Gapful electrons in a vortex core in granular superconductors

We calculate the quasiparticle density of states (DoS) inside the vortex core in a granular superconductor, generalizing the classical solution applicable for dirty superconductors. A discrete version of the Usadel equation for a vortex is derived and solved numerically for a broad range of parameters. Electron DoS is found to be gapful when the vortex size $\xi$ becomes comparable to the distance between neighboring grains $l$. Minigap magnitude $E_g$ grows from zero at $\xi \approx 1.4 l$ to third of superconducting gap $\Delta_0$ at $\xi \approx 0.5 l$. The absence of low-energy excitations is the main ingredient needed to understand strong suppression of microwave dissipation recently observed in a mixed state of granular Al

Instability of the Knee Joint Before and After Reconstruction of the Anterior Cruciate Ligament According to the Questionnaire

Background: The instability of the knee joint after a rupture of the anterior cruciate ligament in recent decades has acquired the character of a meme among Russian orthopedists with a very wide use and meaning. Aim: In this study, we tried to find out how often the phenomenon of instability occurs and how it can be associated with joint injury. Methods: The method of questioning, collecting anamnesis in patients at the primary orthopedic appointment and in patients after surgical reconstruction by the method of questioning was used. Results: The data collected in 433 patients with a verified rupture of the anterior cruciate ligament showed that 77% experienced a feeling of instability in the knee joint, and 19% did not experience them at all. Arthroscopic reconstruction was performed in 297 patients, 71 of them were surveyed. The period of time from surgery to questioning was 6.5 years on average. Not all patients can note the moment of injury. Even if there was an injury to the knee joint, 10% of patients do not note the development of instability immediately after injury. The duration of the sensation of instability in the knee joint after injury varies from one week to a year or more. The very moment of joint instability is accompanied by pain in more than half of the cases. At the same time, 12% of the respondents had no pain. A third of the respondents had never noted episodes of instability in the knee joint before surgical reconstruction. But 11% had such episodes daily. In the postoperative period, 27% note the recurrence of joint instability at different times. Conclusions: Thus, an ACL tear does not equal knee instability. Instability is not a condition, but a short-term episode that occurs during the period of support and leads to buckling of the limb

The functional instrumental test of flexion-extension motion in the radiocarpal joint: reference parameters

BACKGROUND: The stroke represents a significant medical-social problem due to its high morbidity and mortality with a tendency towards increasing the overall occurrence rates. A total 80% of the patients show persisting impaired functions of the upper limb. The current approaches, such as Clinical scales and Questionnaires, are being criticized for subjectivity and insufficient precision. It is necessary to develop an instrumental method for evaluating the functions of the upper limb, the method that is applicable in the clinical settings. AIM: To develop a functional test for the objective diagnostics of the wrist joint functions, applicable in the clinical settings. METHODS: A functional test was proposed for evaluating the biomechanics of the radiocarpal joint by means of using the inertial sensors. The research sample was a group of 15 healthy volunteers (5 males and 10 females aged from 23 to 33 years), not having any joint diseases or neurological disorders. The research was carried out within a period of one year (2022–2023). The primary endpoint was the determination of the amplitude, the time and the motion trajectory in the wrist joint when performing two tests - the “Wrist-0” and “Wrist-flex”. An assessment was done of the duration of the motion cycle, of the motion maximal amplitude and phase. RESULTS: The evaluation of the upper limb functions using the clinical scales (ARAT, FMA-UE, MRC) has demonstrated, that the parameters correspond to the ones in healthy individuals. When using the “Wrist-0” test, the motion amplitude was significantly lower than in the «Wrist-flex» test (p 0.05). No statistically significant differences were found in the motion amplitude between the right and left limbs determined using both tests (p 0.05). The maximal flexion phase for the “Wrist-0” tests occurs significantly earlier than for the “Wrist-flex” test for the right hand (p 0.05). The duration of the motion cycle did not significantly differ between the tests for the right hand (p 0.05) and was significantly higher for the “Wrist-flex” test in the left hand (p 0.05). CONCLUSION: A set of reference values was established for the functional tests. Insignificant differences were reported for the functions of the right and left radiocarpal joints. The test proposed requires insignificant time for its implementation and it can be used for objective diagnostics of the radiocarpal joint functions in patients

Multi-channel functional electrostimulation: the method of restoring the walking function in patients with a past history of acute cerebrovascular event

Multi-channel functional electrostimulation (MFES) represents a promising method for the rehabilitation of post-stroke patients, aimed at restoring the walking function in various periods after an acute cerebrovascular event. The review systematizes the modern concepts of using the MFES in patients with the consequences of cerebral stroke, analyzing the technical parameters of stimulation, the methodical approaches to conducting the procedures and the clinical efficiency of the method. The analysis of literature data demonstrates significant variability of MFES protocols: the stimulation frequency varies from 20 to 100 Hz, the duration of the procedure ranges from 15 to 60 minutes, the treatment course can last from 3 to 30 weeks. The main targets of stimulation are the four groups of muscles in the lower limbs — the anterior tibial muscle, the plantar flexors, the quadriceps muscle of thigh and the group of muscles on the posterior surface of thigh. The synchronization of stimulation with the walking cycle is conducted predominantly by means of contact sensors, accelerometers and electromyographic signals; modern developments include the inertial systems and the machine learning algorithms. The review presents a combined analysis of the technical aspects of MFES from the point of view of staging of motor learning and individualization of the stimulation parameters. Special attention was paid to the integration of MFES with the robotic devices, including the exoskeletons, which represents a new trend in rehabilitation. Along with the absence of the unified criteria for choosing the stimulation parameters, it is worth noting that there is a necessity of differentiated approach depending on the type of motor disorders, on the duration of the disease and on the cognitive capabilities of the patient. The analysis presented justifies the necessity of developing personalized MFES protocols and arranging a large-scale research for optimizing the stimulation parameters in the rehabilitation of post-stroke patients

Targeted training of the function of walking according to the stance and single support phase in patients in the early recovery period of cerebral stroke

Background: The phases of support and single support on a limb are significant basic parameters of walking (phase of support means the whole limb support time, while the phase of single support is when only one limb is on the ground). Both can be used as targets for biofeedback training. Aim: to investigate the effectiveness of both target parameters for training the function of walking with biofeedback in patients in the early recovery period of cerebral stroke. Methods: The study involved 40 patients, 20 in each group, who underwent a training course to harmonize walking: the first group for the period of support, and the second group for the period of single support. The control group of healthy people also consisted of 20 people. We studied the spatiotemporal parameters of walking at an arbitrary pace at the beginning and after the end of the training course, as well as classical clinical scales. The treadmill training consisted of 10 sessions. Results: The clinical and biomechanical parameters of walking changed their values in the direction of a significant improvement in the performance. At the same time, the biomechanical parameters of the second group indicated a more severe functional state before the start of the treatment, with the same clinical parameters according to the Barthel scale, Rivermead Mobility Index, modified Rankin scale, rehabilitation routing scale, and manual muscle testing. In the first group, indirect data were obtained on the possible effect of the target indicator on the training and direct data on its effect on the function of a healthy limb, which also allows increasing the load on the paretic one. In the second group, there were no reliable data on the effect of biofeedback training on the functional outcome. Conclusion: The conducted study showed that the classical clinical assessment of the patient's condition may not correspond to the instrumental functional study of walking. When using the support period as the training target parameter, indirect evidence was obtained that such a training is effective

The use of the long peroneal muscle tendon as an autograft during the primary plastics of the anterior cruciate ligament: a systematic review

The anterior cruciate ligament injuries take the leading place among all the injuries of the knee joint. The rupture of the anterior cruciate ligament most frequently occurs during sports-related and high-energy traumas. The aim of the present systematic review is to compare the results obtained after the anterior cruciate ligament plastics with using the long peroneal muscle tendon and the autograft made from the common tendon of the semitendinous and gracilis muscles. The analysis includes the original articles from the PubMed, Google Scholar, eLibrary, Scopus and Web of Science search systems. The key words for the search included (“peroneus longus tendon” or “fibularis longus tendon”) and (“anterior cruciate ligament reconstruction” or “ACL reconstruction”). In the Russian data bases, the same terms were used. From the articles found, the following parameters were extracted: the evaluation of the functional results using the Tegner–Lysholm scale and the questionnaire for subjective assessment of the status among the patients with various knee joint injuries — IKDC (International Knee Documentation Committee); the evaluation of the mean diameter of the autotransplant; the instability of the knee joint; as well as the possible complications; the evaluation of the functions in the ankle joint and the foot using the AOFAS (American Orthopaedic Foot and Ankle Society) and FADI (Foot and Ankle Disability Index) scales. These parameters were used for evaluating the clinical research works on using the autograft made from the long peroneal muscle tendon for the reconstruction of the anterior cruciate ligament. The authors have analyzed the treatment results in 2322 patients which underwent anterior cruciate ligament plastics using the long peroneal muscle tendon (n=1660) and the semitendinous muscle tendon (n=662) autotransplants. The parameters of the postoperative status according to the AOFAS and FADI scales for the long peroneal muscle tendon were 96.47±2.71 and 97.72±2.58, respectively, which does not differ from the uninjured side (p 0.05). The best IKDC scale scores were 94.13±4.66 for the long peroneal muscle tendon and 95.12±0.73 for the semitendinous muscle tendon, while the scores of the Tegner–Lysholm scale were 99.15±2.89 and 99.85±0.37, respectively. Thus, the autograft made using the long peroneal muscle tendon is a proper alternative for the reconstruction of the anterior cruciate ligament, for it is located outside the area of the knee joint

Хронические нарушения сознания: клинические рекомендации Общероссийской общественной организации «Федерация анестезиологов и реаниматологов»

Хронические нарушения сознания (ХНС) представляют собой синдромы тяжелого поражения центральной нервной системы, приводящие к длительной грубой инвалидизации и требующие значительных усилий по лечению и реабилитации, которые ложатся на медицинские учреждения и на плечи близких пациентов. ХНС развиваются у пациентов после комы и характеризуются наличием бодрствования при полном или практически полном отсутствии признаков осознанного поведения. К ХНС относятся вегетативное состояние (ВС) и состояние минимального сознания (СМС). Также для описания начальных стадий этих состояний используется термин «продленное нарушение сознания» (ПНС). Отдельно выделяют выход из СМС — состояние, которое формируется по мере восстановления когнитивных функций. Диагностика ХНС основывается на многократном структурированном клиническом осмотре с применением специализированных шкал при условии исключения обратимых причин нарушения сознания. Лечение пациентов с ХНС включает в себя поддержание жизненно важных функций, обеспечение оптимального питания и борьбу с типичными осложнениями и сопутствующими состояниями (пролежни, спастичность, боль, пароксизмальная симпатическая гиперактивность и др.). У пациентов с ХНС должна проводиться реабилитация с участием мультидисциплинарной реабилитационной команды в объеме, который определяется проблемами и возможностями конкретного пациента. Наиболее эффективной реабилитация является при условии ее раннего начала. На данный момент однозначных доказательств эффективности каких-либо специфических методов, направленных на восстановление сознания, не получено; изучается ряд соответствующих фармакологических и нефармакологических вмешательств, обязательным условием применения которых является максимально возможная коррекция соматических проблем пациента. Важную роль в ведении пациентов с ХНС играет вовлечение близких пациента, которые, в свою очередь, нуждаются в получении объективной практической информации о состоянии своего родственника и о направлениях реабилитации, а также в психологической помощи

A Study of Biofeedback Gait Training in Cerebral Stroke Patients in the Early Recovery Phase with Stance Phase as Target Parameter

Walking function disorders are typical for patients after cerebral stroke. Biofeedback technology (BFB) is currently considered effective and promising for training walking function, including in patients after cerebral stroke. Most studies recognize that BFB training is a promising tool for improving walking function; however, the data on the use of highly selective walking parameters for BFB training are very limited. The aim of our study was to investigate the feasibility of using BFB training targeting one of the basic parameters of gait symmetry—stance phase duration—in cerebral stroke patients in the early recovery period. The study included 20 hemiparetic patients in the early recovery period after the first hemispheric ischemic stroke. The control group included 20 healthy subjects. The BFB training and biomechanical analysis of walking (before and after all BFB sessions) were done using an inertial system. The mean number of BFB sessions was nine (from 8 to 11) during the three weeks in clinic. There was not a single negative response to BFB training among the study patients, either during the sessions or later. The spatiotemporal parameters of walking showed the whole syndrome complex of slow walking and typical asymmetry of temporal walking parameters, and did not change significantly as a result of the study therapy. The changes were more significant for the functioning of hip and knee joints. The contralateral hip amplitude returned to the normal range. For the knee joint, the amplitude of the first flexion increased and the value of the amplitude of hyperextension decreased in the middle of the stance phase. Concerning muscle function, the observed significant decrease in the function of m. Gastrocnemius and the hamstring muscles on the paretic side remained without change at the end of the treatment course. We obtained positive dynamics of the biomechanical parameters of walking in patients after the BFB training course. The feasibility and efficacy of their use for targeted correction need further research.</jats:p