Effects of a Passive Back Support Exoskeleton when Lifting and Carrying Lumber Boards.

Passive back support exoskeletons, which support the human trunk using elements like springs and elastic bands, have demonstrated positive results in laboratory-based studies, but have seen significantly less field testing. As an intermediate step between generic lab evaluations and field tests, we conducted a single-session lab evaluation of the HeroWear Apex exoskeleton with mockup construction tasks: 20 adult men (without extensive construction experience) lifted, carried and raised lumber boards (265 cm length, up to 18 kg total load). The exoskeleton significantly reduced mean erector spinae electromyograms, with effect sizes (Cohen's d) ranging from -0.2 to -0.55 - corresponding to reductions of 5-25% relative to noexoskeleton electromyogram values. In asymmetric carrying tasks, the exoskeleton provided more assistance to the more heavily loaded erector spinae muscle. Additionally, in lifting tasks, the exoskeleton decreased trunk/hip flexion/extension range of motion and increased knee range of motion, indicating changes in lifting strategy. These results indicate potential exoskeleton benefits for lumber board carrying and will serve as the basis for further evaluations with workers in the field.Clinical Relevance- This study establishes that a passive back exoskeleton reduces erector spinae electromyograms by 525% when lifting and carrying lumber boards used in construction work.

Automated Classification of Dyadic Conversation Scenarios using Autonomic Nervous System Responses.

Two people's physiological responses become more similar as those people talk or cooperate, a phenomenon called physiological synchrony. The degree of synchrony correlates with conversation engagement and cooperation quality, and could thus be used to characterize interpersonal interaction. In this study, we used a combination of physiological synchrony metrics and pattern recognition algorithms to automatically classify four different dyadic conversation scenarios: two-sided positive conversation, two-sided negative conversation, and two one-sided scenarios. Heart rate, skin conductance, respiration and peripheral skin temperature were measured from 16 dyads in all four scenarios, and individual as well as synchrony features were extracted from them. A two-stage classifier based on stepwise feature selection and linear discriminant analysis achieved a four-class classification accuracy of 75.0% in leave-dyad-out crossvalidation. Removing synchrony features reduced accuracy to 65.6%, indicating that synchrony is informative. In the future, such classification algorithms may be used to, e.g., provide real-time feedback about conversation mood to participants, with applications in areas such as mental health counseling and education. The approach may also generalize to group scenarios and adjacent areas such as cooperation and competition.

Automated Patient-Robot Task Assignment in a Simulated Stochastic Rehabilitation Gym.

Rehabilitation after neurological injury can be provided by robots that help patients perform different exercises. Multiple such robots can be combined in a rehabilitation robot gym to allow multiple patients to perform a diverse range of exercises simultaneously. In pursuit of better multipatient supervision, we aim to develop an automated assignment system that assigns patients to different robots during a training session to maximize their skill development. Our previous work was designed for simplified simulated environments where each patient's skill development is known beforehand. The current work improves upon that work by changing the deterministic environment into a stochastic environment where part of the skill development is random and the assignment system must estimate each patient's predicted skill development using a neural network based on the patient's previous training success rate with that robot. These skill development estimates are used to create patient-robot assignments on a timestep-by-timestep basis to maximize the skill development of the patient group. Results from simplified simulation trials show that the schedules produced by our assignment system outperform multiple baseline schedules (e.g., schedules where patients never switch robots and schedules where patients only switch robots once halfway through the session). Additionally, we discuss how some of our simplifications could be addressed in the future.

Learning Skill Training Schedules From Domain Experts for a Multi-Patient Multi-Robot Rehabilitation Gym.

A robotic gym with multiple rehabilitation robots allows multiple patients to exercise simultaneously under the supervision of a single therapist. The multi-patient training outcome can potentially be improved by dynamically assigning patients to robots based on monitored patient data. In this paper, we present an approach to learn dynamic patient-robot assignment from a domain expert via supervised learning. The dynamic assignment algorithm uses a neural network model to predict assignment priorities between patients. This neural network was trained using a synthetic dataset created in a simulated rehabilitation gym to imitate a domain expert's assignment behavior. The approach is evaluated in three simulated scenarios with different complexities and different expert behaviors meant to achieve different training objectives. Evaluation results show that our assignment algorithm imitates the expert's behavior with mean accuracies ranging from 75.4% to 84.5% across scenarios and significantly outperforms three baseline assignment methods with respect to mean skill gain. Our approach solves simplified patient training scheduling problems without complete knowledge about the patient skill acquisition dynamics and leverages human knowledge to learn automated assignment policies.

Effects of the Auxivo CarrySuit occupational exoskeleton when carrying front and side loads on a treadmill.

Low-cost exoskeletons can effectively support workers in physically demanding jobs, but most such exoskeletons have been developed to support repetitive lifting or uncomfortable static postures. Very few low-cost exoskeletons have been designed to support walking while carrying heavy objects, which would be beneficial for jobs such as moving furniture and warehouse work. This paper thus presents a single-session lab evaluation of the Auxivo CarrySuit, a low-cost upper-body exoskeleton designed for carrying objects that would normally be held with the arms. Twenty participants carried four loads (box or two bags, 20 or 40 lb total weight) for 2 min each on a treadmill with and without the CarrySuit. Across all loads, the CarrySuit significantly reduced the mean electromyogram of the middle trapezius (partial eta-squared = 0.74 - from 16.1% to 8.8% of maximum voluntary contraction value) and anterior deltoid (partial eta-squared = 0.26 - from 3.0% to 1.1% of maximum voluntary contraction value) with no corresponding increase in lower back muscle activation. Furthermore, maximum heart rate and Ratings of Perceived Exertion were also reduced by the CarrySuit, and discomfort was shifted from the upper body to the legs. While arm EMG was not measured, it is likely that it was also reduced due to the unloading of the arms. The CarrySuit can thus be considered beneficial in the short term, though longer-term evaluations with actual workers are needed to determine practical benefits.

Automated patient-robot assignment for a robotic rehabilitation gym: a simplified simulation model.

BACKGROUND: A robotic rehabilitation gym can be defined as multiple patients training with multiple robots or passive sensorized devices in a group setting. Recent work with such gyms has shown positive rehabilitation outcomes; furthermore, such gyms allow a single therapist to supervise more than one patient, increasing cost-effectiveness. To allow more effective multipatient supervision in future robotic rehabilitation gyms, we propose an automated system that could dynamically assign patients to different robots within a session in order to optimize rehabilitation outcome. METHODS: As a first step toward implementing a practical patient-robot assignment system, we present a simplified mathematical model of a robotic rehabilitation gym. Mixed-integer nonlinear programming algorithms are used to find effective assignment and training solutions for multiple evaluation scenarios involving different numbers of patients and robots (5 patients and 5 robots, 6 patients and 5 robots, 5 patients and 7 robots), different training durations (7 or 12 time steps) and different complexity levels (whether different patients have different skill acquisition curves, whether robots have exit times associated with them). In all cases, the goal is to maximize total skill gain across all patients and skills within a session. RESULTS: Analyses of variance across different scenarios show that disjunctive and time-indexed optimization models significantly outperform two baseline schedules: staying on one robot throughout a session and switching robots halfway through a session. The disjunctive model results in higher skill gain than the time-indexed model in the given scenarios, and the optimization duration increases as the number of patients, robots and time steps increases. Additionally, we discuss how different model simplifications (e.g., perfectly known and predictable patient skill level) could be addressed in the future and how such software may eventually be used in practice. CONCLUSIONS: Though it involves unrealistically simple scenarios, our study shows that intelligently moving patients between different rehabilitation robots can improve overall skill acquisition in a multi-patient multi-robot environment. While robotic rehabilitation gyms are not yet commonplace in clinical practice, prototypes of them already exist, and our study presents a way to use intelligent decision support to potentially enable more efficient delivery of technologically aided rehabilitation.

Learning Dynamic Patient-Robot Task Assignment and Scheduling for A Robotic Rehabilitation Gym.

A robotic rehabilitation gym is a setup that allows multiple patients to exercise together using multiple robots. The effectiveness of training in such a group setting could be increased by dynamically assigning patients to specific robots. In this simulation study, we develop an automated system that dynamically makes patient-robot assignments based on measured patient performance to achieve optimal group rehabilitation outcome. To solve the dynamic assignment problem, we propose an approach that uses a neural network classifier to predict the assignment priority between two patients for a specific robot given their task success rate on that robot. The priority classifier is trained using assignment demonstrations provided by a domain expert. In the absence of real human data from a robotic gym, we develop a robotic gym simulator and create a synthetic dataset for training the classifier. The simulation results show that our approach makes effective assignments that yield comparable patient training outcomes to those obtained by the domain expert.

Considerations for Voice and Communication Training Software for Transgender and Nonbinary People.

Transgender and gender diverse people often experience voice-gender incongruence, which is inversely correlated with health and quality of life. Such incongruence could be reduced with voice and communication training, but expert-administered training is often inaccessible while self-guided training is difficult and potentially risky. Training could alternatively be provided through software (eg, smartphone apps), but such software is at an early stage. This qualitatively driven mixed-methods study thus includes surveys and interviews with 21 transfeminine, transmasculine and nonbinary people to identify general views of voice and communication training software as well as most desirable features of such software. Participants were positive about the general idea and described ways to effectively implement four critical features: feedback, accountability, automated goal setting, and training characteristics other than pitch. They also discussed optional or undesirable features. These findings may inform development of voice and communication training software, thus improving health and quality of life for gender minorities.

Short-term effects of the Auxivo LiftSuit during lifting and static leaning.

Back support exosuits can support workers in physically demanding jobs by reducing muscle load, which could reduce risk of work-related musculoskeletal disorders. This paper presents a two-session evaluation of a commercial exosuit, the Auxivo LiftSuit 1.1. In session 1, 17 participants performed single repetitions of lifting and static leaning tasks with and without the LiftSuit. In session 2, 10 participants performed 50 box lifting repetitions with and without the LiftSuit. In session 1, the exosuit was considered mildly to moderately helpful, and reduced erector spinae and middle trapezius electromyograms. In session 2, the exosuit was not considered helpful, but reduced the middle trapezius electromyogram and trunk and thigh ranges of motion. These effects are likely due to placement of elastic elements and excessive stiffness at the hips. Overall, the LiftSuit appears suboptimal for long-term use, though elastic elements on the upper back may reduce muscle activation in future exosuit designs.

Localised Langerhans cell histiocytosis of the hypothalamic-pituitary region: case report and literature review.

INTRODUCTION: Langerhans cell histiocytosis (LCH) localised in the hypothalamic-pituitary region (HPR) is very rare, especially in adults. Diabetes insipidus (DI) is considered to be a hallmark of HPR LCH, while anterior pituitary abnormalities are usually seen as consequences of surgery, radiotherapy or chemotherapy. CASE DESCRIPTION: We present a patient with localised HPR LCH with dominant anterior pituitary dysfunction and tumour mass effects but without DI. Seven years after surgery and local radiotherapy, she is stable. Control MRI shows no residual tumour growth and thorough physical examination is still without any signs of disease spread. CONCLUSIONS: Anterior pituitary deficiency can appear without DI and not only as a consequence of LCH treatment. All patients with LCH should be screened for this endocrine abnormality so that appropriate substitution therapy may be provided.

Cervical epidural hematoma: case report.

INTRODUCTION: Cervical epidural hematoma is a rare phenomenon in children. MRI scan of the cervical spine is the method of choice in establishing diagnosis and a quick evacuation of hematoma and de- compression. CASE OUTLINE: We present a case of 11-year-old boy whose lower extremities were paralysed after a trivial injury of the cervical spine which he sustained while playing. Seven days after the injury, severe clinical symptoms appeared, and MRI of the spine showed the presence of cervical epidural hematoma. CONCLUSION: Cervical epidural hematoma in children is very rare. Adequate neurological examination, di- agnostics and urgent surgical intervention are of paramount importance for accomplishing good results. Early and persistent rehabilitation are the condition for achieving maximal recovery.

[Occlusion of maxillary artery in treatment of trigeminal neuralgia].

INTRODUCTION: This paper deals with a treating method of trigeminal neuralgia classified so far as idiopathic neuralgias and treated conservatively. The study was aimed at proving the compression of peripheral branches of N. trigeminus in those patients by vascular elements of A. maxillaris within the bone-ligament space of the scull and the face base. MATERIAL AND METHODS: The study sample consisted of 76 patients having trigeminal neuralgia. The compression was proved by clinical examination, by angiography and electrophysiological investigations. Endovascular occlusion of A. maxillaris is the original method and it was carried out in selected patients. RESULTS: This method was applied in 76 patients. Embolisation was done in 71 patients by using occlusion spiral and gelfoan was used in 3 patients. Externa carotid artery ligation was done in 2 cases. CONCLUSION: The effect of absolute improvement has been achieved and verified by electrophysiological method and subjective assessment of the patients.

[Risk of infection after placement of an extraventricular drainage catheter].

INTRODUCTION: The occurrence of infection after the placement of an extraventricular drainage (EVD) catheter can be a very serious problem in neurosurgery. OBJECTIVE: The aim of this study was to confirm that the use of special catheters with impregnated antibiotics decreased the percentage of infection. METHODS: The prospective study conducted at the Clinic of Neurosurgery in Nis in the period 2006-2009 is presented. Group 1 comprised of 43 patients in whom a commonly used system for EVD was applied. Group 2 comprised of 39 patients in whom the Rifampycin and Clindamycin impregnated EVD catheters were applied (Bactiseal catheters). RESULTS: In Group 1 infection occurred in nine patients, mainly caused by bacteria of Staphylococcus genus. In Group 2 only two patients developed infections caused by Acinetobacter. CONCLUSION: The use of Bactiseal EVD catheters considerably decreased the percentage of infection occurrence with prolonged EVD catheter drainage period.

Complications after angiogram-negative subarachnoid haemorrhage: comparative study of pretruncal and nonpretruncal hemorrhage patients.

INTRODUCTION: Subarachnoid haemorrhages (SAH) of unknown aetiology usually have a mild clinical presentation, favourable outcome and low complication rate. OBJECTIVE: The aim of this study was to analyse the complications in two forms of angiogram-negative spontaneous SAH: pretruncal (PNSAH) and nonpretruncal (NPNSAH). METHODS: The study group involved 18 patients with PNSAH and 16 patients with NPNSAH. CT scan was done within 72 hours from bleeding. All patients underwent four-vessel cerebral angiography. Repeat angiography was performed in five PNSAH and all NPNSAH patients. RESULTS: Twenty-nine patients were in grade I or II of the Hunt-Hess Scale (17 PNSAH and 12 NPNSAH). There was one case of rebleeding (NPNSAH patient), 10 cases of transient acute hydrocephalus (4 PNSAH and 6 NPNSAH). Cerebral vasospasm visualized by angiographies in two NPNSAH patients was local and mild, but was not found in PNSAH patients. Acute electrocardiography changes were found in 19 patients (significantly more frequently in NPNSAH than in PNSAH, 12 and 7 patients, respectively; p = 0.037). CONCLUSION: Cardiac problems following these types of SAH are more frequent than expected, and therefore cardiac monitoring is necessary.

Prognostic significance of intracranial pressure monitoring and intracranial hypertension in severe brain trauma patients.

Since without prospective randomized studies it is not possible to have a clear attitude towards the importance of intracranial pressure monitoring, this study was aimed at examining the prognostic effect of the intracranial pressure monitoring and intracranial pressure oriented therapy in severe brain trauma patients, and at defining optimal intracranial pressure values for starting the treatment. Two groups of patients were treated in the study, one consisted of 32 patients undergoing intracranial pressure monitoring and the second group of 29 patients without intracranial pressure monitoring in the control group. The study was prospective with groups randomized. There were 53% survivals in the intracranial pressure monitored patients and 34% in the control group, with no significant difference in the survival rate between the two groups (chi2=2.11; p=0.15; p>0.05). The average intracranial pressure in the patients with intracranial hypertension who died was 27 mm Hg, while in the patients who survived the average intracranial pressure was significantly lower (Student's t test: t=2.91; p=0.008; p<0.01) and it was 18 mm Hg. We recommend starting intracranial pressure oriented therapy when the patient's intracranial pressure exceeds 18 mmHg during 2 hours of monitoring.

[The incidence and risk factors of ventilator-associated pneumonia in patients with severe traumatic brain injury].

INTRODUCTION: Patients with severe traumatic brain injury are at a risk of developing ventilator-associated pneumonia. The aim of this study was to describe the incidence, etiology, risk factors for development of ventilator-associated pneumonia and outcome in patients with severe traumatic brain injury. MATERIAL AND METHODS: A retrospective study was done in 72 patients with severe traumatic brain injury, who required mechanical ventilation for more than 48 hours. RESULTS: Ventilator-associated pneumonia was found in 31 of 72 (43.06%) patients with severe traumatic brain injury. The risk factors for ventilator-associated pneumonia were: prolonged mechanical ventilation (12.42 vs 4.34 days, p < 0.001), longer stay at intensive care unit (17 vs 5 days, p < 0.001) and chest injury (51.61 vs 19.51%, p < 0.009) compared to patients without ventilator-associated pneumonia. The mortality rate in the patients with ventilator-associated pneumonia was higher (38.71 vs 21.95%, p = 0.12). CONCLUSION: The development of ventilator-associated pneumonia in patients with severe traumatic brain injury led to the increased morbidity due to the prolonged mechanical ventilation, longer stay at intensive care unit and chest injury, but had no effect on mortality.

[The use of recombinant activated factor VII in traumatic intracranial haemorrhage].

INTRODUCTION: A group of patients with craniocerebral injuries received recombinant activated factor VII (rFVIIa) in order to reduce or stop further bleeding in brain tissue. OBJECTIVE: Fundamental objective was to show that the use of rFVIIa can stop intracerebral bleeding and that operative treatment of such patients can be avoided. METHODS: rFVIIa was applied in the group of patients who sustained traumatic brain injuries. The control group was formed retrospectively out of patients with the same pathology previously treated at this clinic throughout 2003 and 2004. It is important to mention that in all patients rFVIIa was applied within first four hours after injury. Coagulation status and GCS were monitored in all patients. RESULTS: The treated patients had different mechanism of injury and pathological substrate of brain tissue. Results were compared with the group of patients who had similar pathological substrate and GCS on admission but did not receive rFVIIa. There were no complications or lethal outcomes recorded in the group of the treated patients. CONCLUSION: Cessation of intracerebral bleeding after timely use of rFVIIa enabled the use of only pharmacological treatment and avoiding operative treatment in some patients. Results were encouraging.

[Recombinant activated factor VII and intraoperative use of cell saver in neurosurgical treatment of arteriovenous malformation].

INTRODUCTION: Arteriovenous (AV) malformation of brain causes abundant intraoperative bleedings, because of increased blood flow, which complicates operative treatment. The use of cell saver for intraoperative salvage of blood and recombinant activated factor VII (rFVIIa) significantly reduces complications during operative treatment. CASE OUTLINE: We present a 29-year old male patient with AV malformation of the 4th degree on Spetzler-Martin scale. Because of the possibility of abundant bleeding, a cell saver (Sequestra 1000 Metronic, USA) was used, and to achieve and control adequate haemostasis, we used rFVIIa. CONCLUSION: The use of cell saver for intraoperative blood salvage and rFVIIa proved successful in operative treatment of AV malformation of 4th degree.

[Recombinant factor VII (NovoSeven) in intraoperative blood saving during neurosurgical treatment of the brain arteriovenous malformation].

BACKGROUND: Cerebral arteriovenous (AV) malformation causes, due to the increased blood flow through a malformation, a massive intraoperative bleeding complicating, so, surgical treatment. The use of intraoperative blood saving apparatus during surgery and a recombinant factor VII-a (NovoSeven) significantly reduce complications during surgical treatment. CASE REPORT: We reported a case of surgical treatment of the patient with AV malformation of IV stage according to the Spetzler-Martin scale, in the brain. Due to a possible heavy bleeding we used a apparatus for intrasurgical blood recovery, Cell Saver, Sequestra 1 000, Medtronic, U.S.A., and recombinant human factor VIIa (rFVIIa--NovoSeven, NovoNordisk, Denmark) to control bleeding and restore an adequate hemostasis. CONCLUSION: The use of an apparatus for intraoperative blood saving, as well as the NovoSeven preparation in the management of AV malformation of IV stage, showed to be successful.