Disability and Rehabilitation: Assistive Technology
ISSN: 1748-3107 (Print) 1748-3115 (Online) Journal homepage: http://www.tandfonline.com/loi/iidt20
Do tilt-in-space wheelchairs increase occupational engagement: a critical literature review Jenny Harrand & Katrina Bannigan To cite this article: Jenny Harrand & Katrina Bannigan (2014): Do tilt-in-space wheelchairs increase occupational engagement: a critical literature review, Disability and Rehabilitation: Assistive Technology To link to this article: http://dx.doi.org/10.3109/17483107.2014.932021
Published online: 27 Jun 2014.
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Date: 05 November 2015, At: 22:51
http://informahealthcare.com/idt ISSN 1748-3107 print/ISSN 1748-3115 online Disabil Rehabil Assist Technol, Early Online: 1–10 ! 2014 Informa UK Ltd. DOI: 10.3109/17483107.2014.932021
REVIEW PAPER
Do tilt-in-space wheelchairs increase occupational engagement: a critical literature review Jenny Harrand1 and Katrina Bannigan2
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1
Wheelchair Services Department, Northern Lincolnshire and Goole Hospitals NHS Foundation Trust, Diana, Princess of Wales Hospital, North East Lincolnshire, UK and 2Research Centre for Occupational and Mental Health, York St John University, York, UK Abstract
Keywords
Purpose: A wheelchair can enhance the quality of life of an individual with limited mobility, poor trunk control and stability, by enabling activity and participation and so occupational engagement. High specification wheelchairs which can tilt-in-space enable the position of users to be altered to suit activity and context. Despite tilt-in-space wheelchairs being expensive little is known about their therapeutic value. Methods: A critical literature review of the evidence was undertaken to evaluate whether the use of tilt-in-space increases occupational engagement. A wide ranging search strategy identified 170 articles which were screened using inclusion criteria. The eligible literature (n ¼ 6) was analysed thematically using open coding. Results: The majority of the participants used tilt-in-space but the data was too heterogeneous to combine. Measures of occupational engagement were not used so the therapeutic value could not be assessed. Conclusion: There is a lack of high quality evidence about the therapeutic benefits of tilt-in-space wheelchairs. Given the expense associated with providing these wheelchairs, and the increase in their provision, research is needed to justify provision of high specification wheelchairs to meet the occupational needs of users within the limited resources of health and social care.
Occupation, participation, tilt, tilted, tilting, variable position, varying position, wheelchair History Received 13 March 2014 Revised 25 May 2014 Accepted 03 June 2014 Published online 27 June 2014
ä Implications for Rehabilitation
Tilt-in-space wheelchairs. Wheelchairs are an important and essential assistive device for promoting independence and function. Suggests there are benefits for tilt-in-space wheelchairs. Identifies the need for additional large scale research.
Introduction and background Most people have complex lifestyles and participate in a variety of activities requiring an ability to alter their physical position to suit context. This means for many individuals the ability to perform and ultimately engage in occupations is limited, or prevented, due to a lack of mobility and may be further impeded by poor trunk control and stability. For those individuals with reduced functional abilities, the use of a wheelchair may become the essential component for enabling them to live their lives in a meaningful way. Wheelchairs facilitate movement through and into differing environments and for some provide a support mechanism while completing static or dynamic tasks and activities [1].
Address for correspondence: Jenny Harrand, Senior Wheelchair and Special Seating Occupational Therapist, Northern Lincolnshire and Goole Hospitals NHS Foundation Trust, Wheelchair Services Department, Diana, Princess of Wales Hospital, Scartho Road, Grimsby, North East Lincolnshire DN33 2BA, UK. E-mail: [email protected]
In the UK, occupational therapists in wheelchair services work with people with reduced functional abilities to identify which style and configuration of wheelchair will provide them with the greatest opportunity for continued participation in life’s occupations and activities. This requires the occupational therapist to gain sufficient knowledge and understanding of an individual’s posture, skin integrity, daily living, functional, social, leisure and domestic goals to enable the identification and selection of the most appropriate specification of wheelchair to facilitate all functional, participatory activities and occupations [2,3]. The market provides various wheelchair configurations, which can be tailored to meet individual needs. For some individuals, a standard or basic configuration will enable them to fully engage in their everyday activities. However, others will require more bespoke or complex configurations in order to achieve and support their optimal seated position to enable maximum function and prevent pressure damage [4,5]. Wheelchairs that fail to meet the requirements of its user, functionally, socially and environmentally, could have a negative impact upon quality of life and community inclusion [6].
2
J. Harrand & K. Bannigan
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Types of wheelchair The style of wheelchairs that are typically available via the NHS within the UK include: attendant push or self-propel which can be of a standard or lighter-weight design, active use and electric (powered). Accessories for these wheelchairs can include: a wide variety of pressure relieving cushions, cushions which provide both pressure relief and positioning options, backrests and canvasses, positioning belts, harnesses and headrests. For those with complex seating needs interfacing bespoke modular seating systems or moulded seat inserts (MSI) onto a wheelchair base is an alternative option [5] as is the use of recline, static tilt and tilt-in-space [5,7]. (a) Recline (Figure 1), can be static, manually (usually hydraulic) or power operated. With recline, the seat base remains static while the backrest lowers widening the hip angle [5,8]. Reported uses include increasing the interface surface area, accommodating fixed postural deformity such as posterior pelvic tilt and bladder management [2,7,8]. Contraindications include an increase in friction and shear forces [7] and changes in the position of lateral supports causing pressure under the axilla. (b) Static tilt is achieved via the use of accessories such as back cushions and canvases, alternative back post/frame angles and/or in conjunction with the position of the castor, castor fork and rear axle plate heights dependent upon whether positive (backward/bucket) or negative (forward/perched) tilt is required (Figures 2 and 3). (c) Tilt-in-space (Figure 4) involves a change in negative (forward) or positive (backward) orientation [7] and is available for high specification wheelchairs. The use of mechanical or powered tilt-in-space enables the reorientation of the seat, including head and foot position, while maintaining the desired optimal seated position [2,9]. Tiltin-space can reduce the effects of shear and friction on skin integrity compared to reclining [5,8]. The cost of providing wheelchairs, particularly those with a higher specification such as tilt-in-space, can be expensive. For example, in the UK, dependent upon supplier and price banding, a standard attendant push or self-propel wheelchair can cost the NHS around £150 ($230). A manual wheelchair base with or without the tilt-in-space function costs approximately £600 to £1500 ($900–$2300). Whereas an electrically operated powered indoor/outdoor wheelchair with powered tilt-in-space are available from around £1500 ($4540). In the UK, it is unclear whether there has been an increase in the provision of tilt-in-space wheelchairs over time.
Figure 1. Recline – which can be static, manually or power operated.
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However, the overall demand for wheelchairs is likely to have risen due to changes in public opinion and policy related to community participation and social inclusion. With this in mind, a strong evidence base for the therapeutic benefits of tilt-in-space is needed to justify the additional costs associated with the provision of wheelchairs with this function. Furthermore, due to what is described as a poor level of understanding by some clinicians, tiltin-space and recline are commonly prescribed to accommodate the same purposes [5,7] suggesting the need for clarity of purpose and benefits within the evidence base. A preliminary search of the literature identified a large volume of information related to the assessment, provision and use of wheelchairs which, on face value, appeared to support the use of tilt-in-space. However, a report synthesising all of the available research data regarding the use of tilt-in-space wheelchairs could not be sourced. Therefore, the need for a critical literature review was indicated. The aim was to evaluate research underpinning the use of tilt-in-space wheelchairs and including whether occupational engagement is enhanced. Literature review Using the expert guidance from a clinical librarian, a wide ranging electronic search strategy was undertaken (Table 1); additional search methods included hand, citation and author searching. After excluding duplicates, all of the remaining titles
Figure 2. Static tilt achieved with ramped cushion and tension adjustable back canvas.
Figure 3. Static tilt achieved by adjusting the height of castors and rear wheel axle plate.
Tilt-in-space wheelchairs
DOI: 10.3109/17483107.2014.932021
3
Table 2. A summary of the inclusion and exclusion criteria. Inclusion Research studies 1980 to current Any age (participant) Any condition (participant) Available in English language Wheelchairs with mechanical or powered tilt-in-space that are utilised in everyday activities Field-based studies
Exclusion Pre-1980 Literature that is not research based Product or equipment focus Research focussed on static tilt Research focussed on pressure care alone Laboratory-based research
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Overview of the research
Figure 4. Tilt-in-space – which can be static, manually or power operated.
Table 1. A summary of the electronic search strategy undertaken. Electronic databases
Search terms
Search parameters
AMED Bandolier BNI Cochrane CINAHL DARE/NHSeed/HTA Google Scholar MEDLINE NHS Evidence OT Seeker PEDro PsychINFO Social Care Online
Wheelchair* AND (tilt* OR tilt-in-space OR var* position)
Publication years 1980 ! current Search title and abstract to refine literature sourced
and abstracts were checked for relevance using the inclusion and exclusion criteria outlined in Table 2. Research focused within a laboratory setting was excluded as the artificial environment of the laboratory would not reflect the study’s focus on everyday life experiences and occupations. All of the included studies were subjected to a quality assessment and data were extracted. Though ethical approval is not required for the completion of a literature review, the level of ethical reporting within the included papers was reviewed. Due to the heterogeneous nature of the included studies a narrative overview was used to analyse the data.
That only six studies could be included in this review, and all of them were small, exploratory studies (Table 3), shows that this is an under researched area particularly within the UK. Only one [9] study was conducted in the UK and the remaining five were from the USA. All of the participants were adult tilt-in-space wheelchair users with differing neurological diagnoses (Table 3). Three explored the use of tilt-in-space [1,9,12], one studied tilt-in-space and recline [10] with the remaining two evaluating tilt-in-space, recline and seat elevation [11,13]. All of the studies, except one [13], delineated the number of participants with either the tilt-in-space and/or recline and seat elevation functions (Table 3). Two of the studies [10,11] combined the functions tilt-in-space and recline into one statistic when reporting their findings. This made direct comparisons between the six studies difficult because they were too heterogeneous to combine, hence the use of a narrative overview for this research. The extent to which the studies explored the use of tilt-in-space wheelchairs in everyday life varied. The outcome measures included a range of digital monitoring systems and questionnaires. The digital monitoring systems, fitted to participants wheelchairs in four of the studies [1,11–13], were designed to scientifically measure and then analyse how frequently and for how long the participants utilised tilt-in-space, recline or seat elevation during the day (Table 3). Similarly, the data analysis in the fifth study [10] also produced data with a focus on frequency of use and the tilt-in-space and recline utilisation range. Although some detail was provided on the specific tasks, the tilt-in-space function was used for, this did not fully reflect its effect on activity and participation, even though this is important for understanding the impact of these wheelchairs on the everyday lives of the people who use them.
Narrative overview Facilitating activity and participation
Findings
Combined use of tilt-in-space and recline functions
In total, 997 hits were obtained following completion of the search strategy; after screening for duplicates the remaining 170 hits were relevance checked using the inclusion and exclusion criteria (Table 2). This process resulted in only six papers [1,9–13] being included for the quality assessment, data extraction (Table 3) and the development of the narrative overview. Papers excluded from the study involved those whose research focused on standard powered or manual wheelchair provision [14], static tilt and/or pressure care [15,16], posture [17] or wheelchair stability [18,19]. Following the convention of qualitative report writing the narrative overview is reported and discussed concurrently.
One study [10], identified an excellent level of participant satisfaction with several commenting that the opportunity to adjust seating orientation enabled them to complete their daily activities and maintain functional independence. In this study [10], 97.5% of the participants were found to utilise their repositioning systems daily. Others [11,13] reported the daily use of the tilt-in-space and recline functions, with tiltin-space used more frequently than recline [13]. While some participants significantly orientated themselves into a tilted position compared to the time spent in an upright position [11]. However, this study [11] also reports that its participants did not utilise the recline or seat elevation functions more than
Dewey et al. [9]
Lacoste et al. [10]
Citation
Focus
Aim: To explore and compare the experience of tilt-in-space wheelchair use and conventional wheelchair use in severely disabled clients with multiple sclerosis and significant spasticity.
Tilt-in-space versus conventional wheelchairs
Aim: To determine the use of specific types of repositioning systems, the frequency and range of use and global satisfaction level
Powered tilt and recline systems
Table 3. Data extraction table.
Phenomenology
Exploratory evaluation (Pilot study)
Research design
Diagnosis Multiple sclerosis
Age mean 55.5 years (range 35–71)
Yes
Yes
Hospital anxiety and depression scale and short orientation memory test (to assess mental state)
After the interview: Modified Barthel index (to assess met criteria to be included in study)
In-depth interviews, with guided interview schedule, in their home Carers present in n¼17 interviews
Participants were assessed in their home by an occupational therapy student
The important reasons for using the powered wheelchair were also ranked
Questionnaire assessed each item for Frequency of use Range of tilt Range of recline, and Satisfaction levels
A 25-item questionnaire developed using a literature review and two focus groups –[one with service users (n ¼ 5) and one with professionals (n ¼ 4)]. No reliability or validity testing
Data collection (including outcome measure)
(continued )
Benefits of tilt-in-space are comfort, improved postural support, enhanced seating stability, relief of pressure, rest out of bed for prolonged periods Difficulties tilt-in-space wheelchairs are bulky and lack manoeuvrability
Short orientation memory test (n ¼ 19) Mean score 22.3 (range 10–28)
Hospital anxiety and depression scale (n ¼ 19) Mean score 5.6 (range 0–16)
Modified Barthel index Mean score 4.6 (range 0–17)
Wheelchair Tilt-in-space (n ¼ 7) manual (n ¼ 2) powered (n ¼ 5) Conventional (n ¼ 16)
Important reasons for use Increase comfort, rest, reduced discomfort, bladder draining
Satisfaction levels 99% satisfaction rate
Range of tilt/recline Range of amplitudes used
Frequency of use All use. 97.5% use everyday
Risk of type II error
Wheelchair Tilt-in-space (n ¼ 26) Recline (n ¼ 10) Both (n ¼ 4)
Results
J. Harrand & K. Bannigan
Men (n ¼ 10) and women (n ¼ 13)
Response rate ¼ 88% (Three declined n reasons provided)
Diagnosis Neuromuscular disease (n ¼ 11) MS (n ¼ 17) Spinal cord injury (n ¼ 6) Other (not stated) (n ¼ 6) Convenience sampling of adults with multiple sclerosis and spasticity who were full time wheelchair users recruited through three wheelchair services. N ¼ 23
Age mean 46 years (range 21–69)
Men (n ¼ 32) and women (n ¼ 8)
Response rate ¼ 66.7%
N ¼ 40
Adults who owned a powered wheelchair with tilt-in-space and/or recline for at least one year who were recruited randomly from two rehabilitation centres in Montreal
Sample
Ethical approval secured
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4 Disabil Rehabil Assist Technol, Early Online: 1–10
Sonenblum et al. [12]
Ding et al. [11]
Citation
Aim: To describe the use of the power tilt systems in everyday life
Powered tilt-in-space
Aim: To examine the use of powered seating function including tilt-in-space, backrest recline, and seat elevation of wheelchair users during their typical daily activities
Tilt-in-space, recline and seat elevation
Focus
Descriptive study
Descriptive study
Research design
Age 22–69 years
Men (n ¼ 11) and women (n ¼ 5)
Convenience sample of adults who use tilt-in-space wheelchairs only N ¼ 16 Diagnosis Spinal cord injury (n ¼ 10) Cerebral palsy, cerebral vascular accident, muscular dystrophy, juvenile parkinsonism (no figures) Injured/diagnosed less than year (n ¼ 3); range was 2–59 years (median ¼ 6 years)
Diagnosis Muscular dystrophy (n ¼ 1) Spinal cord injury (n ¼ 4) Cerebral palsy (n ¼ 3) Multiple sclerosis (n ¼ 3)
Age mean 44.4 ± 14.5 years
Men (n ¼ 6) and women (n ¼ 5)
Response rate ¼ 92% (one response not reliable)
N ¼ 11
Convenience sample of adults who used a powered wheelchair independently referred by Human Engineering Research Laboratories wheelchair user registry or through a rehabilitation centre
Sample
Yes
Yes
Ethical approval secured
Wheelchair activity monitoring instrument (WhAMI)
Self-reporting questionnaire – little information given
End of study completed a selfreport questionnaire; no details about the tool
Used for two weeks
Seating function data logger (SFDL) developed for study which was mounted on wheelchair without modification and did not interfere with activities of daily living
Data collection (including outcome measure)
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(continued )
Median was 3.1 (±SD 4.3 ¼ /3.9) tilts per hour of wheelchair occupancy
Typical position Variety including typically sat at small tilt (0–14 ) and medium tilt (15–29 ) but few went past 45
Wheelchair occupancy 11 h (range 5–16.6) per day
Risk of type II error
Reasons for use ¼ reach higher levels, shop, sit at the bar, socialise, eat, read the calendar on the fridge, reach elevator buttons Wheelchair Only tilt-in-space included (recline excluded)
Correlation between selfreported and actual use not significant
Occupied wheelchair for 11.8 ± 3.4 h per day Transferred in and out 5.0 ± 5.3 times per day Accessed tilt-in-space 19 ± 4 times per day Stayed in tilt/recline 39.3% ± 36.5% of their time each day Changed positions every 53.6 ± 47 min
Wheelchair Tilt-in-space (N ¼ 11) Recline (n ¼ 9) Elevation (n ¼ 9)
Results
DOI: 10.3109/17483107.2014.932021
Tilt-in-space wheelchairs 5
Aim: To determine the features most frequently selected in a power wheelchair, level of satisfaction with the selections, and frequency of use
Power wheelchair; tilt-in-space, recline, seat elevation
To explore the use of PAMS to assess health, activity and participation with use of tilt-inspace wheelchairs.
Tilt-in-space
Focus
Retrospective survey
Pre-test–post-test study
Men (n ¼ 27) and women (n ¼ 18)
Response rate ¼ 71% (n ¼ 32)
Convenience sample (N ¼ 45) of adults with Amyotrophic Lateral Sclerosis/ Motor Neurone Disease who were current patients and powered wheelchair users
Diagnosis Cerebral Palsy Dystonia Muscular dystrophy Multiple sclerosis Spinal Cord Injury
Age range 30–60 years.
Men (n ¼ 1) and women (n ¼ 4)
Response rate ¼ 71% (n ¼ 5)
N¼7
Convenience sample of adults who have been issued with a powered tilt-in-space wheelchair.
Sample
Sought ethics approval – not required
Outcome measures conducted at:
Yes
Scores from the Amyotrophic Lateral Sclerosis Functional Rating Scale-Revised (ALSFRS-R) were collected
Developed by author (no details provided)
Semi structured, prompted recall interview Postal questionnaire 31-items
Community Participation and Perceived Receptivity Scale (self-reported)
Three months SF-8 (self-reported)
Use of chair Participatory and activity measurement system (PAMS) – Multipurpose data logger designed for the study GPS
Community Participation and Perceived Receptivity Scale (self-reported)
Baseline SF-8 (self-reported)
Consent and basic health questionnaire
Data collection (including outcome measure)
Ethical approval secured
(continued )
Level of satisfaction 88% were satisfied with their chair
Features most liked Leg rest, cushion, headrest
Wheelchair Tilt-in-space, recline, seat elevation but does not state numbers of participant using each type
Community destinations visited 3–29 over two weeks but little difference between pre–post test.
Changed positions – the frequency they did this varied.
Distances increased (n ¼ 3)
All used tilt system daily
SF-8 (self-reported) All showed improvements Physical and mental health (n ¼ 3) Only physical or mental health (n ¼ 2)
Self-reported reasons for use comfort / discomfort/pain rest / relaxation Wheelchair Powered tilt-in-space
Tilt frequency Few performed pressure relieving tilts Median ¼ 0.13 per hour.
Results
J. Harrand & K. Bannigan
Ward et al. [13]
Harris et al. [1]
Citation
Research design
Table 3. Continued
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6 Disabil Rehabil Assist Technol, Early Online: 1–10
Tilt-in-space wheelchairs
Focus Citation
Diagnosis Amyotrophic lateral sclerosis/ motor neurone disease
Age mean 57.9 years (range 27–85)
No difference for tilt, recline and power elevating leg rests
Frequency of use Increased use of seat elevator and attendant control
81% thought the chair was good value for money
Data collection (including outcome measure) Sample
Ethical approval secured Research design
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Results
DOI: 10.3109/17483107.2014.932021
7
the tilt-in-space though significant differences were found in relation to the most frequently utilised tilt and recline angles available. Use of tilt-in-space function Three studies reported the daily use of the tilt-in-space function [1,11,12] with smaller amplitudes of tilt selected more frequently than the medium, large or extreme tilts available; however, no significant differences in tilt-in-space use was found over time [12,13]. Two studies [10,12] reported participants achieving some functional independence, with one of these studies specifically referring to the facilitation of transfers, personal hygiene, access under tables and eating [10]. However, it is difficult to draw conclusions because the first study [10] combined the use of tiltin-space with recline, whereas the wheelchairs in the second study [12] are fitted with the tilt-in-space function only. Similarly, the ability to draw conclusions is difficult in relation to the studies which report on bladder and bowel movements [9,10]. The participants in the first study [9] with tilt-in-space wheelchairs reported the ability to use tilt assisted with their bladder drainage, whereas the participants in the second study [10] with both the tilt-in-space and recline functions reported utilisation of the recline more than the tilt-in-space function to achieve bladder drainage and use of the tilt-in-space function eased bowel movement. Where the distance travelled by participants within the local community was assessed, following provision of a tilt-in-space wheelchair, it was found that three of the five participants did increase their travel distance [1]. One of the participants within this study whose travel distance declined was attributed to seasonal temperature changes. It was reported that despite community and activity levels not being significantly affected by tilt-in-space, there did appear to be improvements in perceptions of physical and mental health [1]. Compared to a study which took place in the USA [1], the UK study [9] found the ability to complete activities within home, such as in the kitchen and with accessing local transport links and the community, was hampered by the size, weight and manoeuvrability of tilt-in-space wheelchairs. Difficulties with access to the home and community environments can be accommodated, up to a point, by mid-wheel drive powered wheelchairs which have a greater capacity for turning within its own space [13]. However, the provision of these wheelchairs, via the NHS in the UK, is dependent on local guidelines and provision criteria and so are not necessarily universally available. Two of the studies [11,12] found that despite the frequent use of the tilt-in-space function, which can be used to facilitate the recommended angles of pressure relieving tilt, the participants involved were not following the USA repositioning or pressure care guidelines. This suggested there is a need for better training and awareness [12]. Interestingly, the participants in the UK study [9], reported that the provision of a pressure cushion would protect them from the development of pressure wounds; only one participant demonstrated knowledge of the potential risks involved of remaining in a static position without completing some form of pressure relief. One study [9] made particular reference to the devastating impact the development of a pressure wound can have in relation to the ability to participate in activities and subsequent effect on quality of life. Individuals who are unable to reposition themselves due to poor core stability, functional ability and/or have altered sensation are at risk from developing a number of postural deformities, for example: postural kyphosis, posterior pelvic tilt, chin poke, neck hyperflexion or extension, scoliosis, obliquity and rotation of the
8
J. Harrand & K. Bannigan
spine and pelvis [5,20]. The effect of postural changes can lead to increased pressure loading resulting in the development of pressure ulcers with the combined effect of increased pain and discomfort, physiological complications and loss of functional independence [5]. Of the six studies included, two found that participants utilised the tilt-in-space feature to reduce the effects of sliding [9,10], whereas some participants utilised the tilt-inspace and/or the recline features to improve stability and balance [10]. Overall, the positive impact of tilt-in-space, and/or recline, experienced by the participants within the six studies includes: breathing [10], napping, resting or relaxing [9,10,13], comfort [1,9–11,13], the opportunity to spend greater amounts of time outoff bed [9], pain management [1,10,12], pressure relief tilts [1,10– 12] and a decrease in spasms [9].
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Occupational engagement and quality of life Although all six articles reported the intention of exploring the use of tilt-in-space, recline and/or seat elevation in relation to everyday life, the research did not focus on occupational engagement and the impact of this on the participants. For example, where the number of community destinations was explored and found to have increased [1], the research does not appear to further examine what if any specific activities were then accessed and what the impact or meaning of this was to the individual. For instance if, following provision of a wheelchair with the tilt-in-space and/or recline functions, pain was reduced and comfort improved, the ability to tolerate remaining at a destination may have increased so enabling the person using the wheelchair to participate in desired activities for extended time periods with the overall effect of enhancing occupational engagement. It is suggested that clinical perceptions of importance may differ significantly between health care professionals and the people they work with [9]. When considering community access (a shop), the clinician or researcher may consider that occupational engagement has been achieved, whereas from the perspective of the patient occupational engagement is enhanced by the activity itself (shopping). Of the six studies included in this review, five made a direct reference to the term quality of life [1,9,10,12,13]. One study concluded that quality of life could be an outcome measured via self-reporting tools [1]. Another highlighted that quality of life is one of the important elements to consider when assessing the mobility needs of individuals [13]. A small sample size and the diagnosis of participants (deteriorating neurological) were the reasons provided by one study for not including this issue within their study [9]. Recognising that quality of life is not necessarily directly included within a medical needs assessment, one study suggested that quality of life could be measured as part of participation and activity outcomes generally [12], whereas the fifth study [10] only referred to quality of life within their introduction and literature review. Although not all of the studies reported their findings using comparable data, and frequently combined the use of the differing functions [10,11,13], the implication overall is that the use of tiltin-space and/or recline may have therapeutic benefits. The studies do not provide clear indications as to whether the participants were able to participate in a greater number and variety of activities over extended periods of time, or, what the overall impact this may have had on occupational engagement or quality of life issues. The studies do not provide clear indications as to whether the participants were able to participate in a greater number of activities and/or whether for extended periods of time, what these activities were and the overall impact this may have had on occupational engagement or quality of life issues.
Disabil Rehabil Assist Technol, Early Online: 1–10
Quality assessment A number of issues have arisen from this research related to validity. All six were small exploratory studies (Table 3), with only one study [11] making reference to the use of a power analysis to determine sample size. Across the six studies a wide range of data collection methods were used including differing self-reported questionnaires and digital monitoring systems. With the use of retrospective questionnaires comes the potential for recall bias, which was acknowledged in one of the studies [13]. Some of the included studies collected data over short time span, which could have reflected poorly upon the usage patterns of wheelchairs [1,10–12]. The methods utilised by all six of the studies were poorly described affecting the ease of replication and three of the studies did not always distinguish between those participants using tilt-in-space and/or recline wheelchairs [10,11,13]; an issue which contributes to the heterogeneity of this review. Ethical approval was secured by five of the studies [1,9–12] with the sixth [13] reporting that the review board they approached stated ethical and informed consent was not required due to the nature of their study. Flaws were identified in the limitations of four of the studies, particularly with sampling and recruitment [1,10,11,13]; challenges which, in part, contributed to the small sample sizes. For example, one study [10] had intended to recruit 30 participants to each group with either the tilt-in-space or recline functions; the number of participants who consented to participate totalled 40 with combined or unevenly spread functions. The challenges raised here suggest that sampling and recruitment is an issue requiring attention when designing future studies. It was suggested that the limits set to measure function usage, via the digital monitoring systems, may have been less than optimal [11]. Two of the studies raised the issue of sampling bias in relation to participant diagnosis [10,12], with one suggesting that the variance in conditions may have biased their findings [10]. Although the quality assessment raises questions of the overall rigour of the included studies, collectively the studies’ findings raise several valid points for discussion and future consideration. Examples include: the benefits of combining subjective (questionnaires, interviews) and objective (digital monitoring systems) data collection methods [1], the importance of gathering information directly from the patient’s (participants) perspectives [13]. Perhaps service users should be involved in the design of future studies. Although this review has failed to firmly establish or refute the clinical or therapeutic benefits of tilt-inspace (and/or other functions such as recline) wheelchairs, the conclusions of the studies reviewed do indicate that with robust research methods the benefits are more likely to outweigh the disadvantages. Implications for practice The above quality assessment demonstrates that the findings of the included studies cannot be translated into practice and should be interpreted cautiously. The findings do suggest that tilt-inspace outcomes should be researched further. For example, the findings from one study [10] suggests the tilt-in-space and recline functions were important to their participants because without them independence would have been affected. However, this would need to be tested in more detail to determine whether this statement stands up to the scrutiny of the larger population of wheelchair users. Given the problems that can arise with postural deformity and skin integrity through poor positioning, and by not following repositioning guidance, practitioners should consider whether the levels of training and education currently provided are appropriate or adequate.
Tilt-in-space wheelchairs
DOI: 10.3109/17483107.2014.932021
At present, the question of whether tilt-in-space wheelchairs benefit those who use them remains unanswered. It could be suggested that during the assessment, training and hand-over phases of tilt-in-space wheelchair provision, greater emphasis is placed on how and why these functions may assist individuals to complete various tasks and activities, including daily living, posture and pressure care. A uniform and robust method of measuring outcomes and reviewing provision in the long term is a first step in the process of developing the evidence base for their effectiveness in relation to occupational performance, engagement and quality of life. Opportunities for integrated multi-professional working should be explored to ensure, amongst other things, the consistency of advice given and the joint funding and pooling of budgets ensures that increasingly limited resources are used judiciously.
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Implications for future research This review has highlighted a number of issues for those planning to conduct future research into tilt-in-space wheelchairs to consider. Suggestions include: larger studies with broader recruitment, for example, the inclusion of paediatric patients, a wider range of diagnoses across both adult and paediatric participants, and involving a number of wheelchair services to ensure sufficiently powered studies. The functions tilt-in-space, recline and seat elevation should be researched within the same studies but must be approached in such a way that direct comparisons can be drawn. The focus of the research should be relevant and clearly represent both the interests of the users and the service outcomes. Allowing sufficient time for data collection to reflect usage patterns will be a key factor in the planning process. Appropriate, valid and reliable instrumentation including occupational performance measures and digital monitoring systems should be used to capture data. Given the urgent need for research in this field within the UK, perhaps key stakeholders such as the Posture and Mobility Group, the National Wheelchair Managers Forum and the Regional Wheelchair Therapists and Rehabilitation Engineer Specialist Interest Groups could collectively design and conduct a large scale study that will generate sufficient power to inform policyholders and commissioning bodies. At the very least, agreeing outcomes of interest would ensure homogeneity between any future studies. A multi-professional research design would potentially capture and reflect the views of occupational therapists, physiotherapists, rehabilitation engineers, nurses, and speech and language therapists which, alongside those of the patients involved, would provide a rich pool of data for analysis. As the core philosophy of occupational therapy is the promotion of independence through activity and occupation, it would be in the profession’s interest to be at the forefront of such an extensive research project. It is suggested that the most rigorous form of research, a Randomised Control Trial to reduce confounding factors within the research process and protocol are minimised [21–23], is used as the study design. However, the use of a randomised control or clinical trial to determine the effectiveness of mobility devices may be difficult [16] unless a pragmatic approach is used; for example, using a waiting list control group. Limitations of the review Although a wide-ranging search strategy was implemented, resource constraints meant it was not possible to search for grey literature or non-English language studies, which may have contributed to this review. The relevance checking and thematic analysis were completed by a single researcher with subject
9
expertise following inclusion and exclusion criteria which were developed a priori. The numbers involved suggest fatigue is unlikely to have been an issue when relevance checking. The second author checked data extraction of the included papers and so was able to assess that the thematic analysis reflected the data rather than the researcher’s assumptions.
Conclusion This review has identified a lack of high quality evidence about the benefits of wheelchairs with the tilt-in-space function and is therefore unable to make any specific recommendations for best practice other than to suggest the potential need for improved training and education. The conclusions of the included studies implied that there are potential benefits of tilt-in-space wheelchairs but that further research is required to support their findings. Although the lack of evidence is not evidence of no effect, given the expense associated with providing wheelchairs with the additional functions of tilt-in-space and/or recline and seat elevation, the ability to continue justifying limited resources to the provision of higher specification wheelchairs is questionable. The need for further research of a sufficient quality to guide clinical practice is therefore indicated.
Declaration of interest The authors report no conflicts of interest. The authors alone are responsible for the content and writing of this article. This study was completed as part of the requirement for the degree of MSc in Professional Health and Social Care Studies at the Facility of Health and Life Sciences, York St John University in conjunction with the Research Centre for Occupation and Mental Health.
References 1. Harris F, Sprigle S, Sonenblum SE, Maurer CL. The participation and activity measurement system: an example application among people who use wheeled mobility devices. Disabil Rehabil: Assist Technol 2010;5:48–57. 2. Collins F. The Ibis XP tilt-in-space powered wheelchair: a review. Int J Ther Rehabil 2005;12:510–14. 3. Finucane C. Choosing a suitable powered wheelchair: a guide. Int J Ther Rehabil 2006;13:87–9. 4. Batavia M. The wheelchair evaluation: a practical guide. Boston: Butterworth-Heinemann; 1998. 5. Pope PM. Severe and complex neurological disability: management of the physical condition. Philadelphia (PA): ButterworthHeinemann; 2007. 6. Di Marco A, Russell M, Masters M. Standards for wheelchair prescription. Aust Occup Ther J 2003;50:30–9. 7. Dicianno BE, Arva J, Liebermann JM, et al. RESNA position on the application of tilt, recline, and elevating leg rests for wheelchairs. Assist Technol 2009;21:13–22. 8. Sprigle S, Maurer C, Sonenblum SE. Load redistribution in variable position wheelchairs in people with spinal cord injury. J Spinal Cord Med 2010;33:58–64. 9. Dewey A, Rice-Oxley M, Dean T. A qualitative study comparing the experiences of tilt-in-space wheelchair use and conventional wheelchair use by clients severely disabled with multiple sclerosis. Brit J Occup Ther 2004;67:65–74. 10. Lacoste M, Weiss-Lambrou R, Allard M, Dansereau J. Powered tiltrecline systems: why and how are they used? Assist Technol 2003; 15:58–68. 11. Ding D, Leister E, Cooper RA, et al. Usage of tilt-in-space, recline and elevation seating functions in natural environment of wheelchair users. J Rehabil Res Develop 2008;45:973–83. 12. Sonenblum SE, Sprigle S, Maurer CL. Use of power tilt systems in everyday life. Disabil Rehabil: Assist Technol 2009;4:24–30. 13. Ward AL, Sanjak M, Duffy K, et al. Power wheelchair prescription, utilization, satisfaction, and cost for patients with Amyotrophic
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J. Harrand & K. Bannigan Lateral Sclerosis: preliminary data for evidence-based guidelines. Arch Phys Med Rehabil 2010;91:268–72. May M, Rugg S. Electrically powered indoor/outdoor wheelchairs: recipients’ views of the effects on occupational performance and quality of life. Brit J Occup Ther 2010;73:2–12. Jan YK, Jones MA, Rabadi MH, et al. Effect of wheelchair tiltin-space and recline angles on skin perfusion over the ischial tuberosity in people with spinal cord injury. Arch Phys Med Rehabil 2010;91:1758–64. ˚ , Samuelson K, et al. Mobility devices to Salminen AL, Brandt A promote activity and participation: a systematic review. J Rehabil Med 2010;41:697–706. Hsieh CC, Hu MH, Lee SD, Wei SW. Exploration of factors related to wheelchair postural improvement in long-term care residents after an individualised wheelchair intervention. Assist Technol 2011;23: 1–12.
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18. Kirby RL, Heimrath O, Stewart A, et al. Effect of respiration on the static rear stability of wheelchairs. Arch Phys Med Rehabil 2010;91: 947–50. 19. Caldicott SJ, Shapcott N. Validation of a software-based stability assessment system for wheelchairs and their occupants. J Med Eng Technol 2008;32:440–7. 20. Hill S, Goldsmith J. Biomechanics and prevention of bodyshape distortion. Tizard Learn Disabil Rev 2010:15:15–29. 21. Evans D. Hierarchy of evidence: a framework for ranking evidence evaluating healthcare interventions. J Clin Nurs 2003;12:77–84. 22. Chambers R, Boath E, Rogers D. Clinical effectiveness and clinical governance made easy. 4th ed. Abingdon: Radcliffe Publishing; 2007. 23. Gerrish K. Evidence-based practice. In: Gerrish K, Lacey A, eds. The research process in nursing. 6th ed. Oxford: Wiley-Blackwell; 2010:488–99.
ISSN: 1748-3107 (Print) 1748-3115 (Online) Journal homepage: http://www.tandfonline.com/loi/iidt20
Do tilt-in-space wheelchairs increase occupational engagement: a critical literature review Jenny Harrand & Katrina Bannigan To cite this article: Jenny Harrand & Katrina Bannigan (2014): Do tilt-in-space wheelchairs increase occupational engagement: a critical literature review, Disability and Rehabilitation: Assistive Technology To link to this article: http://dx.doi.org/10.3109/17483107.2014.932021
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Date: 05 November 2015, At: 22:51
http://informahealthcare.com/idt ISSN 1748-3107 print/ISSN 1748-3115 online Disabil Rehabil Assist Technol, Early Online: 1–10 ! 2014 Informa UK Ltd. DOI: 10.3109/17483107.2014.932021
REVIEW PAPER
Do tilt-in-space wheelchairs increase occupational engagement: a critical literature review Jenny Harrand1 and Katrina Bannigan2
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1
Wheelchair Services Department, Northern Lincolnshire and Goole Hospitals NHS Foundation Trust, Diana, Princess of Wales Hospital, North East Lincolnshire, UK and 2Research Centre for Occupational and Mental Health, York St John University, York, UK Abstract
Keywords
Purpose: A wheelchair can enhance the quality of life of an individual with limited mobility, poor trunk control and stability, by enabling activity and participation and so occupational engagement. High specification wheelchairs which can tilt-in-space enable the position of users to be altered to suit activity and context. Despite tilt-in-space wheelchairs being expensive little is known about their therapeutic value. Methods: A critical literature review of the evidence was undertaken to evaluate whether the use of tilt-in-space increases occupational engagement. A wide ranging search strategy identified 170 articles which were screened using inclusion criteria. The eligible literature (n ¼ 6) was analysed thematically using open coding. Results: The majority of the participants used tilt-in-space but the data was too heterogeneous to combine. Measures of occupational engagement were not used so the therapeutic value could not be assessed. Conclusion: There is a lack of high quality evidence about the therapeutic benefits of tilt-in-space wheelchairs. Given the expense associated with providing these wheelchairs, and the increase in their provision, research is needed to justify provision of high specification wheelchairs to meet the occupational needs of users within the limited resources of health and social care.
Occupation, participation, tilt, tilted, tilting, variable position, varying position, wheelchair History Received 13 March 2014 Revised 25 May 2014 Accepted 03 June 2014 Published online 27 June 2014
ä Implications for Rehabilitation
Tilt-in-space wheelchairs. Wheelchairs are an important and essential assistive device for promoting independence and function. Suggests there are benefits for tilt-in-space wheelchairs. Identifies the need for additional large scale research.
Introduction and background Most people have complex lifestyles and participate in a variety of activities requiring an ability to alter their physical position to suit context. This means for many individuals the ability to perform and ultimately engage in occupations is limited, or prevented, due to a lack of mobility and may be further impeded by poor trunk control and stability. For those individuals with reduced functional abilities, the use of a wheelchair may become the essential component for enabling them to live their lives in a meaningful way. Wheelchairs facilitate movement through and into differing environments and for some provide a support mechanism while completing static or dynamic tasks and activities [1].
Address for correspondence: Jenny Harrand, Senior Wheelchair and Special Seating Occupational Therapist, Northern Lincolnshire and Goole Hospitals NHS Foundation Trust, Wheelchair Services Department, Diana, Princess of Wales Hospital, Scartho Road, Grimsby, North East Lincolnshire DN33 2BA, UK. E-mail: [email protected]
In the UK, occupational therapists in wheelchair services work with people with reduced functional abilities to identify which style and configuration of wheelchair will provide them with the greatest opportunity for continued participation in life’s occupations and activities. This requires the occupational therapist to gain sufficient knowledge and understanding of an individual’s posture, skin integrity, daily living, functional, social, leisure and domestic goals to enable the identification and selection of the most appropriate specification of wheelchair to facilitate all functional, participatory activities and occupations [2,3]. The market provides various wheelchair configurations, which can be tailored to meet individual needs. For some individuals, a standard or basic configuration will enable them to fully engage in their everyday activities. However, others will require more bespoke or complex configurations in order to achieve and support their optimal seated position to enable maximum function and prevent pressure damage [4,5]. Wheelchairs that fail to meet the requirements of its user, functionally, socially and environmentally, could have a negative impact upon quality of life and community inclusion [6].
2
J. Harrand & K. Bannigan
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Types of wheelchair The style of wheelchairs that are typically available via the NHS within the UK include: attendant push or self-propel which can be of a standard or lighter-weight design, active use and electric (powered). Accessories for these wheelchairs can include: a wide variety of pressure relieving cushions, cushions which provide both pressure relief and positioning options, backrests and canvasses, positioning belts, harnesses and headrests. For those with complex seating needs interfacing bespoke modular seating systems or moulded seat inserts (MSI) onto a wheelchair base is an alternative option [5] as is the use of recline, static tilt and tilt-in-space [5,7]. (a) Recline (Figure 1), can be static, manually (usually hydraulic) or power operated. With recline, the seat base remains static while the backrest lowers widening the hip angle [5,8]. Reported uses include increasing the interface surface area, accommodating fixed postural deformity such as posterior pelvic tilt and bladder management [2,7,8]. Contraindications include an increase in friction and shear forces [7] and changes in the position of lateral supports causing pressure under the axilla. (b) Static tilt is achieved via the use of accessories such as back cushions and canvases, alternative back post/frame angles and/or in conjunction with the position of the castor, castor fork and rear axle plate heights dependent upon whether positive (backward/bucket) or negative (forward/perched) tilt is required (Figures 2 and 3). (c) Tilt-in-space (Figure 4) involves a change in negative (forward) or positive (backward) orientation [7] and is available for high specification wheelchairs. The use of mechanical or powered tilt-in-space enables the reorientation of the seat, including head and foot position, while maintaining the desired optimal seated position [2,9]. Tiltin-space can reduce the effects of shear and friction on skin integrity compared to reclining [5,8]. The cost of providing wheelchairs, particularly those with a higher specification such as tilt-in-space, can be expensive. For example, in the UK, dependent upon supplier and price banding, a standard attendant push or self-propel wheelchair can cost the NHS around £150 ($230). A manual wheelchair base with or without the tilt-in-space function costs approximately £600 to £1500 ($900–$2300). Whereas an electrically operated powered indoor/outdoor wheelchair with powered tilt-in-space are available from around £1500 ($4540). In the UK, it is unclear whether there has been an increase in the provision of tilt-in-space wheelchairs over time.
Figure 1. Recline – which can be static, manually or power operated.
Disabil Rehabil Assist Technol, Early Online: 1–10
However, the overall demand for wheelchairs is likely to have risen due to changes in public opinion and policy related to community participation and social inclusion. With this in mind, a strong evidence base for the therapeutic benefits of tilt-in-space is needed to justify the additional costs associated with the provision of wheelchairs with this function. Furthermore, due to what is described as a poor level of understanding by some clinicians, tiltin-space and recline are commonly prescribed to accommodate the same purposes [5,7] suggesting the need for clarity of purpose and benefits within the evidence base. A preliminary search of the literature identified a large volume of information related to the assessment, provision and use of wheelchairs which, on face value, appeared to support the use of tilt-in-space. However, a report synthesising all of the available research data regarding the use of tilt-in-space wheelchairs could not be sourced. Therefore, the need for a critical literature review was indicated. The aim was to evaluate research underpinning the use of tilt-in-space wheelchairs and including whether occupational engagement is enhanced. Literature review Using the expert guidance from a clinical librarian, a wide ranging electronic search strategy was undertaken (Table 1); additional search methods included hand, citation and author searching. After excluding duplicates, all of the remaining titles
Figure 2. Static tilt achieved with ramped cushion and tension adjustable back canvas.
Figure 3. Static tilt achieved by adjusting the height of castors and rear wheel axle plate.
Tilt-in-space wheelchairs
DOI: 10.3109/17483107.2014.932021
3
Table 2. A summary of the inclusion and exclusion criteria. Inclusion Research studies 1980 to current Any age (participant) Any condition (participant) Available in English language Wheelchairs with mechanical or powered tilt-in-space that are utilised in everyday activities Field-based studies
Exclusion Pre-1980 Literature that is not research based Product or equipment focus Research focussed on static tilt Research focussed on pressure care alone Laboratory-based research
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Overview of the research
Figure 4. Tilt-in-space – which can be static, manually or power operated.
Table 1. A summary of the electronic search strategy undertaken. Electronic databases
Search terms
Search parameters
AMED Bandolier BNI Cochrane CINAHL DARE/NHSeed/HTA Google Scholar MEDLINE NHS Evidence OT Seeker PEDro PsychINFO Social Care Online
Wheelchair* AND (tilt* OR tilt-in-space OR var* position)
Publication years 1980 ! current Search title and abstract to refine literature sourced
and abstracts were checked for relevance using the inclusion and exclusion criteria outlined in Table 2. Research focused within a laboratory setting was excluded as the artificial environment of the laboratory would not reflect the study’s focus on everyday life experiences and occupations. All of the included studies were subjected to a quality assessment and data were extracted. Though ethical approval is not required for the completion of a literature review, the level of ethical reporting within the included papers was reviewed. Due to the heterogeneous nature of the included studies a narrative overview was used to analyse the data.
That only six studies could be included in this review, and all of them were small, exploratory studies (Table 3), shows that this is an under researched area particularly within the UK. Only one [9] study was conducted in the UK and the remaining five were from the USA. All of the participants were adult tilt-in-space wheelchair users with differing neurological diagnoses (Table 3). Three explored the use of tilt-in-space [1,9,12], one studied tilt-in-space and recline [10] with the remaining two evaluating tilt-in-space, recline and seat elevation [11,13]. All of the studies, except one [13], delineated the number of participants with either the tilt-in-space and/or recline and seat elevation functions (Table 3). Two of the studies [10,11] combined the functions tilt-in-space and recline into one statistic when reporting their findings. This made direct comparisons between the six studies difficult because they were too heterogeneous to combine, hence the use of a narrative overview for this research. The extent to which the studies explored the use of tilt-in-space wheelchairs in everyday life varied. The outcome measures included a range of digital monitoring systems and questionnaires. The digital monitoring systems, fitted to participants wheelchairs in four of the studies [1,11–13], were designed to scientifically measure and then analyse how frequently and for how long the participants utilised tilt-in-space, recline or seat elevation during the day (Table 3). Similarly, the data analysis in the fifth study [10] also produced data with a focus on frequency of use and the tilt-in-space and recline utilisation range. Although some detail was provided on the specific tasks, the tilt-in-space function was used for, this did not fully reflect its effect on activity and participation, even though this is important for understanding the impact of these wheelchairs on the everyday lives of the people who use them.
Narrative overview Facilitating activity and participation
Findings
Combined use of tilt-in-space and recline functions
In total, 997 hits were obtained following completion of the search strategy; after screening for duplicates the remaining 170 hits were relevance checked using the inclusion and exclusion criteria (Table 2). This process resulted in only six papers [1,9–13] being included for the quality assessment, data extraction (Table 3) and the development of the narrative overview. Papers excluded from the study involved those whose research focused on standard powered or manual wheelchair provision [14], static tilt and/or pressure care [15,16], posture [17] or wheelchair stability [18,19]. Following the convention of qualitative report writing the narrative overview is reported and discussed concurrently.
One study [10], identified an excellent level of participant satisfaction with several commenting that the opportunity to adjust seating orientation enabled them to complete their daily activities and maintain functional independence. In this study [10], 97.5% of the participants were found to utilise their repositioning systems daily. Others [11,13] reported the daily use of the tilt-in-space and recline functions, with tiltin-space used more frequently than recline [13]. While some participants significantly orientated themselves into a tilted position compared to the time spent in an upright position [11]. However, this study [11] also reports that its participants did not utilise the recline or seat elevation functions more than
Dewey et al. [9]
Lacoste et al. [10]
Citation
Focus
Aim: To explore and compare the experience of tilt-in-space wheelchair use and conventional wheelchair use in severely disabled clients with multiple sclerosis and significant spasticity.
Tilt-in-space versus conventional wheelchairs
Aim: To determine the use of specific types of repositioning systems, the frequency and range of use and global satisfaction level
Powered tilt and recline systems
Table 3. Data extraction table.
Phenomenology
Exploratory evaluation (Pilot study)
Research design
Diagnosis Multiple sclerosis
Age mean 55.5 years (range 35–71)
Yes
Yes
Hospital anxiety and depression scale and short orientation memory test (to assess mental state)
After the interview: Modified Barthel index (to assess met criteria to be included in study)
In-depth interviews, with guided interview schedule, in their home Carers present in n¼17 interviews
Participants were assessed in their home by an occupational therapy student
The important reasons for using the powered wheelchair were also ranked
Questionnaire assessed each item for Frequency of use Range of tilt Range of recline, and Satisfaction levels
A 25-item questionnaire developed using a literature review and two focus groups –[one with service users (n ¼ 5) and one with professionals (n ¼ 4)]. No reliability or validity testing
Data collection (including outcome measure)
(continued )
Benefits of tilt-in-space are comfort, improved postural support, enhanced seating stability, relief of pressure, rest out of bed for prolonged periods Difficulties tilt-in-space wheelchairs are bulky and lack manoeuvrability
Short orientation memory test (n ¼ 19) Mean score 22.3 (range 10–28)
Hospital anxiety and depression scale (n ¼ 19) Mean score 5.6 (range 0–16)
Modified Barthel index Mean score 4.6 (range 0–17)
Wheelchair Tilt-in-space (n ¼ 7) manual (n ¼ 2) powered (n ¼ 5) Conventional (n ¼ 16)
Important reasons for use Increase comfort, rest, reduced discomfort, bladder draining
Satisfaction levels 99% satisfaction rate
Range of tilt/recline Range of amplitudes used
Frequency of use All use. 97.5% use everyday
Risk of type II error
Wheelchair Tilt-in-space (n ¼ 26) Recline (n ¼ 10) Both (n ¼ 4)
Results
J. Harrand & K. Bannigan
Men (n ¼ 10) and women (n ¼ 13)
Response rate ¼ 88% (Three declined n reasons provided)
Diagnosis Neuromuscular disease (n ¼ 11) MS (n ¼ 17) Spinal cord injury (n ¼ 6) Other (not stated) (n ¼ 6) Convenience sampling of adults with multiple sclerosis and spasticity who were full time wheelchair users recruited through three wheelchair services. N ¼ 23
Age mean 46 years (range 21–69)
Men (n ¼ 32) and women (n ¼ 8)
Response rate ¼ 66.7%
N ¼ 40
Adults who owned a powered wheelchair with tilt-in-space and/or recline for at least one year who were recruited randomly from two rehabilitation centres in Montreal
Sample
Ethical approval secured
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4 Disabil Rehabil Assist Technol, Early Online: 1–10
Sonenblum et al. [12]
Ding et al. [11]
Citation
Aim: To describe the use of the power tilt systems in everyday life
Powered tilt-in-space
Aim: To examine the use of powered seating function including tilt-in-space, backrest recline, and seat elevation of wheelchair users during their typical daily activities
Tilt-in-space, recline and seat elevation
Focus
Descriptive study
Descriptive study
Research design
Age 22–69 years
Men (n ¼ 11) and women (n ¼ 5)
Convenience sample of adults who use tilt-in-space wheelchairs only N ¼ 16 Diagnosis Spinal cord injury (n ¼ 10) Cerebral palsy, cerebral vascular accident, muscular dystrophy, juvenile parkinsonism (no figures) Injured/diagnosed less than year (n ¼ 3); range was 2–59 years (median ¼ 6 years)
Diagnosis Muscular dystrophy (n ¼ 1) Spinal cord injury (n ¼ 4) Cerebral palsy (n ¼ 3) Multiple sclerosis (n ¼ 3)
Age mean 44.4 ± 14.5 years
Men (n ¼ 6) and women (n ¼ 5)
Response rate ¼ 92% (one response not reliable)
N ¼ 11
Convenience sample of adults who used a powered wheelchair independently referred by Human Engineering Research Laboratories wheelchair user registry or through a rehabilitation centre
Sample
Yes
Yes
Ethical approval secured
Wheelchair activity monitoring instrument (WhAMI)
Self-reporting questionnaire – little information given
End of study completed a selfreport questionnaire; no details about the tool
Used for two weeks
Seating function data logger (SFDL) developed for study which was mounted on wheelchair without modification and did not interfere with activities of daily living
Data collection (including outcome measure)
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(continued )
Median was 3.1 (±SD 4.3 ¼ /3.9) tilts per hour of wheelchair occupancy
Typical position Variety including typically sat at small tilt (0–14 ) and medium tilt (15–29 ) but few went past 45
Wheelchair occupancy 11 h (range 5–16.6) per day
Risk of type II error
Reasons for use ¼ reach higher levels, shop, sit at the bar, socialise, eat, read the calendar on the fridge, reach elevator buttons Wheelchair Only tilt-in-space included (recline excluded)
Correlation between selfreported and actual use not significant
Occupied wheelchair for 11.8 ± 3.4 h per day Transferred in and out 5.0 ± 5.3 times per day Accessed tilt-in-space 19 ± 4 times per day Stayed in tilt/recline 39.3% ± 36.5% of their time each day Changed positions every 53.6 ± 47 min
Wheelchair Tilt-in-space (N ¼ 11) Recline (n ¼ 9) Elevation (n ¼ 9)
Results
DOI: 10.3109/17483107.2014.932021
Tilt-in-space wheelchairs 5
Aim: To determine the features most frequently selected in a power wheelchair, level of satisfaction with the selections, and frequency of use
Power wheelchair; tilt-in-space, recline, seat elevation
To explore the use of PAMS to assess health, activity and participation with use of tilt-inspace wheelchairs.
Tilt-in-space
Focus
Retrospective survey
Pre-test–post-test study
Men (n ¼ 27) and women (n ¼ 18)
Response rate ¼ 71% (n ¼ 32)
Convenience sample (N ¼ 45) of adults with Amyotrophic Lateral Sclerosis/ Motor Neurone Disease who were current patients and powered wheelchair users
Diagnosis Cerebral Palsy Dystonia Muscular dystrophy Multiple sclerosis Spinal Cord Injury
Age range 30–60 years.
Men (n ¼ 1) and women (n ¼ 4)
Response rate ¼ 71% (n ¼ 5)
N¼7
Convenience sample of adults who have been issued with a powered tilt-in-space wheelchair.
Sample
Sought ethics approval – not required
Outcome measures conducted at:
Yes
Scores from the Amyotrophic Lateral Sclerosis Functional Rating Scale-Revised (ALSFRS-R) were collected
Developed by author (no details provided)
Semi structured, prompted recall interview Postal questionnaire 31-items
Community Participation and Perceived Receptivity Scale (self-reported)
Three months SF-8 (self-reported)
Use of chair Participatory and activity measurement system (PAMS) – Multipurpose data logger designed for the study GPS
Community Participation and Perceived Receptivity Scale (self-reported)
Baseline SF-8 (self-reported)
Consent and basic health questionnaire
Data collection (including outcome measure)
Ethical approval secured
(continued )
Level of satisfaction 88% were satisfied with their chair
Features most liked Leg rest, cushion, headrest
Wheelchair Tilt-in-space, recline, seat elevation but does not state numbers of participant using each type
Community destinations visited 3–29 over two weeks but little difference between pre–post test.
Changed positions – the frequency they did this varied.
Distances increased (n ¼ 3)
All used tilt system daily
SF-8 (self-reported) All showed improvements Physical and mental health (n ¼ 3) Only physical or mental health (n ¼ 2)
Self-reported reasons for use comfort / discomfort/pain rest / relaxation Wheelchair Powered tilt-in-space
Tilt frequency Few performed pressure relieving tilts Median ¼ 0.13 per hour.
Results
J. Harrand & K. Bannigan
Ward et al. [13]
Harris et al. [1]
Citation
Research design
Table 3. Continued
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6 Disabil Rehabil Assist Technol, Early Online: 1–10
Tilt-in-space wheelchairs
Focus Citation
Diagnosis Amyotrophic lateral sclerosis/ motor neurone disease
Age mean 57.9 years (range 27–85)
No difference for tilt, recline and power elevating leg rests
Frequency of use Increased use of seat elevator and attendant control
81% thought the chair was good value for money
Data collection (including outcome measure) Sample
Ethical approval secured Research design
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Results
DOI: 10.3109/17483107.2014.932021
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the tilt-in-space though significant differences were found in relation to the most frequently utilised tilt and recline angles available. Use of tilt-in-space function Three studies reported the daily use of the tilt-in-space function [1,11,12] with smaller amplitudes of tilt selected more frequently than the medium, large or extreme tilts available; however, no significant differences in tilt-in-space use was found over time [12,13]. Two studies [10,12] reported participants achieving some functional independence, with one of these studies specifically referring to the facilitation of transfers, personal hygiene, access under tables and eating [10]. However, it is difficult to draw conclusions because the first study [10] combined the use of tiltin-space with recline, whereas the wheelchairs in the second study [12] are fitted with the tilt-in-space function only. Similarly, the ability to draw conclusions is difficult in relation to the studies which report on bladder and bowel movements [9,10]. The participants in the first study [9] with tilt-in-space wheelchairs reported the ability to use tilt assisted with their bladder drainage, whereas the participants in the second study [10] with both the tilt-in-space and recline functions reported utilisation of the recline more than the tilt-in-space function to achieve bladder drainage and use of the tilt-in-space function eased bowel movement. Where the distance travelled by participants within the local community was assessed, following provision of a tilt-in-space wheelchair, it was found that three of the five participants did increase their travel distance [1]. One of the participants within this study whose travel distance declined was attributed to seasonal temperature changes. It was reported that despite community and activity levels not being significantly affected by tilt-in-space, there did appear to be improvements in perceptions of physical and mental health [1]. Compared to a study which took place in the USA [1], the UK study [9] found the ability to complete activities within home, such as in the kitchen and with accessing local transport links and the community, was hampered by the size, weight and manoeuvrability of tilt-in-space wheelchairs. Difficulties with access to the home and community environments can be accommodated, up to a point, by mid-wheel drive powered wheelchairs which have a greater capacity for turning within its own space [13]. However, the provision of these wheelchairs, via the NHS in the UK, is dependent on local guidelines and provision criteria and so are not necessarily universally available. Two of the studies [11,12] found that despite the frequent use of the tilt-in-space function, which can be used to facilitate the recommended angles of pressure relieving tilt, the participants involved were not following the USA repositioning or pressure care guidelines. This suggested there is a need for better training and awareness [12]. Interestingly, the participants in the UK study [9], reported that the provision of a pressure cushion would protect them from the development of pressure wounds; only one participant demonstrated knowledge of the potential risks involved of remaining in a static position without completing some form of pressure relief. One study [9] made particular reference to the devastating impact the development of a pressure wound can have in relation to the ability to participate in activities and subsequent effect on quality of life. Individuals who are unable to reposition themselves due to poor core stability, functional ability and/or have altered sensation are at risk from developing a number of postural deformities, for example: postural kyphosis, posterior pelvic tilt, chin poke, neck hyperflexion or extension, scoliosis, obliquity and rotation of the
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spine and pelvis [5,20]. The effect of postural changes can lead to increased pressure loading resulting in the development of pressure ulcers with the combined effect of increased pain and discomfort, physiological complications and loss of functional independence [5]. Of the six studies included, two found that participants utilised the tilt-in-space feature to reduce the effects of sliding [9,10], whereas some participants utilised the tilt-inspace and/or the recline features to improve stability and balance [10]. Overall, the positive impact of tilt-in-space, and/or recline, experienced by the participants within the six studies includes: breathing [10], napping, resting or relaxing [9,10,13], comfort [1,9–11,13], the opportunity to spend greater amounts of time outoff bed [9], pain management [1,10,12], pressure relief tilts [1,10– 12] and a decrease in spasms [9].
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Occupational engagement and quality of life Although all six articles reported the intention of exploring the use of tilt-in-space, recline and/or seat elevation in relation to everyday life, the research did not focus on occupational engagement and the impact of this on the participants. For example, where the number of community destinations was explored and found to have increased [1], the research does not appear to further examine what if any specific activities were then accessed and what the impact or meaning of this was to the individual. For instance if, following provision of a wheelchair with the tilt-in-space and/or recline functions, pain was reduced and comfort improved, the ability to tolerate remaining at a destination may have increased so enabling the person using the wheelchair to participate in desired activities for extended time periods with the overall effect of enhancing occupational engagement. It is suggested that clinical perceptions of importance may differ significantly between health care professionals and the people they work with [9]. When considering community access (a shop), the clinician or researcher may consider that occupational engagement has been achieved, whereas from the perspective of the patient occupational engagement is enhanced by the activity itself (shopping). Of the six studies included in this review, five made a direct reference to the term quality of life [1,9,10,12,13]. One study concluded that quality of life could be an outcome measured via self-reporting tools [1]. Another highlighted that quality of life is one of the important elements to consider when assessing the mobility needs of individuals [13]. A small sample size and the diagnosis of participants (deteriorating neurological) were the reasons provided by one study for not including this issue within their study [9]. Recognising that quality of life is not necessarily directly included within a medical needs assessment, one study suggested that quality of life could be measured as part of participation and activity outcomes generally [12], whereas the fifth study [10] only referred to quality of life within their introduction and literature review. Although not all of the studies reported their findings using comparable data, and frequently combined the use of the differing functions [10,11,13], the implication overall is that the use of tiltin-space and/or recline may have therapeutic benefits. The studies do not provide clear indications as to whether the participants were able to participate in a greater number and variety of activities over extended periods of time, or, what the overall impact this may have had on occupational engagement or quality of life issues. The studies do not provide clear indications as to whether the participants were able to participate in a greater number of activities and/or whether for extended periods of time, what these activities were and the overall impact this may have had on occupational engagement or quality of life issues.
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Quality assessment A number of issues have arisen from this research related to validity. All six were small exploratory studies (Table 3), with only one study [11] making reference to the use of a power analysis to determine sample size. Across the six studies a wide range of data collection methods were used including differing self-reported questionnaires and digital monitoring systems. With the use of retrospective questionnaires comes the potential for recall bias, which was acknowledged in one of the studies [13]. Some of the included studies collected data over short time span, which could have reflected poorly upon the usage patterns of wheelchairs [1,10–12]. The methods utilised by all six of the studies were poorly described affecting the ease of replication and three of the studies did not always distinguish between those participants using tilt-in-space and/or recline wheelchairs [10,11,13]; an issue which contributes to the heterogeneity of this review. Ethical approval was secured by five of the studies [1,9–12] with the sixth [13] reporting that the review board they approached stated ethical and informed consent was not required due to the nature of their study. Flaws were identified in the limitations of four of the studies, particularly with sampling and recruitment [1,10,11,13]; challenges which, in part, contributed to the small sample sizes. For example, one study [10] had intended to recruit 30 participants to each group with either the tilt-in-space or recline functions; the number of participants who consented to participate totalled 40 with combined or unevenly spread functions. The challenges raised here suggest that sampling and recruitment is an issue requiring attention when designing future studies. It was suggested that the limits set to measure function usage, via the digital monitoring systems, may have been less than optimal [11]. Two of the studies raised the issue of sampling bias in relation to participant diagnosis [10,12], with one suggesting that the variance in conditions may have biased their findings [10]. Although the quality assessment raises questions of the overall rigour of the included studies, collectively the studies’ findings raise several valid points for discussion and future consideration. Examples include: the benefits of combining subjective (questionnaires, interviews) and objective (digital monitoring systems) data collection methods [1], the importance of gathering information directly from the patient’s (participants) perspectives [13]. Perhaps service users should be involved in the design of future studies. Although this review has failed to firmly establish or refute the clinical or therapeutic benefits of tilt-inspace (and/or other functions such as recline) wheelchairs, the conclusions of the studies reviewed do indicate that with robust research methods the benefits are more likely to outweigh the disadvantages. Implications for practice The above quality assessment demonstrates that the findings of the included studies cannot be translated into practice and should be interpreted cautiously. The findings do suggest that tilt-inspace outcomes should be researched further. For example, the findings from one study [10] suggests the tilt-in-space and recline functions were important to their participants because without them independence would have been affected. However, this would need to be tested in more detail to determine whether this statement stands up to the scrutiny of the larger population of wheelchair users. Given the problems that can arise with postural deformity and skin integrity through poor positioning, and by not following repositioning guidance, practitioners should consider whether the levels of training and education currently provided are appropriate or adequate.
Tilt-in-space wheelchairs
DOI: 10.3109/17483107.2014.932021
At present, the question of whether tilt-in-space wheelchairs benefit those who use them remains unanswered. It could be suggested that during the assessment, training and hand-over phases of tilt-in-space wheelchair provision, greater emphasis is placed on how and why these functions may assist individuals to complete various tasks and activities, including daily living, posture and pressure care. A uniform and robust method of measuring outcomes and reviewing provision in the long term is a first step in the process of developing the evidence base for their effectiveness in relation to occupational performance, engagement and quality of life. Opportunities for integrated multi-professional working should be explored to ensure, amongst other things, the consistency of advice given and the joint funding and pooling of budgets ensures that increasingly limited resources are used judiciously.
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Implications for future research This review has highlighted a number of issues for those planning to conduct future research into tilt-in-space wheelchairs to consider. Suggestions include: larger studies with broader recruitment, for example, the inclusion of paediatric patients, a wider range of diagnoses across both adult and paediatric participants, and involving a number of wheelchair services to ensure sufficiently powered studies. The functions tilt-in-space, recline and seat elevation should be researched within the same studies but must be approached in such a way that direct comparisons can be drawn. The focus of the research should be relevant and clearly represent both the interests of the users and the service outcomes. Allowing sufficient time for data collection to reflect usage patterns will be a key factor in the planning process. Appropriate, valid and reliable instrumentation including occupational performance measures and digital monitoring systems should be used to capture data. Given the urgent need for research in this field within the UK, perhaps key stakeholders such as the Posture and Mobility Group, the National Wheelchair Managers Forum and the Regional Wheelchair Therapists and Rehabilitation Engineer Specialist Interest Groups could collectively design and conduct a large scale study that will generate sufficient power to inform policyholders and commissioning bodies. At the very least, agreeing outcomes of interest would ensure homogeneity between any future studies. A multi-professional research design would potentially capture and reflect the views of occupational therapists, physiotherapists, rehabilitation engineers, nurses, and speech and language therapists which, alongside those of the patients involved, would provide a rich pool of data for analysis. As the core philosophy of occupational therapy is the promotion of independence through activity and occupation, it would be in the profession’s interest to be at the forefront of such an extensive research project. It is suggested that the most rigorous form of research, a Randomised Control Trial to reduce confounding factors within the research process and protocol are minimised [21–23], is used as the study design. However, the use of a randomised control or clinical trial to determine the effectiveness of mobility devices may be difficult [16] unless a pragmatic approach is used; for example, using a waiting list control group. Limitations of the review Although a wide-ranging search strategy was implemented, resource constraints meant it was not possible to search for grey literature or non-English language studies, which may have contributed to this review. The relevance checking and thematic analysis were completed by a single researcher with subject
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expertise following inclusion and exclusion criteria which were developed a priori. The numbers involved suggest fatigue is unlikely to have been an issue when relevance checking. The second author checked data extraction of the included papers and so was able to assess that the thematic analysis reflected the data rather than the researcher’s assumptions.
Conclusion This review has identified a lack of high quality evidence about the benefits of wheelchairs with the tilt-in-space function and is therefore unable to make any specific recommendations for best practice other than to suggest the potential need for improved training and education. The conclusions of the included studies implied that there are potential benefits of tilt-in-space wheelchairs but that further research is required to support their findings. Although the lack of evidence is not evidence of no effect, given the expense associated with providing wheelchairs with the additional functions of tilt-in-space and/or recline and seat elevation, the ability to continue justifying limited resources to the provision of higher specification wheelchairs is questionable. The need for further research of a sufficient quality to guide clinical practice is therefore indicated.
Declaration of interest The authors report no conflicts of interest. The authors alone are responsible for the content and writing of this article. This study was completed as part of the requirement for the degree of MSc in Professional Health and Social Care Studies at the Facility of Health and Life Sciences, York St John University in conjunction with the Research Centre for Occupation and Mental Health.
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