Fixed or mobile bearing unicompartmental knee replacement? A comparative cohort study

Unicompartmental knee replacement (UKR) for anteromedial osteoarthritis is a well-established technique. Numerous clinical outcome studies demonstrate good medium and long-term results. The aim of this prospective study was to compare the complications and short-term clinical outcome of the St. Georg Sled, a fixed bearing UKR, with the Oxford mobile bearing UKR. Outcome at 2 years was assessed using the Bristol knee score and the Oxford knee score; in addition, complications occurring since formal scoring at 2-year follow-up were recorded. A total of 47 Oxford UKRs and 57 St. Georg Sled UKRs were performed in 91 patients, none of whom were lost to follow-up. At 2 years, both outcome measures were better for the St. Georg Sled Group. The pain component of the Bristol knee score was significantly better for this group (p-value = 0.013). Three patients in the Oxford group had bearing dislocations and a further four patients required revision (mean time to revision 3.0 years). In the St. Georg Sled group, three patients required revisions (mean time to revision 3.4 years). These results demonstrate that in the short-term, the Oxford mobile bearing prosthesis has a higher re-operation rate and that the St. Georg Sled achieves better pain relief. The functional scores of the two groups were similar.     

Comparison of the middle-aged and older users’ adoption of mobile health services in China

ObjectiveGiven the increasing number of older people, China has become an aging society. A mobile health service is a type of health informatics that provides personalized healthcare advice to those who require it, especially the older people and the middle-aged. However, few studies consider the adoption of mobile health services with regard to older and middle-aged users. This paper explored a research model based on the value attitude behavior model, theory of planned behavior, and four aging characteristic constructs to investigate how older and middle-aged citizens adopted mobile health services.MethodThe hypothesized model was empirically tested using data collected from a survey of 424 residents older than 40 years in China. Structural equation modeling was used to estimate the significance of the path coefficients.ResultsThe findings revealed that (1) perceived value, attitude, perceived behavior control, and resistance to change can be used to predict intention to use mobile health services for the middle-aged group; (2) perceived value, attitude, perceived behavior control, technology anxiety, and self-actualization need positively affected the behavior intention of older users; and (3) subjective norm and perceived physical condition showed no significant effects on the behavior intention to use mobile health services for the two groups. The theoretical and practical implications and contributions of this study are then discussed.     

What do we know about mobile applications for diabetes self-management? A review of reviews

Diabetes is a chronic illness with significant health consequences, especially for those who are unable to adhere to the complex treatment regimen. Self-management tasks such as regular medication and insulin use, frequent blood sugar checks, strict diet management, and consistent exercise can be quite challenging. Mobile technologies, specifically mobile applications (apps), present a unique opportunity to help patients improve adherence to these behaviors. The availability of commercial diabetes self-management apps is increasing rapidly, making it difficult for patients and providers to stay informed about app options. A number of reviews have described commercial app technology and use for patients with diabetes. The aims of this article are to summarize the results and themes of those reviews, to review outcomes of apps described in the research literature, and to identify areas for further consideration in the use of mobile apps for diabetes self-management.     

Health behavior models in the age of mobile interventions: are our theories up to the task?

Mobile technologies are being used to deliver health behavior interventions. The study aims to determine how health behavior theories are applied to mobile interventions. This is a review of the theoretical basis and interactivity of mobile health behavior interventions. Many of the mobile health behavior interventions reviewed were predominately one way (i.e., mostly data input or informational output), but some have leveraged mobile technologies to provide just-in-time, interactive, and adaptive interventions. Most smoking and weight loss studies reported a theoretical basis for the mobile intervention, but most of the adherence and disease management studies did not. Mobile health behavior intervention development could benefit from greater application of health behavior theories. Current theories, however, appear inadequate to inform mobile intervention development as these interventions become more interactive and adaptive. Dynamic feedback system theories of health behavior can be developed utilizing longitudinal data from mobile devices and control systems engineering models.     

Information access at the point of care: what can we learn for designing a mobile CPR system?

OBJECTIVES: Hospitals have started to migrate their paper-based records to computerized patient records (CPR). The majority of today's CPR systems are stationary, which means that physicians use a clinical workstation to access CPR information. But health care professionals need to request and enter information at different locations, for example, on their daily ward round. This suggests the use of mobile computers, enabling an ubiquitous access to needed data. Different studies show that health care professionals are reluctant to use poorly designed mobile CPR systems, as the work at the point of care is very time-pressured and hectic. To design a system with high acceptance, it is essential to obtain empirical insight into the work practices and context in which the mobile CPR system will be used. METHOD: We investigated the physicians' work with the patient record during their daily round. With the help of a compact notation method, the physicians' interaction with the information system was recorded in real time. Fourteen physicians from three different departments (internal medicine, surgery, and geriatrics) of a middle-sized Swiss hospital participated in our study. RESULTS: Physicians have clear access preferences when they interact with the patient record during their daily round. There exists a clear profile of access frequencies and patterns, respectively. As an example, approximately 50% of all patient record accesses concern information about medications, vital signs and lab test results. DISCUSSION/CONCLUSION: A CPR system which is designed to reflect the access frequencies and patterns should improve the efficiency of data entry and retrieval and thus result in a system with high acceptance among physicians in the demanding environment during hospital rounds.     

Mobile bearing or fixed bearing? A meta-analysis of outcomes comparing mobile bearing and fixed bearing bilateral total knee replacements

BackgroundTo compare outcomes between mobile-bearing (MB) and fixed-bearing (FB) in bilateral total knee replacements.MethodsThe MEDLINE, EMBASE and Cochrane Library databases were searched. Randomized controlled trials of bilateral total knee arthroplasty with one of each design implanted were identified. Weighted mean differences (WMDs) and pooled risk ratios (RRs) were calculated using fixed- or random-effects models.ResultsTwelve studies were identified with a total of 807 patients and 1614 knees. All RCTs were of high quality with a low risk of bias. No statistical difference was found between MB and FB at 2- to 5-year follow-up in terms of America Knee Society score (WMD: − 1.29, 95% CI: − 5.65 to 3.06), pain score (WMD: − 3.26, 95% CI: − 10.45 to 3.93), range of motion (WMD: − 4.16, 95% CI: − 9.97 to 1.66), reoperation (RR: 1.00, 95% CI: 0.28 to 3.60), and radiolucent lines (RR: 1.51, 95% CI: 0.70 to 3.24). The results were similar at 1-, 5- to 8-, or > 8-year follow-up. Patient's satisfaction (RR: 0.85, 95% CI: 0.54 to 1.34), and complication (≤ 2-year, RR: 0.55, 95% CI: 0.29 to 1.04; > 2-year, RR: 1.0, 95% CI = 0.73 to 1.38) also showed no difference between two groups.ConclusionsBased on this meta-analysis we are unable to detect the superiority of MB as compared to FB. More randomized trials with a larger sample size and longer follow-up are needed to evaluate these two kinds of prosthesis.Level of evidenceTherapeutic Level II.     

The use of a ‘phantom scalp’ to assess the possible direct pickup of mobile phone handset emissions by electroencephalogram electrode leads

A ‘Phantom Scalp’ was constructed from a conducting foam mat to form a layer under a 62-electrode electroencephalogram cap closely approximating the electrical properties of a human scalp. The mat was placed over a polystyrene manikin head to preserve a correct anatomical arrangement. Electrical signals were recorded with a Global System for Mobile (GSM) communications mobile phone handset in place against the side of the ‘head’. Amplitude spectra were compared for three phone conditions: ‘off’, ‘standby’ and ‘transmit’. At 217 Hz, significant differences were obtained between ‘transmit’ and the other two conditions, but no significant differences were noted for the physiologically important range 0.5–30 Hz. An anomalous difference was noted for one electrode in the range 30–45 Hz.     

LCS mobile bearing total knee arthroplasty without patellar resurfacing. Does the unresurfaced patella affect outcome? Survivorship at a minimum 10-year follow-up

BackgroundPatellar resurfacing during total knee arthroplasty (TKA) remains controversial. The aim of this study was to evaluate the long-term outcomes of a mobile-bearing TKA without patellar resurfacing.MethodsWe assessed the outcomes in 503 patients (600 knees) who had cemented LCS (low contact stress) mobile bearing TKA without patellar resurfacing at a minimum follow-up of 10 years. Clinical outcome scores and radiological assessment were used.ResultsFour knees were revised, two had bearing dislocation and nine patients (1.5%) had secondary resurfacing for anterior knee pain. There were no radiolucent lines or osteolytic defects on radiographic evaluation.The overall survivorship was 97.8% with re-operation for any reason as the endpoint.ConclusionNon-resurfacing of the patella does not adversely affect the outcome of the LCS mobile bearing TKA at minimum 10 years follow-up.     

Descended and mobile larynx, vocal tract elongation and rutting roars in male goitred gazelles (Gazella subgutturosa Güldenstaedt, 1780)

Similar to male humans, Homo sapiens, the males of a few polygynous ruminants - red deer Cervus elaphus, fallow deer Dama dama and Mongolian gazelle Procapra gutturosa- have a more or less enlarged, low-resting larynx and are capable of additional dynamic vocal tract elongation by larynx retraction during their rutting calls. The vocal correlates of a large larynx and an elongated vocal tract, a low fundamental frequency and low vocal tract resonance frequencies, deter rival males and attract receptive females. The males of the polygynous goitred gazelle, Gazella subgutturosa, provide another, independently evolved, example of an enlarged and low-resting larynx of high mobility. Relevant aspects of the rutting behaviour of territorial wild male goitred gazelles are described. Video and audio recordings served to study the acoustic effects of the enlarged larynx and vocal tract elongation on male rutting calls. Three call types were discriminated: roars, growls and grunts. In addition, the adult male vocal anatomy during the emission of rutting calls is described and functionally discussed using a 2D-model of larynx retraction. The combined morphological, behavioural and acoustic data are discussed in relation to the hypothesis of sexual selection for male-specific deep voices, resulting in convergent features of vocal anatomy in a few polygynous ruminants and in human males.     

Savannah roars: The vocal anatomy and the impressive rutting calls of male impala (Aepyceros melampus) – highlighting the acoustic correlates of a mobile larynx

A retractable larynx and adaptations of the vocal folds in the males of several polygynous ruminants serve for the production of rutting calls that acoustically announce larger than actual body size to both rival males and potential female mates. Here, such features of the vocal tract and of the sound source are documented in another species. We investigated the vocal anatomy and laryngeal mobility including its acoustical effects during the rutting vocal display of free-ranging male impala (Aepyceros melampus melampus) in Namibia. Male impala produced bouts of rutting calls (consisting of oral roars and interspersed explosive nasal snorts) in a low-stretch posture while guarding a rutting territory or harem. For the duration of the roars, male impala retracted the larynx from its high resting position to a low mid-neck position involving an extensible pharynx and a resilient connection between the hyoid apparatus and the larynx. Maximal larynx retraction was 108 mm based on estimates in video single frames. This was in good concordance with 91-mm vocal tract elongation calculated on the basis of differences in formant dispersion between roar portions produced with the larynx still ascended and those produced with maximally retracted larynx. Judged by their morphological traits, the larynx-retracting muscles of male impala are homologous to those of other larynx-retracting ruminants. In contrast, the large and massive vocal keels are evolutionary novelties arising by fusion and linear arrangement of the arytenoid cartilage and the canonical vocal fold. These bulky and histologically complex vocal keels produced a low fundamental frequency of 50 Hz. Impala is another ruminant species in which the males are capable of larynx retraction. In addition, male impala vocal folds are spectacularly specialized compared with domestic bovids, allowing the production of impressive, low-frequency roaring vocalizations as a significant part of their rutting behaviour. Our study expands knowledge on the evolutionary variation of vocal fold morphology in mammals, suggesting that the structure of the mammalian sound source is not always human-like and should be considered in acoustic analysis and modelling.     

Virulence and resistance properties of E. coli isolated from urine samples of hospitalized patients in Rio de Janeiro,Brazil – The role of mobile genetic elements

Extraintestinal pathogenic E. coli (ExPEC) is the most frequent etiological agent of urinary tract infections (UTIs). Particular evolutionary successful lineages are associated with severe UTIs and higher incidences of multidrug resistance. Most of the resistance genes are acquired by horizontal transfer of plasmids and other mobile genetic elements (MGEs), and this process has been associated with the successful dissemination of particular lineages. Here, we identified the presence of MGEs and their role in virulence and resistance profiles of isolates obtained from the urine of hospitalized patients in Brazil. Isolates belonging to the successful evolutionary lineages of sequence type (ST) 131, ST405, and ST648 were found to be multidrug-resistant, while those belonging to ST69 and ST73 were often not. Among the ST131, ST405, and ST648 isolates with a resistant phenotype, a high number of mainly IncFII plasmids was identified. The plasmids contained resistance cassettes, and these were also found within phage-related sequences and the chromosome of the isolates. The resistance cassettes were found to harbor several resistance genes, including bla_CTX-M-15. In addition, in ST131 isolates, diverse pathogenicity islands similar to those found in highly virulent ST73 isolates were detected. Also, a new genomic island associated with several virulence genes was identified in ST69 and ST131 isolates. In addition, several other MGEs present in the ST131 reference strain EC958 were identified in our isolates, most of them exclusively in ST131 isolates. In contrast, genomic islands present in this reference strain were only partially present or completely absent in our ST131 isolates. Of all isolates studied, ST73 and ST131 isolates had the most similar virulence profile. Overall, no clear association was found between the presence of specific MGEs and virulence profiles. Furthermore, the interplay between virulence and resistance by acquiring MGEs seemed to be lineage dependent. Although the acquisition of IncF plasmids, specific PAIs, GIs, and other MGEs seemed to be involved in the success of some lineages, it cannot explain the success of different lineages, also indicating other (host) factors are involved in this process. Nevertheless, the detection, identification, and surveillance of lineage-specific MGEs may be useful to monitor (new) emerging clones.     

Does evidence support the use of mobile phone apps as a driver for promoting healthy lifestyles from a public health perspective? A systematic review of Randomized Control Trials

ObjectiveThe aim of this systematic review was to find a scientific evidence on the efficacy of apps in promoting healthy lifestyles.MethodsThe research was carried out according to PRISMA Statement. Pubmed, Embase and Google Scholar searches were carried out up to September 2016 focusing on randomized control trials (RCTs).ResultsForty RCTs were selected. Most of the studies targeted weight management, PA and healthy eating (N = 35). A few RCTs focused on apps designed to sun protection, smoking cessation and alcohol consumption (N = 5). Only 10 RCTs (25%) found statistical difference between intervention and control groups for all the outcomes measured. Most of the studies had a short follow-up (65%, less than 6 months) and half of them a very small sample size (fewer than 100 subjects).ConclusionOverall, the evidence so far showed a modest efficacy of apps in health promotion.Practice implicationsThere is a need to improve the overall quality of intervention studies focused on mobile apps in order to understand if they could became a valuable tool in support of health professionals and their efforts to promote education and health.     

Comparison of three mobile devices for measuring R–R intervals and heart rate variability: Polar S810i, Suunto t6 and an ambulatory ECG system

The first aim of this study was to compare an ambulatory five-lead ECG system with the commercially available breast belt measuring devices; Polar S810i and Suunto t6, in terms of R–R interval measures and heart rate variability (HRV) indices. The second aim was to compare different HRV spectral analysis methods. Nineteen young males (aged between 22 and 31 years, median 24 years) underwent simultaneous R–R interval recordings with the three instruments during supine and sitting rest, moderate dynamic, and moderate to vigorous static exercise of the upper and lower limb. For each subject, 17 R–R interval series of 3-min length were extracted from the whole recordings and then analyzed in frequency domain using (1) a fast Fourier transform (FFT), (2) an autoregressive model (AR), (3) a Welch periodogram (WP) and (4) a continuous wavelet transform (CWT). Intra-class correlation coefficients (ICC) and Bland–Altman limits of agreement (LoA) method served as criteria for measurement agreement. Regarding the R–R interval recordings, ICC (lower ICC 95% confidence interval >0.99) as well as LoA (maximum LoA: −15.1 to 14.3 ms for ECG vs. Polar) showed an excellent agreement between all devices. Therefore, the three instruments may be used interchangeably in recording and interpolation of R–R intervals. ICCs for HRV frequency parameters were also high, but in most cases LoA analysis revealed unacceptable discrepancies between the instruments. The agreement among the different frequency transform methods can be taken for granted when analyzing the normalized power in low and high frequency ranges; however, not when analyzing the absolute values.