A study on the formative usability testing for modular powered wheelchair.

The increasing prevalence of mobility impairments underscores the urgent need for accessible and affordable mobility aids. To overcome the mobility limitations of people with disabilities, there is an increasing need for the development of lightweight and portable powered wheelchairs that can be easily loaded. This study aimed to perform an early health technology assessment and a formative usability evaluation on a modular (detachable) powered wheelchair. It aimed to gauge device satisfaction among users, pinpoint areas for improvement, and detect any unforeseen errors to inform future development. Engaging 16 participants, including powered wheelchair users, healthcare professionals, and caregivers, the research evaluated the wheelchair's functionality in various scenarios, emphasizing safety, effectiveness, and convenience. Statistical analyses of task performance and satisfaction surveys highlighted that, while powered wheelchair users successfully completed tasks focusing on driving and power control, healthcare professionals and caregivers encountered difficulties with the wheelchair's assembly and disassembly. Despite general positivity, the surveys indicated mixed satisfaction levels regarding safety, validity, and convenience, with specific issues related to frame durability, seat comfort, and control mechanisms. These findings suggest that refining the wheelchair's design and addressing user concerns could significantly enhance satisfaction and mobility services. Future efforts will include a thorough review of an advanced prototype and further satisfaction assessments.

We believe that our study makes a significant contribution to the literature by addressing a critical gap in the understanding of user-centric design and usability testing for powered wheelchairs.By emphasizing the importance of early assessments and incorporating user feedback into the development process, our research offers practical insights for creating more accessible and user-friendly mobility solutions.This contribution is particularly relevant in the context of advancing assistive technology and improving the quality of life for individuals with disabilities.

Customised joystick-making and training service of power wheelchair using rapid prototyping in rehabilitation centre for people with cervical spinal cord injury: findings from two case studies.

PURPOSE: This study aimed to evaluate the clinical applicability of a customised power wheelchair joystick using rapid prototyping with 3D modeling and printing technology within a rehabilitation centre for patients with cervical spinal cord injury. MATERIALS AND METHODS: Two male participants with tetraplegia following cervical-level spinal cord injury who had difficulty operating a powered wheelchair were recruited. The procedure of the joystick-making and training service consists of four steps: (1) driving evaluation; (2) digital fabrication; (3) functional test; and (4) driving training. K-QUEST 2.0 (Korean-Quebec User Evaluation of Satisfaction version 2.0) was used to measure the usability of the off-the-shelf and customised joystick. RESULTS: During the application process, several redesign stages were required to obtain the final customised joystick. After participants attended a 30-min driving training five times per week for 8 weeks, the usability of the customised joystick was higher than that of the off-the-shelf one. CONCLUSION: Providing the customised joystick-making and training service can be used in hospitalised rehabilitation centre before the hospital discharge of patients and returns to their everyday lives.

3D printing technology in rehabilitation clinics can provide new benefits, including cost-effectiveness, customisation of assistive devices, higher productivity, and enhanced collaboration with clients. More specifically, the entire intervention process, from medical evaluation, designing and manufacturing the devices, and training the client, can be performed efficiently and quickly by rehabilitation practitioners who best understand the client's characteristics.This study aimed to confirm the clinical applicability of a quick and efficient service for a customised power wheelchair joystick using 3D modelling and printing technology in rehabilitation centres for patients with cervical spinal cord injury. This study is expected to provide clinical support for connecting potential users and practitioners with technological advancements.

Comparison of Trends in the Incidence of Traumatic Spinal Cord Injury in Daily Life, Automobile Accidents, and Industrial Accidents: A National Multi-Insurance Study in Korea.

BACKGROUND: To examine the incidence of traumatic spinal cord injury (TSCI) from all etiologies, we measured and compared the incidence of TSCI from three national or quasi-national databases in South Korea, namely, the National Health Insurance Service (NHIS), automobile insurance (AUI), and Industrial Accident Compensation Insurance (IACI). METHODS: We reviewed patients with TSCI reported in the NHIS database between 2009 and 2018, and in the AUI and IACI databases between 2014 and 2018. TSCI patients were defined as those first admitted to the hospital with a diagnosis of TSCI according to the International Classification of Diseases (10th revision) criteria. Age-adjusted incidence was calculated using direct standardization using the 2005 South Korean population or the 2000 US population as the standard population. The annual percentage changes (APC) of TSCI incidence were calculated. The Cochrane-Armitage trend test was performed according to the injured body region. RESULTS: In the NHIS database, age-adjusted TSCI incidence using the Korean standard population increased significantly from 2009 to 2018 (from 33.73 per million in 2009 to 38.14 per million in 2018, APC = 1.2%, P = 0.014). Contrarily, age-adjusted incidence in the AUI database significantly decreased from 13.88 per million in 2014 to 11.57 per million in 2018 (APC = - 5.1%, P = 0.009). In the IACI database, the age-adjusted incidence showed no significant difference, while crude incidence showed a significant increase (from 22.02 per million in 2014 to 28.92 per million in 2018, APC = 6.1%, P = 0.038). According to the age group, all the three databases showed high incidences of TSCI in those in their 60s and 70s or older. Among those in their 70s or older, the incidence of TSCI increased dramatically in the NHIS and IACI databases, while no significant trend was found in AUI database. In 2018, the number of TSCI patients was the highest among those over 70 years of age in the NHIS, whereas among those in their 50s were the highest in both AUI and IACI. The proportion of patients with cervical spinal cord injury was the most common in all these databases. CONCLUSIONS: The differences in trends in the incidence of TSCI may be due to the different etiologies and different characteristics of subjects depending on insurance type. These results imply the need for tailored medical strategies for the different injury mechanisms represented by three national insurance services in South Korea.

Frequency and Cost of Claims by Injury Type From the Korea Workers' Compensation Insurance Between 2016 and 2019.

OBJECTIVE: This study aimed to examine the frequency of worker injuries by affected body part(s) and the associated costs. Methods : We performed a secondary analysis of national workers' compensation claims data from the Korean workers' compensation insurance. The main outcome measures were frequency and cost of claims by injury type. Results : Multiple injuries were ranked as the highest injury type in the number of annual claims and percentage of the total cost/total medical cost. Hand/wrist/finger was the most common single-injury type. The frequency of injury type and the cost amount payable as a percentage of the total cost were the highest for multiple injuries, hand/wrist/finger injuries, and knee/lower leg injuries. Conclusions : Regarding frequency and costs, hand/wrist/finger injuries were highest in cost, by single-injury type. Therefore, these injuries should be recognized as intervention targets.

Functional improvement by body-powered 3D-printed prosthesis in patients with finger amputation: Two case reports.

RATIONALE: The most common upper limb amputations are finger amputations, resulting in functional limitations that lead to problems with activities of daily living or job loss. For many years, prosthetic options for finger amputations have been limited to passive prostheses. In many countries including South Korea, body-powered finger prostheses have rarely been prescribed due to high cost, lack of experience of physicians and prosthetists, low interest and no coverage by insurance benefits. We report 2 cases of work-related finger amputations in patients who received body-powered 3D-printed finger prostheses. PATIENT CONCERNS AND DIAGNOSIS: Patient 1 was a 25-year-old woman with second and third finger amputations at the proximal interphalangeal level. Patient 2 was a 26-year-old man who sustained a second finger amputation at proximal interphalangeal level. INTERVENTIONS: We created body-powered 3D-printed finger prostheses that mimicked distal interphalangeal joint motion through patient-driven metacarpophalangeal joint motion using a string connected to a wrist strap and a linkage system. The source code "Knick Finger" was downloaded from e-NABLE. OUTCOMES: After 1 month of prosthesis training, both patients were satisfied with the prostheses and showed improved performance in patient-derived goals of cooking (patient 1) and typing on a computer (patient 2). LESSONS: Over the past decade, significant advances have been made in 3D-printed prosthetics owing to their light weight, low cost, on-site fabrication, and easy customization. Although there are still several limitations in the general application of 3D-printed finger prostheses, our study suggests that for patients with finger amputations, body-powered 3D-printed finger prostheses have high potential as an additional prosthetic option to the existing passive cosmetic prostheses.

Efficacy of a Lower Back Intensive Rehabilitation Program in Occupational Injury Patients and Characteristics of Care: A Retrospective Cohort Study.

BACKGROUND The Lower Back Intensive Rehabilitation Program (LBIRP) was developed by hospitals affiliated with the Korea Workers' Compensation and Welfare Service to support patients with lower back pain caused by occupational injuries. We studied the characteristics of patients who participated in this program to assess its efficacy and suggest areas for program quality improvement. MATERIAL AND METHODS This large-scale retrospective cohort study analyzed the electronic medical records and occupational injury insurance data of patients with lower back damage due to occupational injuries who participated in the LBIRP in hospitals affiliated with the Korea Workers Compensation and Welfare Service between April 2017 and 2020. RESULTS Multidimensional analysis showed that pain, isometric strength of the hip, central muscular endurance, neuromuscular control ability, and self-questionnaire scores were significantly different among groups. Further, significant differences were observed in most multidimensional analysis items according to the cause of disease, program period, and severity of disease. There were no significant differences between the groups. CONCLUSIONS Based on the findings of this study, efforts must be continued to improve and standardize the LBIRP. It is expected that future studies with continuous patient follow-up comparing treatment effects among affiliated hospitals will help to expand the LBIRP for rehabilitation in private hospitals.

Development of a Digital Healthcare Management System for Lower-Extremity Amputees: A Pilot Study.

The research, which was designed as a "pre- and post-single group" study, included patients with lower-limb amputation and aimed to evaluate the effectiveness of self-directed physical-strength training and cardiovascular exercise using a novel digital healthcare management service three times a week for 12 weeks. Muscle strength, thigh circumference, lipid profile and glycated hemoglobin levels, pulmonary function, quality of life, and physical activity level were evaluated before and after the intervention, while satisfaction was measured after the study. Among the 14 included patients, the proportion of adherence to the physical-strength training and physical-strengthening activity were 85.2% and 75.8%, respectively. The level of satisfaction with the digital healthcare management system was high. Significant changes were observed in the muscle-strength tests (dominant grip power and muscle strength of knee flexion and extension of the intact side), thigh circumference, and glycated hemoglobin levels. Further, the quality-of-life score showed improvement, although without significant differences. Individualized exercise management using the novel digital healthcare management system for lower-limb amputees could induce interest in self-care and promote physical activity and healthy behavior. Through this effect, we can expect a reduction in the incidence of cardiovascular diseases, diabetes mellitus, dyslipidemia, and severe injuries from falling.

Satisfying medical and rehabilitation needs positively influences returning to work after a work-related injury: an analysis of national panel data from 2018 to 2019.

BACKGROUND: This study examined how meeting the medical needs of injured workers after initial treatment may affect their return to work, using data from the Panel Study of Workers' Compensation Insurance. METHODS: This study was designed as a longitudinal study, which used data from the second-year, follow-up survey conducted in the secondary cohort of the Panel Study of Workers' Compensation Insurance. The odds ratio (OR) and 95% confidence interval were estimated through binomial and multinomial logistic regression analyses to examine the effects of unmet medical needs on workers' return to original work and return to work overall (including reemployment). RESULTS: The returned to original work OR of workers whose rehabilitation needs were met was 1.35 (1.12-1.63) while the return to work OR was 1.20 (1.03-1.41). The returned to original work OR of workers whose medical needs were met was 1.64 (1.18-2.27) while the return to work OR was 1.39 (1.07-1.80). In terms of disability rating, the return to work ORs of workers with mild disabilities whose medical/rehabilitation needs were not met and those of workers without disabilities were 1.71 (1.17-2.49) and 1.97 (1.27-3.08), respectively. In the case of regular/temporary workers, the returned-to-work ORs of workers whose medical/rehabilitation needs were not met were 1.54 (1.12-2.13) and 1.27 (1.03-1.56), respectively. CONCLUSIONS: For workers who sustained work-related injuries, providing medical accessibility and meeting rehabilitation needs were found to be important predictors of return to work after initial treatment.

Assessment of Dysarthria Using One-Word Speech Recognition with Hidden Markov Models.

BACKGROUND: The gold standard in dysarthria assessment involves subjective analysis by a speech-language pathologist (SLP). We aimed to investigate the feasibility of dysarthria assessment using automatic speech recognition. METHODS: We developed an automatic speech recognition based software to assess dysarthria severity using hidden Markov models (HMMs). Word-specific HMMs were trained using the utterances from one hundred healthy individuals. Twenty-eight patients with dysarthria caused by neurological disorders, including stroke, traumatic brain injury, and Parkinson's disease were participated and their utterances were recorded. The utterances of 37 words from the Assessment of Phonology and Articulation for Children test were recorded in a quiet control booth in both groups. Patients were asked to repeat the recordings for evaluating the test-retest reliability. Patients' utterances were evaluated by two experienced SLPs, and the consonant production accuracy was calculated as a measure of dysarthria severity. The trained HMMs were also employed to evaluate the patients' utterances by calculating the averaged log likelihood (aLL) as the fitness of the spoken word to the word-specific HMM. RESULTS: The consonant production accuracy reported by the SLPs strongly correlated (r = 0.808) with the aLL, and the aLL showed excellent test-retest reliability (intraclass correlation coefficient, 0.964). CONCLUSION: This leads to the conclusion that dysarthria assessment using a one-word speech recognition system based on word-specific HMMs is feasible in neurological disorders.

Determinants of Functional Outcomes Using Clinical Pathways for Rehabilitation After Hip Fracture Surgery.

BACKGROUND: This study evaluated functional outcomes using newly established clinical pathways after hip fracture surgery in older adults and analyzed the major determinants of successful functional outcomes in rehabilitation programs using standardized clinical pathways. METHODS: This was a retrospective cohort study performed in a tertiary rehabilitation facility. A total of 220 patients who had received unilateral hip fracture surgery were followed up from immediately after surgery to 6 months postoperatively. Clinical pathways for rehabilitation included early, individualized rehabilitation, education for activities of daily living, review of general medical conditions, and arrangement of discharge settings. One rehabilitation specialist consecutively checked ambulatory function using 3-level grading, and patients were classified into good recovery and poor recovery groups based on ambulatory function at 6 months postoperatively. Logistic regression analysis was performed using 7 representative variables (age, sex, bone mineral density, Mini-Mental Status Examination [MMSE], Berg Balance Scale [BBS], premorbid ambulatory function, and length of hospital stay). RESULTS: A total of 86.8% of patients could walk with or without assistance at 6 months after surgery and 75.5% of patients involved in the rehabilitation program were classified into the good recovery group in this study. the good recovery group showed higher mmse and bbs scores compared with the poor recovery group. the factors in the model most strongly correlated with recovery were mmse and bbs. CONCLUSION: This study showed that a well-designed rehabilitation program could improve ambulatory function in older patients after hip fracture surgery and that cognitive impairment and poor balance control may inhibit the recovery of ambulatory function.

Apoptosis in young and old denervated rat skeletal muscle.

INTRODUCTION: We investigated the apoptotic response to different degrees of denervation in young and older rats randomized into control (C), partial (PD), and complete denervation (CD) of muscles innervated by the sciatic nerve. METHODS: Muscle wet weight to body weight (MWW/BW), myosin heavy chain (MHC) isoforms, and fiber cross-sectional area were determined in gastrocnemius and soleus muscles. Apoptotic responses were determined by changes in myonuclei and expression of Bcl-2 and BAX. RESULTS: PD and CD resulted in significant reductions in MWW/BW and FCSA in both young and older rats. Older controls had greater apoptotic responses than young controls. Apoptotic responses were greater in PD and CD than in C in both age groups. No statistical interaction between denervation and age group was seen. CONCLUSIONS: Older age was associated with increased level of apoptosis, but older muscle was not more vulnerable to the effect of denervation. Muscle Nerve 55: 262-269, 2017.

The Impact of Acute Phase Domain-Specific Cognitive Function on Post-stroke Functional Recovery.

OBJECTIVE: To assess whether the cognitive function in the acute stage evaluated by domain-specific neuropsychological assessments would be an independent predictor of functional outcome after stroke. METHODS: Forty patients underwent 4 domain-specific neuropsychological examinations about 3 weeks after the onset of stroke. The tests included the Boston Naming Test (BNT), the construction recall test (CRT), the construction praxis test (CPT), and the verbal fluency test (VFT). The Korean version of Modified Barthel Index (K-MBI) at 3 months and the modified Rankin Scale (mRS) at 6 months were investigated as functional outcome after stroke. Functional improvement was assessed using the change in K-MBI during the first 3 months and subjects were dichotomized into 'good status' and 'poor status' according to mRS at 6 months. The domain-specific cognitive function along with other possible predictors for functional outcome was examined using regression analysis. RESULTS: The z-score of CPT (p=0.044) and CRT (p<0.001) were independent predictors for functional improvement measured by the change in K-MBI during the first 3 months after stroke. The z-score of CPT (p=0.049) and CRT (p=0.048) were also independent predictors of functional status at post-stroke 6 months assessed by mRS. CONCLUSION: Impairment in visuospatial construction and memory within one month after stroke can be an independent prognostic factor of functional outcome. Domain-specific neuropsychological assessments could be considered in patients with stroke in the acute phase to predict long-term functional outcome.

Correlates of bone mineral density and sagittal spinal balance in the aged.

OBJECTIVE: To investigate the relationship between bone mineral density (BMD) and sagittal spinal balance in the Korean elderly population. METHODS: The retrospective study included subjects aged 60 years and above, who had whole-spine lateral radiography and dual-energy X-ray absorptiometry (DEXA) within a year's gap between each other. Sagittal vertical axis (SVA) for evaluation of sagittal spinal balance and five spinopelvic parameters were measured through radiography. The presence of compression fracture was identified. Correlations of BMD T-scores with SVA and with the spinopelvic parameters were assessed using Pearson correlation coefficient (PCC). Linear regression analyses were performed between SVA and the clinical and radiologic variables. RESULTS: One hundred twenty-two subjects (42 males and 80 females; mean age, 69.93±5.5 years) were included in the study. BMD, femur or spine, was not correlated with SVA or any spinopelvic parameters in both genders (PCC<±0.2), except that spine BMD in men was associated with sacral slope. Univariate regression analysis revealed association between SVA and lumbar lordosis, pelvic tilt, and compression fractures in both genders; it was also associated with age and pelvic incidence in females and with sacral slope in males. Multivariate linear regression model showed lumbar lordosis and compression fracture as variables affecting SVA in both sexes; pelvic incidence was another factor affecting SVA in women only. CONCLUSION: BMD was not associated with sagittal spinal balance in the aged. Sagittal spinal balance was explained partly by lumbar lordosis and compression fracture. Further study is warranted to understand progression of sagittal imbalance with age.

Evaluating the differential electrophysiological effects of the focal vibrator on the tendon and muscle belly in healthy people.

OBJECTIVE: To investigate the electrophysiological effects of focal vibration on the tendon and muscle belly in healthy people. METHODS: The miniaturized focal vibrator consisted of an unbalanced mass rotating offset and wireless controller. The parameters of vibratory stimulation were adjusted on a flat rigid surface as 65 µm at 70 Hz. Two consecutive tests on the different vibration sites were conducted in 10 healthy volunteers (test 1, the Achilles tendon; test 2, the muscle belly on the medial head of the gastrocnemius). The Hoffman (H)-reflex was measured 7 times during each test. The minimal H-reflex latency, maximal amplitude of H-reflex (Hmax), and maximal amplitude of the M-response (Mmax) were acquired. The ratio of Hmax and Mmax (HMR) and the vibratory inhibition index (VII: the ratio of the Hmax after vibration and Hmax before vibration) were calculated. The changes in parameters according to the time and site of stimulation were analyzed using the generalized estimating equation methods. RESULTS: All subjects completed the two tests without serious adverse effects. The minimal H-reflex latency did not show significant changes over time (Wald test: χ(2)=11.62, p=0.07), and between the two sites (χ(2)=0.42, p=0.52). The changes in Hmax (χ(2)=53.74, p<0.01), HMR (χ(2)=20.49, p<0.01), and VII (χ(2)=13.16, p=0.02) were significant over time with the adjustment of sites. These parameters were reduced at all time points compared to the baseline, but the decrements reverted instantly after the cessation of stimulation. When adjusted over time, a 1.99-mV decrease in the Hmax (χ(2)=4.02, p=0.04) and a 9.02% decrease in the VII (χ(2)=4.54, p=0.03) were observed when the muscle belly was vibrated compared to the tendon. CONCLUSION: The differential electrophysiological effects of focal vibration were verified. The muscle belly may be the more effective site for reducing the H-reflex compared to the tendon. This study provides the neurophysiological basis for a selective and safe rehabilitation program for spasticity management with focal vibration.

Feasibility of 18F-FDG PET as a noninvasive diagnostic tool of muscle denervation: a preliminary study.

UNLABELLED: The purpose of this study was to confirm glucose hypermetabolism in denervated muscle and investigate the feasibility of (18)F-FDG PET scanning for the detection of muscle denervation. METHOD: A sciatic neuropathy model in rats was created by nerve resection of the left sciatic nerve and sham operation on the other side. Eight days after denervation, small-animal PET/CT scans of the hindlimbs were acquired. Muscle denervation was confirmed by electrophysiologic and histologic study. RESULTS: All rats showed increased (18)F-FDG uptake in the muscles of the left (denervated) lower legs. The calculated maximum lesion-to-normal counts ratio of the left lower leg anterolateral (left, 11.02 ± 2.08; right, 1.81 ± 0.40, n = 6, P < 0.01) and posterior (left, 9.81 ± 4.58; right, 1.87 ± 0.44, n = 6, P < 0.01) compartment were significantly increased. The electrophysiologic and histologic study verified muscle denervation. CONCLUSION: Glucose hypermetabolism in muscle denervation is an obvious phenomenon. (18)F-FDG PET scanning can be used to visualize muscle denervation.