R. Lee Kirby

Wheelchair-related accidents caused by tips and falls among noninstitutionalized users of manually propelled wheelchairs in Nova Scotia.

ABSTRACTThe purpose of this study was to document what proportion of noninstitutionalized users of manually propelled wheelchairs are affected by wheelchair-related accidents caused by tips and falls, determine the nature and severity of the resulting injuries, and, by comparison with an unaffected group, identify factors associated with the risk of such accidents. We administered a postal questionnaire to as many as possible of the estimated 2055 members of the target population in the province of Nova Scotia. Among the 577 appropriate respondents, 57.4% reported they had completely tipped over or fallen from their wheelchairs at least once, and 66.0% reported having partially tipped. Of the falls and tips that were reported, 46.3% were forward in direction, 29.5% backward and 24.2% sideways. Many of the accidents occurred outdoors or on ramps. A total of 292 injuries were reported by 272 (47.1%) respondents. Most of the injuries (84.3%) were minor (e.g., abrasions, contusions, lacerations and sprains). Of the 15.8% of injuries that were serious, the most common were fractures (10.6%) and concussions (2.7%). Factors that appear to be associated with an increased risk of accidents and injuries included younger age, male gender, paraplegia or spina bifida as the reason for wheelchair use, having had a wheelchair prescribed, some wheelchair features (lightweight, camber, adjustable rear-axle positions, a knapsack), daily use of a wheelchair, propelling the chair with both hands, use of the wheelchair for recreation, use of a sideways transfer (without a transfer board) and doing repairs themselves or having them done by the dealer. Factors associated with a decreased risk include multiple sclerosis, stroke or arthritis as the reason for wheelchair use, attendant propulsion and the use of a one-person assist for transfers. The results of this study, that wheelchair-related accidents caused by tips and falls are very common, that serious injuries are not unusual and that there is a pattern of risk factors, should be useful to wheelchair users, clinicians, manufacturers and regulatory bodies.

The primary erythermalgia-susceptibility gene is located on chromosome 2q31-32.

Primary erythermalgia is a rare disorder characterized by recurrent attacks of red, warm, and painful hands and/or feet. The symptoms are generally refractory to treatment and persist throughout life. Five kindreds with multiple cases of primary erythermalgia were identified, and the largest was subjected to a genomewide search. We detected strong evidence for linkage of the primary erythermalgia locus to markers from chromosome 2q. The highest LOD score (Z) was obtained with D2S2330 (Z(max) = 6.51). Analysis of recombination events identified D2S2370 and D2S1776 as flanking markers, on chromosome 2q31-32. This defines a critical interval of 7.94 cM that harbors the primary erythermalgia gene. Affected members within the additional families also shared a common haplotype on chromosome 2q31-32, supporting our linkage results. Identification of the primary erythermalgia gene will allow a better clinical classification of this pleomorphic group of disorders.

Effect of limited knee-flexion range on peak hip moments of force while transferring from sitting to standing

The hypothesis that limiting the knee-flexion range increases the peak hip-extension moment while transferring from sitting to standing was tested by filming (100 fps) ten normal human volunteers. With the knees flexed 105 degrees from full extension (0 degrees) the mean (+/- 1 S.D.) peak hip-extension moment was 142 (+/- 37) Nm. With the knees flexed only 75 degrees subjects threw their arms and trunks forward to a greater extent, with a peak moment of 253 (+/- 65) Nm (p less than 0.0001). If the peak moments rise to a similar degree in patients with arthritis and limited knee-flexion range, they may accelerate hip joint damage or the loosening of hip endoprostheses.

Reliability of the Performance and Safety Scores of the Wheelchair Skills Test Version 4.1 for Manual Wheelchair Users

OBJECTIVE To evaluate the interrater, intrarater, and test-retest reliability of the total performance and safety scores of the Wheelchair Skills Test version 4.1 (WST 4.1) for manual wheelchairs operated by adult wheelchair users. DESIGN Cohort study. SETTING University research setting. PARTICIPANTS People (N=11) who used manual wheelchairs for community locomotion. INTERVENTIONS Not applicable. MAIN OUTCOME MEASURE Participants were videotaped as they completed the WST 4.1 (30 skills) on 2 separate occasions 1 to 2 weeks apart. Subsequently, raters scored the WST 4.1 from the video recordings and each participant received a total score for performance and safety. Using those scores, interrater, intrarater, and test-retest reliability were determined by using intraclass correlation coefficients (ICCs). Percentages of agreement between raters for individual skills also were calculated. RESULTS Mean ± SD overall WST 4.1 scores for performance and safety were 80.1%±8.5% and 98.0%±2.8%. ICCs for the interrater, intrarater, and test-retest reliability of the performance component were .855, .950, and .901 (P<.001). Safety component ICC scores were .061 (P=.243), .228 (P=.048), and .254 (P=.041). Percentages of agreement between raters for each test item for both the performance and safety scales ranged from 68% to 100%. CONCLUSIONS Reliability of the performance component of the WST 4.1 was excellent, whereas ICCs for the safety component indicated only slight to fair agreement, probably because of the low variability in safety scores. Additional study is needed to further evaluate the reliability of the safety component with a larger and more diverse sample group.

Manual Wheelchair Skills Capacity Predicts Quality of Life and Community Integration in Persons With Spinal Cord Injury

OBJECTIVES To determine wheelchair (WC) skills success rates for manual WC users with spinal cord injury (SCI), to determine subject characteristics associated with the lowest success rates of WC skills, and to characterize the relationship between WC skills and measures of community integration and quality of life (QOL). DESIGN Cross-sectional multisite study. SETTING Six Spinal Cord Injury Model Systems (SCIMS) centers. PARTICIPANTS Individuals with SCI (N=214) who were at least 11 months postinjury, treated at an SCIMS center, and who used a manual WC as their primary means of mobility. INTERVENTION Not applicable. MAIN OUTCOME MEASURES Wheelchair Skills Test (WST) and questionnaires of demographics and characteristics, QOL, and community participation. RESULTS Of the 31 skills in the WST assessed, success rates ranged from 19.6% to 100%. Eight skills had success rates of ≤75%: folding/unfolding the WC (71.5%), ascending (19.6%) and descending (47.2%) a 15-cm curb, ascending (23.2%) and descending (26.5%) stairs, transferring from ground to WC (40.6%), turning 180° in wheelie position (55.2%), and holding a 30-second stationary wheelie (59.9%). Male sex, paraplegia, employed status, lower education, younger age at injury, and white race were among the participant characteristics bivariately associated with higher success rates of several WC skills. After controlling for covariates, higher success rates of several WC skills and a higher total WST score predicted better self-perceived health, higher life satisfaction, and more community participation. CONCLUSIONS For people with SCI who use a manual WC as their primary means of mobility, their ability to perform manual WC skills is associated with higher community participation and life satisfaction. Factors contributing to low success rates need to be investigated, and interventions to improve these rates are needed.

Efficacy and Retention of the French-Canadian Version of the Wheelchair Skills Training Program for Manual Wheelchair Users: A Randomized Controlled Trial

OBJECTIVES To test the hypotheses that, in comparison with a control group that received standard care, users of manual wheelchairs who also received the French-Canadian version of the Wheelchair Skills Training Program (WSTP) would significantly improve their wheelchair-skills capacity and that these improvements would be retained at 3 months. DESIGN Multicenter, single-blind, randomized controlled trial. SETTING Three rehabilitation centers in Montréal, Quebec, Canada. PARTICIPANTS Manual wheelchair users (N=39), a sample of convenience. INTERVENTION Participants were randomly allocated to the WSTP or control groups. Participants in both groups received standard care. Participants in the WSTP group also received a mean of 5.9 training sessions (a mean total duration of 5h and 36min). MAIN OUTCOME MEASURES The French-Canadian version of the Wheelchair Skills Test (WST) (Version 3.2) was administered at evaluation at first time period (baseline) (t1), evaluation at second time period (posttraining) (t2) (a mean of 47d after t1), and at evaluation at third time period (follow-up) (t3) (a mean of 101d after t2). RESULTS At t2, the mean ± SD total percentage WST capacity scores were 77.4%±13.8% for the WSTP group and 69.8%±18.4% for the control group (P=.030). Most of this difference was due to the community-level skills (P=.002). The total and subtotal Wheelchair Skills Test scores at t3 decreased by ≤0.5% from the t2 values, but differences between groups at t3, adjusting for t1, did not reach statistical significance (P≥.017 at a Bonferroni-adjusted α level of .005). CONCLUSION WSTP training improves wheelchair skills immediately after training, particularly at the community-skills level, but this study did not show statistically significant differences between the groups at 3 months.

Spotter strap for the prevention of wheelchair tipping

Injuries caused by wheelchair rear-tipping accidents are common. This article reports on the safety and effectiveness of a spotter strap that attaches to the cross-brace or frame below the center of gravity of an occupied wheelchair. We videotaped five therapists spotting 89 wheelchair users while the users each performed six tasks that were designed to induce rear instability. We induced 16 episodes of complete rear tipping. In all cases, the spotter strap allowed the spotter to stay out of the way during the task, but step in easily when necessary to prevent the wheelchair user from being injured. In one instance, the spotter needed assistance lifting a heavy subject to the upright position after catching the subject with the strap. In summary, the spotter strap is a safe and effective device. We recommend its use when there is a high risk of a rear-tipping accident.

Manual Wheelchair Skills: Objective Testing Versus Subjective Questionnaire

OBJECTIVES To test the hypothesis that the total scores of the Wheelchair Skills Test (WST) version 4.1, an observer-rated scale of wheelchair performance, and the Wheelchair Skills Test Questionnaire (WST-Q) version 4.1, a self-report of wheelchair skills, are highly correlated. We also anticipate that the WST-Q scores will be slightly higher, indicating an overestimation of capacity to perform wheelchair skills as compared with actual capacity. DESIGN A cross-sectional, within-subjects comparison design. SETTING Three Canadian cities. PARTICIPANTS Convenience sample of community-dwelling, experienced manual wheelchair users (N=89) ranging in age from 21 to 94 years. INTERVENTION Not applicable. MAIN OUTCOME MEASURES Participants completed the subjective WST-Q version 4.1 followed by the objective WST version 4.1 in 1 testing session. RESULTS The mean ± SD total percentage scores for WST and WST-Q were 79.5%±14.4% and 83.0%±12.1% for capacity and 99.4%±1.5% and 98.9%±2.5% for safety, respectively. The correlations between the WST and WST-Q scores were ρ=.89 (P=.000) for capacity and ρ=.12 (P=.251) for safety. WST-Q total score mean differences were an average of 3.5%±6.5% higher than WST scores for capacity (P=.000) and .52%±2.8% lower for safety (P=.343). For the 32 individual skills, the percentage agreement between the WST and WST-Q scores ranged from 82% to 100% for capacity and from 90% to 100% for safety. CONCLUSION WST and WST-Q version 4.1 capacity scores are highly correlated although the WST-Q scores are slightly higher. Decisions on which of these assessments to use can safely be based on the circumstances and objectives of the evaluation.

The manual wheelchair wheelie: A review of our current understanding of an important motor skill

Purpose. To review the current understanding of the manual wheelchair wheelie. Method. Review of the literature. Results. A rear wheelchair wheelie occurs when the front wheels, ordinarily in contact with the support surface, are intentionally caused, by means of a transient or sustainable rear pitch, to lift from the surface while the rear wheels remain on the surface. Pitch control (partial or full) is the foundation of many wheelchair skills (e.g., negotiating thresholds, potholes, curbs, steep inclines and gravel). Yet, most wheelchair users never learn to perform this valuable skill. Wheelie capability is affected by the characteristics of the clinician, the wheelchair user, the wheelchair and the environment. Although our understanding of wheelie biomechanics and training methods is evolving, much remains to be learned. Three recent wheelchair developments have wheelie-related implications: a new type of rear anti-tip device (Arc-RAD) that permits wheelie-like function, pushrim-activated power-assisted wheelchairs (PAPAWs) that make wheelie-dependent skills more dangerous and difficult, and a powered wheelchair that has robotic wheelie capabilities (the IBOT). Conclusions. Improvements in our understanding of the nature of wheelies, formalization of training protocols and innovations in wheelchair design hold promise for improved activities and participation by wheelchair users.

Effects of Rear-Wheel Camber on Wheelchair Stability

OBJECTIVES To evaluate how using a wheelchair with rear-wheel camber (when the bottoms of the wheels are farther apart than the tops) is associated with the risk of instability incidents, and to determine the effect of camber on wheelchair stability. DESIGN, SETTING, PATIENTS Epidemiologic data were analyzed from a sample of 576 users of manually propelled wheelchairs in Nova Scotia. A controlled trial was performed using a representative wheelchair occupied by an anthropomorphic test dummy, altering the camber in 5 degrees increments from -15 degrees to +15 degrees. MAIN OUTCOME MEASURES For the epidemiologic study, univariate and multivariate analyses were used. To measure the static stability, a tilting platform was used according to the guidelines of the International Organization for Standardization. RESULTS Camber users reported significantly more instability incidents; of these incidents, more were in the rear direction (40% vs 27%) and fewer in the lateral direction (17% vs 28%) (p < .01). When controlling for other factors, camber was associated with a 3.91-fold increased risk of sustaining an instability incident (p < .001). With increases in camber angle in the laboratory, lateral and forward stability increased and rear stability decreased (with the wheels unlocked and locked) (p < .001). CONCLUSION Camber use is negatively associated with instability incidents in the lateral direction and positively associated with incidents in the backward direction, probably due in part to the effects of camber on lateral and rear stability.