A survey of protective cushion usage in individuals with spinal cord injury while traveling in a motor vehicle and on a commercial airliner

Objective

While there are specific recommendations for pressure relieving cushions when seated in a wheelchair, there is a paucity of information regarding prescribed wheelchair cushions for persons with spinal cord injury (SCI) when traveling and not in their wheelchair seat. A questionnaire was designed to ascertain if individuals with SCI who are primarily wheelchair users utilize a prescribed wheelchair cushion when traveling in a motor vehicle (MV) or on a commercial airliner, as not utilizing one may be a causative factor in developing pressure ulcers.

Design and setting

Survey design in an outpatient SCI rehabilitation setting.

Participants

Full-time wheelchair users, with chronic (>1 year) SCI.

Results

Forty-two participants completed the survey, with a mean age of 39 years old and time post-injury of 10.4 years. All subjects used a prescribed wheelchair cushion when seated in their wheelchair. Twenty-seven subjects reported transferring to a MV seat (59.5% of sample), with 25 (92.6%) reporting not using a prescribed wheelchair cushion when sitting directly on the MV seat. For subjects who traveled on an airplane (n = 23–54.8%), 19 (82.6%) reported that they do not sit on a prescribed specialty cushion.

Conclusion

Persons with chronic SCI, who are primary wheelchair users, utilize prescribed wheelchair cushions when sitting in their wheelchair, but most do not utilize a prescribed wheelchair cushion when seated in a MV (if they transfer out of their chair) or on a airplane seat. Studies to determine the pressures over the bony prominences on their travel surfaces may need to be undertaken to see whether the pressures are appropriate, as they may be a source of skin breakdown.     

Load Redistribution in Variable Position Wheelchairs in People With Spinal Cord Injury

Abstract

Background/Objective: Tilt and recline variable position seating systems are most commonly used for pressure relief to decrease potential for skin breakdown. This study provides quantitative information on the magnitudes of loading on the seat and back during phases of tilt, recline, and standing. The objective of this study was to show that the amount of force reduction at the seat would differ across these 3 methods within their respective clinical ranges.

Participants: Six able-bodied (AB) subjects (2 men, 4 women) with a median age of 25 years, and 10 subjects (8 men, 2 women) with spinal cord injury (SCI) with a median age of 35.5 years.

Methods: Subjects sat on a power wheelchair with Tekscan pressure mats placed underneath a foam backrest and cushion. Data were collected at 5 positions for each method. Order of position and method tested were randomized. Linear regressions were used to calculate the relationships of normalized seat and backrest forces to seat and backrest angles for each chair configuration.

Results: Normalized seat loads had strong linear relationships with the angles of change in tilt, recline, and standing for both groups. Maximum decreases in seat load occurred at full standing and full recline in the SCI subjects and in full standing in the AB subjects. Loads linearly increased on the back during tilt and recline and linearly decreased during standing for both groups.

Conclusions: Standing and recline offered similar seat load reductions at their respective terminal positions. Standing also reduced loading on the backrest. Recognizing that each method had clinical benefits and drawbacks, the results of this study indicate that tilt, recline, and standing systems should be considered as a means of weight shifting for wheelchair users.     

Burn on the buttocks caused by gel wheelchair cushion left on driver’s seat of hand control car

Context: Nowadays, people with paraplegia and quadriplegia have greater opportunities to venture into the general public. However, there is also an increased risk of associated hazards.

Findings: This report describes a 42-year-old man with paraplegia, who was insensate below the T7 level and sustained burns from sitting on a gel wheelchair cushion that had been left on the driver-side seat of a hand control car on a sunny day. Physical examination revealed deep partial-thickness burns on both his buttocks. He underwent surgical debridement and received an autologous split-thickness skin graft, and healed well.

Conclusion In modern times, the lives of people with paralysis are no longer restricted to the bed and wheelchair. Active people with spinal cord injuries inevitably diversify the use of wheelchair cushions in many ways; therefore, there is a greater possibility for the occurrence of associated hazards. This is a preventable issue, so both the user and manufacturers should recognize this potential hazard of gel wheelchair cushions.     

Relationships Among Cushion Type,Backrest Height,Seated Posture,And Reach Of Wheelchair Users With Spinal Cord Injury

Abstract

Background: Seated posture and trunk control are important factors affecting upper extremity (UE) function of wheelchair users. A stable pelvis and trunk are required to provide a base from which UE movement occurs, but, conversely, the ability to move one’s trunk and pelvis can increase functional ranges of motion. For wheelchair users, balancing sufficient trunk support with adequate trunk mobility has important functional and medical consequences.

Objective: To determine the effect of cushion and backrest height on posture and reach and to determine the relationship between posture and UE reach using a randomized 2 X 3 repeated-measures factorial design.

Methods: Twenty-two subjects with spinal cord injury were tested in 6 configurations, including 3 types of cushions (segmented air, contoured viscous fluid/foam, and air/foam) and 2 of 3 backrest heights (referenced to Tl 2, inferior scapular angle, and scapular spine) while performing unilateral and bilateral reaching tasks. Seated posture (pelvic tilt and torso angle) and American Spinal Injury Association (ASIA) score were also measured.

Results: Pelvic tilt and ASIA score were significant predictors of reach. No evidence was found indicating cushion type or backrest height affected reach or posture. No consistent patterns of posture were found across cushion types or backrest heights.

Conclusions: The posture adopted by wheelchair users is a more important influence on UE reach than are the cushion or backrest height used. Sitting with increased posterior pelvic tilt enhanced stability and permitted greater reach. Because individuals adopt different postures when using different cushions and backrest heights, clinicians should monitor posture while assessing seating and function of wheelchair users.     

Relationship between ultrasonographically low-echoic lesions under the skin,wheelchair sitting time,and interface pressure on ischial region in individuals with chronic spinal cord injury

Objective: To determine the relationship between physical findings, wheelchair sitting time, and interface pressure on ischial region in subjects with spinal cord injury (SCI).Design: Cross-sectional study.Setting: Rehabilitation center in Japan.Participants: Manual wheelchair users with chronic SCI (n = 45).Interventions: Pressure ulcers (PU) were diagnosed by inspection, palpation, and ultrasonography. Self-reports were obtained on wheelchair sitting time and pressure mapping was recorded while the subject was seated on the wheelchair.Outcome measures: Subjects were divided into those with ultrasonographically low-echoic lesions (PU-positive group, n = 11) and no such lesions (PU-negative group, n = 34). Outcome measures included wheelchair sitting time and interface pressure at bilateral ischial regions.Results: Using ultrasonography, 13 low-echoic lesions were identified in 11 subjects of the PU-positive group. The pressure duration was longer and interface pressure was significantly higher in subjects of the PU-positive group compared with those of the PU-negative group (P < 0.05 and P < 0.001, respectively).Conclusions: This is the first study to evaluate the interrelationship between physical findings, sitting time, and ultrasonographically measured interface pressure on ischial region area in subjects with spinal cord injury. To prevent pressure ulcers, we recommend avoidance of prolonged wheelchair sitting and measures that can reduce the interface pressure. These variables should be carefully tailored to the needs of the individual subjects with SCI.     

Measuring Tissue Perfusion During Pressure Relief Maneuvers: Insights Into Preventing Pressure Ulcers

Abstract

Background/Objective: To study the effect on tissue perfusion of relieving interface pressure using standard wheelchair pushups compared with a mechanical automated dynamic pressure relief system.

Design: Repeated measures in 2 protocols on 3 groups of subjects.

Participants: Twenty individuals with motor-complete paraplegia below T4, 20 with motor-complete tetraplegia, and 20 able-bodied subjects.

Methods: Two 1-hour sitting protocols: dynamic protocol, sitting configuration alternated every 10 minutes between a normal sitting configuration and an off-loading configuration; wheelchair pushup protocol, normal sitting configuration with standard wheelchair pushup once every 20 minutes.

Main Outcome Measures: Transcutaneous partial pressures of oxygen and carbon dioxide measured from buttock overlying the ischial tuberosity and interface pressure measured at the seat back and buttocks. Perfusion deterioration and recovery times were calculated during changes in interface pressures.

Results: In the off-loading configuration, concentrated interface pressure during the normal sitting configuration was significantly diminished, and tissue perfusion was significantly improved. Wheelchair pushups showed complete relief of interface pressure but incomplete recovery of tissue perfusion.

Conclusions: Interface pressure analysis does not provide complete information about the effectiveness of pressure relief maneuvers. Measures of tissue perfusion may help establish more effective strategies. Relief achieved by standard wheelchair pushups may not be sufficient to recover tissue perfusion compromised during sitting; alternate maneuvers may be necessary. The dynamic seating system provided effective pressure relief with sustained reduction in interface pressure adequate for complete recovery of tissue perfusion. Differences in perfusion recovery times between subjects with spinal cord injury (SCI) and controls raise questions about the importance of changes in vascular responses to pressure after SCI.     

Deep tissue loads in the seated buttocks on an off‐loading wheelchair cushion versus air‐cell‐based and foam cushions: finite element studies

For wheelchair users, a common injury is a sitting‐acquired pressure ulcer (PU) which typically onsets near the interface between the ischial tuberosity (IT) and the overlying soft tissues. The risk of developing PUs can be reduced considerably if an adequate cushion is placed on the wheelchair in order to protect tissues from PUs by minimising interface mechanical loads between the body and cushion and also, exposure to internal soft tissue loads. In this work, we studied the biomechanical performances of an off‐loading (OL) cushion with limited adjustability, in comparison to a standard foam cushion and a fully adjustable air‐cell‐based (ACB) cushion. These different cushion design approaches were methodologically and quantitatively analysed and compared here using a finite element (FE) modelling framework. We determined the internal mechanical deformations, strains and stresses in soft tissues of the seated buttocks during symmetric sitting, in a specific anatomy of a person with a spinal cord injury that was acquired during sitting in an open, magnetic resonance imaging configuration. Our results have shown that strains and stresses in muscle, fat and skin tissues are orders of magnitude lower for the ACB cushion with respect to the standard foam and OL cushions. The OL cushion design has taken the approach of protecting at‐risk sites of the buttocks by transferring local internal tissue loads away from the ITs and towards the greater trochanters, at the price of increasing exposure to internal tissue loads at sites other than the ITs. The ACB cushion design, however, has taken a different approach, that is, immersion and envelopment of the entire buttocks structure, which is useful for minimising the exposure to internal tissue loads throughout the whole buttocks. Quantifying performances of wheelchair cushions using FE modelling provides insights into deep tissue loads, which is essential for informed decision‐making in developing sitting solutions for individuals at risk, as well as for patient groups.     

Clinical evaluation of seating in persons with complete thoracic spinal cord injury

STUDY DESIGN: Consecutive male patients studied with photographic measurement of a combination of clinical methods. OBJECTIVES: To describe seating in individuals with complete thoracic spinal cord injury (SCI) by using a combination of clinical methods. SETTING: Spinalis SCI unit, Stockholm, Sweden. METHODS: Wheelchair specifications were documented. Measurements of posture from photographs in 30 male subjects with complete thoracic SCI, sitting in a relaxed and an upright position on a standardized surface and in a wheelchair were calculated. A comparison was made between positions and seating surfaces. An examiner's classification of lower trunk position in wheelchair was compared to subjects' evaluations. SCI subjects reported sitting support, satisfaction, and wishes for improvement. RESULTS: Most SCI subjects used similar wheelchair specifications. None of the backrests were custom designed. Relatively small differences were found between the relaxed and upright position in the wheelchair regarding measurements of posture and according to the examiner's classification of the lower trunk position. Only 13/30 SCI subjects were sitting with the lower trunk centered relative to the backrest in the upright position. The examiner's classification and the subjects' evaluation of asymmetric sitting were not always in agreement. Only 12/30 SCI subjects were satisfied with their way of sitting. CONCLUSION: Current wheelchair specifications and adjustments seem to inhibit a postural correction towards upright sitting and fail to provide sufficient lateral support. Findings indicate an inability for SCI subjects to vary their sitting position in a wheelchair to a large extent. Both an examiner's classification and subjects' evaluation of asymmetric sitting are necessary to obtain a sufficient knowledge base for subsequent adjustment. By using methods regarding different aspects of seating, a more comprehensive view of seating was achieved. The combination of clinical methods seems to be useful in order to describe seating in individuals with complete thoracic SCI.     

Measuring seating pressure,area, and asymmetry in persons with spinal cord injury

The goal of this study was to measure characteristics of seat loading in manual wheelchair users with complete spinal cord injury (SCI). Pressure distribution on the seating area of 25 adult males with SCI and eight non-injured adult males was measured in a relaxed and an upright posture on a standardized hard surface. Subjects with SCI were also tested in their wheelchairs. Maximum pressure, contact area, area of the highest pressure, and three asymmetry indices were compared. Subjects with SCI have higher pressure distributed over a smaller area, have a much smaller contact area, and distribute the loading more asymmetrically than non-injured subjects. Upright posture only corrects for some loading problems, while the wheelchair corrects for more loading parameters. Routine clinical seat loading evaluation may lead to improved chair and cushion selection for patients with SCI and may even alert clinicians to patients at high risk for complications due to high or unbalanced loads.     

Relationships among cushion type, backrest height, seated posture, and reach of wheelchair users with spinal cord injury

BACKGROUND: Seated posture and trunk control are important factors affecting upper extremity (UE) function of wheelchair users. A stable pelvis and trunk are required to provide a base from which UE movement occurs, but, conversely, the ability to move one's trunk and pelvis can increase functional ranges of motion. For wheelchair users, balancing sufficient trunk support with adequate trunk mobility has important functional and medical consequences. OBJECTIVE: To determine the effect of cushion and backrest height on posture and reach and to determine the relationship between posture and UE reach using a randomized 2 x 3 repeated-measures factorial design. METHODS: Twenty-two subjects with spinal cord injury were tested in 6 configurations, including 3 types of cushions (segmented air, contoured viscous fluid/foam, and air/foam) and 2 of 3 backrest heights (referenced to T12, inferior scapular angle, and scapular spine) while performing unilateral and bilateral reaching tasks. Seated posture (pelvic tilt and torso angle) and American Spinal Injury Association (ASIA) score were also measured. RESULTS: Pelvic tilt and ASIA score were significant predictors of reach. No evidence was found indicating cushion type or backrest height affected reach or posture. No consistent patterns of posture were found across cushion types or backrest heights. CONCLUSIONS: The posture adopted by wheelchair users is a more important influence on UE reach than are the cushion or backrest height used. Sitting with increased posterior pelvic tilt enhanced stability and permitted greater reach. Because individuals adopt different postures when using different cushions and backrest heights, clinicians should monitor posture while assessing seating and function of wheelchair users.     

Measuring tissue perfusion during pressure relief maneuvers: insights into preventing pressure ulcers

BACKGROUND/OBJECTIVE: To study the effect on tissue perfusion of relieving interface pressure using standard wheelchair pushups compared with a mechanical automated dynamic pressure relief system. DESIGN: Repeated measures in 2 protocols on 3 groups of subjects. PARTICIPANTS: Twenty individuals with motor-complete paraplegia below T4, 20 with motor-complete tetraplegia, and 20 able-bodied subjects. METHODS: Two 1-hour sitting protocols: dynamic protocol, sitting configuration alternated every 10 minutes between a normal sitting configuration and an off-loading configuration; wheelchair pushup protocol, normal sitting configuration with standard wheelchair pushup once every 20 minutes. MAIN OUTCOME MEASURES: Transcutaneous partial pressures of oxygen and carbon dioxide measured from buttock overlying the ischial tuberosity and interface pressure measured at the seat back and buttocks. Perfusion deterioration and recovery times were calculated during changes in interface pressures. RESULTS: In the off-loading configuration, concentrated interface pressure during the normal sitting configuration was significantly diminished, and tissue perfusion was significantly improved. Wheelchair pushups showed complete relief of interface pressure but incomplete recovery of tissue perfusion. CONCLUSIONS: Interface pressure analysis does not provide complete information about the effectiveness of pressure relief maneuvers. Measures of tissue perfusion may help establish more effective strategies. Relief achieved by standard wheelchair pushups may not be sufficient to recover tissue perfusion compromised during sitting; alternate maneuvers may be necessary. The dynamic seating system provided effective pressure relief with sustained reduction in interface pressure adequate for complete recovery of tissue perfusion. Differences in perfusion recovery times between subjects with spinal cord injury (SCI) and controls raise questions about the importance of changes in vascular responses to pressure after SCI.     

Delayed diagnosis of an unsuspected pelvic fracture in a patient with tetraplegia

Abstract

Study design

Case report.

Context

In patients with a complete spinal cord injury (SCI) above T6 level, autonomic dysreflexia (AD) can be the only alerting sign of complications below the level of injury. A case report is presented of a patient with tetraplegia who progressively developed an AD syndrome after falling from a wheelchair. Initially, he was treated for symptomatic urinary tract infection and only later an unstable pelvic fracture was detected.

Findings

A patient with chronic tetraplegia fell from his wheelchair while intoxicated. After the fall, he showed no signs of injury. Two days later, AD symptoms appeared while lying on his side or sitting. He presented to his community-based physician and received antibiotics for concomitant urinary tract infection. Because of persisting complaints, the patient was referred to the Spinal Cord Unit. Once the history of falling from the wheelchair was made known, symptoms of AD were suggestive of an internal injury. Radiography showed pelvic fracture and conservative treatment was administered. The fractures healed in 3 months, the therapeutic bed rest regimen was relaxed without trigerring AD symptoms.

Conclusion

AD symptoms can suggest complications below the SCI level. Awareness and recognition of these symptoms are of utmost importance. However, etiology may be misleading. The role of a community-based general physician is to recognize the right moment when the need of a specialized assessment in a Spinal Cord Unit arises. In addition, patients should also be well informed about the most common possible complications from specialized SCI centers.     

Evaluation Of Selected Sidewalk Pavement Surfaces For Vibration Experienced By Users Of Manual AndPowered Wheelchairs

Abstract

Background: Obstades such as bumps, curb descents, and uneven driving surfaces cause vibrations that affect the wheelchair, and in turn, the wheelchair user. Chronic exposure can cause low-back pain, disk degeneration, and other harmful effects. Little research has been conducted to assess the vibrations experienced by wheelchair users.

Objective: The purpose of this study was to conduct an evaluation of the vibration exposure du ring electric-powered wheelchair driving and mechanical energy requirements for manual wheelchair propulsion over selected sidewalk surfaces. The goal was to determine the criteria for a wheelchair-pedestrian access route that does not require excessive propulsive work or expose wheelchair users to potentially harmful vibrations.

Methods: Ten unimpaired individuals participated in this study. Six sidewalk surfaces were tested. Measured variables included power of the acceleration per octave, mechanical work to propel over surfaces, peak acceleration, and frequency at which peak acceleration occurs.

Results: For both the manual and electric-powered wheelchair, at 1 m/s, significant differences were found in peak accelerations between the seat and footrest (P < 0.0001) and between the sidewalk surfaces (P = 0.004 ). The greatest risk for injury caused by shock and vibration exposure occurs at frequ encies near the natural frequency of seated humans (4-15 Hz). The values for work required to propel over the surfaces tested were not stat istically significantly different. Besides appearance and construction, the only distinguishing characteristic was surface roughness caused by the joints.

Conclusion: When treating the poured concrete sidewalk as the standard, surfaces 2, 3, 5, and 6 compared most favorably in t erms of vibration exposure, whereas surface 4 produced mixed results. Surfaces 2, 3, 5, and 6 yielded results that were similar to the poured concrete sidewalk and could be considered acceptable for wheelchair users. in conclusion, surfaces other than the t raditional poured concrete can be used for pedestrian access routes without adding vibration exposure or reducing propulsion efficiency.     

Non Traumatic Dislocation of Shoulder with Rupture of Axillary Vessel Branch in a Paraplegic Patient: A Case Report

ABSTRACT

Spinal cord injured (SCI) patients utilize the shoulder joints for wheelchair propulsion, for transfers in and out of wheelchairs and for wheelchair “push-ups” for pressure relief, to prevent pressure sores. Accurate incidence of shoulder dislocation in SCI patients is not known. A majority of the dislocations seen are secondary to trauma. A 66-year-old, T10 paraplegic since 1942, developed severe osteoarthritic changes in both shoulders and experienced nontraumatic, recurrent dislocation of his right shoulder with a rupture of the axillary vessel branch. This case is reported here because of its rarity. (J Am Paraplegia Soc 1990; 13: 15–17)     

Trunk strength and function using the multidirectional reach distance in individuals with non-traumatic spinal cord injury

Context

Trunk control is essential to engage in activities of daily living. Measuring trunk strength and function in persons with spinal cord injury (SCI) is difficult. Trunk function has not been studied in non-traumatic SCI (NTSCI).

Objectives

To characterize changes in trunk strength and seated functional reach in individuals with NTSCI during inpatient rehabilitation. To determine if trunk strength and seated reach differ between walkers and wheelchair users. To explore relationships between trunk and hip strength and seated functional reach.

Design

Observational study.

Setting

Two SCI rehabilitation facilities.

Participants

32 subacute inpatients (mean age 48.0 ± 15.4 years).

Outcome measures

Isometric strength of trunk and hip and function (Multidirectional Reach Test: MDRT) were assessed at admission and within 2 weeks of discharge. Analysis of variance was conducted for admission measures (MDRT, hip and trunk strength) between walkers and wheelchair users. Changes in MDRT, hip and trunk strength were evaluated using parametric and non-parametric statistics. The level of association between changes in values of MRDT and strength was also examined.

Results

Significant differences between walkers and wheelchair users were found for strength measures (P < 0.05) but not for MDRT. Left- and right-sided reaches increased in wheelchair users only (P < 0.05). Associations between changes in hip strength, trunk strength, and reach distance were found (R = 0.67–0.73).

Conclusion

In clinical settings, it is feasible and relevant to assess trunk, hip strength, and MRDT. Future studies require strategies to increase the number of participants assessed, in order to inform clinicians about relevant rehabilitation interventions.     

Associations of Mode of Locomotion and Independence in Locomotion With Long-Term Outcomes After Spinal Cord Injury

Background/Objective: To explore the association of mode of locomotion (ambulation vs wheelchair use) and independence in locomotion (independent vs require assistance) with health, participation, and subjective well-being (SWB) after spinal cord injury (SCI).

Research Design: Secondary analysis was conducted on survey data collected from 2 rehabilitation hospitals in the Midwest and a specialty hospital in the southeastern United States. The 1,493 participants were a minimum of 18 years of age and had traumatic SCI of at least 1 year duration at enrollment.

Main Outcome Measures: Three sets of outcome measures were used: SWB, participation, and health. SWB was measured by 8 scales and a measure of depressive symptoms, participation by 3 items, health by general health ratings, days in poor health, hospitalizations, and treatments.

Results: Small but significant associations were observed between independence in locomotion and every outcome. Ambulation was associated with greater participation but a mixed pattern of favorable and unfavorable health and SWB outcomes. Supplemental analyses were conducted on those who ambulated but who were dependent on others to do so (n = 117), because this group reported poor outcomes in several areas. Individuals who were independent in wheelchair use reported substantially better outcomes than nonwheelchair users and those dependent on others in wheelchair use.

Conclusions: Although ambulation is often a recovery goal, individuals with SCI who ambulate do not uniformly report better outcomes than wheelchair users, and those who depend on others for assistance with ambulation may experience a unique set of problems.     

Development of a comprehensive mobile assessment of pressure (CMAP) system for pressure injury prevention for veterans with spinal cord injury

Objective: This paper reports the iterative redesign, feasibility and usability of the Comprehensive Mobile Assessment of Pressure (CMAP) system’s mobile app used by Veterans with SCI.

Design: This three-year, multi-staged study used a mixed-methods approach.

Setting: Minneapolis VA Health Care System, Minneapolis, Minnesota.

Participants: Veterans with spinal cord injury (N?=?18).

Interventions: Veterans with spinal cord injury engaged in iterative focus groups and personal interviews, sharing their needs and desires for the CMAP app redesign. App developers used these data for the redesign. The redesigned CMAP app was tested for six-weeks in users’ homes.

Outcome Measures: Quantitative (surveys) and qualitative (interviews) methods measured feasibility for self-management of seating pressure. Qualitative data were audio recorded, transcribed, anonymized, and coded. Survey data were analyzed using summary statistics.

Results: After the CMAP system’s redesign, the in-home use interview found: (1) any tool that can assist in prevention and monitoring of skin ulcers is important; (2) the desired key features are present in the app; (3) the main barrier to CMAP use was inconsistent functionality; (4) when functioning as expected, the live pressure map was the central feature, with reminders to weight shift also of high importance. The survey found: power wheelchair users tended to score closer than manual wheelchair users to the positive response end ranges on two separate surveys.

Conclusions: Overall both the power and manual wheelchair users reported that they wanted to use the system, felt confident using the system, and that the functions of the system were well integrated.     

Power seat function usage and wheelchair discomfort for power wheelchair users

Objectives: To investigate correlations between power seat functions (PSFs) usage and wheelchair discomfort.

Design: Quasi-experimental design: Time series design.

Setting: In-home trial in participants’ home/community.

Participants: Thirteen power wheelchair users who independently used power wheelchairs equipped with PSFs as their primary means of mobility.

Main Outcome Measures: PSF usage variables include the frequency of performing repositioning and using PSFs (tilt, recline, legrests and seat elevation), wheelchair occupancy, and driving distance. The Tool for Assessing Wheelchair disComfort (TAWC) were used to evaluate general discomfort and discomfort intensity.

Results: Spearman correlation coefficient showed that the frequency of using tilt, recline, and legrest is significantly correlated with discomfort intensity. Multiple regression analysis with backward stepwise indicated that these functions can explain 43.8% of the variance (R2?=?.438, F(3,33)?=?8.588, P?Conclusions: For people who used power wheelchairs equipped with PSFs, correlation analysis and regression modeling provided evidence from the quantitative data that increasing the frequency of using PSFs may decrease wheelchair discomfort. Future studies should include interventions to encourage people to use their PSFs appropriately.     

Seated lumbar/pelvic alignment. A comparison between spinal cord-injured and noninjured groups.

It has been postulated that loss of voluntary trunk stability, combined with the posture imposed by the configuration of the wheelchair seat, biomechanically necessitates that a person with diminished trunk control assume an abnormal sitting posture. This posture is characterized by a long, "C"-shaped kyphotic thoracolumbar spine, an extended cervical spine, a flattened lumbar spine, and a posteriorly tilted pelvis. If lateral trunk deformities are present, trunk imbalance and pelvic deformities in the coronal (frontal) plane can exist. This study has investigated the spinal/pelvic postural alignment of a limited sample of seated spinal cord-injured people and compared the results to a similar sample of able-bodied individuals seated in the same standardized positions. The results suggests that there are distinct differences in the spinal/pelvic alignment between the two study groups. These differences and the movements that take place in the pelvic structures during active wheelchair sitting have implications relative to pressure sore prevention and postural management.     

A motor learning approach to training wheelchair propulsion biomechanics for new manual wheelchair users: A pilot study

Context/Objective: Developing an evidence-based approach to teaching wheelchair skills and proper propulsion for everyday wheelchair users with a spinal cord injury (SCI) is important to their rehabilitation. The purpose of this project was to pilot test manual wheelchair training based on motor learning and repetition-based approaches for new manual wheelchair users with an SCI.

Design: A repeated measures within-subject design was used with participants acting as their own controls.

Methods: Six persons with an SCI requiring the use of a manual wheelchair participated in wheelchair training. The training included nine 90-minute sessions. The primary focus was on wheelchair propulsion biomechanics with a secondary focus on wheelchair skills.

Outcome Measures: During Pretest 1, Pretest 2, and Posttest, wheelchair propulsion biomechanics were measured using the Wheelchair Propulsion Test and a Video Motion Capture system. During Pretest 2 and Posttest, propulsion forces using the WheelMill System and wheelchair skills using the Wheelchair Skills Test were measured.

Results: Significant changes in area of the push loop, hand-to-axle relationship, and slope of push forces were found. Changes in propulsion patterns were identified post-training. No significant differences were found in peak and average push forces and wheelchair skills pre- and post-training.

Conclusions: This project identified trends in change related to a repetition-based motor learning approach for propelling a manual wheelchair. The changes found were related to the propulsion patterns used by participants. Despite some challenges associated with implementing interventions for new manual wheelchair users, such as recruitment, the results of this study show that repetition-based training can improve biomechanics and propulsion patterns for new manual wheelchair users.