Blood-stage malaria vaccine candidate RH5.1/Matrix-M in healthy Tanzanian adults and children; an open-label, non-randomised, first-in-human, single-centre, phase 1b trial.

BACKGROUND: A blood-stage Plasmodium falciparum malaria vaccine would provide a second line of defence to complement partially effective or waning immunity conferred by the approved pre-erythrocytic vaccines. RH5.1 is a soluble protein vaccine candidate for blood-stage P falciparum, formulated with Matrix-M adjuvant to assess safety and immunogenicity in a malaria-endemic adult and paediatric population for the first time. METHODS: We did a non-randomised, phase 1b, single-centre, dose-escalation, age de-escalation, first-in-human trial of RH5.1/Matrix-M in Bagamoyo, Tanzania. We recruited healthy adults (aged 18-45 years) and children (aged 5-17 months) to receive the RH5.1/Matrix-M vaccine candidate in the following three-dose regimens: 10 µg RH5.1 at 0, 1, and 2 months (Adults 10M), and the higher dose of 50 µg RH5.1 at 0 and 1 month and 10 µg RH5.1 at 6 months (delayed-fractional third dose regimen; Adults DFx). Children received either 10 µg RH5.1 at 0, 1, and 2 months (Children 10M) or 10 µg RH5.1 at 0, 1, and 6 months (delayed third dose regimen; Children 10D), and were recruited in parallel, followed by children who received the dose-escalation regimen (Children DFx) and children with higher malaria pre-exposure who also received the dose-escalation regimen (High Children DFx). All RH5.1 doses were formulated with 50 µg Matrix-M adjuvant. Primary outcomes for vaccine safety were solicited and unsolicited adverse events after each vaccination, along with any serious adverse events during the study period. The secondary outcome measures for immunogenicity were the concentration and avidity of anti-RH5.1 serum IgG antibodies and their percentage growth inhibition activity (GIA) in vitro, as well as cellular immunogenicity to RH5.1. All participants receiving at least one dose of vaccine were included in the primary analyses. This trial is registered at ClinicalTrials.gov, NCT04318002, and is now complete. FINDINGS: Between Jan 25, 2021, and April 15, 2021, we recruited 12 adults (six [50%] in the Adults 10M group and six [50%] in the Adults DFx group) and 48 children (12 each in the Children 10M, Children 10D, Children DFx, and High Children DFx groups). 57 (95%) of 60 participants completed the vaccination series and 55 (92%) completed 22 months of follow-up following the third vaccination. Vaccinations were well-tolerated across both age groups. There were five serious adverse events involving four child participants during the trial, none of which were deemed related to vaccination. RH5-specific T cell and serum IgG antibody responses were induced by vaccination and purified total IgG showed in vitro GIA against P falciparum. We found similar functional quality (ie, GIA per µg RH5-specific IgG) across all age groups and dosing regimens at 14 days after the final vaccination; the concentration of RH5.1-specific polyclonal IgG required to give 50% GIA was 14·3 µg/mL (95% CI 13·4-15·2). 11 children were vaccinated with the delayed third dose regimen and showed the highest median anti-RH5 serum IgG concentration 14 days following the third vaccination (723 µg/mL [IQR 511-1000]), resulting in all 11 who received the full series showing greater than 60% GIA following dilution of total IgG to 2·5 mg/mL (median 88% [IQR 81-94]). INTERPRETATION: The RH5.1/Matrix-M vaccine candidate shows an acceptable safety and reactogenicity profile in both adults and 5-17-month-old children residing in a malaria-endemic area, with all children in the delayed third dose regimen reaching a level of GIA previously associated with protective outcome against blood-stage P falciparum challenge in non-human primates. These data support onward efficacy assessment of this vaccine candidate against clinical malaria in young African children. FUNDING: The European and Developing Countries Clinical Trials Partnership; the UK Medical Research Council; the UK Department for International Development; the National Institute for Health and Care Research Oxford Biomedical Research Centre; the Division of Intramural Research, National Institute of Allergy and Infectious Diseases; the US Agency for International Development; and the Wellcome Trust.

Cortical Mechanisms Underlying Immersive Interactive Virtual Walking Treatment for Amelioration of Neuropathic Pain after Spinal Cord Injury: Findings from a Preliminary Investigation of Thalamic Inhibitory Function.

BACKGROUND: Neuropathic pain following spinal cord injury (SCI) affects approximately 60% of individuals with SCI. Effective pharmacological and non-pharmacological treatments remain elusive. We recently demonstrated that our immersive virtual reality walking intervention (VRWalk) may be effective for SCI NP. Additionally, we found that SCI NP may result from a decrease in thalamic γ-aminobutyric-acid (GABA), which disturbs central sensorimotor processing. OBJECTIVE: While we identified GABAergic changes associated with SCI NP, a critical outstanding question is whether a decrease in SCI NP generated by our VRWalk intervention causes GABA content to rise. METHOD: A subset of participants (n = 7) of our VRWalk trial underwent magnetic resonance spectroscopy pre- and post-VRWalk intervention to determine if the decrease in SCI NP is associated with an increase in thalamic GABA. RESULTS: The findings revealed a significant increase in thalamic GABA content from pre- to post-VRWalk treatment. CONCLUSION: While the current findings are preliminary and should be interpreted with caution, pre- to post-VRWalk reductions in SCI NP may be mediated by pre- to post-treatment increases in thalamic GABA by targeting and normalizing maladaptive sensorimotor cortex reorganization. Understanding the underlying mechanisms of pain recovery can serve to validate the efficacy of home-based VR walking treatment as a means of managing pain following SCI. Neuromodulatory interventions aimed at increasing thalamic inhibitory function may provide more effective pain relief than currently available treatments.

A novel approach to directly measuring wheel and caster rolling resistance accurately predicts user-wheelchair system-level rolling resistance.

Introduction: Clinical practice guidelines for preservation of upper extremity recommend minimizing wheelchair propulsion forces. Our ability to make quantitative recommendations about the effects of wheelchair configuration changes is limited by system-level tests to measure rolling resistance (RR). We developed a method that directly measures caster and propulsion wheel RR at a component-level. The study purpose is to assess accuracy and consistency of component-level estimates of system-level RR. Methods: The RR of N = 144 simulated unique wheelchair-user systems were estimated using our novel component-level method and compared to system-level RR measured by treadmill drag tests, representing combinations of caster types/diameters, rear wheel types/diameters, loads, and front-rear load distributions. Accuracy was assessed by Bland-Altman limits of agreement (LOA) and consistency by intraclass correlation (ICC). Results: Overall ICC was 0.94, 95% CI [0.91-0.95]. Component-level estimates were systematically lower than system-level (-1.1 N), with LOA +/-1.3 N. RR force differences between methods were constant over the range of test conditions. Conclusion: Component-level estimates of wheelchair-user system RR are accurate and consistent when compared to a system-level test method, evidenced by small absolute LOA and high ICC. Combined with a prior study on precision, this study helps to establish validity for this RR test method.

Effect of Training for an Athletic Challenge on Illness Cognition in Individuals with Chronic Disability: A Prospective Cohort Study.

Illness cognitions (IC) influence how a patient adapts to a chronic disease. The aim was (1) to determine if training for a handcycling mountain time trial (HandbikeBattle) improves IC and (2) to identify factors associated with IC change scores. Persons with a chronic disability (N = 220; including N = 151 with spinal cord disorder) trained 5 months and participated in the time trial. The IC Questionnaire measured helplessness, acceptance, perceived benefits and was assessed before training (T1), after training (T2), and four months after the event (T3). Age, sex, body mass index (BMI), time since injury (TSI), disability characteristics, self-efficacy, mental health (MH) and musculoskeletal pain were obtained at T1. Multilevel regression analyses showed that helplessness decreased (from 11.96 to 11.28, p < 0.01) and perceived benefits increased (from 16.91 to 17.58, p < 0.01) from T1 to T2. For helplessness this decrease persisted during follow-up (11.16 at T3). Changes in helplessness were associated with self-efficacy (p = 0.02), MH (p = 0.02) and lesion completeness (p = 0.02), and were independent of disability type (p = 0.66), lesion level (p = 0.30) and demographics such as sex (p = 0.29) and age (p = 0.67). Training with peers may improve helplessness and perceived benefits in individuals with a chronic disability. Especially individuals with MH problems might benefit from training for an athletic challenge with peers to improve illness cognitions, and ultimately, quality of life.

Longitudinal Median Nerve Ultrasound Changes in Individuals With Spinal Cord Injury and an Age- and Sex-Matched Nondisabled Cohort.

Objectives: To assess the natural history for development of carpal tunnel syndrome (CTS) in persons with acute spinal cord injury (SCI) at 1 year postdischarge from initial rehabilitation and to assess baseline median nerve (MN) cross-sectional area (CSA) above/below 10 mm2 correlates with any longitudinal changes in quantitative ultrasound (US) of the MN. Design: A prospective cohort study of persons with acute SCI evaluated for CTS using quantitative US and compared to a group without SCI (non-SCI). Setting: Academic medical center. Participants: N=69 total (N=34 SCI, N=35 non-SCI). The average age in both groups was 28 and the SCI group included 30 males and 2 females and the non-SCI group included 30 males and 3 females. Interventions: Not applicable. Main Outcome Measures: The primary outcome was the change in quantitative US parameters of the MN, including CSA and grayscale, from baseline to 1-year follow-up in those with SCI and those without SCI. CTS symptomatology and physical exam sum score and US measures for dominant and nondominant arms were considered secondary outcomes. Results: The SCI had darker nerves at baseline (P=.036, nondominant), greater CTS symptoms at follow-up (P≤.036, bilateral), and no differences in all change scores (all P≥.056). Individuals with smaller nerves at baseline had larger increases in nerve size (P=.029, nondominant) vs those with larger nerves. Change in CTS symptoms CSA (nondominant) and nerve echogenicity (dominant) were inversely associated with their respective baseline values (all P≤.045). Conclusions: We observed few differences between the SCI group and the non-SCI control group and between those with smaller vs larger MN. In general, MN pathology changes (CTS symptoms and US variables) over 1 year were more common in the nondominant arm and appear to be a function of MN pathology at enrollment. Individuals with SCI may experience increased CTS symptoms as soon as 1 year after injury.

Association between individual wheelchair skills and fitness in community-dwelling manual wheelchair users with spinal cord injuries.

PURPOSE: Wheelchair skills are a key component to promotion of community participation among persons with spinal cord injury (SCI). The objective of this secondary analysis was to examine the association between individual wheelchair skills from the Wheelchair Skills Test Questionnaire (WST-Q) and fitness among community-dwelling adults with SCI. MATERIALS AND METHODS: Twenty-six adults were recruited to complete the WST-Q and a standard graded aerobic wheelchair exercise test on a motorized treadmill for assessing peak power output (POpeak). RESULTS: Spearman Rho rank-order correlation (ρ) analyses indicated statistically significant correlations between POpeak and six basic (ρ = 0.41-0.57), eight intermediate (ρ = 0.44-0.59), and nine advanced (ρ = 0.42-0.80) WST-Q skill scores. After controlling for sex and injury level (Partial Spearman Rho rank order) significant correlations persisted for four advanced skills (i.e., descends high curb, turns in place in wheelie position, descends steep incline in wheelie position, descends high curb in wheelie position; ρ = 0.46-0.59) and one additional skill (i.e., ascends high curb ρ = 0.51). CONCLUSIONS: More advanced wheelchair skills are significantly associated with fitness in persons with SCI. The directionality of the skills-fitness relationship, specifically whether wheelchair skills facilitate greater fitness or fitness is a prerequisite for certain wheelchair skills needs to be determined in future, larger studies. However, results from this study provide a comprehensive list of wheelchair skills that are associated with fitness that can be directly applied to guide further research and practice promoting community participation among persons with SCI.Implications for RehabilitationSignificant positive associations exist between advanced wheelchair skills (i.e., descends high curb, turns in place in wheelie position, descends steep incline in wheelie position, descends high curb in wheelie position and ascends high curb) and fitness in manual wheelchair users with spinal cord injury (SCI).This study provides a list of skills associated with fitness to guide clinical practice and areas for further rehabilitation research assessing the directionality of the relationship between fitness and wheelchair skills.

Lifestyle physical activity in manual wheelchair users - an overlooked public health opportunity.

Public health guidelines and health promotion efforts have traditionally focused on weekly accumulation of moderate to vigorous physical activity (MVPA) via structured exercise. There has been a recent paradigm shift towards the organic incorporation of MVPA in daily leisure and non-leisure time, termed "Lifestyle Physical Activity" (LPA). However, this paradigm shift and the underlying research has neglected manual wheelchair users (MWCUs) with spinal cord injury (SCI), who could benefit from LPA. This article argues for expanding the LPA paradigm shift into research and health promotion efforts involving MWCUs with SCI. We suggest a working definition of LPA for MWCUs and candidate metrics for quantifying LPA. This is followed by brief overviews of LPA correlates, outcomes/consequences, and interventions and the need for theory based approaches to study these domains. We lastly suggest an approach for mitigating potential negative outcomes of increased LPA in MWCUs and suggest a research agenda.

The Effect of External Power Output and Its Reliability on Propulsion Technique Variables in Wheelchair Users With Spinal Cord Injury.

The purpose of this study was to assess 1) how treadmill slope variance affected external power output (PO) and propulsion technique reliability; and 2) how PO is associated with propulsion technique. Eighteen individuals with spinal cord injury performed two wheelchair treadmill exercise blocks (0% and 1% treadmill slope, standardized velocity) twice on two separate days. PO, velocity, and 14 propulsion technique variables were measured. In a follow-up study, N = 29 performed wheelchair treadmill drag tests. Target and actual slope were documented and PO, intraclass correlation coefficients (ICC) and smallest detectable differences (SDD) were calculated. Within and between visits, the reliability study ICCs were perfect for velocity (1.0), weak for PO (0.33-0.46), and acceptable (>0.70) for five (0% slope) and 10 (1% slope) propulsion technique variables, resulting in SDDs of 35-196%. Measured PO explained 56-90% of the variance in key propulsion technique variables. In the follow-up, PO ICCs were weak (0.43) and SDDs high. Bias between target and actual slope appeared random. In conclusion, PO variability accounts for 50-90% of the variability in propulsion technique variables when speed and wheelchair set-up are held constant. Therefore, small differences in PO between interventions could mask the effect of the interventions on propulsion technique.

Effectiveness of Group Wheelchair Maintenance Training for People with Spinal Cord Injury: A Randomized Controlled Trial.

OBJECTIVE: To assess the effectiveness of group wheelchair maintenance training and investigate participant characteristics associated with responsiveness to training. DESIGN: Randomized controlled trial with an immediate group and a waitlist control group (WLCG) who received the intervention after a 6-month delay. SETTING: Four Spinal Cord Injury Model Systems Centers. PARTICIPANTS: Manual (MWC; n=80) and power wheelchair (PWC; n=67) users with spinal cord injury (N=147). INTERVENTIONS: Two 90-minute structured wheelchair maintenance training program classes with 12-20 people per class and separate classes for MWC and PWC users. Each class included in-person hands-on demonstrations and practice of wheelchair maintenance. MAIN OUTCOME MEASURES: Separate analysis was completed for MWC and PWC users using the Wheelchair Maintenance Training Questionnaire (WMT-Q) capacity (ability to complete), performance (frequency of completion) and knowledge at baseline, 1 month, 6 months, 6 months pretraining (WLCG only), and 1 year (immediate only). RESULTS: After the intervention, participants in both the immediate and WLCG improved in maintenance capacity (MWC and PWC, P<.001) and performance (MWC and PWC, P<.001) with training. Only PWC users improved knowledge of wheelchair maintenance (P<.001). For both WLCGs (MWC and PWC), there was no difference between the 6-month pretraining time point and baseline. MWC users who responded to training had lower WMT-Q scores for all domains, whereas this was only the case for knowledge for PWC users. CONCLUSIONS: Group wheelchair skills training is effective at improving capacity to complete maintenance and performance of maintenance activities for MWC and PWC users, even in a cohort of experienced wheelchair users. For MWC users, improvements were tied to lower WMT-Q scores at baseline, whereas PWC users improved in capacity and performance independent of baseline score. Delivering this training in a structured group format has a lower cost, which might improve adoption into clinical practice.

Using remote learning to teach clinicians manual wheelchair skills: a cohort study with pre- vs post-training comparisons.

PURPOSE: To test the hypothesis that remote learning to teach clinicians manual wheelchair skills is efficacious. MATERIALS AND METHODS: A convenience sample of therapists (physical and occupational) and students were enrolled in pairs in a cohort study with pre- versus post-training comparisons. The intervention was a hybrid of self-study and hands-on practice paired with remote feedback for ten intermediate and advanced manual wheelchair skills. Participants practiced with self-selected frequency and duration, uploading a session log and video(s) to an online platform. A remote trainer provided asynchronous feedback prior to the next practice session. Capacity and confidence in completing the ten skills were evaluated using the Wheelchair Skills Test Questionnaire (WST-Q). Knowledge of wheelchair skills training and motor learning was assessed using a 62-item Knowledge Test. Secondary outcome measures included skill achievement, as confirmed by submitted video recordings, and participant feedback about the training. RESULTS: Across 41participants, scores were higher at follow-up compared to baseline for WST-Q capacity (73.9 ± 19.1 vs 16.8 ± 15.6, p < 0.001), WST-Q confidence (80.1 ± 12.2 vs 47.6 ± 18.2, p = 0.003) and knowledge (70.8 ± 7.5 vs 67.0 ± 5.4, p = 0.004). CONCLUSIONS: Remote learning can increase wheelchair skills capacity and confidence as well as knowledge about such training and assessment. This model should be further investigated as a delivery method for training rehabilitation professionals. CLINICAL TRIAL REGISTRATION NUMBER: NCT01807728.Implications for rehabilitationWheelchair skills training is one of the 8 steps of wheelchair provision as outlined by the World Health Organization.Wheelchair skills are not a core part of most clinical curriculums and many clinicians cite a lack of resources and uncertainty on how to implement wheelchair skills training into practice as major barriers to providing such training.Remote learning offers the benefits of structured wheelchair skills training with expert feedback on an individual's own schedule that is not afforded by one-day "bootcamp"-type courses or on-the-job training, which are how many clinicians currently learn wheelchair skills.In a sample of physical and occupational therapists and students, remote learning was effective at increasing capacity and confidence to perform manual wheelchair skills as well as knowledge of wheelchair training.

Efficacy of a Remote Train-the-Trainer Model for Wheelchair Skills Training Administered by Clinicians: A Cohort Study With Pre- vs Posttraining Comparisons.

OBJECTIVE: To test the hypotheses that remote training improves trainer confidence and when these trainers train others the capacity and confidence of the trainees improves. DESIGN: Cohort study with pre- vs posttraining comparisons. SETTING: Four spinal cord injury model systems centers. PARTICIPANTS: Convenience sample of 7 clinician trainers and 19 able-bodied trainees (N=26). INTERVENTIONS: Part 1 focused on trainer skill acquisition with self-study of the Wheelchair Skills Program Manual and instructional videos focused on motor learning, spotting, and 10 intermediate and advanced wheelchair skills. Trainers practiced in pairs, receiving asynchronous feedback on video recordings from a remote instructor. Part 2 included additional video modules targeted at "how to" assess and train others in 4 wheelchair skills: gets over obstacle, ascends low curb, ascends high curb with caregiver assistance, and performs stationary wheelie. Upon completion, the trainers each provided 1:1 in-person training for 2-3 trainees. MAIN OUTCOME MEASURES: Trainer confidence was assessed using the Self-Efficacy on Assessing, Training, and Spotting Test for Manual Wheelchairs. Trainee capacity ("Can you do it?") and confidence ("How confident are you?") were evaluated using the Wheelchair Skills Test Questionnaire (WST-Q). RESULTS: Trainer confidence increased for assessment (P=.003) and training (P=.002) but not spotting (P=.056). Trainee 4-item median (interquartile range) WST-Q scores significantly increased with training for capacity (13% [6-31] to 88% [75-88], P<.001) and confidence (13% [0-31] to 88% [81-100], P<.001). CONCLUSIONS: Remote training improves trainers' confidence with respect to wheelchair skills testing and training and the wheelchair skills capacity and confidence of their trainees.

Sociodemographic characteristics associated with physical activity barrier perception among manual wheelchair users.

BACKGROUND: Individuals with disabilities are sub-optimally active and at increased risk for chronic diseases. Limited knowledge exists about how differences among wheelchair-dependent individuals may affect their perception of physical activity barriers. OBJECTIVE: We examined whether the perception of physical activity barriers are associated with wheelchair user sociodemographic characteristics. METHODS: Danish manual wheelchair users (MWCUs) (N = 181; 52.5% females, mean ± SD: age 48 ± 14 yrs) completed the 'Barriers to Physical Activity Questionnaire for People with Mobility Impairments' (BPAQ-MI) online. The BPAQ-MI queries physical activity barriers in four domains (intrapersonal, interpersonal, organizational, and community) and eight subdomains. Participant characteristics evaluated as potentially associated with physical activity barriers included age, sex, years in chair, body mass index (BMI), spinal cord injury (SCI) (if any), education, employment, and resident city size. Simple linear regression (step 1) and multiple regression models (step 2) were created to assess associations between MWCU characteristics and barriers. RESULTS: Multiple regression models revealed that MWCUs who were obese, who did not complete high school, or were unemployed rated physical activity barriers higher across several subdomains (all r2≤0.226, p<0.05). Resident city size was associated with safety subdomain barrier impact (r2=0.039, p<0.05). Sex, age, years in chair and SCI were not associated with any barrier domains (all p ≥ 0.064). CONCLUSIONS: Our results provide new evidence that MWCUs with BMI ≥30; who are not employed; or who only have completed high school, may need special consideration and resources to overcome distinct physical activity barriers. Behavioral strategies and interventions focusing on reducing physical activity barriers should be tailored to the individuals above.

Development and deployment of an at-home strength and conditioning program to support a phase I trial in persons with chronic spinal cord injury.

STUDY DESIGN: Nonrandomized clinical trial (NCT02354625). OBJECTIVES: As a part of a Phase I clinical trial to assess the safety of autologous human Schwann cells (ahSC) in persons with chronic spinal cord injury (SCI), participants engaged in a multimodal conditioning program pre- and post-ahSC transplantation. The program included a home-based strength and endurance training program to prevent lack of fitness and posttransplantation detraining from confounding potential ahSC therapeutic effects. This paper describes development, deployment, outcomes, and challenges of the home-based training program. SETTING: University-based laboratory. METHODS: Development phase: two men with paraplegia completed an 8-week laboratory-based 'test' of the home-based program. Deployment phase: the first four (two males, two females) participant cohort of the ahSC trial completed the program at home for 12 weeks pre and 20 weeks post ahSC transplant. RESULTS: Development phase: both participants improved their peak aerobic capacity (VO2peak) (≥17%), peak power output (POpeak) (≥8%), and time to exhaustion (TTE) (≥7%). Deployment phase: pretransplant training minimally increased fitness in the two male participants (≥6% POpeak and ≥9% TTE). The two women had no POpeak changes and slight TTE changes (+2.6 and -1.2%, respectively.) All four participants detrained during the posttransplant recovery period. After posttransplant retraining, all four participants increased TTE (4-24%), three increased VO2peak (≥11%), and two increased POpeak (≥7%). CONCLUSIONS: Home-based strength and condition programs can be effective and successfully included in therapeutic SCI trials. However, development of these programs requires substantial content knowledge and experience.

Good association between sprint power and aerobic peak power during asynchronuous arm-crank exercise in people with spinal cord injury.

PURPOSE: To (1) investigate the association between sprint power and aerobic power output (POpeakGXT) during a graded peak exercise test (GXT); and (2) validate the prediction models of POpeakGXT based on sprint power and personal and lesion characteristics. MATERIALS AND METHODS: Wheelchair users with tetraplegia (N = 35) and paraplegia (N = 58) performed a 30 s-Wingate test and GXT on an asynchronous arm-crank ergometer. Data were split into samples to develop and validate the model. Sprint power (POmeanWingate and POpeakWingate, respectively) and POpeakGXT were determined. Regression analyses were performed to develop POpeakGXT prediction models. Candidate independent variables included POmeanWingate or POpeakWingate, age (years), sex, body mass (kg) or BMI (kg/m2), time since injury (TSI, years) and lesion level (tetraplegia/paraplegia). The best model was validated by comparing the predicted POpeakGXT with measured POpeakGXT. RESULTS: The best model (R2 = 0.76) to predict POpeakGXT included POmeanWingate, BMI and all other independent variables. No significant difference was found between measured (68 ± 35 W) and predicted POpeakGXT (68 ± 30 W, p = 0.97). The ICC was excellent (0.89 with 95% confidence intervals: 0.75-0.95). The 95% limits of agreement for the Bland-Altman plots were wide (-30 to 31 W). CONCLUSIONS: Strong associations were found between POmeanWingate and POpeakGXT. Although relative agreement was excellent, absolute agreement was low. Implications for rehabilitation There is a strong relationship between peak aerobic power output and sprint power output, both tested on an arm-crank ergometer, in people with spinal cord injury. A prediction model for peak aerobic power output, based on sprint power output and personal and lesion characteristics, showed a high explained variance. The predictive model can give a guideline for choosing the right graded exercise test protocol but should be used with caution.

Physical Activity Barriers in Danish Manual Wheelchair Users: A Cross-sectional Study.

OBJECTIVE: To identify physical activity barrier prevalence and severity among manual wheelchair users (MWCUs) and test whether barrier impact is associated with self-reported physical activity level (PAL). DESIGN: Cross-sectional survey. The Barriers to Physical Activity Questionnaire for People with Mobility Impairments (BPAQ-MI) was translated from English to Danish and administered online. The BPAQ-MI includes barriers within 4 domains and 8 subdomains and queries if an item hindered physical activity participation in the last 3 months (yes/no). If "yes," participants graded barrier severity from very small (1) to very big (5). Barrier impact scores were summed within and across domains. SETTING: General community. PARTICIPANTS: Danish MWCUs (N=181; 52.5% female, mean age, 48±14y.). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: PAL was rated from not active (1) to extremely active (10). Individual barrier prevalence (frequency, %) and severity (median [interquartile range]) was computed. Unadjusted (Spearman rank correlations, domains, subdomains) and adjusted (multivariate linear regression, subdomains) associations between PAL and barrier impact were computed. RESULTS: The 5 most prevalent barriers were reported by ≥49.6% of participants (2 intrapersonal and 3 community). The 5 most severe barriers all had a median of 5 (1 organizational and 4 community). Unadjusted analysis showed that PAL was inversely associated with total intrapersonal (r=-0.487, P<.01) and overall (r=-0.241, P<.01) impact and the intrapersonal "health" (r=-0.477, P<.01) and "beliefs/attitudes"(r=-0.307, P<.01) subdomains. Adjustment for shared variance revealed only the "health" subdomain impact score was independently associated with PAL (P<.001). CONCLUSIONS: Intrapersonal barriers were highly prevalent. Health-related barriers were inversely related to PAL. When organizational and community barriers were present, they were rated as particularly severe. These results provide novel information that can guide the design of future interventions aiming to increase MWCUs PALs.

A Primary Care Provider's Guide to Wheelchair Prescription for Persons With Spinal Cord Injury.

The wheelchair is an essential tool for individuals with spinal cord injury (SCI). When the capacity and fit of a wheelchair is matched to the needs and abilities of an individual with SCI, health, function, community participation, and quality of life are maximized. Throughout an individual's life, function and health status can decline (or improve), necessitating a new wheelchair and/or seating components (eg, cushions and backrests). Additionally, a patient's current wheelchair may be identified as a factor contributing to a health concern or functional deficit, again necessitating wheelchair adjustments. Primary care physicians often manage the complex and lifelong medical needs of individuals with SCI and play a key role in wheelchair evaluation and prescription. This article provides a broad overview of indicators that a new wheelchair is needed, describes the wheelchair prescription process, identifies important team members, reviews the major wheelchair components, and provides guidance to match components to patients' needs and abilities.

Case-Control Study of Ultrasound Evaluation of Acute Median Nerve Response to Upper Extremity Circuit Training in Spinal Cord Injury.

OBJECTIVE: Individuals with spinal cord injury (SCI) often present signs and symptoms of median nerve (MN) pathology. Preclinical signs identification of MN pathology might facilitate early intervention to prevent or delay carpal tunnel syndrome in SCI. We assessed if ultrasound parameters changed in response to upper extremity (UE) circuit training exercise in individuals with paraplegia and able-bodied individuals. DESIGN: Case-control study. PARTICIPANTS: Adults (N=32) with paraplegia (n=16) and age- and sex-matched able-bodied controls (n=16). INTERVENTION: Circuit training exercise. MAIN OUTCOME MEASURES: MN ultrasound evaluation at the pisiform and radius before and after UE exercise. Ultrasound parameters included cross-sectional area (CSA), and gray scale (GS). Data presented as mean ± SD. RESULTS: Pre-exercise CSAs were larger in SCI at the radius (12.0±2.9 vs 9.0±2.1; P=.003), but not the pisiform (9.8±3.1 vs 9.1±1.7; P=.431). There were no statistical differences in MN response to exercise between groups (all P≥.293). Across participants, CSA changes were inversely associated with their pre-exercise values at the pisiform (r=-0.648; P<.001) and the radius (r=-0.366; P=.043). Participants with pre-exercise CSA values ≥10.00 mm2 at the pisiform responded to exercise with decreases in CSA (mean change ± SD, -2.0±1.5; P=.002) and GS (-2.8±6.2; P=.029). Participants with pre-exercise CSA ≤9.99 mm2 at the pisiform responded to exercise with no change in CSA (mean change ± SD, 0.7±2.5; P=.002) and increased GS (3.2±7.2; P=.029). CONCLUSIONS: CSA exercise response was more strongly related to pre-exercise MN values than presence or absence of SCI.

Recovery Off-Kinetics Following Exhaustive Upper Body Exercise in Spinal Cord Injury.

BACKGROUND: People with spinal cord injury (SCI) present with impaired autonomic control when the lesion is above T6. This could lead to delayed cardiorespiratory recovery following vigorous physical activity. OBJECTIVES: To characterize and compare gas exchange off-kinetics following exhaustive exercise in individuals with SCI and an apparently healthy control group. METHODS: Participants were 19 individuals with SCI who presented with the inability to voluntarily lift their legs against gravity (age, 44.6 ± 14.2 years; AIS A, n = 5; AIS B, n = 7; AIS C, n = 7; paraplegia, n = 14; tetraplegia, n = 5) and 10 healthy comparisons (COM; age, 30.5 ± 5.3 years). All participants performed an arm ergometer cardiopulmonary exercise test (aCPET) to volitional exhaustion followed by a 10-minute passive recovery. O2 uptake (V̇o2 ) and CO2 output (V̇co2 ) off-kinetics was examined using a mono-exponential model in which tau off (τoff ) and mean response time (MRT) were determined. The off-kinetics transition constant (Ktoff ) was calculated as ΔV̇o2 /MRT. Student t tests were used to compare SCI versus COM group means. RESULTS: COM had a significantly higher relative peak V̇o2 compared to SCI (1.70 ± 0.55 L/min vs 1.19 ± 0.51 L/min, p = .019). No difference was observed for τoff between the groups, however Ktoff for both V̇o2 and V̇co2 was significantly lower in the SCI compared to the COM group. CONCLUSION: A reduced Ktoff during recovery may suggest inefficiencies in replenishing muscle ATP stores and lactate clearance in these participants with SCI. These findings may contribute to the observed lower cardiorespiratory fitness and greater fatigability typically reported in individuals with SCI.

Relationship between wheelchair skills scores and peak aerobic exercise capacity of manual wheelchair users with spinal cord injury: a cross-sectional study.

Purpose: Although both wheelchair skills and fitness are important and probably inter-related, the extent and nature of the relationship between them are not well understood. The objective of this study was to test the hypothesis that there are significant relationships between wheelchair skills scores and the peak exercise capacity of community-dwelling manual wheelchair users with spinal cord injury.Materials and methods: We studied 26 participants, recording Wheelchair Skills Test Questionnaire scores and peak power output from graded aerobic wheelchair exercise testing on a motorized treadmill.Results: The median Wheelchair Skills Test Questionnaire capacity, confidence, and performance scores were 83.3%, 81.5%, and 76.7% and the median peak power output was 58.2 W. On regression analysis, there were significant relationships between the total Wheelchair Skills Test Questionnaire capacity, confidence, and performance scores and peak power output (R2 0.270-0.709, odds ratios 1.043-1.150, p < 0.05).Conclusions: Significant relationships exist between the wheelchair skills capacity, confidence, and performance scores and the peak exercise capacity of community-dwelling manual wheelchair users with spinal cord injury. These findings suggest that both wheelchair skills training and exercise training may be useful during the rehabilitation of people with spinal cord injury.Implications for rehabilitationModerate positive relationships exist between wheelchair skills capacity and the peak exercise capacity of community-dwelling manual wheelchair users with spinal cord injury.Moderate positive relationships exist between wheelchair skills confidence and the peak exercise capacity of community-dwelling manual wheelchair users with spinal cord injury.Although further research is needed, these findings suggest that clinicians should address both wheelchair skills training and exercise training during the rehabilitation of people with spinal cord injury and not assume that either alone is sufficient.