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The editorial discusses the importance of evaluating systematic reviews and meta-analyses in orthopedic research. It highlights the need for discernment in including source studies in these analyses to avoid unreliable findings. The editorial emphasizes the significance of follow-up duration in assessing the validity of research outcomes and suggests minimum standards for different types of studies. Authors are encouraged to justify surveillance periods and address methodological shortcomings in their papers. The editorial underscores the importance of considering various biases and quality assessments when evaluating research in orthopedics. [Extracted from the article]

This document is an editorial from the journal Clinical Orthopaedics & Related Research® discussing the use of generative artificial intelligence (AI) in clinical orthopaedics and related research. The editorial emphasizes the importance of authors disclosing their use of AI applications in their research and scientific reporting. It also addresses concerns about potential harms and challenges associated with AI tools, such as deepfakes and errors/fraud in scientific reporting. The editorial highlights the responsibility of human authors to proofread and verify the accuracy of content generated by AI tools, as well as the need to disclose any use of AI in creating or modifying figures and visuals. The journal recognizes the potential benefits of using AI applications in scientific reporting, particularly for authors whose first language is not English, but emphasizes the need for authors to take additional responsibilities when using AI tools. The editorial also states that reviewers for the journal should not use generative AI applications or tools during the review process due to copyright and confidentiality concerns, as well as the lack of independent judgment and potential biases of AI tools. The journal's standards for publishing papers on AI-based tools are similar to those for research on any topic, with an emphasis on the importance and novelty of the research questions and the demonstration of practical benefits or identification of specific harms. The editorial concludes by stating that the journal will continue to update its editorial policies and guidelines on the use of AI in response to the evolving nature of the field. [Extracted from the article]

Background: Marine recruits training at Parris Island experienced an unexpectedly high rate of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, despite preventive measures including a supervised, 2-week, pre-entry quarantine. We characterize SARS-CoV-2 transmission in this cohort.Methods: Between May and November 2020, we monitored 2,469 unvaccinated, mostly male, Marine recruits prospectively during basic training. If participants tested negative for SARS-CoV-2 by quantitative polymerase chain reaction (qPCR) at the end of quarantine, they were transferred to the training site in segregated companies and underwent biweekly testing for 6 weeks. We assessed the effects of coronavirus disease 2019 (COVID-19) prevention measures on other respiratory infections with passive surveillance data, performed phylogenetic analysis, and modeled transmission dynamics and testing regimens.Results: Preventive measures were associated with drastically lower rates of other respiratory illnesses. However, among the trainees, 1,107 (44.8%) tested SARS-CoV-2-positive, with either mild or no symptoms. Phylogenetic analysis of viral genomes from 580 participants revealed that all cases but one were linked to five independent introductions, each characterized by accumulation of mutations across and within companies, and similar viral isolates in individuals from the same company. Variation in company transmission rates (mean reproduction number R 0 ; 5.5 [95% confidence interval [CI], 5.0, 6.1]) could be accounted for by multiple initial cases within a company and superspreader events. Simulations indicate that frequent rapid-report testing with case isolation may minimize outbreaks.Conclusions: Transmission of wild-type SARS-CoV-2 among Marine recruits was approximately twice that seen in the community. Insights from SARS-CoV-2 outbreak dynamics and mutations spread in a remote, congregate setting may inform effective mitigation strategies. [ABSTRACT FROM AUTHOR]

Background: Structural cortical bone allografts are a reasonable treatment option for patients with large cortical bone defects caused by trauma, tumors, or complications of arthroplasty. Although structural cortical bone allografts provide the benefit of an osteoconductive material, they are susceptible to fatigue failure (fracture) and carry a risk of disease transmission. Radiation-sterilization at the recommended dose of 25 kGy decreases the risk of disease transmission. However, previous studies demonstrated that radiation sterilization at this dose can negatively impact the high cycle-fatigue life of cortical bone. Although the effects of higher doses of radiation on cortical bone allografts are well described, the effects of lower doses of radiation on a high-cycle fatigue life of cortical bone are poorly understood.Questions/purposes: (1) Does the cycle-fatigue life of human cortical allograft bone vary with gamma radiation dose levels of 0 (control), 10 kGy, 17.5 kGy, and 25 kGy? (2) What differences in Raman spectral biomarkers are observed following varying doses of gamma radiation exposure?Methods: The high-cycle fatigue behavior of human cortical bone specimens was examined at different radiation sterilization doses under physiologic stress levels (35 MPa) and in a 37° C phosphate-buffered saline bath using a custom-designed rotating-bending fatigue device. Six human femora from three donors were obtained for this study (two male, 63 and 61 years old, respectively, and one female, 48 years old). Test specimens were allocated among four treatment groups (0 kGy [control], 10 kGy, 17.5 kGy, and 25 kGy) based on donor and anatomic location of harvest site (both length and cross-sectional quadrant of femoral diaphysis) to ensure equal variation (n = 13 per group). Specimens underwent high-cycle fatigue testing to failure. The number of cycles to failure was recorded. Raman spectroscopy (a noninvasive vibrational spectroscopy used to qualitatively assess bone quality) was used to detect whether any changes in Raman spectral biomarkers occurred after varying doses of gamma radiation exposure.Results: There was a decrease in the log-transformed mean high-cycle fatigue life in specimens irradiated at 25 kGy (5.39 ± 0.32) compared with all other groups (0 kGy: 6.20 ± 0.50; 10k Gy: 6.35 ± 0.79; 17.5 kGy: 6.01 ± 0.53; p = 0.001). Specimens irradiated at 25 kGy were also more likely to exhibit a more brittle fracture surface pattern than specimens with more ductile fracture surface patterns irradiated at 0 kGy, 10 kGy, and 17.5 kGy (p = 0.04). The Raman biomarker for the ratio of the relative amount of disordered collagen to ordered collagen showed a decrease at the 10 kGy radiation level from 1.522 ± 0.025 preirradiation to 1.489 ± 0.024 postirradiation (p = 0.01); no other detectable changes in Raman biomarkers were observed.Conclusion: The high-cycle fatigue life of cortical bone undergoes a nonlinear, dose-dependent decrease with an increase in gamma radiation sterilization in a clinically relevant dose range (0-25 kGy). Importantly, a notable drop-off in the high-cycle fatigue life of cortical bone appeared to occur between 17.5 kGy and 25 kGy, correlating to a sixfold decrease in mean cycles to failure. We speculate that the decrease in the Raman biomarker for disordered collagen at 10 kGy with no loss in high-cycle fatigue life may be caused by an increased amount of nonenzymatic crosslinking of the collagen backbone relative to collagen chain-scission (whereas the benefits of crosslinking may be outweighed by excess scission of the collagen backbone at higher radiation doses), but future studies will need to ascertain whether this in fact is the case.Clinical Relevance: Radiation sterilization at the industry standard of 25 kGy has a substantial negative impact on the high-cycle fatigue life of cortical bone. Given these findings, it is possible to provide a meaningful increase in the high-cycle fatigue life and improve the overall functional lifetime of cortical bone allografts by lowering the radiation-sterilization dose below 25 kGy. Future work on radiation-sterilization methods at these clinically relevant doses is warranted to aid in preserving the high cycle fatigue life of cortical bone allografts while maintaining sterility. [ABSTRACT FROM AUTHOR]

Too many studies about healthcare disparities in our specialty have attributed findings to race without also considering potentially relevant sociodemographic variables. Studies can categorize patients by race and ethnicity when it is important or relevant to do so, and those studies should make it clear what the categories were, and how patients were categorized (such as genetic testing, patient self-report, or whatever it happened to be), but I CORR i will not insist that all papers categorize patients by race or ethnicity. I Clinical Orthopaedics and Related Research® i is proud of its long history of support for work that promotes fairness to musculoskeletal professionals and the patients we treat. [Extracted from the article]

Abstract: Cold injury can result from exercising at low temperatures and can impair exercise performance or cause lifelong debility or death. This consensus statement provides up-to-date information on the pathogenesis, nature, impacts, prevention, and treatment of the most common cold injuries. [ABSTRACT FROM AUTHOR]

In the only survey we could find on the topic, orthopaedic surgeons consistently ranked implant design, biomaterials, and instrumentation as more important to the success of an arthroplasty procedure than the patient, the team, or the surgeon [[3]]. However, as we evaluate those studies' claims, we will insist that studies evaluating a newer biomaterial or implant not support its adoption in clinical practice unless it is better in ways that patients can perceive than are available, well-performing alternatives that have been in use for a longer time. Editorial: What CORR ® Seeks From Papers About New Implants and Techniques. [Extracted from the article]

Case: An 11-year-old boy demonstrated chronic medial hindfoot pain. A 12-year-old boy experienced acute pain and swelling in his right medial ankle and hindfoot after a fall. This is the first report of sustentaculum tali fractures adjacent to a talocalcaneal tarsal coalition, likely resulting from a stress riser created by a rigid subtalar joint. Conclusion: These 2 cases represent unique causes of foot pain in the setting of tarsal coalitions, never before described. Patient-reported outcome measures demonstrated expected improved outcomes after excision of tarsal coalition. Awareness to this possibility will help clinicians treating foot and ankle conditions in children optimize their care. [ABSTRACT FROM AUTHOR]

The author reports that everyone should benefit from the scientific research, regardless of race or ethnicity. Topics discussed include scientific reporting standards on sex and gender; importance of race and ethnicity for genetic and sociocultural reasons; and decreasing importance of orthopaedics across medicine.

An editorial is presented on which questions the support of American Football games by orthopedic surgeons. It expresses the view that football players suffer severe mental illness and also reports pathological changes in the brain of ex players.An overview of the harmful effects of the game and the opinion of surgeons on this factor is presented.

An editorial is presented in which author reports on gene expression analysis in the article of periodical. Topics include information on technologies like Serial Analysis of Gene Expression, RNA-Seq, and commercial in-situ synthesized microarrays which produce data that cannot be directly published in practical manner; guidelines to authors who seek to publish studies on gene expression in periodical; and information on Gene Expression Omnibus which provides database for high throughput data.

The article focuses on the ageing of the musculoskeletal scientist. It states that few orthopedic surgeons devote their careers to research and only a minority of those will receive an NIH (National Institutes of Health) grant and substantial extramural funding for clinician-scientists is scarce. It mentions that Institution-level solutions offer the best balance of plausibility and potential impact and deans must evaluate program size and diversity and cut unproductive program.

Objectives: Functional status at hospital discharge may be a risk factor for adverse events among survivors of critical illness. We sought to examine the association between functional status at hospital discharge in survivors of critical care and risk of 90-day all-cause mortality after hospital discharge.Design: Single-center retrospective cohort study.Setting: Academic Medical Center.Patients: Ten thousand three hundred forty-three adults who received critical care from 1997 to 2011 and survived hospitalization.Interventions: None.Measurements and Main Results: The exposure of interest was functional status determined at hospital discharge by a licensed physical therapist and rated based on qualitative categories adapted from the Functional Independence Measure. The main outcome was 90-day post hospital discharge all-cause mortality. A categorical risk-prediction score was derived and validated based on a logistic regression model of the function grades for each assessment. In an adjusted logistic regression model, the lowest quartile of functional status at hospital discharge was associated with an increased odds of 90-day postdischarge mortality compared with patients with independent functional status (odds ratio, 7.63 [95% CI, 3.83-15.22; p < 0.001]). In patients who had at least 7 days of physical therapy treatment prior to hospital discharge (n = 2,293), the adjusted odds of 90-day postdischarge mortality in patients with marked improvement in functional status at discharge was 64% less than patients with no change in functional status (odds ratio, 0.36 [95% CI, 0.24-0.53]; p < 0.001).Conclusions: Lower functional status at hospital discharge in survivors of critical illness is associated with increased postdischarge mortality. Furthermore, patients whose functional status improves before discharge have decreased odds of postdischarge mortality. [ABSTRACT FROM AUTHOR]

The article reports that a practice-pattern survey demonstrating that an important element of fracture care in practice deviates from solid clinical evidence might consider practice-pattern surveys that present some unexpected or counterintuitive findings. They would be surprised if a sociologist could develop and evaluate a surgical approach to the shoulder.

OBJECTIVE: Hospital readmissions contribute significantly to the cost of inpatient care and are targeted as a marker for quality of care. Little is known about risk factors associated with hospital readmission in survivors of critical illness. We hypothesized that acute kidney injury in patients who survived critical care would be associated with increased risk of 30-day postdischarge hospital readmission, postdischarge mortality, and progression to end-stage renal disease. DESIGN: Two center observational cohort study. SETTING: Medical and surgical ICUs at the Brigham and Women's Hospital and the Massachusetts General Hospital in Boston, Massachusetts. PATIENTS: We studied 62,096 patients, 18 years old and older, who received critical care between 1997 and 2012 and survived hospitalization. INTERVENTIONS: None MEASUREMENTS AND MAIN RESULTS: : All data was obtained from the Research Patient Data Registry at Partners HealthCare. The exposure of interest was acute kidney injury defined as meeting Risk, Injury, Failure, Loss of kidney function, and End-stage kidney disease Risk, Injury or Failure criteria occurring 3 days prior to 7 days after critical care initiation. The primary outcome was hospital readmission in the 30 days following hospital discharge. The secondary outcome was mortality in the 30 days following hospital discharge. Adjusted odds ratios were estimated by multivariable logistic regression models with inclusion of covariate terms thought to plausibly interact with both acute kidney injury and readmission status. Adjustment included age, race (white vs nonwhite), gender, Deyo-Charlson Index, patient type (medical vs surgical) and sepsis. Additionally, long-term progression to End Stage Renal Disease in patients with acute kidney injury was analyzed with a risk-adjusted Cox proportional hazards regression model. The absolute risk of 30-day readmission was 12.3%, 19.0%, 21.2%, and 21.1% in patients with No Acute Kidney Injury, Risk, Injury, Failure, Loss of kidney function, and End-stage kidney disease class Risk, Risk, Injury, Failure, Loss of kidney function, and End-stage kidney disease class Injury, and Risk, Injury, Failure, Loss of kidney function, and End-stage kidney disease class Failure, respectively. In patients who received critical care and survived hospitalization, acute kidney injury was a robust predictor of hospital readmission and post-discharge mortality and remained so following multivariable adjustment. The odds of 30-day post-discharge hospital readmission in patients with Risk, Injury, Failure, Loss of kidney function, and End-stage kidney disease class Risk, Injury, or Failure fully adjusted were 1.44 (95% CI, 1.25-1.66), 1.98 (95% CI, 1.66-2.36), and 1.55 (95% CI, 1.26-1.91) respectively, relative to patients without acute kidney injury. Further, the odds of 30-day post-discharge mortality in patients with Risk, Injury, Failure, Loss of kidney function, and End-stage kidney disease class Risk, Injury, or Failure fully adjusted per our primary analysis were 1.39 (95% CI, 1.28-1.51), 1.46 (95% CI, 1.30-1.64), and 1.42 (95% CI, 1.26-1.61) respectively, relative to patients without acute kidney injury. The addition of the propensity score to the multivariable model did not change the point estimates significantly. Finally, taking into account age, gender, race, Deyo-Charlson Index, and patient type, we observed a relationship between acute kidney injury and development of end-stage renal disease. Patients with Risk, Injury, Failure, Loss of kidney function, and End-stage kidney disease class Risk, Injury, Failure experienced a significantly higher risk of end-stage renal disease during follow-up than patients without acute kidney injury (hazard ratio, 2.03; 95% CI, 1.56-2.65; hazard ratio, 3.99; 95% CI, 3.04-5.23; hazard ratio, 10.40; 95% CI, 8.54-12.69, respectively). CONCLUSIONS: Patients who suffer acute kidney injury are among a high-risk group of ICU survivors for adverse outcomes. In patients treated with critical care who survive hospitalization, acute kidney injury is a robust predictor of subsequent unplanned hospital readmission. In critical illness survivors, acute kidney injury is also associated with the odds of 30-day postdischarge mortality and the risk of subsequent end-stage renal disease. [ABSTRACT FROM AUTHOR]

Objectives: The aim of this study was to evaluate the repeatability of a region of interest (ROI) volume and mean apparent diffusion coefficient (ADC) in standard-of-care 3 T multiparametric magnetic resonance imaging (mpMRI) of the prostate obtained with the use of endorectal coil. Materials and Methods This prospective study was Health Insurance Portability and Accountability Act compliant, with institutional review board approval and written informed consent. Men with confirmed or suspected treatment-naive prostate cancer scheduled for mpMRI were offered a repeat mpMRI within 2 weeks. Regions of interest corresponding to the whole prostate gland, the entire peripheral zone (PZ), normal PZ, and suspected tumor ROI (tROI) on axial T2-weighted, dynamic contrast-enhanced subtract, and ADC images were annotated and assessed using Prostate Imaging Reporting and Data System (PI-RADS) v2. Repeatability of the ROI volume for each of the analyzed image types and mean ROI ADC was summarized with repeatability coefficient (RC) and RC%. Results: A total of 189 subjects were approached to participate in the study. Of 40 patients that gave initial agreement, 15 men underwent 2 mpMRI examinations and completed the study. Peripheral zone tROIs were identified in 11 subjects. Tumor ROI volume was less than 0.5 mL in 8 of 11 subjects. PI-RADS categories were identical between baseline-repeat studies in 11/15 subjects and differed by 1 point in 4/15. Peripheral zone tROI volume RC (RC%) was 233 mm3 (71%) on axial T2-weighted, 422 mm3 (112%) on ADC, and 488 mm3 (119%) on dynamic contrast-enhanced subtract. Apparent diffusion coefficient ROI mean RC (RC%) were 447 × 10−6 mm−2/s (42%) in PZ tROI and 471 × 10−6 mm−2/s (30%) in normal PZ. Significant difference in repeatability of the tROI volume across series was observed (P < 0.005). The mean ADC RC% was lower than volume RC% for tROI ADC (P < 0.05). Conclusions: PI-RADS v2 overall assessment was highly repeatable. Multiparametric magnetic resonance imaging sequences differ in volume measurement repeatability. The mean tROI ADC is more repeatable compared with tROI volume in ADC. Repeatability of prostate ADC is comparable with that in other abdominal organs., Version of Record

Background: Wear of the ultra-high molecular weight polyethylene articular surface has been recognized as a major factor threatening the long-term success of total hip arthroplasty. Manual techniques that have been used to measure femoral head penetration into the polyethylene have been plagued with poor reproducibility and limited accuracy. Using a previously described phantom model simulating an unworn total hip arthroplasty, we previously demonstrated significant limitations in the accuracy of several widely used computerized wear measurement programs. A major component of these inaccuracies is projectional distortion of the femoral head and acetabular shell on the radiograph. These inaccuracies can be "corrected for" mathematically.Methods: In the present follow-up study, we evaluated a widely used hip wear measurement software program (Hip Analysis Suite version 8.0.3.0) that corrects for these projectional errors with use of our previously described "zero wear" phantom model. A cementless metal-backed acetabular component was evaluated radiographically at three different cephalocaudad locations with respect to a radiopaque centering target. At all three positions, the cup was aligned in three different angles of planar abduction (35 degrees , 45 degrees , 55 degrees ) and four angles of planar anteversion (10 degrees , 20 degrees , 30 degrees , 40 degrees ). The accuracy and reproducibility of Hip Analysis Suite version 8.0.3.0 were determined and compared with the results obtained with the earlier version, Hip Analysis Suite version 4.0.Results: Hip Analysis Suite version 8.0.3.0 was significantly more accurate than Hip Analysis Suite version 4.0 for determining linear wear and volumetric wear. Hip Analysis Suite version 8.0.3.0 was significantly more accurate for determining femoral head penetration at the different cephalocaudad acetabular positions and over the range of acetabular component anteversion and abduction angles in comparison with Hip Analysis Suite version 4.0.Conclusions: With use of the same methodology that was used to evaluate earlier versions of Hip Analysis Suite, the present study showed improvement in the accuracy of wear measurement with Hip Analysis Suite version 8.0.3.0 as compared with Hip Analysis Suite version 4.0.Clinical Relevance: On the basis of the results of the present study, Hip Analysis Suite version 8.0.3.0 appears to fulfill the needs for a user-friendly, efficient, and accurate method of assessment of polyethylene wear following total hip arthroplasty. [ABSTRACT FROM AUTHOR]

The article presents the study on the effects of a low and moderate caffeine dose on exogenous CHO oxidation and endurance-exercise performance. The study was conducted in nine trained and familiarized male cyclists whose training and high CHO diet are being controlled. It is found that cyclists with low and moderate caffeine dose showed no significant improvements on their time trial performance. The study concludes that low and moderate doses of caffeine have failed to improve endurance performance in fed, trained subjects.

Purpose: To examine strategies for adjusting the ablation sphere in myopic wavefront laser in situ keratomileusis (LASIK) with reference to preoperative manifest refraction. Setting: Refractive Surgery Service, Moorfields Eye Hospital, London, United Kingdom. Methods: The variance in the 3-month postoperative manifest refraction spherical equivalent (MRSE) results in 295 consecutive cases of myopic wavefront LASIK treated with a nonsystematic, intuitive approach to pretreatment adjustment of the ablation sphere was compared with the variance in modeled results obtained by back-calculation using 4 systematic strategies: (1) no adjustment (No Adj), (2) addition of the difference between the preoperative MRSE and the preoperative 4.0 mm pupil wavefront refraction spherical equivalent (WRSE) (4.0 mm), (3) addition of the difference between the preoperative MRSE and the preoperative maximum pupil WRSE (Max), and (4) addition of the difference between the preoperative MRSE and the preoperative effective blur (EB). The EB is a theoretical value for the dioptric SE of all aberrations at the pupil size calculated for the Hartmann-Shack images acquired (wavefront diameter). A stratified analysis of results for different wavefront diameters was also performed. Results: Variance in the postoperative MRSE was least (0.116) when nonsystematic, intuitive adjustments to the ablation sphere were used. In ascending order, the back-calculated variance was as follows: EB (0.142; P = .09, Bartlett test), 4.0 mm pupil (0.163; P = .004), No Adj (0.171; P = .001), and Max (0.225; P<.0001). There was a strong trend toward reduced variance in results in patients with a larger wavefront diameter. Conclusion: Back-calculation to model results with different pretreatment ablation adjustment strategies may be useful to eliminate unpromising new approaches before clinical trials. [Copyright &y& Elsevier]

Background: In the 1990s, oxidation was found to occur in ultra-high molecular weight polyethylene total joint replacement components following gamma irradiation and prolonged shelf aging in air. Orthopaedic manufacturers developed barrier packaging to reduce oxidation during and after radiation sterilization. The present study explores the hypothesis that polyethylene components sterilized in a low-oxygen environment undergo similar in vivo oxidative mechanisms as inserts sterilized in air. In addition, the potential influence of the different sterilization processes on the wear performance of the polyethylene components was examined. Methods: An analysis of oxidation, wear, and surface damage was performed for forty-eight acetabular liners and 123 tibial inserts. The mean implantation time was 12.3 ± 3.7 years for thirty-one acetabular liners that had been gamma sterilized in air and 4.0 ± 2.5 years for the seventeen acetabular liners that had been gamma sterilized in inert gas. The mean implantation time was 11.0 ± 3.2 years for the twenty-six tibial inserts that had been sterilized in air and 2.8 ± 2.2 years for the ninety-seven tibial inserts that had been gamma sterilized in inert gas. Oxidation and hydroperoxide levels were characterized in loaded and unloaded regions of the inserts. Results: Measurable oxidation and oxidation potential were observed in all cohorts. The oxidation and hydroperoxide levels were regional. Surfaces with access to body fluids were more heavily oxidized than protected bearing surfaces were. This variation appeared to be greater in historical (gamma-in-air-sterilized) components. Regarding wear performance, historical and conventional acetabular liners showed similarwear penetration rates, whereas a low incidence of delamination was confirmed for the conventional tibial inserts in the first decade of implantation. Conclusions: The present study explores the impact of industry-wide changes in sterilization practices for polyethylene. We found lower oxidation and oxidation potential in the conventional acetabular liners and tibial inserts that had been gamma sterilized in inert gas as compared with the historical components that had been gamma sterilized in air. However, we also found strong evidence that conventional components undergo mechanisms of in vivo oxidation similar to those observed following gamma irradiation in air. In addition, gamma sterilization in inert gas did not provide polyethylene with a significant improvement in terms of wear resistance as compared with gamma sterilization in air, except for a lower incidence of delamination in the first decade of implantation for tibial inserts. Clinical Relevance: Our research demonstrates that gamma inert sterilization may have improved, but not completely solved, the problem of polyethylene oxidation for hip and knee arthroplasty. [ABSTRACT FROM AUTHOR]

Background: Osteolysis secondary to stress shielding in patients with a total hip arthroplasty has been attributed to greater stiffness of the prosthetic femoral stem compared with the stiffness of the femur. This concern led to the development of a composite femoral stem implant with a structural stiffness similar to that of the native femur. The stem consists of a cobalt-chromium-alloy core surrounded by polyaryletherketone and titanium mesh for bone ingrowth. The purpose of this study was to determine the intermediate-term clinical, radiographic, and histologic results of the use of this stem.Methods: Twenty-eight patients (nineteen men and nine women) with an average age of 51.3 years underwent primary total hip arthroplasty with the Epoch stem and were followed for an average of 6.2 years. Harris hip scores were determined and radiographic studies were performed preoperatively, postoperatively, and at two-year intervals thereafter. In addition, dual x-ray absorptiometry scans were made up to two years postoperatively to evaluate osseous resorption. Two femora obtained at autopsy thirteen and forty-eight months after surgery were analyzed for bone ingrowth and ongrowth.Results: The Harris hip scores averaged 56 points preoperatively and improved to 97 points at the time of the last follow-up. Dual x-ray absorptiometry scans demonstrated the greatest decrease in mean bone density (27.5%) in Gruen zone 7 at two years. Radiographs demonstrated no instances of migration, and only one hip had osteolysis. All stems had stable osseous fixation. Histologic evaluation of the two femora that had been retrieved at autopsy at thirteen and forty-eight months showed the mean bone ingrowth (and standard deviation) along the entire length of the stem to be 49.62% +/- 13.04% and 73.57% +/- 8.48%, respectively, and the mean bone ongrowth to be 54.18% +/- 7.68% and 80.92% +/- 6.06%, respectively.Conclusions: Intermediate-term follow-up of hips treated with the Epoch stem indicated excellent clinical success, radiographic evidence of osseous integration, and histologic findings of osseous ingrowth and ongrowth. Although the implant has been associated with excellent results in both the short and the intermediate term, longer follow-up will be necessary to assess the long-term function of the implant. [ABSTRACT FROM AUTHOR]

We review our experience using an open 0.5-T magnetic resonance (MR) interventional unit to guide procedures in the prostate. This system allows access to the patient and real-time MR imaging simultaneously and has made it possible to perform prostate biopsy and brachytherapy under MR guidance. We review MR imaging of the prostate and its use in targeted therapy, and describe our use of image processing methods such as image registration to further facilitate precise targeting. We describe current developments with a robot assist system being developed to aid radioactive seed placement. [ABSTRACT FROM AUTHOR]

Background: Ultra-high molecular weight polyethylene degrades during storage in air following gamma sterilization, but the extent of in vivo degradation remains unclear. The purpose of this study was to quantify the extent to which the mechanical properties and oxidation of conventional polyethylene acetabular liners treated with gamma sterilization in air change in vivo.Methods: Fourteen modular cementless acetabular liners were revised at an average of 10.3 years (range, 5.9 to 13.5 years) after implantation. All liners, which had been machined from GUR 415 resin, had been gamma-sterilized in air; the average shelf life was 0.3 year (range, 0.0 to 0.8 year). After removal, the components were expeditiously frozen to minimize ex vivo changes to the polyethylene prior to characterization. The average duration between freezing and testing was 0.6 year. Mechanical properties and oxidation were measured with use of the small-punch test and Fourier transform infrared spectroscopy, respectively, in the loaded and unloaded regions of the liners.Results: There was substantial regional variation in the mechanical properties and oxidation of the retrieved liners. The ultimate load was observed to vary by >90% near the surface. On the average, the rim and the unloaded bearing showed evidence of severe oxidation near the surface after long-term in vivo aging, but these trends were not typically observed on the loaded bearing surface or near the backside of the liners.Conclusions: The mechanical properties of polyethylene that has been gamma-sterilized in air may decrease substantially in vivo, depending on the location in the liner. The most severe oxidation was observed at the rim, suggesting that the femoral head inhibits access of oxygen-containing body fluids to the bearing surface. This is perhaps why in vivo oxidation has not been associated with clinical performance to date. [ABSTRACT FROM AUTHOR]

Background: Thrombophilia has previously been identified as a potential etiologic factor in Legg-Calvé-Perthes disease. We prospectively studied the association between Legg-Calvé-Perthes disease and coagulation abnormalities by comparing seventy-two children who had the disease with 197 healthy controls. Methods: A nonselected, consecutive series of seventy-two patients with Legg-Calvé-Perthes disease (mean age [and standard deviation], 6.6 ± 2.6 years) was studied in their order of referral and compared with 197 healthy controls (mean age, 7.6 ± 5.1 years). Assays were done for factor-V Leiden, prothrombin G20210A, methylenetetrahydrofolate reductase C677T, and plasminogen activator inhibitor-1 4G/5G gene mutations. Levels of anticardiolipin antibodies immunoglobulin G and M (IgG and IgM), homocysteine, protein C, protein S, antithrombin III, and plasminogen activator inhibitor-1 were also measured. Results: The factor-V Leiden mutation was more common in the patients (eight of seventy-two) than in the controls (seven of 197) (chi-square = 5.7, p = 0.017). After we controlled for the false-discovery rate, the case-control difference remained significant (p = 0.017). The odds ratio for the development of Legg-Calvé-Perthes disease in the presence of the factor-V Leiden mutation was 3.39 with a 95% confidence interval of 1.18 to 9.73. A high level of anticardiolipin antibodies (IgG and/or IgM) was found in nineteen of the seventy-two patients compared with twenty-two of the 197 controls (chi-square = 9.5, p = 0.002). After we controlled for the false-discovery rate, the case-control difference remained significant (p = 0.002). The odds ratio of patients with Legg-Calvé-Perthes disease having one or more abnormalities in factor V, anticardiolipin antibody IgG, or anticardiolipin antibody IgM as opposed to normal values for all three variables was 3.29 (95% confidence interval, 1.73 to 6.24; p = 0.0003). Conclusions: Two thrombophilic risk factors, the factor-V Leiden mutation and anticardiolipin antibodies, are associated with Legg-Calvé-Perthes disease, an association that may reflect causality. Level of Evidence: Prognostic study, Level II-1 (retrospective study). See Instructions to Authors for a complete description of levels of evidence. [ABSTRACT FROM AUTHOR]

Radiographic measurements of the wear of total hip arthroplasty implants are indirect measurements based on radiographic determinations of the location of the femoral head relative to the acetabular component. Using the simplest case of zero wear, we assessed the reproducibility and accuracy of two software applications designed to quantify wear from clinical radiographs. After a cobalt-chromium head was glued into the polyethylene liner of a titanium shell, one cross-table lateral radiograph and three anteroposterior pelvic radiographs were made for twelve permutations of acetabular component angulation. The three anteroposterior radiographs differed only with regard to the cephalocaudal positioning of the prosthesis relative to the x-ray tube. To assess method reproducibility, each anteroposterior radiograph was assumed to be both the initial and the latest follow-up radiograph of a wear analysis. To assess method accuracy, each anteroposterior radiograph was paired in a wear analysis with each of the two anteroposterior radiographs made when the component was in the same angulation but at a different cephalocaudal position relative to the tube (one radiograph was the initial follow-up radiograph while the second was the latest follow-up radiograph). The analyses of reproducibility and accuracy were performed both with and without inclusion of the lateral radiograph made with the component in the same angulation. Whereas the results of the reproducibility analyses showed that the methods were consistent in determining the relative positions of the head and shell from a given anteroposterior radiograph or pair of anteroposterior and lateral radiographs, the non-zero wear results obtained in the accuracy analyses proved that these positional determinations were often inaccurate. Thus, while contemporary software methods may yield reproducible results, their accuracy is limited by their inability to correctly determine the position of the head relative to the acetabular component. [ABSTRACT FROM AUTHOR]

In human clinical intervention trials, soy product consumption reduced levels of total cholesterol and low-density lipoprotein cholesterol (LDL-C). In October 1999, the US Food and Drug Administration approved a health claim for the relationship between consumption of soy protein and reduced risk of coronary heart disease. This article provides an overview of the cardiovascular effects of various soy products, including their effects on blood lipids, LDL-C oxidation, blood pressure, and vascular reactivity. Potential mechanism of effect are discussed, emphasizing human clinical intervention trials. Soy consumption improves plasma lipids, although this effect appears to be more pronounced in individuals with elevated cholesterol. Soy and its associated isoflavones also reduce LDL oxidation and improve vascular reactivity. [ABSTRACT FROM AUTHOR]

Presents information on a study which explored a gender-specific health problem associated with the Vietnam War. History of gynecologic cancer among female Vietnam veterans; Association between the risk of cancer and military service; Prevalence of gynecologic organ cancers in Vietnam war veterans.