to undergo reimplantation., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Background: An increased rate of complications related to femoral component failure has been described with less invasive total hip arthroplasty (THA). This study evaluated the incidence of femoral complications associated with the direct anterior approach for THA., Methods: Retrospective review was performed of the initial 1120 consecutive patients who underwent direct anterior THA by 2 surgeons., Results: A total of 899 patients (80.3%) had a 2-year follow-up (range, 2-8 years). Complications within 90 days occurred in 20 patients (1.8%): 10 calcar fractures, 1 greater trochanter fracture, 1 canal perforation, 3 hematomas, 2 dislocations, 2 superficial, and 1 deep infection. Nine patients (1%) underwent revision: 5 for aseptic femoral loosening (0.55%), 1 for periprosthetic joint infection, 1 for dislocation, 1 for hip flexor irritation, and 1 for a damaged polyethylene liner. Of the 5 patients with aseptic femoral loosening, 3 had a short, mediolateral tapered stem, 1 cemented stem, and 1 S-ROM stem placed to bypass a canal perforation. There were no revisions for aseptic loosening in the collared, fully hydroxyapatite (HA)-coated compaction broached or triple tapered proximal fit and fill stem designs (70.6% of all stems). Revision rate for femoral loosening was significantly higher for tapered wedge over HA-coated, compaction broached stems (P < .005)., Conclusion: Pain and function improved predictably with a 0.55% rate of femoral loosening at 2-year follow-up. Among collared, fully HA-coated and triple taper fit and fill femoral stems, there were no instances of revision for aseptic loosening vs 3 in the short stem, collarless mediolateral tapered group., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Five matched pairs of fresh human femurs were used to quantitatively assess the structural integrity of the implanted Wright Medical Technology modular Infinity hip and the Osteonics single-piece Omnifit hip. The results showed that neither bone implant system was able to recreate the femoral anteversion of the intact femur (p < 0.05). Although the micromotion at the bone-implant interface was well within the limits of achieving bone ingrowth, the axial micromotion was greater for the Infinity hip than for the Omnifit hip (p < 0.05), but the rotational micromotion did not show a significant difference between the two bone implant systems (p > 0.5). The anterior proximal femur deformation patterns were similar for both the two bone implant systems and intact femurs. However, the medial proximal femur deformation patterns showed that the Infinity hip-implanted femur was more similar to the intact femur than the Osteonics Omnifit hip-implanted femur.