Complete SCI Research Articles

OIDA: An optimal interval detection algorithm for automatized determination of stimulation patterns for FES-Cycling in individuals with SCI

BackgroundFES-Cycling is an exciting recreational activity, which allows certain individuals after spinal cord injury or stroke to exercise their paralyzed muscles. The key for a successful application is to activate the right muscles at the right time.MethodsWhile a stimulation pattern is usually determined empirically, we propose an approach using the torque feedback provided by a commercially available crank power-meter installed on a standard trike modified for FES-Cycling. By analysing the difference between active (with stimulation) and passive (without stimulation) torques along a full pedalling cycle, it is possible to differentiate between contributing and resisting phases for a particular muscle group. In this article we present an algorithm for the detection of optimal stimulation intervals and demonstrate its functionality, bilaterally for the quadriceps and hamstring muscles, in one subject with complete SCI on a home trainer. Stimulation patterns were automatically determined for two sensor input modalities: the crank-angle and a normalized thigh-angle (i.e. cycling phase, measured via inertial measurement units). In contrast to previous studies detecting automatic stimulation intervals on motorised ergo-cycles, our approach does not rely on a constant angular velocity provided by a motor, thus being applicable to the domain of mobile FES-Cycling.ResultsThe algorithm was successfully able to identify stimulation intervals, individually for the subject’s left and right quadriceps and hamstring muscles. Smooth cycling was achieved without further adaptation, for both input signals (i.e. crank-angle and normalized thigh-angle).ConclusionThe automatic determination of stimulation patterns, on basis of the positive net-torque generated during electrical stimulation, can help to reduce the duration of the initial fitting phase and to improve the quality of pedalling during a FES-Cycling session. In contrast to previous works, the presented algorithm does not rely on a constant angular velocity and thus can be effectively implemented into mobile FES-Cycling systems. As each muscle or muscle group is assessed individually, our algorithm can be used to evaluate the efficiency of novel electrode configurations and thus could promote increased performances during FES-Cycling.

Comparison of Various Indices in Identifying Insulin Resistance and Diabetes in Chronic Spinal Cord Injury.

The purpose of this screening and diagnostic study was to examine the accord among indices of glucose metabolism, including the Homeostatic Model Assessment for Insulin Resistance (HOMA), HOMA2, Matsuda Index, Quantitative Insulin-sensitivity Check Index (QUICKI), hemoglobin A1C (HbA1C), and fasting plasma glucose (FPG) against intravenous glucose tolerance test-measured insulin sensitivity (Si) in individuals with chronic motor complete SCI. Persons with chronic (≥12-months post-injury) SCI (n = 29; 79% men; age 42.2 ± 11.4; body mass index 28.6 ± 6.4 kg/m2; C4-T10) were included. Measures were compared using adjusted R2 from linear regression models with Akaike information criterion (AIC, a measure of error). QUICKI had the greatest agreement with Si (adjusted R2 = 0.463, AIC = 91.1, p = 0.0001), followed by HOMA (adjusted R2 = 0.378, AIC = 95.4, p = 0.0008), HOMA2 (adjusted R2 = 0.256, AIC = 99.7, p = 0.0030), and the Matsuda Index (adjusted R2 = 0.356, AIC = 95.5, p = 0.0004). FPG (adjusted R2 = 0.056, AIC = 107.5, p = 0.1799) and HbA1C (adjusted R2 = 0.1, AIC = 106.1, p = 0.0975) had poor agreement with Si. While HbA1C and FPG are commonly used for evaluating disorders of glucose metabolism, QUICKI demonstrates the best accord with Si compared to the other measures.

Newly regenerated axons via scaffolds promote sub-lesional reorganization and motor recovery with epidural electrical stimulation

Here, we report the effect of newly regenerated axons via scaffolds on reorganization of spinal circuitry and restoration of motor functions with epidural electrical stimulation (EES). Motor recovery was evaluated for 7 weeks after spinal transection and following implantation with scaffolds seeded with neurotrophin producing Schwann cell and with rapamycin microspheres. Combined treatment with scaffolds and EES-enabled stepping led to functional improvement compared to groups with scaffold or EES, although, the number of axons across scaffolds was not different between groups. Re-transection through the scaffold at week 6 reduced EES-enabled stepping, still demonstrating better performance compared to the other groups. Greater synaptic reorganization in the presence of regenerated axons was found in group with combined therapy. These findings suggest that newly regenerated axons through cell-containing scaffolds with EES-enabled motor training reorganize the sub-lesional circuitry improving motor recovery, demonstrating that neuroregenerative and neuromodulatory therapies cumulatively enhancing motor function after complete SCI.

Transneuronal delivery of designer cytokines: perspectives for spinal cord injury.

Transneuronal delivery of designer cytokines: perspectives for spinal cord injury.

Buspirone for functional improvement after acute traumatic spinal cord injury: a propensity score-matched cohort study.

Retrospective analysis of treated inpatients compared to expected neurorecovery from a propensity score-matched national database cohort. Evaluate the effectiveness of buspirone on clinical neurorecovery following traumatic SCI when started during acute inpatient rehabilitation. University-based hospital in Boston, USA. Chart review yielded thirty-one individuals with acute, traumatic SCI treated with buspirone during inpatient rehabilitation from 2011-2017. Propensity score matching to a cohort of individuals from the spinal cord injury model systems (SCIMS) national database was completed. Changes in upper extremity motor score (UEMS), lower extremity motor score (LEMS), American Spinal Injury Association Impairment Scale (AIS), neurological level of injury (NLI), and functional impairment measure (FIM) from admission to discharge and discharge to 1 year were computed and compared between matched pairs (buspirone and mean national SCIMs cohort). A local control cohort not treated with buspirone was similarly compared to a matched mean national SCIMs group to identify location-specific effects. From admission to discharge from inpatient rehabilitation, 95% confidence intervals of changes in UEMS (-2.43 to +2.78), LEMS (-1.02 to +6.02), AIS (-0.04 to +0.35), NLI (-0.42 to +1.08), and FIM (-4.42 to +6.40) were not significantly different between those individuals who received buspirone and their propensity-matched SCIMS cohort. Similarly, changes in these metrics were not significantly different at 1-year follow up. Buspirone group individuals with initial clinically complete SCI demonstrated a higher 1-year conversion rate to incomplete injury (6 out of 14; 42.9%) compared to the matched national SCIMS cohort (14 out of 70; 21.2%, p = 0.047) though this was not significantly different from non-buspirone local controls (p = 0.25). Retrospective analysis shows no statistically significant difference in gross markers of neurorecovery following acute traumatic SCI when buspirone is initiated indiscriminately during acute inpatient rehabilitation. In individuals with clinically complete SCI, findings suggest possible increased rates of 1-year conversion to incomplete injury.

Scar tissue removal-activated endogenous neural stem cells aid Taxol-modified collagen scaffolds in repairing chronic long-distance transected spinal cord injury.

Scar tissue removal combined with biomaterial implantation is considered an effective measure to repair chronic transected spinal cord injury (SCI). However, whether more scar tissue removal surgeries could affect the treatment effects of biomaterial implantation still needs to be explored. In this study, we performed the first scar tissue removal surgery in the 3rd month and the second in the 6th month after completely removing 1 cm of spinal tissue in canines. We found that Taxol-modified linear ordered collagen scaffold (LOCS + Taxol) implantation could promote axonal regeneration, neurogenesis, and electrophysiological and functional recovery only in canines at the first scar tissue removal surgery, but not in canines at the second scar tissue removal surgery. Interestingly, we found that more endogenous neural stem cells (NSCs) around the injured site could be activated in canines with the first rather than the second scar tissue removal. Furthermore, we demonstrated that Taxol could promote the neuronal differentiation of NSCs in the myelin inhibition microenvironment through the p38 MAPK signaling pathway in vitro. Therefore, we speculated that endogenous NSC activation by the first scar tissue removal surgery and its further differentiation into neurons induced by Taxol may contribute to functional recovery in canines. Together, LOCS + Taxol implantation in combination with the first scar tissue removal provides a promising therapy for chronic long-distance transected SCI repair with the help of scar tissue removal activated endogenous NSCs.

The Danish Spinal Cord Injury Shoulder (DanSCIS) cohort: methodology and primary results.

Cross-sectional study. To describe the socio-demographics, injury characteristics, prevalence of shoulder and neck symptoms, weekly participation in leisure time physical activity (LTPA) and quality of life (QoL) of individuals with spinal cord injury in Denmark (SCI). Nation-wide community survey, Denmark. Individuals with SCI for >2 years were included from three SCI rehabilitation departments. Questionnaire data regarding socio-demographic details, SCI injury characteristics, medical history, shoulder and neck symptoms, LTPA and QoL were collected. Of 2454 potential participants, 1517 (62%) responded to the survey (mean age = 56.2, SD 16.1, 37% female, 42% tetraplegia, 23% complete SCI, mean time since injury = 16.9, SD 13.5). 75% used some form of assistive mobility device. Responders and non-responders showed no sex or injury type/severity differences. Shoulder and neck symptoms within the past 3 months were reported by 63 and 67% respectively, with 51% reporting shoulder symptoms within the past week. Among those with symptoms, 61% had experienced shoulder symptoms and 56% neck symptoms, for more than 30 days during the previous 3 months. Symptoms often prevented participants from performing their usual activities (due to shoulder symptoms 46%, neck symptoms 41%). A high prevalence of self-reported shoulder and neck symptoms was found, which may limit physical function and social activities. We succeeded in generating the Danish Spinal Cord Injury Shoulder (DanSCIS) dataset, which comprised a substantial proportion of Danish adults with SCI. Future studies using data from this cohort will investigate patterns and associations between shoulder/neck symptoms, use of assistive mobility devices, LTPA and QoL.

Bioinspired Postural Controllers for a Locked-Ankle Exoskeleton Targeting Complete SCI Users.

Several lower-limb exoskeletons enable overcoming obstacles that would impair daily activities of wheelchair users, such as going upstairs. Still, as most of the currently commercialized exoskeletons require the use of crutches, they prevent the user from interacting efficiently with the environment. In a previous study, a bio-inspired controller was developed to allow dynamic standing balance for such exoskeletons. It was however only tested on the device without any user. This work describes and evaluates a new controller that extends this previous one with an online model compensation, and the contribution of the hip joint against strong perturbations. In addition, both controllers are tested with the exoskeleton TWIICE One, worn by a complete spinal cord injury pilot. Their performances are compared by the mean of three tasks: standing quietly, resisting external perturbations, and lifting barbells of increasing weight. The new controller exhibits a similar performance for quiet standing, longer recovery time for dynamic perturbations but better ability to sustain prolonged perturbations, and higher weightlifting capability.

Curbing the Challenges in Recent Treatment Guideline for Early Management of Individuals with Traumatic Spinal Cord Injury: Recommendation for Therapeutic Hypothermia

Background: There has been little prognosis in improving function after a complete spinal lesion. The viewpoint that little can be done to improve motor function after complete SCI seems conceptually and scientifically part of the past. With advance in medicine, better neurological outcome is long expected.
 Objectives: The purpose of this review is to explore the challenges in recent treatment guidelines’ for early management of patient with TSCI and to draw recommendation for Therapeutic hypothermia.
 Methods: We conducted a scoping study review comprising 28 studies (2010 to 2020) to identify and examine the research literature related to challenges’ in recent treatment guidelines’ for early management of patient with TSCI.
 Findings: 28 studies were reviewed. Most cited challenges were surgical timing (26%), followed by controversy on the application of MPS (28.6%). In each of the studies, various challenges of acute stage interventions were outline with poor common standards and recommendations for clinical practices. Surgical decompression (16 papers) was the most cited intervention. Generally, result showed that despite the progress that has been made in the acute management of patients with SCI, neurological outcomes have not improved significantly in recent decades.
 Conclusion: Key early interventions are increasingly being recognized; combined Neuroprotective and neuroregenerative care are probably more effective and they inspire current and future research. We concluded that an evidence based guidelines for TH would help reduce the doom experience around complete SCIs. Thus there is a need to better define the beneficial effect of TH on the injured SCI.

Potential of Combination of Bone Marrow Nucleated and Mesenchymal Stem Cells in Complete Spinal Cord Injury.

Cell-based therapies represent one of the definitive treatment approaches to SCI which, to become a routine clinical application, is marred by several known unknowns. The Bone Marrow Mononuclear Cells (BMMNCs) and Mesenchymal Stem Cells (MSCs) represent the most clinically applied cell types for SCI in humans, with safety established, and to an extent, efficacy reported. In this review, we have analysed the clinical studies performed using BMMNC and MSC for complete SCI separately, and the potential for applying those cells in combination. We have also analysed those factors whose outcome in animal studies of SCI could be evaluated in depth but the clinical outcome cannot be evaluated intrinsically owing to practical difficulties. A combination of these two cell types, BMMNC and MSC, has been proven to be advantageous than applying them separately. Therefore, a thorough evaluation including the rationale and potential implications of applying these two therapies has been presented here, and we hypothesize that such a combination is likely to improvise the outcome of a wholesome approach to spinal cord regeneration after SCI.

Ten-Year Experience With Continuous Low-Frequency Pelvic Somatic Nerves Stimulation for Recovery of Voluntary Walking in People With Chronic Spinal Cord Injury: A Prospective Case Series of 29 Consecutive Patients

ObjectiveThe purpose of this study was to report on long-term effects of low-frequency stimulation of the pelvic somatic nerves in patients with chronic spinal cord injuries who underwent laparoscopic implantation of neuroprosthesis (LION) in the pelvic lumbosacral nerves. DesignObservational case report. SettingTertiary referral unit specialized in advanced gynecologic surgery and neuropelveology. ParticipantsPatients (N=29) with chronic SCI who underwent a LION procedure to the pelvic lower motor neurons for the recovery of standing and walking motion. Our study is not composed of preselected patients but includes patients across the entire range of SCIs: patients with paraplegia, patients with tetraplegia (except for high tetraplegia), patients with complete and incomplete SCIs, and even patients with flaccid or spastic paralysis. InterventionPatients underwent in-body functional electrical stimulation–assisted locomotor training and continuous low-frequency pelvic lumbosacral nerve neuromodulation. Main Outcome MeasuresEvolution of American Spinal Injury Association (ASIA) sensory score, ASIA Lower Extremity Motor Score, and Walking Index. ResultsAll patients with incomplete SCI regained some voluntary control of previously paralyzed muscles after a few months of stimulation training. With a follow-up of 9 years, 20 patients (71.4%) were able to demonstrate an electrically assisted voluntary extension of the knee. Twenty-six patients could get to their feet when the pacemaker was switched on (92.8%). Five patients could walk <10 m (17.85%) at the bar. Nineteen patients (Abbreviated Injury Score [AIS] A: n=8; AIS B: n=9; AIS C: n=2) could walk >10 m (67.8%), 8 of them only at the bar (28.5%) and 11 of them with the aid of crutches or a walker and without braces (40%). ConclusionsThe major finding of our study is that 17 of 25 patients with complete motor chronic SCI (68%) developed enough recovery of supraspinal control of leg movements that voluntary walking became feasible, even though a minimal amount of stimulation may be required.

Clinical effects of intrathecal administration of expanded Wharton jelly mesenchymal stromal cells in patients with chronic complete spinal cord injury: a randomized controlled study

Background aimsSpinal cord injury (SCI) represents a devastating condition leading to severe disability related to motor, sensory and autonomic dysfunction. Stem cell transplantation is considered a potential emerging therapy to stimulate neuroplastic and neuroregenerative processes after SCI. In this clinical trial, the authors investigated the safety and clinical recovery effects of intrathecal infusion of expanded Wharton jelly mesenchymal stromal cells (WJ-MSCs) in chronic complete SCI patients. MethodsThe authors designed a randomized, double-blind, crossover, placebo-controlled, phase 1/2a clinical trial (NCT03003364). Participants were 10 patients (7 males, 3 females, age range, 25–47 years) with chronic complete SCI (American Spinal Injury Association A) at dorsal level (T3-11). Patients were randomly assigned to receive a single dose of intrathecal ex vivo-expanded WJ-MSCs (10 × 106 cells) from human umbilical cord or placebo and were then switched to the other arm at 6 months. Clinical evaluation (American Spinal Injury Association impairment scale motor and sensory score, spasticity, neuropathic pain, electrical perception and pain thresholds), lower limb motor evoked potentials (MEPs) and sensory evoked potentials (SEPs), Spinal Cord Independence Measure and World Health Organization Quality of Life Brief Version were assessed at baseline, 1 month, 3 months and 6 months after each intervention. Urodynamic studies and urinary-specific quality of life (Qualiveen questionnaire) as well as anorectal manometry, functional assessment of bowel dysfunction (Rome III diagnostic questionnaire) and severity of fecal incontinence (Wexner score) were conducted at baseline and at 6 months after each intervention. ResultsIntrathecal transplantation of WJ-MSCs was considered safe, with no significant side effects. Following MSC infusion, the authors found significant improvement in pinprick sensation in the dermatomes below the level of injury compared with placebo. Other clinically relevant effects, such as an increase in bladder maximum capacity and compliance and a decrease in bladder neurogenic hyperactivity and external sphincter dyssynergy, were observed only at the individual level. No changes in motor function, spasticity, MEPs, SEPs, bowel function, quality of life or independence measures were observed. ConclusionsIntrathecal transplantation of human umbilical cord-derived WJ-MSCs is a safe intervention. A single intrathecal infusion of WJ-MSCs in patients with chronic complete SCI induced sensory improvement in the segments adjacent to the injury site.

Influence of the intelligent standing mobile robot on lower extremity physiology of complete spinal cord injury patients

BackgroundSpinal cord injury (SCI) remains a high rate of disability. In order to improve the quality of their lives, the application of robots in rehabilitation is increasing. However, few studies have assessed the applicability and the effect of robots in patients with complete injury. ObjectiveThe current study aims to assess the efficacy of robots training on the lower extremity physiology in complete SCI patients. Methods24 patients were recruited and randomly divided into experimental and control group. The two groups spent the same amount of time on regular training. Besides, a 1-h standing training twice daily was offered to both groups five days per week, for four weeks. The experimental group used robot for standing training, while the control group used standing frame. Before and after the experiment, muscle girth and bone mineral density (BMD) were measured as lower extremity physiology. ResultsThe experimental group showed increased muscle girth differences (left ​= ​0.08 ​± ​0.40 ​cm, right ​= ​0.75 ​± ​0.72 ​cm), while the control group showed decreased girth differences (left ​= ​−0.78 ​± ​0.54 ​cm, right ​= ​−0.56 ​± ​0.54 ​cm). The increases in the experimental group showed significant differences compared with the control group (left, P ​= ​0.0002; right, P ​= ​0.023). Both groups showed decreased BMD. The decreases in the experimental group were significantly smaller than those in the control group. ConclusionsTraining with aid of robots combined with the regular rehabilitation treatment can benefit complete SCI patients, in aspect of postponing amyotrophy of lower extremities and reducing bone loss and osteoporosis.

Effects of arm cranking exercise on muscle oxygenation between active and inactive muscles in people with spinal cord injury

Objective: We investigated the effects of the incremental arm-cranking exercise (ACE) on tissue oxygen saturation (StO2) between active and inactive muscles, and the relationship between peak oxygen uptake (VO2peak) and changes in the StO2 in inactive muscles. Design: Observational study. Setting: Community-based supervised intervention. Participants: The participants were individuals with motor and sensory complete spinal cord injury (complete SCI; n = 8) and motor complete but sensory incomplete SCI (incomplete SCI; n = 8), and able-bodied (AB) individuals (n = 8) matched for age, height, and body mass index. Intervention: The ACE was performed at a rate increasing by 10 watts min−1 until exhaustion. Outcome Measures: VO2peak, heart rate (HR), and StO2. Results: While VO2peak was similar among the groups, peak HR was significantly higher in both SCI groups than in the AB (P < 0.05). In active muscles (biceps brachii), no differences in the StO2 were observed among the groups (P > 0.05). In inactive muscles (vastus lateralis), the StO2 in the AB and the incomplete SCI began to decrease at approximately 40% of the peak work rate; however, they remained unchanged in the complete SCI. The reductions in StO2 in the AB were significantly greater than in the incomplete SCI. Conclusions: These results suggest that sympathetic vasoconstriction occurred in the incomplete SCI and AB, although it did not occur in the complete SCI, probably due to a reduction in sympathetic nerve activity. Sympathetic vasoconstriction in inactive muscles may not contribute to an individual’s VO2peak regardless of their group.

Preserved somatosensory conduction in complete spinal cord injury: Discomplete SCI

ObjectiveSpinal cord injury (SCI) disrupts the communication between brain and body parts innervated from below-injury spinal segments, but rarely results in complete anatomical transection of the spinal cord. The aim of this study was to investigate residual somatosensory conduction in clinically complete SCI, to corroborate the concept of sensory discomplete SCI. MethodsWe used fMRI with a somatosensory protocol in which blinded and randomized tactile and nociceptive stimulation was applied on both legs (below-injury level) and one arm (above-injury level) in eleven participants with chronic complete SCI. The experimental design accounts for possible confounding mechanical (e.g. vibration) and cortico-cortical top-down mechanisms (e.g. attention/expectation). ResultsSomatosensory stimulation on below-level insensate body regions activated the somatotopically corresponding part of the contralateral primary somatosensory cortex in six out of eleven participants. ConclusionsOur results represent afferent-driven cortical activation through preserved somatosensory connections to the brain in a subgroup of participants with clinically complete SCI, i.e. sensory discomplete SCI. SignificanceIdentifying patients with residual somatosensory connections might open the door for new rehabilitative and restorative strategies as well as inform research on SCI-related conditions such as neuropathic pain and spasticity.

A STUDY OF RELATION OF LOWER LIMB SPASTICITY WITH LIPID PROFILE AND FASTING PLASMA GLUCOSE LEVELS IN CHRONIC MOTOR COMPLETE SPINAL CORD INJURY PATIENTS.

Background: Most common cause of spinal cord injury in India is fall from height followed by road accidents which may lead to incomplete or complete disruption of neural signal transmission across and below the level of injury. Spasticity is a common but not an inevitable complication following spinal cord injury.&#x0D; Study Objective: The present study tried to explore the correlation between the lower limb spasticity following spinal cord injury and the metabolic markers.&#x0D; Study design: Hospital-based cross-sectional study.&#x0D; Material and Methods: Fifty patients recruited from Department of Physical Medicine and Rehabilitation, Sawai Man Singh Hospital, Jaipur (Raj.), were categorized into mild (16),moderate (11), and severe (23)spastic groups based on assessment of ankle/knee extensor muscle group spasticity using the modified Ashworth scale. The metabolic profile markers such as Total Cholesterol (TC), Low-density Lipoprotein (LDL), High-Density Lipoprotein (HDL), Triglyceride (TG) and Fasting Plasma Glucose (FPG) were estimated and compared between the three groups.&#x0D; Results: The triglycerides, total cholesterol, low density lipoproteins and the fasting plasma glucose level were significantly negatively correlated with the grading of spasticity in lowerlimbs (P &lt;0.001). The high density lipoproteins level was higher in a severe spastic group as compared to the mild and moderate spastic groups; but this result was statistically non-significant (P=0.14).&#x0D; Conclusion: Spasticity in motor complete SCI may have beneficial effects in preserving glucose homeostasis and defending rise in adiposity, rationalizing the need for its judicious management to maintain the crucial balance between its beneficial and problematic effects.&#x0D; Keywords: Spasticity, Modified Ashworth score, Spinal cord injury, lipid profile, fasting plasma glucose.

Gene expression changes are associated with severe bone loss and deficient fracture callus formation in rats with complete spinal cord injury.

Animal study. To investigate the effects of SCI on bone quality and callus formation. University and hospital-based research center, Ribeirão Preto Medical School, Brazil. Rats sustaining a complete SCI for 10 days received a fracture at the femoral diaphysis and were followed-up for 14 days. Bone callus and contralateral nonfractured tibia were assessed by DXA, µCT, ELISA, histomorphometry, immunohistochemistry, biomechanical test, and gene expression. SCI downregulated osteoblastic-related gene expression in the nonfractured tibias, associated with a twofold increase in osteoclasts and overexpression of RANK/RANKL, which resulted in lower bone mass, impaired microarchitecture, and weaker bones. On day 14 postfracture, we revealed early and increased trabecular formation in the callus of SCI rats, despite a marked 75% decrease in OPG-positive cells, and 41% decrease in density. Furthermore, these calluses showed higher porosity and thinner newly formed trabeculae, leading to lower strength and angle failure. SCI-induced bone loss resulted from increased bone resorption and decreased bone formation. We also evidenced accelerated bone healing in the SCI rats, which may be attributed to the predominant intramembranous ossification. However, the newly formed bone was thinner, less dense, and more porous than those in the non-SCI rats. As a result, these calluses are weaker and tolerate lesser torsion deformation than the controls, which may result in recurrent fractures and characterizes a remarkable feature that may severely impair life quality.

FES-Induced Cycling in Complete SCI: A Simpler Control Method Based on Inertial Sensors.

This article introduces a novel approach for a functional electrical stimulation (FES) controller intended for FES-induced cycling based on inertial measurement units (IMUs). This study aims at simplifying the design of electrical stimulation timing patterns while providing a method that can be adapted to different users and devices. In most of studies and commercial devices, the crank angle is used as an input to trigger stimulation onset. We propose instead to use thigh inclination as the reference information to build stimulation timing patterns. The tilting angles of both thighs are estimated from one inertial sensor located above each knee. An IF–THEN rule algorithm detects, online and automatically, the thigh peak angles in order to start and stop the stimulation of quadriceps muscles, depending on these events. One participant with complete paraplegia was included and was able to propel a recumbent trike using the proposed approach after a very short setting time. This new modality opens the way for a simpler and user-friendly method to automatically design FES-induced cycling stimulation patterns, adapted to clinical use, for multiple bike geometries and user morphologies.

Improving Residual Hand Function in Chronic, Complete SCI with BCI-Enabled Functional Task Practice

To assess the therapeutic value of providing object manipulation practice enhanced by brain-computer interface (BCI)-controlled neuromuscular electrical stimulation (NMES) in chronic, complete tetraplegia.

Methodological considerations for near-infrared spectroscopy to assess mitochondrial capacity after spinal cord injury

Background: Skeletal muscle mitochondrial activity is reduced by ∼ 50–60% after SCI, resulting in impaired energy expenditure, glucose utilization and insulin sensitivity. Near infra-red spectroscopy (NIRS) is a non-invasive tool that can be used to assess mitochondrial capacity. Objectives: (1) Highlight methodological limitations impacting data acquisition and analysis such as subcutaneous adipose tissue (SAT) thickness, movement artifacts, inadequate muscle stimulation, light interference, and ischemic discomfort. (2) Provide technical considerations to improve data acquisition and analysis. This may serve as guidance to other researchers and clinicians using NIRS. Study Design: cross-sectional observational design. Settings: Clinical research medical center. Participants: Sixteen men with 1 > year post motor complete SCI. Methods: NIRS signals were obtained from right vastus lateralis muscle utilizing a portable system. Signals were fit to a mono-exponential curve. Outcome Measures: Rate constant and r 2 values for the fit curve, indirectly measures mitochondrial capacity. Results: Only four participants produced data with accepted rate constants of 0.002–0.013 s−1 and r 2 of 0.71–0.87. Applications of studentized residuals ≥2.5 resulted in sparing data from another four participants with rate constants of 0.010–0.018 s−1and r 2 values ranging from 0.86–0.99. Conclusions: Several limitations may challenge the use of NIRS to assess mitochondrial capacity after SCI. Acknowledging these limitations and applying additional data processing techniques may overcome the discussed limitations and facilitate data sparing.