The direct costs of paternal care are relatively well documented in primates, however little research has explored these effects in monogamous rodents. The present study examines the long-term effects that pairing and parenting have on male prairie voles. We hypothesized that there would be a significant weight loss over the course of pairing and parenting, presumably from the energetic demands that accompany these changes in social condition. In a longitudinal study, we followed ten male prairie voles through being housed with their brother; paired with a female; and caring for three consecutive litters. We found a significant drop in bodyweight across time, with maximum weight loss near the weaning of the first litter. At that same time, feeding increased, leading to possible recovery in weight; however, leptin levels dropped precipitously across time and did not recover. Corticosterone did not change significantly across time points, and overall activity levels also did not vary significantly over the course of the study. In addition, newly paired males showed a significant increase in preference for a 2% sucrose solution during a three-hour test, indicating a metabolic need for more calories. A cross-sectional study confirmed leptin and corticosterone findings, and showed significant loss of subcutaneous (inguinal) fat in males that had cared for a litter of pups, when compared to males housed with their brothers or newly paired males. These results suggest that cohabitation with a female, and caring for pups, all have costs for male prairie voles.

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

We present a unique case of a symptomatic adverse local tissue reaction in a patient with a ceramic-on-ceramic total hip bearing surface. To our knowledge, this pathological finding has not yet been described in a ceramic-on-ceramic articulation without a cobalt-chromium alloy trunnion or modular neck component as a source of metal wear. We conclude that despite its mechanical mostly benign wear characteristics, ceramic wear debris is not entirely inert and may lead to the development of adverse local tissue reaction.

No abstract

Background Citation analysis is commonly used to evaluate the impact of academic publications within an area of study. The purpose of this study is to review the publications with the highest Altmetric scores related to total hip arthroplasty (THA) and total knee arthroplasty (TKA) and assess the correlation with traditional bibliometrics. Methods Altmetric scores were obtained for the top articles relating to THA and TKA and organized from highest to lowest scores. The Clarivate Analytics Web of Knowledge database was used to search the top articles by Altmetric score. Articles meeting inclusion criteria were reviewed for various metrics, including number of citations, journal impact factor at the time of publication, and study type and design. Results The top THA and TKA publications were cited 3042 times and 7523 times, respectively. The former were published in journals with an average impact factor of 17.861, and the latter in journals with an average impact factor of 15.564. For THA, Altmetric score demonstrated a significant, weakly positive correlation with the number of citations ( P = .008). For TKA, Altmetric score was found to have a significant, weakly positive correlation with impact factor of journal ( P = .04); however, it was nonsignificant for citation count ( P = .11). When one outlier is removed, the correlation with citation count is statistically significant ( P = .009). Conclusion While alternative metrics cannot replace traditional bibliometrics, they may serve a complimentary role in describing the influence of research. Thus, the Altmetric score represents an additional tool to identify the most influential articles to guide learning and evidence-based practice.