Enhancing SCI Care: Using Wearable Technologies for Physical Activity, Sleep, and Cardiovascular Health.

Wearable devices have the potential to advance healthcare by enabling real-time monitoring of biobehavioral data and facilitating the management of an individual's health conditions. Individuals living with spinal cord injury (SCI) have impaired motor function, which results in deconditioning and worsening cardiovascular health outcomes. Wearable devices may promote physical activity and allow the monitoring of secondary complications associated with SCI, potentially improving motor function, sleep, and cardiovascular health. However, several challenges remain to optimize the application of wearable technologies within this population. One is striking a balance between research-grade and consumer-grade devices in terms of cost, accessibility, and validity. Additionally, limited literature supports the validity and use of wearable technology in monitoring cardio-autonomic and sleep for individuals with SCI. Future directions include conducting performance evaluations of wearable devices to precisely capture the additional variation in movement and physiological parameters seen in those with SCI. Moreover, efforts to make the devices small, lightweight, and inexpensive for consumer ease of use may impact those with severe motor impairments. Overcoming these challenges holds the potential for wearable devices to help individuals living with SCI receive timely feedback to manage their health conditions and help clinicians gather comprehensive patient health information to aid in diagnosis and treatment.

mHealth-Based Just-in-Time Adaptive Intervention to Improve the Physical Activity Levels of Individuals With Spinal Cord Injury: Protocol for a Randomized Controlled Trial.

BACKGROUND: The lack of regular physical activity (PA) in individuals with spinal cord injury (SCI) in the United States is an ongoing health crisis. Regular PA and exercise-based interventions have been linked with improved outcomes and healthier lifestyles among those with SCI. Providing people with an accurate estimate of their everyday PA level can promote PA. Furthermore, PA tracking can be combined with mobile health technology such as smartphones and smartwatches to provide a just-in-time adaptive intervention (JITAI) for individuals with SCI as they go about everyday life. A JITAI can prompt an individual to set a PA goal or provide feedback about their PA levels. OBJECTIVE: The primary aim of this study is to investigate whether minutes of moderate-intensity PA among individuals with SCI can be increased by integrating a JITAI with a web-based PA intervention (WI) program. The WI program is a 14-week web-based PA program widely recommended for individuals with disabilities. A secondary aim is to investigate the benefit of a JITAI on proximal PA, defined as minutes of moderate-intensity PA within 120 minutes of a PA feedback prompt. METHODS: Individuals with SCI (N=196) will be randomized to a WI arm or a WI+JITAI arm. Within the WI+JITAI arm, a microrandomized trial will be used to randomize participants several times a day to different tailored feedback and PA recommendations. Participants will take part in the 24-week study from their home environment in the community. The study has three phases: (1) baseline, (2) WI program with or without JITAI, and (3) PA sustainability. Participants will provide survey-based information at the initial meeting and at the end of weeks 2, 8, 16, and 24. Participants will be asked to wear a smartwatch every day for ≥12 hours for the duration of the study. RESULTS: Recruitment and enrollment began in May 2023. Data analysis is expected to be completed within 6 months of finishing participant data collection. CONCLUSIONS: The JITAI has the potential to achieve long-term PA performance by delivering tailored, just-in-time feedback based on the person's actual PA behavior rather than a generic PA recommendation. New insights from this study may guide intervention designers to develop engaging PA interventions for individuals with disability. TRIAL REGISTRATION: ClinicalTrials.gov NCT05317832; https://clinicaltrials.gov/study/NCT05317832. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/57699.

Differential relationships between physical activity and pain phenotypes in individuals with spinal cord injury.

BACKGROUND: Chronic pain affects 70% of individuals with spinal cord injury (SCI) and leads to declines in health and quality of life. Neuropathic and nociceptive pain are phenotypes derived from different mechanisms that contribute to pain perception. The objective of this research was to investigate differential pain responses to moderate-to-vigorous physical activity (MVPA) in two chronic pain phenotypes: neuropathic and nociceptive pain. METHODS: Community-based physical activity levels were collected for one week in 17 individuals with SCI using a wrist-worn accelerometer, and daily pain ratings were assessed and categorized by phenotype. Physical activity levels were summarized to calculate minutes of MVPA. Correlational analyses were conducted to compare relationships between pain intensity and MVPA across individual participants and between pain phenotype groups. RESULTS: The neuropathic pain group revealed significant negative correlation between MVPA and pain intensity. In the nociceptive pain group, there was no significant correlation between MVPA and pain intensity. Further analysis revealed two subgroups of positive (N = 4) and negative (N = 3) correlations between MVPA and pain intensity. Pain location differed between the subgroups of nociceptive pain. Individuals with negative correlation experienced neck and upper back pain, whereas individuals with positive correlation experienced unilateral upper extremity pain. CONCLUSION: Differential relationships exist between pain phenotypes and MVPA in individuals with SCI. Pain location differed between the subgroups of nociceptive pain, which we presume may indicate the presence of nociplastic pain in some individuals. These results may contribute to the advancement of personalized pain management by targeting non-pharmacological interventions for specific pain phenotypes.Trial registration: ClinicalTrials.gov identifier: NCT05236933..

The Effects of Age and Height on Gait Smoothness in Adolescent Athletes.

(1) Background: Despite evidence of increased rates of sports injury during the years surrounding peak growth in adolescents, little is known regarding the relationship between adolescent growth and gait stability. The aim of this study was to gain a better understanding of how chronological age and height relate to gait stability in both male and female adolescents. (2) Methods: Participants (N = 67; females: n = 34, ages 8.7-15.9 years; males: n = 33, ages 10.0-16.7 years) completed two trials of treadmill walking at varying speeds: the preferred walking speed and 30% above and below. Trials were separated by a bout of fatiguing exercises. HarmonicRatios of the trunk, calculated from acceleration signals taken during walking, were used to quantify gait stability. Data were separated by sex and relationships between height and chronological age, and HarmonicRatios were assessed using multiple linear regression. (3) Results: Females' HarmonicRatios improved with chronological age both before and after fatigue. Males' HarmonicRatios increased with chronological age before fatigue; however, this effect was eliminated post-fatigue. Females' height was negatively associated with HarmonicRatios post-fatigue. Males' height was positively associated with HarmonicRatios pre-fatigue. (4) Conclusions: The study findings suggest sex differences in the effects of fatigue on gait stability during adolescence. In both sexes, HarmonicRatios increased with chronological age. These improvements were eliminated for males and altered for females with fatigue. The results of this study indicate the need for the reevaluation of sports progression based on chronological age in adolescents.

Effect of Tele-exercise to Promote Empowered Movement for Individuals With Spinal Cord Injury (TEEMS) Program on Physical Activity Determinants and Behavior: A Mixed Methods Assessment.

OBJECTIVE: To assess the effects of group tele-exercise participation on physical activity (PA) determinants and behavior as identified by social cognitive theory (SCT) in individuals with spinal cord injury (SCI). DESIGN: This clinically registered non-randomized trial [NCT05360719] used a single-group parallel mixed methods design. Quantitative and qualitative primary measures were assessed at pre-program and after 8-week intervention completion (post-program), with an additional 8-week period retention to capture quantitative assessments only. SETTING: Community. PARTICIPANTS: Individuals with chronic SCI (N=22, injury duration 2-50 years) aged 26-68 years (10 male/12 female). INTERVENTION: An 8-week group tele-exercise program for individuals with SCI consisting of biweekly 60-minute classes delivered via live Web-conferencing software. MAIN OUTCOME MEASURES: Exercise self-efficacy (Exercise Self-efficacy Scale for SCI: ESES), outcome expectations for exercise (Multidimensional Outcome Expectations for Exercise: MOEES), weekly PA minutes measured through quantitative assessments (Leisure Time PA Questionnaire for SCI: LTPAQ), and parallel qualitative thematic analysis of focus group interview transcripts. RESULTS: Congruence between numeric and thematic findings was present for exercise self-efficacy and self-evaluative exercise outcome expectations. Improved exercise self-efficacy was influenced by exercise knowledge gained during program participation. Increased expectations of internal exercise outcomes, such as influence on psychological state and overall mood, occurred after program participation. Participant descriptions of the portability and sustainability of the program leading to added movement in everyday life were not reflected in the numeric scores of LTPAQ assessment. CONCLUSIONS: Participation in an 8-week group tele-exercise program positively affected personal determinants of PA behavior immediately after participation. Future investigations should include a control group and biophysical PA measures such as wearable digital health devices.

Potential of social engagement for overcoming barriers to physical activity in individuals with spinal cord injury.

Introduction: Many barriers to physical activity (PA) exist for individuals with spinal cord injury (SCI). Social engagement may improve motivation to perform PA, which in turn may increase PA levels. This pilot study investigates how social engagement facilitated by mobile technology may reduce lack of motivation as a barrier to PA in individuals with SCI and demonstrates design implications for future technologies. Methods: A user-needs survey was conducted with participants in the community. We recruited 26 participants (16 individuals with SCI and 10 family members or peers). A participatory design process using semi-structured interviews was used to identify themes relating to PA barriers. Results: One theme related to PA barriers was lack of PA-focused forums to connect with peers. Participants with SCI considered connecting with other individuals with SCI more motivating than connecting with their family members. Another key finding was that participants with SCI did not perceive that personal fitness trackers were targeted towards wheelchair-based activities. Conclusions: Engagement and communication with peers who have similar functional mobility levels and life experiences can potentially improve motivation for PA; however, PA-motivational platforms are not tailored towards wheelchair-users. Our preliminary findings show that some individuals with SCI are not satisfied with current mobile-technologies for wheelchair-based PA.

Convergent Validity of the Patient Reported Outcome Measurement Information System-Pediatric Physical Activity Instrument (PROMIS®-PA) with Wearable Devices in Adolescents.

The study was conducted mainly to examine the convergent validity of the Patient Reported Outcome Measurement Information System-Pediatric Physical Activity instrument (PROMIS®®®-PA) with step counts from wearable devices and another validated self-reported outcome measure. As a secondary aim, we explored the effect of different recall time frames (7-day, end-of-day [EoD], and ecological momentary assessment [EMA] time frames during the day) in terms of their feasibility and associations with each other and with step counts. This was a prospective cohort study that examined the associations between measures of PA in school-age children and adolescents (n = 84, aged 10-20). The participants wore Fitbit devices for 7 consecutive days, and then completed the 7-day-recall PROMIS-PA short form and Youth Activity Profile (YAP). Additional analyses were completed in a sub-sample (n = 25, aged 11-18 years) using the PROMIS-PA for the EMA at five intervals during the day (shorter form) and at the EoD. In the total sample, the PROMIS-PA results showed positive moderate correlations with the YAP and average daily steps (r = 0.533, p < 0.001 and r = 0.346, p = 0.002, respectively). In the sub-sample, the 7-day PROMIS-PA was highly correlated with the averaged EMA or EoD ratings for the week, and moderately correlated with the daily step counts. These findings support the validity of the PROMIS-PA as a measure of self-reported physical activity. Adolescents demonstrated higher compliance rates and preference for the 7-day recall and EoD assessments compared to more frequent EMA reporting.

Assessing functional recovery for individuals with spinal cord injury post-discharge from inpatient rehabilitation.

OBJECTIVE: To determine the associations between trauma variables, acute phase-related variables, and patient-level characteristics with functional recovery during the first-year post-discharge from inpatient rehabilitation facilities (IRF) for individuals with spinal cord injury (SCI). DESIGN: Retrospective cohort analysis. SETTING: Two SCI Model Centers in Pennsylvania, United States. METHODS: We were able to link 378 individuals with traumatic SCI between the Pennsylvania Trauma Systems Outcomes Study and the National SCI Model Systems databases. Nineteen individuals with SCI were excluded due to missing data. We estimated functional recovery based on changes in functional independence measure (FIM) total motor score during the first-year post-discharge from IRF in 359 individuals with SCI, who did not have any missing data, using ordinary least squares regression (OLS). RESULTS: After discharge from IRF the majority of individuals with SCI improved over the first-year post-injury. Individuals with cervical A-C (injury severity group) who were older had a slight decrease in motor FIM at 1-year post-injury. Regression analysis indicated that lower functional recovery was associated with being of Black and Hispanic race and ethnicity, higher injury severity group, occurrence of non-pulmonary infection during acute care, and longer length of stay at IRF (R2 = 0.36). CONCLUSIONS: Patient-level characteristics, trauma variables, and acute phase-related variables were associated with functional recovery post-discharge from IRF. Further research is necessary to collect and assess post-rehabilitation and socio-economic factors that play a critical role in continued functional recovery in the community.

Enhancing the Content Validity of Self-Reported Physical Activity Self-Efficacy in Adolescents: A Qualitative Study.

PURPOSE: This study's primary purpose was to enhance the content validity of a self-reported measure of self-efficacy for physical activity (PA) in adolescents. This was addressed through assessment of younger and older adolescents' understanding of the construct of self-efficacy for PA, coupled with assessment of the content coverage and comprehensibility of items derived from existing measures. METHODS: Participants completed individual semistructured and cognitive debriefing interviews as well as 3 PA self-efficacy questionnaires. RESULTS: Thematic analysis identified personal and environmental facilitators and barriers to PA self-efficacy. The major categories were physical; psychological; interaction with surroundings; support and relationships; attitudes; and services, systems, and natural environments. Cognitive interviews resulted in the retention of 52 final items: 24 for self-efficacy with perceived facilitators and 28 for self-efficacy to overcome barriers. CONCLUSIONS: This study provides a PA self-efficacy instrument with expanded content coverage that is relevant to adolescents as young as 11 years. With further validation testing in future studies, this instrument will enable pediatric physical therapists and researchers to assess PA self-efficacy and design effective intervention strategies to improve PA.

Evaluating associations between trauma-related characteristics and functional recovery in individuals with spinal cord injury.

OBJECTIVE: To determine the associations between trauma variables, acute phase-related variables, and patient-level characteristics with functional recovery during inpatient rehabilitation for individuals with spinal cord injury (SCI). The associations were evaluated by linking individuals' records between the Pennsylvania Trauma Systems Outcomes Study and the National SCI Model Systems databases. DESIGN: Retrospective cohort analysis. SETTING: Two SCI Model Centers in Pennsylvania, United States. METHODS: We used a record linkage toolkit in Python to link 735 individuals with traumatic SCI between the databases. The percentage for true-match and error were 92.0% and 0.1%, respectively. The functional recovery during inpatient rehabilitation was determined in 604 individuals with SCI by ordinary least squares regression (OLS) and gradient boosting regression (GBR) analyses. RESULTS: The OLS and GBR analyses indicated older age, greater impairment (SCI level combined with American Spinal Injury Association impairment scale), presence of diabetes mellitus, pulmonary complications during acute care, and longer length of stay at an inpatient rehabilitation facility were associated with lower functional recovery (OLS R2 = 0.56 and GBR R2 = 0.58). CONCLUSIONS: Trauma and acute care variables in addition to patient characteristics were associated with functional recovery during inpatient rehabilitation in individuals with SCI. Further investigation is needed to understand the role of diabetes mellitus and pulmonary complications, which have not been previously associated with functional recovery in individuals with SCI.

Staying active after rehab: Physical activity perspectives with a spinal cord injury beyond functional gains.

Lifestyle physical activity following spinal cord injury (SCI) is critical for functional independence, mental wellness, and social participation, yet nearly 50% of individuals with SCI report no regular exercise. The objective of this study was to better understand factors leading to this participation gap by capturing the physical activity perspectives of individuals living with SCI. We completed small group interviews with nine individuals living with SCI across the United States. Iterative thematic analysis systematically revealed meaningful core concepts related to physical activity engagement with SCI. Emergent themes revealed challenges to lifestyle physical activity behavior including gaps in physical activity education, isolation during psychological adjustment, and knowledge limitations in community exercise settings. A secondary theme related to the COVID-19 pandemic emerged, highlighting additional environmental constraints affecting participation. Our findings suggest that most physical activity education is delivered during inpatient rehabilitation and is related to physical function. Lifetime physical activity strategies are achieved through self-education and peer networking. Personal motivators for physical activity include secondary condition prevention, while social and emotional barriers prevent regular adherence. These findings can inform the development and delivery of physical activity programs to maximize physical activity engagement in individuals living with chronic SCI.

Factors associated with post-acute functional status and discharge dispositions in individuals with spinal cord injury.

BACKGROUND: Research has evaluated the effect of surgical timing on patient functional recovery in individuals with spinal cord injury (SCI); however, there is a critical need to assess how demographics, clinical characteristics, and process of care affect functional outcomes. OBJECTIVE: We examined the association between demographic, clinical, and process of care factors with post-acute functional status (locomotion and transfer mobility scores) and discharge disposition (home vs. institution) in individuals with SCI. METHODS: This study was a retrospective cohort analysis of the Pennsylvania Trauma Systems Outcomes Study (PTOS) database for individuals with traumatic SCI (N = 2223). We conducted multinomial and binomial logistic regression analyses to examine post-acute functional status and discharge disposition, respectively. RESULTS: The results indicated that older age, longer length of stay, lower Glasgow Coma Scale (GCS), higher Injury Severity Score (ISS), and individuals with tetraplegia had significantly lower motor functional score at discharge from an acute hospital. In addition, older age, individuals with public-sponsored insurance, longer length of stay, lower GCS, and higher ISS had significantly higher odds of being discharged to an institution, as compared to home. Individuals of Hispanic ethnicity, as compared to White, had lower odds of being discharged to an institution. CONCLUSIONS: The regression models developed in this study were able to better classify discharge destinations compared to the functional outcomes at discharge from the acute hospital. Further research is necessary to determine how these factors and their associations vary nationally across the US, which have the potential to inform trauma and acute care post-SCI.

Classifying and tracking rehabilitation interventions through machine-learning algorithms in individuals with stroke.

INTRODUCTION: Stroke is the leading cause of disability worldwide. It has been well-documented that rehabilitation (rehab) therapy can aid in regaining health and function for individuals with stroke. Yet, tracking in-home rehab continues to be a challenge because of a lack of resources and population-scale demands. In order to address this gap, we implemented a methodology to classify and track rehab interventions in individuals with stroke. METHODS: We developed personalized classification algorithms, including neural network-based algorithms, to classify four rehab exercises performed by two individuals with stroke who were part of a week-long therapy camp in Jamaica, a low- and middle-income country. Accelerometry-based wearable sensors were placed on each upper and lower limb to collect movement data during therapy. RESULTS: The classification accuracy for traditional and neural network-based algorithms utilizing feature data (e.g., number of peaks) from the sensors ranged from 64 to 94%, respectively. In addition, the study proposes a new method to assess change in bilateral mobility over the camp duration. CONCLUSION: The results of this pilot study indicate that personalized supervised learning algorithms can be used to classify and track rehab activities and functional outcomes in resource limited settings such as LMICs.

Timing and pattern of readmission in individuals with spinal cord injury in the setting of a specialized medical home.

BACKGROUND: The rate of readmission in individuals with spinal cord injury (SCI) is known to be high (28% to 45%) during the first year post-injury and post-rehabilitation. However, there are several critical gaps in our knowledge including the timing pattern of medical complications and the pattern of health complications associated with readmissions. OBJECTIVE: To identify the timing and pattern of complications associated with hospital readmissions in individuals with traumatic SCI and non-traumatic spinal cord disorders (SCI) post-discharge from an inpatient rehabilitation facility (IRF). DESIGN: Secondary analysis of a three year prospective cohort study. SETTING: An SCI medical home. PARTICIPANTS: Individuals who were readmitted (n = 53) within the first year (N = 176) post-discharge from an IRF. INTERVENTIONS: N/A. OUTCOME MEASURES: Timing and pattern of all-cause hospital readmissions. RESULTS: Eighty one percent of the readmitted patients experienced readmission within the first six months after discharge, and 36% of the initial readmissions occurred within 30 days of discharge from an IRF. The trend line for the timing of the first readmission post-discharge from an IRF was curvilinear, with a sharp decrease in the number of new patients readmitted for months 1-7 and then a slight increase between 9 and 12 months. Urological and respiratory complications were related to repeat readmissions. CONCLUSION: The patient is at the greatest risk of readmission in the first 6 months, with a secondary increase in risk at 9 months. Possible reasons may include reduction in in-home and outpatient therapy and skilled nursing over the first year post-SCI.

Relationship between pain, fatigue, and physical activity levels during a technology-based physical activity intervention.

Objective: The majority of individuals with spinal cord injury (SCI) experience chronic pain. Chronic pain can be difficult to manage because of variability in the underlying pain mechanisms. More insight regarding the relationship between pain and physical activity (PA) is necessary to understand pain responses during PA. The objective of this study is to explore possible relationships between PA levels and secondary conditions including pain and fatigue.Design: Prospective cohort analysis of a pilot study.Setting: Community.Participants: Twenty individuals with SCI took part in the study, and sixteen completed the study.Interventions: Mobile-health (mHealth) based PA intervention for two-months during the three-month study.Outcome measures: Chronic Pain Grade Scale (CPGS) questionnaire, The Wheelchair User's Shoulder Pain Index (WUSPI), Fatigue Severity Scale (FSS), and PA levels measured by the mHealth system.Results: A positive linear relationship was found between light-intensity PA and task-specific pain. However, the relationship between moderate-intensity PA and pain interference was best represented by a curvilinear relationship (polynomial regression of second order). Light-intensity PA showed positive, linear correlation with fatigue at baseline. Moderate-intensity PA was not associated with fatigue during any phase of the study.Conclusion: Our results indicated that PA was associated with chronic pain, and the relationship differed based on intensity and amount of PA performed. Further research is necessary to refine PA recommendations for individuals with SCI who experience chronic pain.Trial registration: ClinicalTrials.gov identifier: NCT03773692.

Examining the relationship between community mobility and participation using GPS and self-report data.

Higher levels of community mobility have been shown to be associated with better physical health, mental health, and quality of life. The ability to move about one's community is also expected to facilitate community participation, which is an aspect of health functioning. This study uses Global Positioning Systems (GPS) technology to track various dimensions of community mobility, such as destinations, time outside the home, and distance traveled, and examine the relationship between these variables and community participation in a sample of individuals with serious mental illnesses (SMI). This population was selected because they are known to have diminished health functioning in terms of their community participation, and the goal is to explore the extent to which mobility limitations may account for this. A total of 103 individuals with serious mental illnesses were recruited from mental health agencies and consented to having their mobility tracked using GPS for 13 days and answering questions about their community-based activities. Greater amount of participation was associated with having more destinations and spending more time out of the house, but not with traveling larger distances and having a greater activity space. None of the mobility variables were related to the number of important participation areas or sufficiency of participation. The findings support the hypothesis that greater mobility is related to more participation, although satisfaction with the degree to which one participates does not appear to be impacted, suggesting that other factors need to be accounted for. Health policymakers and providers should pay attention to community mobility as a factor that affects health outcomes such as participation, in individuals with serious mental illnesses, and other populations. In particular, attending to access to personal transport, public transportation, and other mobility options appears to be important, as well as interventions aimed at encouraging greater community mobility.

Movement Coordination During Humeral Elevation in Individuals With Newly Acquired Spinal Cord Injury.

Humeral elevation is a critical motion for individuals who use a manual wheelchair given that, in a typical day, wheelchair users reach overhead 5 times more often than able-bodied controls. Kinematic analyses in individuals with chronic spinal cord injury (SCI) have focused on weight-bearing tasks rather than overhead reaching. This technical report presents shoulder movement coordination during overhead reaching in individuals with newly acquired SCI. Eight volunteers with acute SCI and 8 matched, uninjured controls participated. Three-dimensional kinematics were collected during seated, humeral elevation. Scapular and thoracic rotations during humeral elevation were averaged across repetitions. The linear relationship of scapular upward rotation to humeral elevation provided movement coordination analysis. Maximal elevation was reduced in SCI with increased thoracic kyphosis. Medium to large effect sizes were found at each elevation angle, with reduced scapular external rotation, posterior tilt, and increased thoracic kyphosis for those with SCI. The linear relationship occurred later and within a significantly (P = .02) smaller range of humeral elevation in SCI. Altered movement coordination, including a diminished linear association of scapular upward rotation and humeral elevation (scapulohumeral rhythm), is found with reduced maximal elevation and increased thoracic kyphosis during overhead reaching tasks in those with acute SCI.

Use of Surface Electromyography to Measure Muscle Fatigue in Patients in an Acute Care Hospital.

BACKGROUND: Functional outcomes with early rehabilitation in the acute care setting have improved; however, an improved understanding of muscle fatigue using surface electromyography (sEMG) is warranted to better guide patient-centered exercise prescription. OBJECTIVES: The objectives of this study were to assess the safety and feasibility of collecting sEMG at the acute care bedside and to determine differences in muscle fatigue during isometric and dynamic submaximal contractions among patients in the hospital, healthy younger participants, and healthy older participants. DESIGN: The study used an observational cohort design. METHODS: There were 37 participants. Median frequency (Fmed) of the myoelectric signal of the quadriceps femoris muscles and time to task failure (TTTF) were measured using sEMG during an isometric and dynamic fatiguing contraction. Primary analysis compared TTTF between groups for both types of contractions. Secondary analysis compared Fmed at initiation and termination of fatiguing contraction. RESULTS: High-quality sEMG measures were safe and feasible to collect at the acute care bedside with no adverse events. There was a statistically significant difference in TTTF between groups after isometric and dynamic contractions; hospitalized patients fatigued faster than healthy younger and healthy older participants after both contractions. With the exception of the vastus lateralis during a dynamic contraction in healthy younger and hospitalized patients, there was a statistically significant difference between Fmed at initiation and termination of contraction, indicating that subjects' muscles did truly fatigue. LIMITATIONS: A limitation of the study was the small sample size of patients who were hospitalized without matched controls. CONCLUSIONS: sEMG is a lab quantitative technique that was found to be safe and feasible to assess muscle fatigue in the acute care environment. The protocol yielded similar results to previously published literature for healthy younger and healthy older people. Further research is needed to better understand how to integrate sEMG findings into patient-centered exercise prescriptions.

Factors associated with multiple hospital readmissions for individuals with spinal cord injury.

OBJECTIVE: To identify patient-level and clinical factors associated with multiple hospital readmissions in individuals with spinal cord injury (SCI). DESIGN: Retrospective cohort analysis of the publicly available dataset from the SCI Rehabilitation (SCIRehab) study. SETTING: Six rehabilitation centers in the U.S. that participated in the SCIRehab study. Participants: Individuals with traumatic SCI (N=1371) who were consecutively enrolled in the SCIRehab study. OUTCOME MEASURES: The primary outcome was all-cause hospital readmission within 1 year of discharge from a rehabilitation center. The patient-level and clinical factors include employment status, depression, caregiver support, state-funded insurance, functional status, and rehabilitation services. RESULTS: Of the 1170 participants included in the study, 228 were readmitted once and 120 were readmitted multiple times. In our study, 34.2% and 10.8% were readmitted more than once due to genitourinary and respiratory conditions, respectively. Lower utilization of rehabilitation services, lower functional status, unemployment, and depression were associated with higher odds of being readmitted multiple times within one year of discharge from inpatient rehabilitation facility. CONCLUSION: Psychosocial and clinical factors were associated with increased risk for multiple readmissions in individuals with SCI. In order to reduce recurrent readmissions in individuals with SCI, further research is necessary to maximize efficacy of risk factor modification and prevention strategies.

Correction: Mobile health-based physical activity intervention for individuals with spinal cord injury in the community: A pilot study.

[This corrects the article DOI: 10.1371/journal.pone.0223762.].