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OBJECTIVE: To assess the effectiveness of group wheelchair maintenance training and investigate participant characteristics associated with responsiveness to training. DESIGN: Randomized control trial with an immediate group and waitlist control group (WLCG) who received the intervention after a 6-month delay. SETTING: Four Spinal Cord Injury Model Systems Centers. PARTICIPANTS: Manual (MWC) and power wheelchair (PWC) users with spinal cord injury (n=80 and 67, respectively). INTERVENTION: 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-month, 6-month-pre-training (WLCG only), and 1-year (immediate only). RESULTS: Following the intervention, participants in both the immediate and WLCG improved in maintenance capacity (MWC and PWC, p

Objective To evaluate the reliability, standard error of measurement, minimum detectable change, and item-level consistency of the Transfer Assessment Instrument (TAI) version 4.0 when used to evaluate transfer quality remotely. Design Participants transferred from their wheelchair to a mat table (transfer 1), repeated this after a 10-minute delay to assess intrarater reliability (transfer 2), and repeated this 1-2 days later to assess test-retest reliability (transfer 3). Each transfer was scored in person by 4 raters and asynchronously by a remote clinician rater. Setting 2017 National Veterans Wheelchair Games. Participants Convenience sample of 44 full-time wheelchair users (N=44). Interventions Not applicable. Main Outcome Measures TAI total score, subscores (wheelchair setup, body setup, flight/landing), and item scores (15 items). Results Moderate to excellent reliability was found when scoring remotely for TAI total and subscores for intrarater (intraclass correlation coefficient (ICC(3,1)=0.687-0.854), test-retest (ICC(3,1)=0.695-0.836), and interrater reliability (ICC(3,5)=0.746-0.962). Remote rater total score and flight/landing subscore were greater (indicating higher transfer quality) compared to the average in-person raters (P=.021 and P=.005, respectively). There were no differences between transfers 1-3 in remote rater scores. Item-level percentage agreement between the remote rater and in-person exceeded the 75% cutoff for clinical utility for all items. Conclusions The TAI is a reliable outcome measure for assessing transfer technique remotely.

Manual interactions with objects are supported by tactile signals from the hand. This tactile feedback can be restored in brain-controlled bionic hands via intracortical microstimulation (ICMS) of somatosensory cortex (S1). In ICMS-based tactile feedback, contact force can be signaled by modulating the stimulation intensity based on the output of force sensors on the bionic hand, which in turn modulates the perceived magnitude of the sensation. In the present study, we gauged the dynamic range and precision of ICMS-based force feedback in three human participants implanted with arrays of microelectrodes in S1. To this end, we measured the increases in sensation magnitude resulting from increases in ICMS amplitude and participant’s ability to distinguish between different intensity levels. We then assessed whether we could improve the fidelity of this feedback by implementing “biomimetic” ICMS-trains, designed to evoke patterns of neuronal activity that more closely mimic those in natural touch, and by delivering ICMS through multiple channels at once. We found that multi-channel biomimetic ICMS gives rise to stronger and more distinguishable sensations than does its single-channel counterpart. We conclude that multi-channel biomimetic ICMS conveys finely graded force feedback that more closely approximates the sensitivity conferred by natural touch.

The most prominent role of motor cortex is generating patterns of neural activity that lead to movement, but it is also active when we simply imagine movements in the absence of actual motor output. Despite decades of behavioral and imaging studies, it is unknown how the specific activity patterns and temporal dynamics within motor cortex during covert motor imagery relate to those during motor execution. Here we recorded intracortical activity from the motor cortex of two people with residual wrist function following incomplete spinal cord injury as they performed both actual and imagined isometric wrist extensions. We found that we could decompose the population-level activity into orthogonal subspaces such that one set of components was similarly active during both action and imagery, and others were only active during a single task type—action or imagery. Although they inhabited orthogonal neural dimensions, the action-unique and imagery-unique subspaces contained a strikingly similar set of dynamical features. Our results suggest that during motor imagery, motor cortex maintains the same overall population dynamics as during execution by recreating the missing components related to motor output and/or feedback within a unique imagery-only subspace.

The objective of the study was to evaluate the impact of distractions on intracortical brain–computer interface (BCI) performance. Two individuals with tetraplegia had microelectrode arrays implant...

Modern myoelectric prosthetic hands have multiple independently controllable degrees of freedom, but require constant visual attention to use effectively. Somatosensory feedback provides information not available through vision alone and is essential for fine motor control of our limbs. Similarly, stimulation of the nervous system can potentially provide artificial somatosensory feedback to reduce the reliance on visual cues to efficiently operate prosthetic devices. We have shown previously that epidural stimulation of the lateral cervical spinal cord can evoke tactile sensations perceived as emanating from the missing arm and hand in people with upper-limb amputation. In this case study, two subjects with upper-limb amputation used this somatotopically-matched tactile feedback to discriminate object size and compliance while controlling a prosthetic hand. With less than 30 min of practice each day, both subjects were able to use artificial somatosensory feedback to perform a subset of the discrimination tasks at a success level well above chance. Subject 1 was consistently more adept at determining object size (74% accuracy; chance: 33%) while Subject 2 achieved a higher accuracy level in determining object compliance (60% accuracy; chance 33%). In each subject, discrimination of the other object property was only slightly above or at chance level suggesting that the task design and stimulation encoding scheme are important determinants of which object property could be reliably identified. Our observations suggest that changes in the intensity of artificial somatosensory feedback provided via spinal cord stimulation can be readily used to infer information about object properties with minimal training.

SUMMARYIn the United States, over 1.5 million people live with lower-limb amputation. Existing prosthetic limbs do not restore somatosensory feedback from the limb, resulting in functional impairments including balance deficits and an increased risk of falls. Further, these prostheses do not alleviate the severe phantom limb pain that often follows amputation. Leveraging clinically available spinal cord stimulation electrodes, we designed a system that restores somatosensation in the missing limb, thereby improving balance and gait and reducing phantom limb pain. We show that spinal cord stimulation can evoke sensations in the missing foot and that we can control the location and intensity of those sensations. Further, by modulating stimulation intensity in real time based on signals from a wireless pressure-sensitive shoe insole, subjects exhibit improvements in functional measures of balance and gait stability. Finally, over the duration of the implant period, subjects experienced a clinically meaningful decrease in phantom limb pain. These combined results demonstrate that, with an electrode technology that is currently in widespread clinical use, our approach has the potential to become an important intervention for lower-limb amputation.

Motor (M1) and somatosensory (S1) cortex play a critical role in motor control but the nature of the signaling between these structures is not known. To fill this gap, we recorded – in three human participants whose hands were paralyzed as a result of a spinal cord injury – the responses evoked in the hand and arm representations of primary motor cortex (M1) while we delivered ICMS to the somatosensory cortex (S1). We found that ICMS of S1 activated some M1 neurons at short, fixed latencies, locked to each pulse in a manner consistent with monosynaptic activation. However, most of the changes in M1 firing rates were much more variable in time, suggesting a more indirect effect of the stimulation. The spatial pattern of M1 activation varied systematically depending on the stimulating electrode: S1 electrodes that elicited percepts at a given hand location tended to activate M1 neurons with movement fields at the same location. However, the indirect effects of S1 ICMS on M1 were strongly context dependent, such that the magnitude and even sign relative to baseline varied across tasks. We tested the implications of these effects for brain-control of a virtual hand, in which ICMS was used to convey tactile feedback about object interactions. While ICMS-evoked activation of M1 disrupted decoder performance, this disruption could be minimized with biomimetic stimulation, which emphasizes contact transients at the onset and offset of grasp, reduces sustained stimulation, and has been shown to convey useful contact-related information.SignificanceMotor (M1) and somatosensory (S1) cortex play a critical role in motor control but the nature of the signaling between these structures is not known. To fill this gap, we recorded from M1 while delivering intracortical microstimulation (ICMS) to S1 of three human participants, whose hands were paralyzed by spinal cord injury. We found that ICMS activates M1 and that the motor fields of activated M1 neurons match the sensory fields of the stimulated S1 electrodes. These findings have important implications for using ICMS to convey tactile feedback for brain-controlled bionic hands. Indeed, the ICMS-evoked M1 activity worsens control of the hand. Fortunately, this effect is minimized by using biomimetic tactile feedback, which emphasizes contact transients and reduces sustained ICMS.

A boost for brain–computer interfaces The finely controlled movement of our limbs requires two-way neuronal communication between the brain and the body periphery. This includes afferent information from muscles, joints, and skin, as well as visual feedback to plan, initiate, and execute motor output. In tetraplegia, this neural communication is interrupted in both directions at the level of the spinal cord. Brain–computer interfaces have been developed to produce voluntary motor output controlled by directly recording from brain activity. Flesher et al. added an afferent channel to the brain–computer interface to mimic sensory input from the skin of a hand (see the Perspective by Faisal). The improvements achieved by adding the afferent input were substantial in a battery of motor tasks tested in a human subject. Science , abd0380, this issue p. 831 ; see also abi7262, p. 791

Modern myoelectric prosthetic hands have multiple independently controllable degrees of freedom, but require constant visual attention to use effectively. As we know from motor control of our native limbs, somatosensory feedback is essential to control our movements and provides information not available through vision alone. Similarly, stimulation of the nervous system can potentially provide artificial somatosensory feedback to reduce the reliance on visual cues to efficiently operate prosthetic devices. We have shown previously that epidural stimulation of the lateral cervical spinal cord can evoke tactile sensations perceived as emanating from the missing arm and hand in people with upper-limb amputation. In this study, two subjects with upper-limb amputation used this somatotopically-matched tactile feedback to discriminate object size and compliance while controlling a prosthetic hand. With less than 30 minutes of training each day, both subjects were able to use artificial somatosensory feedback to perform a subset of the discrimination tasks at a success level well above chance. Subject 1 was consistently more adept at determining object size (74% accuracy; chance: 33%) while Subject 2 achieved a higher accuracy level in determining object compliance (60% accuracy; chance 33%). In each subject, discrimination of the other object property was only slightly above or at chance level suggesting that the task design and stimulation encoding scheme are important determinants of which object property could be reliably identified. Our observations suggest that artificial somatosensory feedback provided via spinal cord stimulation can be readily used to infer information about the real-world with minimal training, but that task design is critical and that performance improvements may not generalize across tasks.

To test the hypothesis that remote learning to teach clinicians manual wheelchair skills is efficacious.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.Across 41participants, scores were higher at follow-up compared to baseline for WST-Q capacity (73.9 ± 19.1 vs 16.8 ± 15.6,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.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.

BACKGROUND Intracortical microelectrode arrays have enabled people with tetraplegia to use a brain-computer interface for reaching and grasping. In order to restore dexterous movements, it will be necessary to control individual fingers. OBJECTIVE To predict which finger a participant with hand paralysis was attempting to move using intracortical data recorded from the motor cortex. METHODS A 31-yr-old man with a C5/6 ASIA B spinal cord injury was implanted with 2 88-channel microelectrode arrays in left motor cortex. Across 3 d, the participant observed a virtual hand flex in each finger while neural firing rates were recorded. A 6-class linear discriminant analysis (LDA) classifier, with 10 × 10-fold cross-validation, was used to predict which finger movement was being performed (flexion/extension of all 5 digits and adduction/abduction of the thumb). RESULTS The mean overall classification accuracy was 67% (range: 65%-76%, chance: 17%), which occurred at an average of 560 ms (range: 420-780 ms) after movement onset. Individually, thumb flexion and thumb adduction were classified with the highest accuracies at 92% and 93%, respectively. The index, middle, ring, and little achieved an accuracy of 65%, 59%, 43%, and 56%, respectively, and, when incorrectly classified, were typically marked as an adjacent finger. The classification accuracies were reflected in a low-dimensional projection of the neural data into LDA space, where the thumb-related movements were most separable from the finger movements. CONCLUSION Classification of intention to move individual fingers was accurately predicted by intracortical recordings from a human participant with the thumb being particularly independent.

ObjectiveThis study aimed to identify targets of intervention for reducing shoulder pain in wheelchair users with spinal cord injury (SCI) by (1) examining changes in subacromial space [acromiohumeral distance (AHD) and occupation ratio (OccRatio)] with fatiguing wheelchair propulsion, and different loading conditions [unloaded position vs. weight relief lifts (WRL)]; (2) associating these changes with wheelchair user capacity, as well as (3) identifying subject characteristics associated with subacromial space, such as sex, lesion level, time since injury, body mass index and impaired shoulder range of motion.MethodsFifty manual wheelchair users with SCI [11 females, age = 50.5 (9.7) years, time since injury = 26.2 (11.4) years] participated in this quasi-experimental one-group pretest-posttest study. Ultrasound images were used to define AHD during an unloaded position, and during personal and instructed WRL before and after fatiguing wheelchair propulsion. Furthermore, supraspinatus and biceps thickness defined from ultrasound images were used to calculate OccRatios. Wheelchair user capacity was quantified as functional strength (maximum resultant force reached during maximum isometric forward push) and anaerobic work capacity (highest power output reached during 15-m sprint test). Multilevel mixed-effects linear regression analyses controlling for between subject variability and covariables were performed to address the research questions.ResultsAHD was significantly smaller during personal WRL (p < 0.001) and instructed WRL (p = 0.009, AHD both 11.5 mm) compared to the unloaded position (11.9 mm). A higher wheelchair user capacity (higher anaerobic work capacity) reduced the impact of WRL on AHD decrease. The fatiguing wheelchair propulsion had no effect on AHD (p = 0.570) and on OccRatio of supraspinatus (p = 0.404) and biceps (p = 0.448). Subject characteristics related to a larger subacromial space were lower lesion level, shorter time since injury, impaired external rotation, a lower body mass index and a higher anaerobic work capacity.ConclusionThis study showed a significant reduction in AHD during WRL with no effect of fatiguing wheelchair propulsion on the subacromial space in wheelchair users with SCI. A higher anaerobic work capacity was beneficial in stabilizing the shoulder during WRL. Our findings may assist clinicians in designing a shoulder injury prevention program.

Background: Specialty palliative care (SPC) provides patient-centered care to people with serious illness and may reduce costs. Specific cost-saving functions of SPC remain unclear. Objectives: (1) To assess the effect of SPC on inpatient costs and length of stay (LOS) and (2) to evaluate differences in costs by indication and timing of SPC. Design: Case–control with in patients who received an SPC consultation and propensity matched controls. Setting: One large U.S. integrated delivery finance system. Measurements: Using administrative data, we assessed costs associated with inpatient stays, a subset of whom received an SPC consultation. Consultations were stratified by reasons based on physician discretion: goals of care, pain management, hospice evaluation, nonpain symptom management, or support. The primary outcome was total operating costs and the secondary outcome was hospital LOS. Results: In total, 1404 patients with SPC consultations associated with unique hospital encounters were matched with 2806 controls. Total operating costs were lower for patients who received an SPC consultation when the consultation was within 0 to 1 days of admission ($6,924 vs. $7,635, p = 0.002). Likewise, LOS was shorter (4.3 vs. 4.7 days, p

The shortage of physician-scientists in physical medicine and rehabilitation remains a critical problem. The Rehabilitation Medicine Scientist Training Program was developed in 1995 to provide structured career development training for aspiring rehabilitation medicine researchers. Initially funded by a 5-yr K12 grant from the National Institutes of Health National Center for Medical Rehabilitation Research, the structure was revised in 2001, continued in a stable format through three additional funding cycles (2001-2006, 2006-2012, and 2012-2016), and was again revised to a research education program (National Institutes of Health R25) model in 2019. With this change in format of the Rehabilitation Medicine Scientist Training Program, we now report the productivity of funded trainees and discuss future directions informed by the Rehabilitation Medicine Scientist Training Program's current R25 structure.

OBJECTIVE. Intracortical brain-computer interfaces (iBCI) have the potential to restore independence for individuals with significant motor or communication impairments. One of the most realistic avenues for clinical translation of iBCI technology is enabling control of a computer cursor—i.e. movement-related neural activity is interpreted (decoded) and used to drive cursor function. Here we aim to improve cursor click decoding to allow for both point-and-click and click-and-drag control. APPROACH. Using chronic microelectrode arrays implanted in the motor cortex of two participants with tetraplegia, we identified prominent neural responses related to attempted hand grasp. We then developed a new approach for decoding cursor click (hand grasp) based on the most salient responses. MAIN RESULTS. We found that the population-wide response contained three dominant components related to hand grasp: an onset transient response, a sustained response, and an offset transient response. The transient responses were larger in magnitude—and thus more reliably detected—than the sustained response, and a click decoder based on these transients outperformed the standard approach of binary state classification. SIGNIFICANCE: A transient-based approach for identifying hand grasp can provide a high degree of cursor click control for both point-and-click and click-and-drag applications. This generalized click functionality is an important step toward high-performance cursor control and eventual clinical translation of iBCI technology.

ObjectiveThis study aimed to identify acute changes in biceps and supraspinatus tendon characteristics before and after a graded exercise test to exhaustion (GXT) in highly trained wheelchair rugby (WR) athletes. A secondary aspect was to define chronic tendon adaptations related to the impairment of the athlete and the occupation of the tendon within the subacromial space (occupation ratio).MethodsTwelve WR athletes with different impairments (age = 32 ± 6 years; body mass = 67.2 ± 11.2 kg; 9.0 ± 3.6 years competing) volunteered for this study. Performance Corrected Wheelchair Users Shoulder Pain Index was used to quantify shoulder pain. Quantitative Ultrasound Protocols (QUS) were used to define supraspinatus and biceps tendon thickness, echogenicity, and echogenicity ratio of both dominant and non-dominant shoulder before and after the GXT including 22 ± 3.1 min submaximal propulsion and 10.2 ± 1.7 min maximal propulsion on a treadmill. Furthermore, the acromio-humeral distance (AHD) defined from ultrasound (US) images was used to calculate the occupation ratios.ResultsA mixed-effect multilevel analysis that included shoulder as grouping variable, demonstrated a significant reduction in the echogenicity of the biceps following GXT whilst controlling for impairment [spinal cord injury (SCI) and non-SCI] and the occupation ratio (β = −9.01, SEβ = 2.72, p = 0.001, 95% CI = [−14.34; −3.68]). This points toward fluid inflow into the tendon that may be related to overload and acute inflammation. In addition, persons with a SCI (n = 8) had a thicker supraspinatus tendon in comparison to persons with non-SCI (n = 3) which may be related to chronic tendon adaptations (β = −0.53 mm, SEβ = 0.26, p = 0.038, 95% CI = [−1.04; −0.03]). Finally, a greater occupation ratio was associated with signs of tendinopathy (i.e., greater biceps and supraspinatus tendon thickness, and lower supraspinatus echogenicity and echogenicity ratio).ConclusionAcute biceps tendon adaptations in response to the GXT in highly trained WR athletes were evident with chronic adaptations in the supraspinatus tendon being related to the impairment of the athlete. Ultrasound can be used to monitor tendon adaptations in WR athletes for medical diagnosis to assist the scheduling and type of training.

Microstimulation in the somatosensory cortex can evoke artificial tactile percepts and can be incorporated into bidirectional brain–computer interfaces (BCIs) to restore function after injury or disease. However, little is known about how stimulation parameters themselves affect perception. Here, we stimulated through microelectrode arrays implanted in the somatosensory cortex of two human participants with cervical spinal cord injury and varied the stimulus amplitude, frequency, and train duration. Increasing the amplitude and train duration increased the perceived intensity on all tested electrodes. Surprisingly, we found that increasing the frequency evoked more intense percepts on some electrodes but evoked less-intense percepts on other electrodes. These different frequency–intensity relationships were divided into three groups, which also evoked distinct percept qualities at different stimulus frequencies. Neighboring electrode sites were more likely to belong to the same group. These results support the idea that stimulation frequency directly controls tactile perception and that these different percepts may be related to the organization of somatosensory cortex, which will facilitate principled development of stimulation strategies for bidirectional BCIs.

OBJECTIVE The aims of the study were to examine whether fatigue-inducing wheelchair propulsion changes neuromuscular activation and propulsion biomechanics and to determine predictor variables for susceptibility to fatigue. DESIGN This study with a quasi-experimental, one-group, pretest-posttest design investigates a population-based sample of wheelchair users with a spinal cord injury (n = 34, age: 50.8 ± 9.7 yrs, 82% males). Neuromuscular activation and propulsion biomechanics during treadmill propulsion at 25 W and 45 W were assessed before and after a protocol designed to cause fatigue. RESULTS With the induced fatigue, wheelchair users propelled with increased neuromuscular activation in the pectoralis major pars sternalis, deltoideus pars acromialis and upper trapezius (45 W, P < 0.05), and a slightly reduced push angle (25 W: 75-74 degrees, P < 0.05, 45 W: 78-76 degrees, P < 0.05). Wheelchair users susceptible to fatigue (47%) were more likely to have a complete lesion, to be injured at an older age, and had less years since injury. This group propelled in general with shorter push angle and greater maximum resultant force, had a greater anaerobic capacity, and had less neuromuscular activation. CONCLUSIONS Compensation strategies in response to fatiguing propulsion could increase the risk for shoulder injury. Predictor variables for susceptibility to fatigue inform interventions preserving shoulder health and include lesion characteristics, propulsion technique, anaerobic capacity, and neuromuscular activation. TO CLAIM CME CREDITS Complete the self-assessment activity and evaluation online at http://www.physiatry.org/JournalCME CME OBJECTIVES: Upon completion of this article, the reader should be able to: (1) Explain a neuromuscular compensation strategy and the corresponding muscles in response to fatiguing wheelchair propulsion; (2) Recommend propulsion biomechanics associated to reduced susceptibly to fatiguing wheelchair propulsion; and (3) List examples of predictor variables of susceptibility to fatigue. LEVEL Advanced. ACCREDITATION The Association of Academic Physiatrists is accredited by the Accreditation Council for Continuing Medical Education to provide continuing medical education for physicians.The Association of Academic Physiatrists designates this journal-based CME activity for a maximum of 1.0 AMA PRA Category 1 Credit(s)™. Physicians should only claim credit commensurate with the extent of their participation in the activity.

Microdialysis quantifies in vivo soft-tissue biochemical concentrations via passive diffusion of interstitial molecules through a porous membrane into a dialysate. The purpose of this pilot study was to evaluate a technique to measure inflammatory cytokines associated with rotator cuff tendinopathy by inserting a microdialysis catheter into the posterior glenohumeral joint. The technique was tested in a convenience sample of six pain-free, able-bodied veterans. Complete dialysate samples were collected in two participants. Two participants' sample volumes were smaller than what was required for analysis (30 μl) and thus were diluted. Catheter failures in two participants prevented collection altogether. Three cytokine concentrations were quantified: interleukin-1 receptor antagonist, interleukin 8, and regulated on activation, normal T-cell expressed and secreted. Microdialysis is not recommended for use in the glenohumeral joint, yet quantification of glenohumeral joint cytokines could yield valuable information to better understand pathophysiology of the joint and its surrounding tissues. Another technique, such as joint lavage, may be a more attractive alternative to overcome the limitations of microdialysis in the glenohumeral joint.

Physician scientists play an important role in the translation of research findings to patient care; however, their training faces numerous challenges. Residency research track programs represent an opportunity to facilitate the training of future physician scientists in physical medicine and rehabilitation, although optimal program organization and long-term outcomes remain unknown. The Rehabilitation Medicine Scientist Training Program is a National Institutes of Health-funded program aimed at addressing the shortage of physician researchers in the field of physical medicine and rehabilitation by providing instruction, mentorship, and networking opportunities for a successful research career. While the opportunities provided through the Rehabilitation Medicine Scientist Training Program provide critical education and guidance at a national level, trainees are most successful with availability of strong local support and mentorship. The purpose of this article was to present a realistic and easily applicable structure for a physical medicine and rehabilitation residency research track that can be used in concert with the Rehabilitation Medicine Scientist Training Program.

OBJECTIVE: To determine the effectiveness of a web-based, direct-to-user transfer training program in improving transfer quality and maintaining improvements for up to one-month post-training as compared to a control group. DESIGN: Randomized control study with participants randomized to an immediate intervention (IIG) or waitlist control group (WLCG) that received the training after a 6-month delay. SETTING: Wherever the participants accessed the web-based training, likely the home environment. PARTICIPANTS: Convenience sample of full-time wheelchair users (IIG n=34, WLCG n=38 for between-group analysis, n=48 for combined within-group analysis) with spinal cord injury or disorder who were able to independently perform a lateral scoot transfer. INTERVENTIONS: Self-paced, web-based transfer training module. MAIN OUTCOME MEASURE: Transfer Assessment Instrument Questionnaire (TAI-Q) score at baseline, 1- and 6-months post-baseline (WLCG only), immediately post-training, and 1-month post-training. The TAI-Q is an 18-item self-assessment that covers several aspects of a quality transfer. RESULTS: The IIG significantly increased their baseline TAI-Q score from 6.91±0.98 to 7.79±1.12 (p

In the United States, people with serious illness often experience gaps and discontinuity in care. Gaps are frequently exacerbated by limited mobility, need for social support, and challenges managing multiple comorbidities. The Advanced Illness Care (AIC) Program provides nurse practitioner-led, home-based care for people with serious or complex chronic illnesses that specifically targets palliative care needs and coordinates with patients' primary care and specialty health care providers. We sought to investigate the effect of the AIC Program on hospital encounters [hospitalizations and emergency department (ED) visits], hospice conversion, and mortality.Retrospective nearest-neighbor matching.Patients in AIC who had ≥1 inpatient stay within the 60 days prior to AIC enrollment to fee-for-service Medicare controls at 9 hospitals within one health system.We matched on demographic characteristics and comorbidities, with exact matches for diagnosis-related group and home health enrollment. Outcomes were hospital encounters (30- and 90-day ED visits and hospitalizations), hospice conversion, and 30- and 90-day mortality.We included 110 patients enrolled in the AIC Program matched to 371 controls. AIC enrollees were mean age 77.0, 40.9% male, and 79.1% white. Compared with controls, AIC enrollees had a higher likelihood of ED visits at 30 [15.1 percentage points, confidence interval (CI) 4.9, 25.3; P = .004] and 90 days (27.8 percentage points, CI 16.0, 39.6; P.001); decreased likelihood of hospitalization at 30 days (11.4 percentage points, CI -17.7, -5.0; P.001); and a higher likelihood of converting to hospice (22.4 percentage points, CI 11.4, 33.3; P.001).The AIC Program provides care and coordination that the home-based serious illness population may not otherwise receive.By identifying and addressing care needs and gaps in care early, patients may avoid unnecessary hospitalizations and receive timely hospice services as they approach the end of life.

This was an investigational device observational trial with the objective to evaluate the impact of distractions on intracortical brain-computer interface (BCI) performance. Two individuals with tetraplegia had microelectrode arrays implanted into their motor cortex for trials of intracortical BCI safety and performance. The primary task was moving a robotic arm between two targets as quickly as possible, performed alone and with various secondary distraction conditions. Primary outcomes included targets acquired, path efficiency, and subjective difficulty. There was no difference in the number of targets acquired for either subject with or without distractions. Median path efficiency was similar across all conditions (range: 0.766-0.846) except the motor distraction for Subject P2, where the median path efficiency dropped to 0.675 (p = 0.033, Mann-Whitney U test). Both subjects rated the overall difficulty of the task with and without distractions as low. Overall, intracortical BCI performance was robust to various distractions.

OBJECTIVE: To investigate the changes in total internet and mobile internet use over time and determine how demographic characteristics are related to changes in internet and mobile internet use among individuals with spinal cord injury (SCI). DESIGN: Cross-sectional analysis of multicenter cohort study. SETTING: National SCI Database. PARTICIPANTS: Persons with traumatic SCI with follow-up data collected between 2012 and 2018 (n=13,622). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURE: Proportion of sample reporting internet use at all or through a mobile device over time and specifically in 2018. RESULTS: The proportion of internet users increased from 77.7% in 2012 to 88.1% in 2018. Older participants (p

Objective To investigate residential mobility among community-living adults with spinal cord injury (SCI) and the individual, health, and neighborhood factors associated with the propensity to relocate. Design Retrospective analysis of data from the National SCI Model Systems (SCIMS) Database collected between 2006 and 2018 and linked with the American Community Survey 5-year estimates. Setting Community. Interventions Not applicable. Participants People with traumatic SCI (N=4599) who participated in 2 waves of follow-up and had residential geographic identifiers at the census tract level. Main Outcome Measures Moving was a binary measure reflecting change in residential locations over a 5-year interval. Move distance distinguished nonmovers from local movers (different tracts within the same county) and long-distance movers (to different county or state). Move quality included 4 categories: stayed/low poverty tract, stayed/high poverty tract, moved/low poverty tract, and moved/high poverty tract. Results One in 4 people moved within a 5-year interval (n=1175). Of the movers, 55% relocated to a different census tract within the same county and 45% relocated to a different county or state. Thirty-five percent of all movers relocated to a high poverty census tract. Racial and ethnic minorities, people from low-income households, and younger adults were more likely to move, move locally, and relocate to a high poverty neighborhood. High poverty and racial/ethnic segregation in the origin neighborhood predicted an increased risk for remaining in or moving to a high poverty neighborhood. Conclusions Although people with SCI relocated at a lower rate than has been reported in the general population, moving was a frequent occurrence postinjury. People from vulnerable groups were more likely to remain in or relocate to socioeconomically disadvantaged neighborhoods, thus increasing the risk for health disparities and poorer long-term outcomes among minorities and people from low-income households. These findings inform policy makers’ considerations of housing, health care, and employment initiatives for individuals with SCI and other chronic disabilities.

Objectives: To evaluate the psychometric properties of the Transfer Assessment Instrument Questionnaire (TAI-Q), a self-assessment measure to evaluate transfer quality compared with clinician-reported measures. Design: Participants self-assessed transfers from their wheelchair to a mat table using the TAI-Q. For session 1, participants self-assessed their transfer both before and after reviewing a video of themselves completing the transfer (session 1). Self-assessment was completed for another transfer after a 10-minute delay (session 2, intrarater reliability) and after a 1- to 2-day delay (session 3, test-retest reliability). Self-assessment was compared with a criterion standard of an experienced clinician scoring the same transfers with the Transfer Assessment Instrument (TAI) version 4.0 (concurrent validity). Setting: 2017 National Veterans Wheelchair Games. Participants: Convenience sample of full-time wheelchair users (N=44). Interventions: Not applicable. Main Outcome Measures: TAI-Q and TAI. Results: After video review of their transfer, acceptable levels of reliability were demonstrated for total TAI-Q score for intrarater (intraclass correlation [ICC], 0.627) and test-retest reliability (ICC, 0.705). Moderate to acceptable concurrent validity was demonstrated with the TAI (ICC, 0.554-0.740). Participants tended to underestimate the quality of their transfer (reported more deficient items) compared with the TAI. However, this deficit decreased and reliability improved from pre-video review to post-video review and from session 1 to session 2. The minimum detectable change indicated that a change of 1.63 to 2.21 in the TAI-Q total score is needed to detect a significant difference in transfer skills. Conclusions: When paired with video review, the TAI-Q demonstrates moderate to acceptable levels of reliability and validity for the total score. Self-assessment was completed quickly (

Objective To determine if functional measures of ambulation can be accurately classified using clinical measures; demographics; personal, psychosocial, and environmental factors; and limb accelerations (LAs) obtained during sleep among individuals with chronic, motor incomplete spinal cord injury (SCI) in an effort to guide future, longitudinal predictions models. Design Cross-sectional, 1-5 days of data collection. Setting Community-based data collection. Participants Adults with chronic (>1 year), motor incomplete SCI (N=27). Interventions Not applicable. Main Outcome Measures Ambulatory ability based on the 10-m walk test (10MWT) or 6-minute walk test (6MWT) categorized as nonambulatory, household ambulator (0.01-0.44 m/s, 1-204 m), or community ambulator (>0.44 m/s, >204 m). A random forest model classified ambulatory ability using input features including clinical measures of strength, sensation, and spasticity; demographics; personal, psychosocial, and environmental factors including pain, environmental factors, health, social support, self-efficacy, resilience, and sleep quality; and LAs measured during sleep. Machine learning methods were used explicitly to avoid overfitting and minimize the possibility of biased results. Results The combination of LA, clinical, and demographic features resulted in the highest classification accuracies for both functional ambulation outcomes (10MWT=70.4%, 6MWT=81.5%). Adding LAs, personal, psychosocial, and environmental factors, or both increased the accuracy of classification compared with the clinical/demographic features alone. Clinical measures of strength and sensation (especially knee flexion strength), LA measures of movement smoothness, and presence of pain and comorbidities were among the most important features selected for the models. Conclusions The addition of LA and personal, psychosocial, and environmental features increased functional ambulation classification accuracy in a population with incomplete SCI for whom improved prognosis for mobility outcomes is needed. These findings provide support for future longitudinal studies that use LA; personal, psychosocial, and environmental factors; and advanced analyses to improve clinical prediction rules for functional mobility outcomes.

Objective To investigate the frequency and consequences of wheelchair repairs, looking at the relationship to usage, components, out-of-pocket costs, number of days affecting the user, and factors associated with the need for repairs or consequences. Design Survey, cross-sectional. Setting Nine spinal cord injury (SCI) Model Systems centers. Participants Wheelchair users with SCI (N=533). Interventions Not applicable. Main Outcome Measures Cost and incidence of wheelchair repairs and consequences and wheelchair usage within the past 6 months. Results A total of 310 participants (56%) reported repairs, 127 (42%) of whom experienced at least 1 adverse consequence lasting a median of 5 days (interquartile range [IQR], 2-17.3 days). Repair rates were highest for the seating system, electronics, and tires. Participants were most often stranded at home or forced to use a backup chair. Median out-of-pocket costs were $150 (IQR, $50-$620). Active users, based on type of mobility and terrain, experienced more repairs and consequences than less active users. Repairs were more common among those who were Black (odds ratio [OR], 2.42) or power wheelchair (PWC) users (OR, 1.84), whereas consequences were more common among those who were Black (OR, 2.27), PWC (OR, 2.08) or power assist users (OR, 2.76), and those who had public insurance (OR, 1.70). Conclusions Wheelchair repairs continue to affect more than 50% of wheelchair users with significant financial and personal cost. High repair rates limited participation inside and outside of the home. Consequences lasted longer than 2 weeks for many and may be minimized by a working backup chair. Disparities exist based on participant and wheelchair factors; repairs and adverse consequences appear to hit those most vulnerable with the least financial resources. Costs may be a barrier to repair completion for some individuals. This ongoing problem of high repair rates and their associated effects requires action such as higher standards, access to quicker service, and better training of users on wheelchair maintenance and repair.

Intracortical brain-computer interfaces (iBCI) have the potential to restore independence for individuals with significant motor or communication impairments. One of the most realistic avenues for clinical translation of iBCI technology is to enable control of a computer cursor—i.e. movement-related neural activity is interpreted (decoded) and used to drive cursor function. Both nonhuman primate and human studies have demonstrated high-level cursor translation control using attempted upper limb reaching movements. However, cursor click control—based on identifying attempted grasp—has only been successful in providing discrete click functionality; the ability to maintain click during translation does not yet exist. Here we present a novel decoding approach for cursor click based on identifying transient neural responses that emerge at the onset and offset of intended hand grasp. We demonstrate in a human participant, who used the BCI system independently in his home, that this transient-based approach provides high-functioning, generalized click control that can be used for both point-and-click and click-and-drag applications.

Purpose Investigate the type and frequency of wheelchair repairs and resulting adverse consequences in a Veteran population. Design Convenience cross-sectional sample survey. Setting Data were collected at the 2017 National Veterans Wheelchair Games. Participants Veterans who use a wheelchair ≥ 40 h/wk (n = 60). Intervention Not applicable. Main outcome measures Repairs and associated adverse consequences, wheelchair age and usage, type of repairs completed, time elapsed between breakdowns and repairs, and who completed repairs. Results 60 participants reported 124 repairs in the previous 6 months with 88.3% of participants requiring at least one repair. Consequences were reported by 43.5% of those experiencing repairs and were most commonly secondary to repairs in the electrical system, wheelchair frame, power/control system, and wheels and casters. Travelling greater distances during the week and on weekends was associated with increased rates of repairs (p = 0.01 and p = 0.02, respectively) and consequences (p = 0.03 and p = 0.03, respectively). Power wheelchairs were more likely to require repairs than manual wheelchairs (p = 0.007). The median time to repair was 7 [0.8,30] days. Vendors completed 82.1% of the repairs. Those experiencing longer repair times were more likely to experience adverse consequences (p Conclusion A high number of repairs and resulting adverse consequences occur for wheelchair users, particularly power wheelchair users, in a sample of Veterans. Interventions to prevent breakdowns and to address repairs and adverse consequences in a time-efficient manner are needed. Implications for rehabilitation In a sample of Veterans, a high number of repairs and resulting adverse consequences occur for wheelchair users, particularly power wheelchair users. There is an important clinical opportunity to help wheelchair users avoid repairs in the first place and reduce adverse consequences after breakdowns occur by improving wheelchair quality, providing preventative chair maintenance, and repairing breakdowns in a timely and efficient manner. These interventions may prove impactful in reducing the adverse medical, functional, and social consequences of wheelchair breakdowns.

SummaryMicrostimulation in the somatosensory cortex can evoke artificial tactile percepts and can be incorporated into bidirectional brain-computer interfaces (BCIs) to restore function after injury or disease. However, little is known about how stimulation parameters themselves affect perception. Here, we stimulated through microelectrode arrays implanted in the somatosensory cortex of a human participant with a cervical spinal cord injury and varied the stimulus amplitude, duration, and frequency. Increasing the amplitude and duration increased the perceived intensity on all tested electrodes. Surprisingly, we found that increasing the frequency evoked more intense percepts on some electrodes but evoked less intense percepts on most electrodes. Electrodes divided into three groups which evoked distinct perceptual qualities that depended on the stimulus frequency and were spatially organized in cortex. These results contribute to our growing understanding of the structure and function of the somatosensory cortex and will facilitate principled development of stimulation strategies for bidirectional BCIs.

Restoring somatosensory feedback to people with limb amputations is crucial to improve prosthetic control. Multiple studies have demonstrated that peripheral nerve stimulation and targeted reinnervation can provide somatotopically relevant sensory feedback. While effective, the surgical procedures required for these techniques remain a major barrier to translatability. Here, we demonstrate in four people with upper-limb amputation that epidural spinal cord stimulation (SCS), a common clinical technique to treat pain, evoked somatosensory percepts that were perceived as emanating from the missing arm and hand. Over up to 29 days, stimulation evoked sensory percepts in consistent locations in the missing hand regardless of time since amputation or level of amputation. Evoked sensations were occasionally described as naturalistic (e.g. touch or pressure), but were often paresthesias. Increasing stimulus amplitude increased the perceived intensity linearly, without increasing area of the sensations. These results demonstrate the potential of SCS as a tool to restore somatosensation after amputations., eLife digest Even some of the most advanced prosthetic arms lack an important feature: the ability to relay information about touch or pressure to the wearer. In fact, many people prefer to use simpler prostheses whose cables and harnesses pass on information about tension. However, recent studies suggest that electrical stimulation might give prosthesis users more sensation and better control. After an amputation, the nerves that used to deliver sensory information from the hand still exist above the injury. Stimulating these nerves can help to recreate sensations in the missing limb and improve the control of the prosthesis. Still, this stimulation requires complicated surgical interventions to implant electrodes in or around the nerves. Spinal cord stimulation – a technique where a small electrical device is inserted near the spinal cord to stimulate nerves – may be an easier alternative. This approach only requires a simple outpatient procedure, and it is routinely used to treat chronic pain conditions. Now, Chandrasekaran, Nanivadekar et al. show that spinal cord stimulation can produce the feeling of sensations in a person’s missing hand or arm. In the experiments, four people who had an arm amputation underwent spinal cord stimulation over 29 days. During the stimulation, the participants reported feeling electrical buzzing, vibration, or pressure in their missing limb. Changing the strength of the electric signals delivered to the spinal cord altered the intensity of these sensations. The experiments are a step toward developing better prosthetics that restore some sensation. Further studies are now needed to determine whether spinal cord stimulation would allow people to perform sensory tasks with a prosthetic, for example handling an object that they cannot see.

The growing field of regenerative rehabilitation has great potential to improve clinical outcomes for individuals with disabilities. However, the science to elucidate the specific biological underpinnings of regenerative rehabilitation-based approaches is still in its infancy and critical questions regarding clinical translation and implementation still exist. In a recent roundtable discussion from International Consortium for Regenerative Rehabilitation stakeholders, key challenges to progress in the field were identified. The goal of this article is to summarize those discussions and to initiate a broader discussion among clinicians and scientists across the fields of regenerative medicine and rehabilitation science to ultimately progress regenerative rehabilitation from an emerging field to an established interdisciplinary one. Strategies and case studies from consortium institutions-including interdisciplinary research centers, formalized courses, degree programs, international symposia, and collaborative grants-are presented. We propose that these strategic directions have the potential to engage and train clinical practitioners and basic scientists, transform clinical practice, and, ultimately, optimize patient outcomes.

While recent advances in intracortical brain-computer interfaces (iBCI) have demonstrated the ability to restore motor and communication functions, such demonstrations have generally been confined to controlled experimental settings and have required bulky laboratory hardware. Here, we developed and evaluated a self-contained portable iBCI that enabled the user to interact with various computer programs. The iBCI, which weighs 1.5 kg, consists of digital headstages, a small signal processing hub, and a tablet PC. A human participant tested the portable iBCI in laboratory and home settings under an FDA Investigational Device Exemption (NCT01894802). The participant successfully completed 96% of trials in a 2D cursor center-out task with the portable iBCI, a rate indistinguishable from that achieved with the standard laboratory iBCI. The participant also completed a variety of free-form tasks, including drawing, gaming, and typing.

PURPOSE Many medical schools require scholarly research projects. However, outcomes data from these initiatives are scarce. The authors studied the impact of the Scholarly Research Project (SRP), a four-year longitudinal requirement for all students at the University of Pittsburgh School of Medicine (UPSOM), on research productivity and residency match. METHOD The authors conducted a longitudinal study of non-dual-degree UPSOM graduates in 2006 (n = 121, non-SRP participants) versus 2008 (n = 118), 2010 (n = 106), and 2012 (n = 132), all SRP participants. The authors used PubMed for publication data, National Resident Matching Program for residency match results, and Blue Ridge Institute for Medical Research for National Institutes of Health funding rank for residency-affiliated academic institutions. RESULTS Research productivity of students increased for those completing the SRP, measured as a greater proportion of students with publications (27.3% in 2006 vs. 45.8% in 2008, 55.7% in 2010, and 54.5% in 2012; P < .001) and first-authorship (9.9% in 2006 vs. 26.3% in 2008, 33.0% in 2010, and 35.6% in 2012; P < .001). Across years, there was a significantly greater proportion of students with peer-reviewed publications matched in higher-ranked residency programs (57.0% with publications in the top 10%, 52.7% in the top 10%-25%, 32.4% in the top 25%-50%, 41.2% in the bottom 50%, and 45.2% in unranked programs; P = .018). CONCLUSIONS Longitudinal research experiences for medical students may be one effective tool in fostering student publications and interest in extending training in a research-focused medical center.

Objectives To investigate the relation of gait training (GT) during inpatient rehabilitation (IPR) to outcomes of people with traumatic spinal cord injury (SCI). Design Prospective observational study using the SCIRehab database. Setting Six IPR facilities. Participants Patients with new SCI (N=1376) receiving initial rehabilitation. Interventions Patients were divided into groups consisting of those who did and did not receive GT. Patients were further subdivided based on their primary mode of mobility as measured by the FIM. Main Outcome Measures Pain rating scales, Patient Health Questionnaire Mood Subscale, Satisfaction With Life Scale, and Craig Handicap Assessment and Reporting Technique (CHART). Results Nearly 58% of all patients received GT, including 33.3% of patients who were primarily using a wheelchair 1 year after discharge from IPR. Those who used a wheelchair and received GT, received significantly less transfer and wheeled mobility training ( P P =.002), mobility ( P =.024), and occupation ( P =.003) scores were significantly worse in patients who used a wheelchair at 1 year and received GT, compared with those who used a wheelchair and did not receive GT in IPR. Older age was also a significant predictor of worse participation as measured by the CHART. Conclusions A significant percentage of individuals who are not likely to become functional ambulators are spending portions of their IPR stays performing GT, which is associated with less time allotted for other functional interventions. GT in IPR was also associated with participation deficits at 1 year for those who used a wheelchair, implying the potential consequences of opportunity costs, pain, and psychological difficulties of receiving unsuccessful GT. Clinicians should consider these data when deciding to implement GT during initial IPR.

Using proper technique is important for minimizing upper limb kinetics during wheelchair transfers. The objective of the study was to 1) evaluate the transfer techniques used during toilet transfers and 2) determine the impact of technique on upper limb joint loading for two different toilet configurations.Twenty-six manual wheelchair users (23 men and 3 women) performed transfers in a side and front wheelchair-toilet orientation while their habitual transfer techniques were evaluated using the Transfer Assessment Instrument. A motion analysis system and force sensors were used to record biomechanical data during the transfers.More than 20% of the participants failed to complete five transfer skills in the side setup compared to three skills in the front setup. Higher quality skills overall were associated with lower peak forces and moments in both toilet configurations (-0.68 r -0.40, p 0.05). In the side setup, participants who properly placed their hands in a stable position and used proper leading handgrips had lower shoulder resultant joint forces and moments than participants who did not perform these skills correctly (p ≤ 0.04). In the front setup, positioning the wheelchair within three inches of the transfer target was associated with reduced peak trailing forces and moments across all three upper limb joints (p = 0.02).Transfer skills training, making toilet seats level with the wheelchair seat, positioning the wheelchair closer to the toilet and mounting grab bars in a more ideal location for persons who do sitting pivot transfers may facilitate better quality toilet transfers.

Brain-computer interface (BCI) controlled prosthetic arms are being developed to restore function to people with upper-limb paralysis. This work provides an opportunity to analyze human cortical activity during complex tasks. Previously we observed that BCI control became more difficult during interactions with objects, although we did not quantify the neural origins of this phenomena. Here, we investigated how motor cortical activity changed in the presence of an object independently of the kinematics that were being generated using intracortical recordings from two people with tetraplegia. After identifying a population-wide increase in neural firing rates that corresponded with the hand being near an object, we developed an online scaling feature in the BCI system that operated without knowledge of the task. Online scaling increased the ability of two subjects to control the robotic arm when reaching to grasp and transport objects. This work suggests that neural representations of the environment, in this case the presence of an object, are strongly and consistently represented in motor cortex but can be accounted for to improve BCI performance.

Research Objectives To assess the sensitivity, specificity, and accuracy of selected physical examination procedures in identifying supraspinatus tears using magnetic resonance imaging (MRI) as a reference criteria in wheelchair users with chronic paraplegia. Design Cross-sectional. Setting Three SCI Model Systems (SCIMS) Centers. Participants 62 full-time manual wheelchair users with chronic paraplegia (104 shoulders; average age 41.1±11.7; average injury duration 12.5±9.9; average BMI 25.4±9.9; 19.4% female). Interventions N/A. Main Outcome Measures Presence or absence of supraspinatus tears, diagnosed by MRI[1]; physical examinations for supraspinatus pathology, including supraspinatus palpation over the greater tuberosity[2], painful arc[3], Neer's test[4], Jobe's test[5], and resisted external rotation (ER); diagnostic statistics including sensitivity, specificity, positive and negative likelihood ratios, positive and negative predictive values. A receiver operating characteristic (ROC) curve was generated to determine the area under the curve [AUC]. Results A positive Jobe's test, greater tuberosity palpation, and resisted ER produced the highest positive likelihood ratios (between 3.0 and 4.1), yet sensitivities were low (0.33-0.50). The ROC curve suggested the optimal threshold to detect a supraspinatus tear was one or more of the following positive tests: Jobe's, tendon palpation, ER, painful arc (sensitivity=0.67, specificity=0.074). The ROC curve with these four tests yielded an AUC of 0.72. When Neer's was included, the AUC was 0.70. Conclusions The findings from this study indicate no single test was best to screen for supraspinatus tears in this sample. Presence of one or more positive physical examination tests yielded the best accuracy. The low prevalence of tears among this sample could have negatively affect the power to determine sensitivity. Future studies should aim to include a larger proportion of individuals with tears to better determine sensitivity of the tests. Author(s) Disclosures The authors have nothing to disclose.

OBJECTIVE: Intracortical microstimulation (ICMS) in somatosensory cortex can restore sensation to people with spinal cord injury or other conditions. One potential challenge for chronic ICMS is whether neural recording and stimulation can remain stable over many years. This is particularly relevant since the recording quality from implanted microelectrode arrays can degrade over time and limitations in stimulation longevity have been considered a potential barrier to the clinical use of ICMS. Our objective was to evaluate recording stability on intracortical stimulated sputtered iridium oxide (SIROF) and non-stimulated platinum electrodes in somatosensory and motor cortex in a human participant across a long period of implantation. Additionally, we measured how ICMS was able to evoke sensations over time. APPROACH: In a study investigating intracortical implants for a bidirectional brain-computer interface, we implanted microelectrode arrays with SIROF tips in the somatosensory cortex of a human participant with a cervical spinal cord injury. We regularly stimulated these electrodes to evoke tactile sensations on the hand. Here, we quantify the stability of these electrodes in comparison to non-stimulated platinum electrodes implanted in the motor cortex over 1500 days in two ways: recorded signal quality and electrode impedances. Additionally, we quantify the perceptual stability of ICMS-evoked sensations using detection thresholds. MAIN RESULTS: We found that recording quality, as assessed by the number of electrodes with high-amplitude waveforms (> 100 μV peak-to-peak), peak-to-peak voltage, noise, and signal-to-noise ratio, generally decreased over time on stimulated SIROF and non-stimulated platinum electrodes. However, stimulated SIROF electrodes were much more likely to continue to record high-amplitude signals than non-stimulated platinum electrodes. Interestingly, the detection thresholds for stimulus-evoked tactile sensations decreased over time from a median of 31.5 μA at day 100 to 10.4 μA at day 1500, with the most substantial changes occurring between day 100 and 500. SIGNIFICANCE: These results provide evidence that ICMS in human somatosensory cortex can be provided over long periods of time without deleterious effects on recording or stimulation capabilities. In fact, the sensitivity to stimulation improved over time.

Objectives To assess in Veterans with spinal cord injury (SCI) or amputated limb (AL) the following: (1) patient demographics, medical factors, cultural and psychosocial characteristic by race; (2) wheelchair quality by race; and (3) the independent associations of patient race and the other factors with wheelchair quality. Design Cross-sectional cohort study. Setting Three Department of Veterans Affairs (VA) medical centers affiliated with academic medical centers. Participants Eligible participants were Veterans with SCI or ALs (N=516); 482 of them completed the interview. Analyses were restricted to white and African American participants. Because there was no variation in wheelchair quality among AL patients (n=42), they were excluded from all but descriptive analyses, leading to a final sample size of 421. Interventions Not applicable. Main Outcome Measure Wheelchair quality as defined by the Medicare Healthcare Common Procedure Coding System. Results We found race differences in many of our variables, but not in quality for manual (odds ratio [OR]=.67; 95% confidence interval [CI], .33–1.36) or power (OR=.82; 95% CI, .51–1.34) wheelchairs. Several factors including age (OR=.96; 95% CI, .93–.99) and income (OR=3.78; 95% CI, 1.43–9.97) were associated with wheelchair quality. There were no significant associations of cultural or psychosocial factors with wheelchair quality. Conclusions Although there were no racial differences in wheelchair quality, we found a significant association of older age and lower income with poorer wheelchair quality among Veterans. Efforts are needed to raise awareness of such disparities among VA wheelchair providers and to take steps to eliminate these disparities in prescription practice across VA sites.

As Brain-Computer Interface (BCI) systems advance for uses such as robotic arm control it is postulated that the control paradigms could apply to other scenarios, such as control of video games, wheelchair movement or even flight. The purpose of this pilot study was to determine whether our BCI system, which involves decoding the signals of two 96-microelectrode arrays implanted into the motor cortex of a subject, could also be used to control an aircraft in a flight simulator environment. The study involved six sessions in which various parameters were modified in order to achieve the best flight control, including plane type, view, control paradigm, gains, and limits. Successful flight was determined qualitatively by evaluating the subject's ability to perform requested maneuvers, maintain flight paths, and avoid control losses such as dives, spins and crashes. By the end of the study, it was found that the subject could successfully control an aircraft. The subject could use both the jet and propeller plane with different views, adopting an intuitive control paradigm. From the subject's perspective, this was one of the most exciting and entertaining experiments she had performed in two years of research. In conclusion, this study provides a proof-of-concept that traditional motor cortex signals combined with a decoding paradigm can be used to control systems besides a robotic arm for which the decoder was developed. Aside from possible functional benefits, it also shows the potential for a new recreational activity for individuals with disabilities who are able to master BCI control.

Restoring somatosensory feedback to people with limb amputations is crucial for improving prosthesis acceptance and function. Epidural spinal cord stimulation is a commonly used clinical procedure that targets sensory neural pathways in the dorsal spinal cord to treat pain conditions. A similar approach could be developed as a clinically translatable means to restore somatosensation in amputees. We show that epidural stimulation of the dorsal spinal cord evoked sensory percepts, perceived as emanating from the amputated arm and hand, in four people with upper-limb amputation. After an initial caudal movement immediately following the implantation, the leads stabilized, exhibiting a median migration of

Motor commands for the arms and hands generally originate in contralateral motor cortex anatomically. However, ipsilateral primary motor cortex shows activity related to arm movement despite the lack of direct connections. The extent to which the activity related to ipsilateral movement is independent from that related to contralateral movement is unclear based on conflicting conclusions in prior work. Here we present the results of bilateral arm and hand movement tasks completed by two human subjects with intracortical microelectrode arrays implanted in left primary motor cortex for a clinical brain-computer interface study. Neural activity was recorded while they attempted to perform arm and hand movements in a virtual environment. This enabled us to quantify the strength and independence of motor cortical activity related to continuous movements of each arm. We also investigated the subjects’ ability to control both arms through a brain-computer interface system. Through a number of experiments, we found that ipsilateral arm movement was represented independently of, but more weakly than, contralateral arm movement. However, the representation of grasping was correlated between the two hands. This difference between hand and arm representation was unexpected, and poses new questions about the different ways primary motor cortex controls hands and arms.