Megan K. MacGillivray

Long‐term functional and mobility outcomes for individuals with arthrogryposis multiplex congenita

Arthrogryposis multiplex congenita (AMC) is a birth defect that involves congenital joint contractures in two or more joints including the limbs, spine, and jaw. The purpose of our study was to identify long‐term outcomes of adults with AMC. We recruited 177 participants from over 15 countries, making this the largest international study of adults with AMC. Participants provided demographic information including living situation and mobility and completed two standardized outcome measures, of quality of life and physical activity, using an online survey format. The data were compiled and descriptive analyses were performed. The study group consisted of 72% females and a mean age of 39 years. Over 90% of participants had upper and lower limb involvement, 35% had scoliosis or lordosis while 16% had jaw problems. Participants had an average of nine (0–70) surgeries at the time of the study. The majority (75%) of respondents lived independently of family members (on their own or with a partner). Participants were nearly three times more likely to have a graduate degree than the general US population. Participants reported lower physical function scores than the general US population; however, they reported similar or higher scores for the other quality of life domains of the SF‐36. They were considerably less physically active than able‐bodied individuals. Half of participants experienced chronic back pain and 60% reported joint pain. Additionally, almost half of the participants took regular pain medications.

Mechanical efficiency of two commercial lever-propulsion mechanisms for manual wheelchair locomotion.

The purpose of this study was to (1) evaluate the mechanical efficiency (ME) of two commercially available lever-propulsion mechanisms for wheelchairs and (2) compare the ME of lever propulsion with hand rim propulsion within the same wheelchair. Of the two mechanisms, one contained a torsion spring while the other used a roller clutch design. We hypothesized that the torsion spring mechanism would increase the ME of propulsion due to a passive recovery stroke enabled by the mechanism. Ten nondisabled male participants with no prior manual wheeling experience performed submaximal exercise tests using both lever-propulsion mechanisms and hand rim propulsion on two different wheelchairs. Cardiopulmonary parameters including oxygen uptake (VO2), heart rate (HR), and energy expenditure (En) were determined. Total external power (Pext) was measured using a drag test protocol. ME was determined by the ratio of Pext to En. Results indicated no significant effect of lever-propulsion mechanism for all physiological measures tested. This suggests that the torsion spring did not result in a physiological benefit compared with the roller clutch mechanism. However, both lever-propulsion mechanisms showed decreased VO2 and HR and increased ME (as a function of slope) compared with hand rim propulsion (p < 0.001). This indicates that both lever-propulsion mechanisms tested are more mechanically efficient than conventional hand rim propulsion, especially when slopes are encountered.

Test-Retest Reliability and Minimal Detectable Change of the SmartWheel Clinical Protocol

OBJECTIVES (1) To quantify the intra- and intersession reliability and minimal detectable change (MDC) of the SmartWheel clinical protocol (SCP) and (2) to compare the reliability of the SCP between experienced and naïve wheelchair users. DESIGN Test-retest study. SETTING Biomechanics laboratory. PARTICIPANTS Manual wheelchair users (WCUs) (n=10) with 1 to 32 years of wheeling experience and able-bodied (AB) naïve users (n=15). INTERVENTIONS Not applicable. MAIN OUTCOME MEASURES Wheelchair propulsion parameters including average peak force, push frequency, push length, and velocity were measured according to the SCP but with 5 trials per session, for 2 sessions. WCUs and AB users were analyzed separately. Intraclass correlation coefficients ([ICC](2,1) and ICC(2,5)) were calculated to assess intrasession reliability. ICC(2,1) and MDC (with 95% confidence) were calculated for each SCP parameter using a single trial from each session and with the mean of 5 repeated measures to evaluate intersession reliability. RESULTS Intra- and intersession reliability for WCU parameters ranged from high to very high correlation (ICC range, .70-.99). For AB parameters, intrasession ICC(2,1) ranged from moderate to very high (ICC range, .50-.92), while intersession ICC(2,1) indicated low to very high correlation (ICC range, .25-.90). Estimates of standard error of measurement and MDC were provided for each parameter. For both WCUs and AB users, using the means from 5 trials increased intra- and intersession ICC and decreased MDC values. All MDC values were lower for WCUs compared with AB users. CONCLUSIONS The SCP is a reliable method for assessing propulsion parameters in WCUs, even if just 1 trial is taken per session. AB users showed lower intra- and intersession reliability compared with WCUs. Therefore, for AB users or individuals with minimal wheeling experience, averaging multiple trials is recommended for the SCP.

Goal satisfaction improves with individualized powered wheelchair skills training

Abstract Purpose: To determine improvements in goal satisfaction following individualized mobility-related powered wheelchair skills training and whether changes in satisfaction are maintained 3 months post-training. Materials and methods: Seventeen powered wheelchair users, from two centres, who were randomized to the training intervention from a larger multicentre study, were included in this secondary analysis. The intervention consisted of five 30-min individualized Wheelchair Skills Training Program sessions. Participants rated their current satisfaction with each of their goals from 0 to 10 (10 being the highest) prior to training, immediately after the intervention, and approximately 3 months following the intervention. Themes relating to the participants’ goals were also explored. Results: Goal satisfaction scores improved statistically (p < .001) from baseline (4.7 ± 1.9) to immediately following training (8.0 ± 1.0) and were maintained 3 months (8.3 ± 1.2) following the intervention. Participants’ goal satisfaction scores were not significantly correlated with goal attainment scores recorded by the trainer (r = 0.387, n = 17, p = .125). The majority of goals set fell into the broader “manoeuvring” category. Conclusion: Goal satisfaction following the Wheelchair Skills Training Program improved years after initially learning how to operate a powered wheelchair. The five training sessions were effective in improving goal satisfaction. The quantification of goal satisfaction appears to be a sensitive outcome for powered wheelchair users undergoing mobility-related training. Implications for rehabilitation Goal satisfaction improved following the Wheelchair Skills Training Program. Even with years of powered wheelchair experience, the majority of goals set fell into the broader “manoeuvring” category. An individual’s goal satisfaction may not correlate with whether they have attained their goal as determined by a trainer.

Improving Self-Management Skills Among People with Spinal Cord Injury: Protocol for a Mixed-Method Study (Preprint)

Background Most people with spinal cord injury will develop secondary complications with potentially devastating consequences. Self-management is a key prevention strategy for averting the development of secondary complications and their recurrence. Several studies have shown that self-management programs improve self-management behaviors and health outcomes in individuals living with chronic conditions such as asthma, diabetes, hypertension, and arthritis. Given the burgeoning health care costs related to secondary complications, we developed an alternative electronic health–based implementation to facilitate the development of self-management skills among people with spinal cord injury. Objective This study aims to evaluate the efficacy of a self-management app in spinal cord injury populations. The primary outcome is attainment of self-selected, self-management goals. Secondary outcomes include increases in general and self-management self-efficacy and reductions in self-reported health events, health care utilization, and secondary complications related to spinal cord injury. This study also aims to explore how the intervention was implemented and how the app was experienced by end users. Methods This study will employ a mix of qualitative and quantitative methods. The quantitative portion of our study will involve a rater-blinded, randomized controlled trial with a stepped wedge design (ie, delayed intervention control group). The primary outcome is successful goal attainment, and secondary outcomes include increases in self-efficacy and reductions in self-reported health events, health care utilization, and secondary conditions related to spinal cord injury. The qualitative portion will consist of semistructured interviews with a subsample of the participants. Results We expect that the mobile self-management app will help people with spinal cord injury to attain their self-management goals, improve their self-efficacy, reduce secondary complications, and decrease health care utilization. Conclusions If the results are positive, this study will produce credible new knowledge describing multiple outcomes that people with spinal cord injury realize from an app-based self-management intervention and support its implementation in clinical practice. Trial Registration ClinicalTrials.gov NCT03140501; http://clinicaltrials.gov/ct2/show/NCT03140501 (Archived by WebCite at http://www.webcitation.org/73Gw0ZlWZ) International Registered Report Identifier (IRRID) PRR1-10.2196/11069

Exploring the ecological validity and variability of a 10-min bout of wheeling

Abstract Purpose: To determine the ecological validity of using able-bodied participants to perform a 10-min wheeling trial by (1) evaluating changes in biomechanics over the trial in manual wheelchair users and able-bodied participants naïve to wheeling and (2) describing differences in changes and variability between groups. Materials and methods: Manual wheelchair users (n = 7, 2–27 years’ experience) and able-bodied participants (n = 11) wheeled for 10 min. Kinetic and temporal variables were collected and averaged over each minute, while wheeling strategy (movement pattern) was categorized at minutes 1 and 10. Results: There was a main effect of time for push angle, and a main effect of group for average push angle, tangential force and total force. Manual wheelchair users used larger push angles and forces compared to able-bodied participants. Surprisingly, intercycle variability did not differ between groups. Conclusion: Using able-bodied participants to represent manual wheelchair users performing a 10-min wheeling trial is not ecologically valid and caution should be used when interpreting push angle and forces applied to the pushrim. Considering that push angle was the only variable that demonstrated a main effect of time, long durations (e.g., 10 min) of wheeling may be appropriate for use in study designs acknowledging potential changes in wheeling strategy and push angle. Implications for Rehabilitation Some experienced wheelchair users and non-wheelchair users modify their movement pattern from an arc to a circular pattern within a 10-min wheeling trial. There are clear biomechanical differences in push angle and forces applied to the pushrim between wheelchair users with experience and able-bodied non-wheelchair users. Able-bodied participants who have no prior manual wheeling experience are no more variable than long-term wheelchair users. Variability may play an important role in wheelchair propulsion.

The influence of a polymer damper on swing-through crutch gait biomechanics

Forearm crutch technology has evolved slowly compared to other assistive mobility devices, despite the highly repetitive nature of forearm crutch gait and the high incidence of overuse injuries. Using 13 able-bodied volunteers between the ages of 19 and 27, we compared the ground reaction forces of a novel crutch design featuring an elastomeric polymer situated below the handle to an identical design without a damper system and to a commercially available generic rigid forearm crutch model. There were no differences in peak vertical force or impulse between crutches. The crutch with the damper system demonstrated a significantly smaller peak braking force and impulse compared to the generic forearm crutch model. However, the crutch with the damper system demonstrated a significantly larger peak propulsive force and impulse compared to both crutch models. This finding indicates that a forearm crutch with a damper system may help to propel the crutch forward when walking on level surfaces, which could impact forward momentum.

Prior experience does not alter modulation of cutaneous reflexes during manual wheeling and symmetrical arm cycling

Previous research has reported that training and experience influence H-reflex amplitude during rhythmic activity; however, little research has yet examined the influence of training on cutaneous reflexes. Manual wheelchair users (MWUs) depend on their arms for locomotion. We postulated that the daily dependence and high amount of use of the arms for mobility in MWUs would show differences in cutaneous reflex modulation during upper limb cyclic movements compared with able-bodied control subjects. We hypothesized that MWUs would demonstrate increased reflex response amplitudes for both manual wheeling and symmetrical arm cycling tasks. The superficial radial nerve was stimulated randomly at different points of the movement cycle of manual wheeling and symmetrical arm cycling in MWUs and able-bodied subjects naive to wheeling. Our results showed that there were no differences in amplitude modulation of early- or middle-latency cutaneous reflexes between the able-bodied group and the MWU group. However, there were several differences in amplitude modulation of cutaneous reflexes between tasks (manual wheeling and symmetrical arm cycling). Specifically, differences were observed in early-latency responses in the anterior and posterior deltoid muscles and biceps and triceps brachii as well as in middle-latency responses in the anterior and posterior deltoid. These data suggest that manual wheeling experience does not modify the pattern of cutaneous reflex amplitude modulation during manual wheeling. The differences in amplitude modulation of cutaneous reflexes between tasks may be a result of mechanical differences (i.e., hand contact) between tasks.