Neurorehabilitation and Neural Repair

Mục tiêu. Nghiên cứu hiệu quả của việc huấn luyện bằng thực tế ảo (VR) trên máy tính cho bàn tay bị liệt nửa người sau đột quỵ, sử dụng hệ thống cung cấp đào tạo tái giáo dục vận động lặp đi lặp lại và tái thu nhận kỹ năng. Phương pháp. Tám đối tượng trong giai đoạn mãn tính sau đột quỵ đã tham gia vào một chương trình kéo dài 3 tuần, sử dụng bàn tay bị liệt nửa người trong một loạt trò chơi máy tính tương tác trong 13 ngày huấn luyện, nghỉ cuối tuần và các kiểm tra trước và sau. Mỗi đối tượng tham gia huấn luyện khoảng 2 đến 2,5 giờ mỗi ngày. Các biện pháp đánh giá bao gồm các thay đổi trong các chỉ số đo trên máy tính về phạm vi chuyển động ngón cái và ngón tay, tốc độ ngón cái và ngón tay, phân khúc (khả năng di chuyển các ngón tay một cách độc lập), sức mạnh ngón cái và ngón tay, Bài kiểm tra Chức năng Tay của Jebsen, và kiểm tra Kinematic nhằm nắm bắt. Kết quả. Nhóm đối tượng đã cải thiện khả năng phân khúc ngón tay, phạm vi chuyển động và tốc độ của ngón cái và ngón tay, duy trì những tiến bộ này trong kiểm tra giữ lại sau một tuần. Chuyển giao các cải thiện này được chứng minh qua sự thay đổi trong Bài kiểm tra Chức năng Tay của Jebsen và sự giảm thiểu thời gian tổng thể từ đỉnh tốc độ tay đến lúc nâng vật từ bàn sau liệu trình trị liệu. Kết luận. Hiện tại, rất khó để cung cấp cường độ thực hành cần thiết cho sự tái tổ chức thần kinh và những thay đổi chức năng sau đột quỵ trong các mô hình cung cấp dịch vụ hiện nay. Các hệ thống bài tập máy tính có thể là một cách để tối ưu hóa thời gian của cả bệnh nhân và bác sĩ lâm sàng. Dữ liệu trong nghiên cứu này bổ sung bằng chứng để đề xuất khám phá các công nghệ mới để tích hợp vào thực hành hiện tại.

Background. There is mounting evidence that the central nervous system utilizes a modular approach for neuromuscular control of walking by activating groups of muscles in units termed muscle synergies. Examination of muscle synergies in clinical populations may provide insights into alteration of neuromuscular control underlying pathological gait patterns. Previous studies utilizing synergy analysis have reported reduced motor control complexity during walking in those with neurological deficits, revealing the potential clinical utility of this approach. Methods. We extracted muscle synergies on a stride-to-stride basis from 20 children with cerebral palsy (CP; Gross Motor Function Classification System levels I-II) and 8 children without CP, allowing the number of synergies to vary for each stride. Similar muscle synergies across all participants and strides were grouped using a k-means clustering and discriminant analysis. Results. In total, 10 clusters representing 10 distinct synergies were found across the 28 individuals. Relative to their total number of synergies deployed during walking, synergies from children with CP were present in a higher number of clusters than in children with typical development (TD), indicating significantly greater stride-to-stride variability. This increased variability was present despite reduced complexity, as measured by the mean number of synergies in each stride. Whereas children with CP demonstrate some novel synergies, they also deploy some of the same muscle synergies as those with TD, although less frequently and with more variability. Conclusion. A stride-by-stride approach to muscle synergy analysis expands its clinical utility and may provide a method to tailor rehabilitation strategies by revealing inconsistent but functional synergies in each child with CP.

Background/objective . Basic science advances in spinal cord injury (SCI) are leading to novel clinical approaches. The authors report a prospective, uncontrolled pilot study of the safety and outcomes of implanting olfactory mucosal autografts (OMA) in 20 patients with chronic, sensorimotor complete or motor complete SCI. Methods. Seven paraplegic and 13 tetraplegic subjects (17 men and 3 women; 19-37 years old) who sustained a traumatic SCI 18 to 189 months previously (mean = 49 months) were enrolled. Preoperative rehabilitation that emphasized lower extremity stepping using either overground walking training or a robotic weight-supported treadmill training was provided for 25 to 39 hours per week for a median of 4 months at 3 sites. No change in ASIA Impairment Scale (AIS) motor scores for the lower extremities or AIS grades of completeness was found. OMAs were transplanted into 1.3- to 4-cm lesions at C4-T12 neurological levels after partial scar removal. Therapy was continued postoperatively. Preoperative and postoperative assessments included AIS scores and classification, electromyography (EMG) of attempted voluntary contractions, somatosensory evoked potentials (SSEP), urodynamic studies with sphincter EMG, spinal cord magnetic resonance imaging (MRI), and otolaryngology and psychology evaluations. The Functional Independence Measure (FIM) and Walking Index for Spinal Cord Injury (WISCI) were obtained in 13 patients. Results. All patients survived and recovered olfaction. One patient was rehospitalized for aseptic meningitis. Minor adverse events occurred in 4 others. The mean duration of follow-up was 27.7 months (range = 12-45 months). By MRI, the lesion site was filled in all patients with no neoplastic overgrowth or syringomyelia. AIS grades improved in 11 of 20 patients, 6 (A → C), 3 (B → C), and 2 (A → B), and declined in 1 (B → A). Improvements included new voluntary EMG responses (15 patients) and SSEPs (4 patients). Scores improved in the FIM and WISCI (13/13 tested), and urodynamic responses improved in 5 patients. Conclusion. OMA is feasible, relatively safe, and possibly beneficial in people with chronic SCI when combined with postoperative rehabilitation. Future controlled trials may need to include a lengthy and intensive rehabilitation arm as a control.

Background. In the chronic stages of moderate-severe traumatic brain injury (TBI), progressive hippocampal volume loss—continuing well after acute neurological insults have resolved—has now been well documented. Previous research in other populations suggests that elevated anxiety symptoms are associated with compromise to the medial temporal lobes. Objective. To examine whether higher anxiety symptoms predict greater hippocampal volume loss in moderate-severe TBI. Methods. We conducted an analysis of prospectively collected, longitudinal behavioral and magnetic resonance imaging (MRI) data from 5 to 12 to 30 months post-injury. Eighty participants were included in the study, with anxiety symptom and MRI data collected at a minimum of 2 time points. Correlational and bivariate latent difference score (with imputation) analyses were used to examine the relationship of Beck Anxiety Inventory scores with hippocampal volume loss, while controlling for depressive symptoms and total brain volume. Results. Analyses revealed that higher anxiety symptoms at 5 and at 12 months following moderate-severe TBI predicted significant later volume loss in the right hippocampal complex and the right hippocampal head. Right hippocampal volume and volume change did not predict subsequent anxiety scores or anxiety change scores. Conclusions. These novel findings implicate anxiety symptoms as a possible predictor of progressive hippocampal volume loss in the chronic stages of moderate-severe TBI.

Objective. The aim of the study was to present a systematic review of studies that investigate the effects of robot-assisted therapy on motor and functional recovery in patients with stroke. Methods. A database of articles published up to October 2006 was compiled using the following Medline key words: cerebral vascular accident, cerebral vascular disorders, stroke, paresis, hemiplegia, upper extremity, arm, and robot. References listed in relevant publications were also screened. Studies that satisfied the following selection criteria were included: (1) patients were diagnosed with cerebral vascular accident; (2) effects of robot-assisted therapy for the upper limb were investigated; (3) the outcome was measured in terms of motor and/or functional recovery of the upper paretic limb; and (4) the study was a randomized clinical trial (RCT). For each outcome measure, the estimated effect size (ES) and the summary effect size (SES) expressed in standard deviation units (SDU) were calculated for motor recovery and functional ability (activities of daily living [ADLs]) using fixed and random effect models. Ten studies, involving 218 patients, were included in the synthesis. Their methodological quality ranged from 4 to 8 on a (maximum) 10-point scale. Results. Meta-analysis showed a nonsignificant heterogeneous SES in terms of upper limb motor recovery. Sensitivity analysis of studies involving only shoulder-elbow robotics subsequently demonstrated a significant homogeneous SES for motor recovery of the upper paretic limb. No significant SES was observed for functional ability (ADL). Conclusion. As a result of marked heterogeneity in studies between distal and proximal arm robotics, no overall significant effect in favor of robot-assisted therapy was found in the present meta-analysis. However, subsequent sensitivity analysis showed a significant improvement in upper limb motor function after stroke for upper arm robotics. No significant improvement was found in ADL function. However, the administered ADL scales in the reviewed studies fail to adequately reflect recovery of the paretic upper limb, whereas valid instruments that measure outcome of dexterity of the paretic arm and hand are mostly absent in selected studies. Future research into the effects of robot-assisted therapy should therefore distinguish between upper and lower robotics arm training and concentrate on kinematical analysis to differentiate between genuine upper limb motor recovery and functional recovery due to compensation strategies by proximal control of the trunk and upper limb.

Background and Objective. Tinnitus is the perception of a phantom sound. The aim of this study was to compare current intensity (center anode 1 mA and 2 mA), duration (10 minutes and 20 minutes), and location (left temporoparietal area [LTA] and dorsolateral prefrontal cortex [DLPFC]) using 4 × 1 high-definition transcranial direct current stimulation (HD-tDCS) for tinnitus reduction. Methods. Twenty-seven participants with chronic tinnitus (>2 years) and mean age of 53.5 years underwent 2 sessions of HD-tDCS of the LTA and DLPFC in a randomized order with a 1 week gap between site of stimulation. During each session, a combination of 4 different settings were used in increasing dose (1 mA, 10 minutes; 1 mA, 20 minutes; 2 mA, 10 minutes; and 2 mA, 20 minutes). The impact of different settings on tinnitus loudness and annoyance was documented. Results. Twenty-one participants (77.78%) reported a minimum of 1 point reduction on tinnitus loudness or annoyance scales. There were significant changes in loudness and annoyance for duration of stimulation, F(1, 26) = 10.08, P < .005, and current intensity, F(1, 26) = 14.24, P = .001. There was no interaction between the location, intensity, and duration of stimulation. Higher intensity (2 mA) and longer duration (20 minutes) of stimulation were more effective. Conclusions. A current intensity of 2 mA for 20-minute duration was the most effective setting used for tinnitus relief. The stimulation of the LTA and DLPFC were equally effective for suppressing tinnitus loudness and annoyance.

This study examines the potential of using mental practice (MP) to promote the learning of 2 mobility tasks in persons with stroke. Twelve patients were trained with MP to increase the loading of the affected limb while standing up from a chair and sitting down. Vertical forces were recorded using force plates under each foot and the chair. Changes in the loading of the affected limb and in task duration, immediately after 1 training session and 24 h later, served as outcomes. After training, the loading of the affected limb had increased {P < 0.001) during standing up (16.2%) and sitting down (17.9%), and the improvement remained significant 24 h later, indicating a learning effect. In contrast, the duration of the performance did not change with training. The results indicate that, in the early stage of learning with MP, changes in limb-loading strategies are a more sensitive measure of performance than is speed.

Objective: The purpose of this study was to investigate anosognosia for hemiple gia (AHP) in the rehabilitation phase after onset of stroke. Methods: Forty-six hemi plegic stroke patients, 29 with right hemisphere damage (RHD) and 17 with left hemi sphere damage (LHD) were evaluated ∼1 month after onset of stroke. Anosognosia was evaluated with an implicit measure designed to assess anosognosic behaviors (choosing between unimanual and bimanual tasks), in addition to a traditional ex plicit verbal measure. Results: AHP was found m 28% of the RHD and 24% of the LHD group. The majority of patients with AHP in the RHD group had large lesions involving the frontal, parietal, or temporal lobes and had coexisting sensory deficits and unilateral spatial neglect, whereas the LHD patients with AHP had predominantly small subcortical lesions and no sensory or attentional deficits. The functional out comes of AHP patients in both hemisphere groups revealed their inability to retain safety measures at discharge from rehabilitation (p < 0.036) and their need for assis tance in basic and instrumental activities of daily living at follow-up. Conclusions: AHP presents a significant risk for negative functional outcome in stroke rehabilita tion. The underlying mechanisms of AHP may be different for left and right hemi sphere patients, therefore requiring different intervention approaches. Key Words: Anosognosia—Cerebrovascular accident—Rehabilitation outcome.

Objective. To examine (1) if serological or cerebrospinal fluid (CSF) biomarkers can be used as diagnostic and/or prognostic tools in patients with spinal cord injury (SCI) and (2) if literature provides recommendations regarding timing and source of biomarker evaluation. Data Sources. A systematic literature search to identify studies reporting on diagnostic and prognostic blood and/or CSF biomarkers in SCI was conducted in PubMed/MEDLINE, CINAHL, Science Direct, The Cochrane Library, ISI Web of Science, and PEDro. Study Selection. Clinical trials, cohort, and pilot studies on patients with traumatic SCI investigating at least one blood or CSF biomarker were included. Following systematic screening, 19 articles were included in the final analysis. PRISMA guidelines were followed to conduct this review. Data Extraction. Independent extraction of articles was completed by 2 authors using predefined inclusion criteria and study quality indicators. Data Synthesis. Nineteen studies published between 2002 and April 2019 with 1596 patients were included in the systematic review. In 14 studies, blood biomarkers were measured, 4 studies investigated CSF biomarkers, and 1 study used both blood and CSF samples. Conclusions. Serum/CSF concentrations of several biomarkers (S100b, IL-6, GFAP, NSE, tau, TNF-α, IL-8, MCP-1, pNF-H, and IP-10) following SCI are highly time dependent and related to injury severity. Future studies need to validate these markers as true biomarkers and should control for secondary complications associated with SCI. A deeper understanding of secondary pathophysiological events after SCI and their effect on biomarker dynamics may improve their clinical significance as surrogate parameters in future clinical studies.

Objectives. This study aimed to establish the minimal detectable change (MDC) and clinically important differences (CID) of the Wolf Motor Function Test (WMFT) in patients with stroke, and to assess the proportions of patients' change scores exceeding the MDC and CID after stroke rehabilitation. Methods. A total of 57 patients received 1 of the 3 treatments for 3 weeks and underwent clinical assessments before and after treatment. The MDC, at 90% confidence (MDC ₉₀), was calculated from the standard error of measurement to indicate a real change for individual patients. Anchor-based and distribution-based approaches were used to triangulate the values of minimal CID. The percentages of patients exceeding the MDC and minimal CID were also examined. Results. The MDC₉₀ of the WMFT was 4.36 for the performance time (WMFT time) and 0.37 for the functional ability scale (WMFT FAS). The minimal CID ranged from 1.5 to 2 seconds on the WMFT time and from 0.2 to 0.4 points on the WMFT FAS. The MDC and CID proportions ranged from 14% to 30% on the WMFT time and from 39% to 65% on the WMFT FAS, respectively. Conclusions. The change score of an individual patient has to reach 4.36 and 0.37 on the WMFT time and WMFT FAS to indicate a real change. The mean change scores of a stroke group on the WMFT time and WMFT FAS should achieve 1.5 to 2 seconds and 0.2 to 0.4 points to be regarded as clinically important changes. Furthermore, the WMFT FAS may be more responsive than the WMFT time based on the results of proportions exceeding the threshold criteria.