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11.
《The Journal of arthroplasty》2022,37(8):1636-1639
BackgroundThe use of personal-protection surgical helmet/hood systems is now a part of the standard surgical attire during arthroplasty in North America. There are no protocols for the disinfection of these helmets.MethodsThis is a prospective, single-center, observational study. Helmets worn by 44 members of the surgical team and foreheads of 44 corresponding surgical personnel were swabbed at three distinct time points. In addition, 16 helmets were treated with hypochlorite spray to determine if pathogens could be eliminated. Swabs obtained were processed for culture and next-generation sequencing (NGS).ResultsOf the 132 helmet samples, 97 (73%) yielded bacteria on culture and 94 (71%) had evidence of bacterial–deoxyribonucleic acid (DNA) on NGS. Of the swabs sent for bacterial identification at the three time points, at least one from each helmet was positive for a pathogen(s). Of the 132 forehead samples, 124 (93%) yielded bacteria on culture and 103 (78%) had evidence of bacterial-DNA on NGS. The most commonly identified organism from helmets was Cutibacterium acnes (86/132) on NGS and Staphylococcus epidermidis (47/132) on culture. The most commonly identified organism from the foreheads of surgical personnel was Cutibacterium acnes (100/132) on NGS and Staphylococcus epidermidis (70/132) on culture. Sanitization of helmets was totally effective; no swabs taken the following morning for culture and NGS identified any bacteria.ConclusionThis study demonstrates that surgical helmets worn during orthopedic procedures are contaminated with common pathogens that can potentially cause surgical site infections. The findings of this study should at the minimum compel us to develop protocols for the disinfection of these helmets.  相似文献   
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BackgroundThe goal of this study is to investigate the migration and inducible displacement of a bicruciate-stabilized (BCS) total knee arthroplasty implanted using gap balancing (GB) or measured resection (MR) surgical techniques. We hypothesized equal migration and displacement between the techniques.MethodsThe study is a single-blinded, prospective, randomized controlled trial, with allocation of 71 patients to either GB or MR groups. Fifteen patients were withdrawn, resulting in 31 patients in the GB group and 25 in the MR group. Patients received the JOURNEY II? BCS implant. Migration and inducible displacement were evaluated using radiostereometric analysis and patient examinations were performed at a 2-week baseline, and at 6 weeks, 3 months, 6 months, 1 year, and 2 years postoperation.ResultsNo differences (P > .05) existed between GB and MR groups for any measurement of tibial or femoral migration. Both groups had tibial migrations below 0.5 mm from baseline to 6 months, and below 0.2 mm from both 6 months to 1 year and 1-2 years postoperation. No differences (P > .05) were found between GB and MR groups for inducible displacement.ConclusionNo differences were found in implant migration or inducible displacement between GB and MR groups. The BCS implant can be expected to have migration risks on par with industry standards and both surgical techniques are safe and effective options for implantation of this implant design.  相似文献   
14.
《The Journal of arthroplasty》2022,37(10):2090-2096
BackgroundIt remains unclear whether reimplantation of a patellar component during a two-stage revision for periprosthetic total knee arthroplasty infection (PJI) affects patient reported outcome measures (PROMs) or implant survivorship. The purpose of this study was to evaluate whether patellar resurfacing during reimplantation confers a functional benefit or increases implant survivorship after two-stage treatment for PJI.MethodsTwo-stage revisions for knee PJI performed by three surgeons at a single tertiary care center were reviewed retrospectively. All original patellar components and cement were removed during resection and the patella was resurfaced whenever feasible during reimplantation. PROMs, implant survivorship, and radiographic measurements (patellar tilt and displacement) were compared between knees reimplanted with a patellar component versus those without a patellar component.ResultsA total of 103 patients met the inclusion criteria. Forty-three patients (41.7%) underwent reimplantation with, and 60 patients (58.3%) without a patellar component. At a mean follow-up of 33.5 months, there were no significant differences in patient demographics or PROMs between groups (P ≥ .156). No significant differences were found in the estimated Kaplan-Meier all-cause, aseptic, or septic survivorship between groups (P ≥ .342) at a maximum of 75 months follow-up. There was no significant difference in the change (pre-resection to post-reimplant) of patellar tilt (P = .504) or displacement (P = .097) between the groups.ConclusionPatellar resurfacing during knee reimplantation does not appear to meaningfully impact postoperative PROMs or survivorship. Given the risk of potential extensor mechanism complications with patellar resurfacing, surgeons may choose to leave the patella without an implant during total knee reimplantation and expect similar clinical outcomes.Level of EvidenceLevel III.  相似文献   
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BackgroundMetabolic syndrome (MetS) is related to the increased risk of major cardiovascular diseases (CVD). The link between high serum total bilirubin (TBL) is cross-sectionally related to MetS and its components. However, whether serum TBL predicts incidence of MetS and its components remains inconclusive.MethodsThe present study included 893 women aged 70 ± 9 years from a rural village. We examined the relationship between serum TBL and MetS based on the modified criteria of the National Cholesterol Education Program's Adult Treatment Panel (NCEP-ATP) III report in a cross-sectional (N = 893) and cohort (N = 288) data.ResultsIn the cross-sectional study, serum TBL (β = 0.536, p < 0.001) as well as age, alcohol consumption, exercise habits, history of CVD, SUA, GGT, and ALT was significantly and dependently associated with number of MetS components, but in the cohort study serum TBL was not associated with number of MetS components. Compared with the 1st tertile of serum TBL (0.20–0.55 mg/dL), multivariate-adjusted odds ratio (95% confidence interval) for the 2nd -3rd tertiles of serum TBL (0.54–2.00 mg/dL) was 0.70 (0.51–0.95) in the cross-sectional study and 0.41 (0.21–0.81) in the cohort study.ConclusionsOur data demonstrated an independently negative association between serum TBL and MetS in Japanese community-dwelling women.  相似文献   
17.
《The Journal of arthroplasty》2020,35(7):1885-1890
BackgroundThe aim of this study is to evaluate midterm clinical and radiographic results of total hip arthroplasties (THAs) with cementless implants for adult patients with sequelae from childhood hip infection.MethodsBetween 2002 and 2016, 165 patients (165 hips) who had a hip infection during childhood were treated with THAs with cementless implants. The average duration of follow-up was 93.5 months (range 26-206). Clinical results were evaluated via the Harris Hip Score and radiographic results were analyzed with postoperative serial X-rays.ResultsThe average Harris Hip Score increased from 27 (range 8-53) before surgery to 91 (range 45-100) at the latest follow-up examination (P < .001). At the latest follow-up evaluation, 9 cementless acetabular components demonstrated partial, nonprogressive radiolucencies. No subsidence of more than 2 mm or evidence of a radiolucent line was observed around the femoral components. Intraoperative periprosthetic fractures occurred in 11 hips, including 3 acetabular fractures, 2 fractures of greater trochanter, 1 femoral shaft fracture, and 5 fractures of femoral calcar. Postoperative complications included 3 cases of periprosthetic infection, 1 episode of dislocation, 1 case of a femoral periprosthetic fracture, 5 cases of sciatic nerve injury, 1 case of femoral nerve injury, and 1 case of squeaking from a ceramic bearing surface.ConclusionCementless THA for adult patients with sequelae from childhood hip infection presents significant technical challenges and a relatively high complication rate. With meticulous surgical planning and anticipation for the key technical challenges frequently encountered, the medium-term clinical and radiographic results of THA in this setting were good with high implant survivorship and patient satisfaction.  相似文献   
18.
ObjectivesThe purposes of this study were to (1) investigate the limits of measurements on scout view in three computed tomography axes, x, y and z and (2) develop a model to provide better understanding of measurement accuracy.MethodsFor the first objective, anteroposterior and lateral scout views of a Catphan phantom 200 mm in diameter and length were acquired with a GE scanner at 21 different table heights. Phantom measurements on scout view were performed by two experienced readers. The comparison of their measures provided estimation of precision. The accuracy was assessed by determining the bias, calculated as the difference between the values measured on scout view and the real phantom size. Second, a model was developed investigating the relationship between the dimensions of the object, its image, and the table height. This relationship was tested on our data.ResultsScout view measurements were precise, with less than 0.53% difference between readers. In addition, small biases of about 1 mm were detected in the z-axis, whatever the table height. In the other axes, serious biases from −13 to +73 mm were measured. Furthermore, at isocentre, overestimations up to 7 mm were shown. The results also indicated that biases in scout view measurements are because of the geometrical projection related to the object-detector distance.ConclusionsMeasurements in the table movement axis are precise and accurate, conferring to scout views an added value for preoperative planning in orthopedic surgery.  相似文献   
19.
《Seminars in Arthroplasty》2015,26(2):108-111
Bone loss is commonly encountered during revision total knee arthroplasty (TKA). Small defects can be adequately managed with cement filling (with or without screws), modular prosthetic augments, and morselized allograft. For larger defects, cancellous impaction grafting and structural allografts have traditionally been utilized. More recently, highly porous tantalum cones and titanium sleeves have been designed to achieve axial and rotational stability in the metaphysis and subsequent biologic fixation. Sleeves are linked to one type of prosthesis, whereas cones are unlinked and can be used with any implant design. Multiple studies have demonstrated excellent survivorship and radiographic osseointegration at mid-term follow-up. This article provides a review of contemporary methods of bone loss management with a focus on highly porous metals and an emphasis on the authors’ preferred method for managing the severe bone loss in revision TKA.  相似文献   
20.
Three‐dimensional (3D) printing technology, virtual reality, and augmented reality technology have been used to help surgeons to complete complex total hip arthroplasty, while their respective shortcomings limit their further application. With the development of technology, mixed reality (MR) technology has been applied to improve the success rate of complicated hip arthroplasty because of its unique advantages. We presented a case of a 59‐year‐old man with an intertrochanteric fracture in the left femur, who had received a prior left hip fusion. After admission to our hospital, a left total hip arthroplasty was performed on the patient using a combination of MR technology and 3D printing technology. Before surgery, 3D reconstruction of a certain bony landmark exposed in the surgical area was first performed. Then a veneer part was designed according to the bony landmark and connected to a reference registration landmark outside the body through a connecting rod. After that, the series of parts were made into a holistic reference registration instrument using 3D printing technology, and the patient's data for bone and surrounding tissue, along with digital 3D information of the reference registration instrument, were imported into the head‐mounted display (HMD). During the operation, the disinfected reference registration instrument was installed on the selected bony landmark, and then the automatic real‐time registration was realized by HMD through recognizing the registration landmark on the reference registration instrument, whereby the patient's virtual bone and other anatomical structures were quickly and accurately superimposed on the real body of the patient. To the best of our knowledge, this is the first report to use MR combined with 3D printing technology in total hip arthroplasty.  相似文献   
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