Motion acquisition of gait characteristics one week after total hip arthroplasty: a factor analysis.

INTRODUCTION: Clinical gait analysis can be used to evaluate the recovery process of patients undergoing total hip arthroplasty (THA). The postoperative walking patterns of these patients can be significantly influenced by the choice of surgical approach, as each procedure alters distinct anatomical structures. The aim of this study is twofold. The first objective is to develop a gait model to describe the change in ambulation one week after THA. The secondary goal is to describe the differences associated with the surgical approach. MATERIALS AND METHODS: Thirty-six patients undergoing THA with lateral (n = 9), anterior (n = 15), and posterior (n = 12) approaches were included in the study. Walking before and 7 days after surgery was recorded using a markerless motion capture system. Exploratory Factor Analysis (EFA), a data reduction technique, condensed 21 spatiotemporal gait parameters to a smaller set of dominant variables. The EFA-derived gait domains were utilized to study post-surgical gait variations and to compare the post-surgical gait among the three groups. RESULTS: Four distinct gait domains were identified. The most pronounced variation one week after surgery is in the Rhythm (gait cycle time: + 32.9 % ), followed by Postural control (step width: + 27.0 % ), Phases (stance time: + 11.0 % ), and Pace (stride length: -  9.3 % ). In postsurgical walking, Phases is statistically significantly different in patients operated with the posterior approach compared to lateral (p-value = 0.017) and anterior (p-value = 0.002) approaches. Furthermore, stance time in the posterior approach group is significantly lower than in healthy individuals (p-value < 0.001). CONCLUSIONS: This study identified a four-component gait model specific to THA patients. The results showed that patients after THA have longer stride time but shorter stride length, wider base of support, and longer stance time, although the posterior group had a statistically significant shorter stance time than the others. The findings of this research have the potential to simplify the reporting of gait outcomes, reduce redundancy, and inform targeted interventions in regards to specific gait domains.

The value of Interferon ß in multiple sclerosis and novel opportunities for its anti-viral activity: a narrative literature review.

Interferon-beta (IFN-ß) for Multiple Sclerosis (MS) is turning 30. The COVID-19 pandemic rejuvenated the interest in interferon biology in health and disease, opening translational opportunities beyond neuroinflammation. The antiviral properties of this molecule are in accord with the hypothesis of a viral etiology of MS, for which a credible culprit has been identified in the Epstein-Barr Virus. Likely, IFNs are crucial in the acute phase of SARS-CoV-2 infection, as demonstrated by inherited and acquired impairments of the interferon response that predispose to a severe COVID-19 course. Accordingly, IFN-ß exerted protection against SARS-CoV-2 in people with MS (pwMS). In this viewpoint, we summarize the evidence on IFN-ß mechanisms of action in MS with a focus on its antiviral properties, especially against EBV. We synopsize the role of IFNs in COVID-19 and the opportunities and challenges of IFN-ß usage for this condition. Finally, we leverage the lessons learned in the pandemic to suggest a role of IFN-ß in long-COVID-19 and in special MS subpopulations.

A virtual environment to evaluate the arm volume for lymphedema affected patients.

BACKGROUND AND OBJECTIVE: The paper presents a novel procedure based on 3D scanning and 3D modelling to automatically assess linear and volumetric measurements of an arm and to be further applied to patients affected by post breast cancer lymphedema. The aim is the creation of a virtual platform easily usable by medical personnel to get more objective evaluations during the lymphedema treatment. METHODS: The procedure is based on the 3D scanning of the arm using the Occipital Structure Sensor and an ad-hoc developed application, named Lym 3DLab. Lym 3DLab emulates the traditional measurement methods, which consist in taking manual circumference measurements or using the water displacement method. These measurements are also used to design the compression stockings, the typical orthopaedic device used for lymphedema treatment. A validation test has been performed to compare the measurements computed by Lym 3DLab with both water displacement and manual circumference measurements. Eight volunteers have been involved who are not affected by lymphedema. Furthermore, a specific usability test has been performed to evaluate the 3D scanning procedure by involving four physiotherapists. RESULTS: The comparison between the volumes has highlighted how all the 3D acquired models have their volumes inside a range of acceptability. This range has been defined by considering the sensitivity error of the tape measure used to measure the water displacement. The comparison between the perimeters of cross sections computed with Lym 3DLab and the circumference measurements has shown results that are very accurate with an average difference of 2 mm. The measure errors have been considered negligible by the medical personnel who have evaluated the proposed procedure more accurate than the traditional ones. The test with physiotherapists has shown a high level of usability of the whole virtual environment, but the 3D scanning procedure requires an appropriate training of the personnel to make the 3D acquisition as fast and efficient as possible. CONCLUSIONS: The achieved results and the physiotherapists' feedback allow planning a future test with patients affected by lymphedema in collaboration with the hospital. A further test has been planned to use the computed measurements to design orthopaedic compression stockings.

Toxic properties of microsome-associated alpha-synuclein species in mouse primary neurons.

α-synuclein (αS) is a small protein that self-aggregates into α-helical oligomer species and subsequently into larger insoluble amyloid fibrils that accumulate in intraneuronal inclusions during the development of Parkinson's disease. Toxicity of αS oligomers and fibrils has been long debated and more recent data are suggesting that both species can induce neurodegeneration. However while most of these data are based on differences in structure between oligomer and aggregates, often preassembled in vitro, the in vivo situation might be more complex and subcellular locations where αS species accumulate, rather than their conformation, might contribute to enhanced toxicity. In line with this observation, we have shown that αS oligomers and aggregates are associated with the endoplasmic reticulum/microsomes (ER/M) membrane in vivo and how accumulation of soluble αS oligomers at the ER/M level precedes neuronal degeneration in a mouse model of α-synucleinopathies. In this paper we took a further step, investigating the biochemical and functional features of αS species associated with the ER/M membrane. We found that by comparison with non-microsomal associated αS (P10), the ER/M-associated αS pool is a unique population of oligomers and aggregates with specific biochemical traits such as increased aggregation, N- and C-terminal truncations and phosphorylation at serine 129. Moreover, when administered to murine primary neurons, ER/M-associated αS species isolated from diseased A53T human αS transgenic mice induced neuronal changes in a time- and dose-dependent manner. In fact the addition of small amounts of ER/M-associated αS species from diseased mice to primary cultures induced the formation of beads-like structures or strings of fibrous αS aggregates along the neurites, occasionally covering the entire process or localizing at the soma level. By comparison treatment with P10 fractions from the same diseased mice resulted in the formation of scarce and small puncta only when administered at high amount. Moreover, increasing the amount of P100/M fractions obtained from diseased and, more surprisingly, from presymptomatic mice induced a significant level of neuronal death that was prevented when neurons were treated with ER/M fractions immunodepleted of αS high molecular weight (HMW) species. These data provide the first evidence of the existence of two different populations of αS HMW species in vivo, putting the spotlight on the association to ER/M membrane as a necessary step for the acquisition of αS toxic features.