Low, Sheryl A. PT, DPT, DSc, MPH, PCS; McCoy, Sarah Westcott PT, PhD; Beling, Janna PT, PhD; Adams, Janet PT, MS
Walkers are often prescribed for children to provide the support and assistance required for ambulation. Researchers have documented the benefits of posterior walkers over anterior walkers1,2 and the effects of partial unweighting during walking practice for children with cerebral palsy (CP) classified primarily at levels I to III of the Gross Motor Function Classification System (GMFCS).3–6 Children with more severe mobility restrictions (GMFCS levels III-IV) usually require more support for their trunk and pelvis than hand-held walkers can provide.7,8 Children with severe mobility restrictions are now being considered for various types of assistive mobility devices to allow some upright walking. For this project, the term support walker (SW) was used to describe any mobility devices used with children who need more support than a hand-held walker, including some manner of trunk, forearm, and/or pelvic support.
Since the 1990s, SWs have been used with increasing frequency in the school setting due in part to several factors including the development of the Mobility Opportunity Via Education curriculum for children with severe disabilities9–12 and an increasing focus on activity, participation, and fitness for children with severe multiple disabilities.13,14 Support walkers provide children with severe multiple disabilities frequent opportunities to practice functional motor skills in a task-oriented manner9–12,14 in the school setting. This equipment is usually shared among many children in the school setting; thus, it was designed to be adjustable for children of varying sizes and functional levels. To be functional for multiple children, the equipment needed to provide a range of support using removable attachments, be convenient to adjust, and easy for staff to place children in and take them out of the equipment. Support walkers were also designed to allow children access to their peers and to participate in activities in the school or home setting. Over time, many manufacturers have developed their own versions of SWs and currently there are many devices available for purchase. Most SWs consist of a metal or plastic frame with 4 wheels, a brake system, and are square or ring shaped to enclose the child's trunk while upright. Attachments may be added to the frame to maximize the child's positioning and optimize gait while in the SW and may include a seat, or pelvic sling, an abductor pommel, antiscissoring systems, forearm supports, trunk supports, suspended strapping to unweight the child, and handles or grab bars. Many systems are height and angle adjustable and some models are reversible allowing the child to use the SW either anteriorly or posteriorly. The castors or wheels can usually be locked in a sagittal plane or rotate all directions. Most SWs can be dismantled or folded for transport and are available in 3 basic sizes to fit children and adults of all ages.
Support walkers are considered assistive technology (AT) under the Individuals with Disabilities Education Act,15,16 and durable medical equipment under most insurance plans.17 The legal definition of AT and AT services under Individuals with Disabilities Education Act is shown in Table 1.
Parents and educators promote using SWs in the school setting and at home to assist in ambulation and general exercise for children with severe or profound multiple disabilities including writing functional educational goals specific to this type of assistive device.15,16 Initial recommendations for an SW might be made by the pediatric physical therapist (PPT) providing individual physical therapy to a child or by a member of the multidisciplinary team.15,16 This team includes the family, the physician, the occupational, physical, and/or speech therapist, the school nurse, the teacher, and any other allied health care professionals providing services for the child.15,16 According to Individuals with Disabilities Education Act,16 the Guide to Physical Therapist Practice,18 and current guidelines for clinical decision making for children with CP,19–22 the PPT has a unique role as part of the multidisciplinary team recommending the most appropriate SW to optimize upright mobility for a child with disabilities when providing the AT service.23
It is the role of the PPT to examine, assess, and make recommendations for the most appropriate AT to improve a child's functional mobility in all settings,24–27 to assess gait, posture, and alignment while using the SW,24–27 and to consider the child's self-determination and participation in daily activities.25 It is also the role of the PPT to consider the needs, wants, and capabilities of the family and classroom staff, including teaching safe and proper use of the SW.28
Not only must PPTs formulate clinical decisions in the contexts of their practice settings, they must also uphold the standard of evidence-based practice. According to Sackett et al,29 evidence-based practice is defined as the “integration of best research evidence with our clinical expertise and our patient's unique values and circumstances.” Recommendation and use of SWs by PPTs should be made in light of all of these factors, but only 1 published study examines SWs for children with CP.
A group of researchers developed the Supported Walker Ambulation Performance Scale (SWAPS). This scale is an outcome measure used to assess the gait of children with CP before they become independent walkers.30 The SWAPS evaluates 4 areas of locomotion: (1) degree of support, (2) posture, (3) quality of the steps, and (4) quantity of steps. These areas are scored using a 4-point Likert scale and weighted for a possible score of 100 for an independent ambulator. The same group of researchers also conducted a feasibility study, using the SWAPS to measure changes in locomotor status for nonindependent walkers using SWs and determined that the SWAPS was a sensitive tool for previously nonambulatory children but needed further research.31 Evidence is lacking to guide PPTs in the recommendation and use of SWs.
The purpose of this research was to begin documenting that SWs are being used by PPTs for children with disabilities. Within this article, we discuss the results of a national survey investigating the clinical decision making and use of SWs in the pediatric clinical setting and explore factors considered by PPTs when recommending the most appropriate SWs for children with disabilities.
An 8-page survey instrument was developed by the authors and reviewed for content validity and ease/accuracy of responding by 10 clinical experts in pediatric physical therapy (see the Appendix, Supplemental Digital Content 1, at http://links.lww.com/PPT/A26). Changes were made on the basis of the input of these therapists. The survey was designed to reflect current practices and clinical expertise related to the use of SWs and was approved by the appropriate Institutional Review Boards before sending the survey. The survey packet included a cover letter explaining the purpose of the survey, an operational definition of SWs, implied consent by response, and a postage-paid return envelope. The survey included 2 pages of demographic questions and 6 pages of questions about the recommendation and use of SWs including clinical decision making. Most of the survey question responses required either dichotomous (yes or no) or a Likert-type ratings using a scale from “strongly agree” to “strongly disagree.” Open-ended questions soliciting comments regarding the use of SWs in the clinical and school settings were also included.
The 8-page survey with a cover letter and postage-paid return envelope was mailed to 2500 randomly selected members of the Section on Pediatrics (SOP) of the American Physical Therapy Association (APTA) nationwide, representing 63% of the members. The survey was also announced electronically with a link to the survey Web site on the SOP list serve. There were 520 respondents by mail and 63 respondents through the Internet, with 195 returned by the post office. Of the surveys, only 450 received by mail were fully completed, whereas all 63 surveys received through the Internet were completed resulting in a total of 513 completed surveys for a response rate of 21%. Although this response rate is low, it does represent PPTs across all 50 states and Puerto Rico. Surveys were completed anonymously. Table 2 describes the 513 PPTs who fully completed the survey and the demographics of the caseloads they serve. The demographic characteristics of the respondents are similar and consistent with other surveys of PPTs about clinical decision making in the school setting,21,23 which would imply a representative sample of school-based PPTs. Most were women (95%), averaging 15 years as a physical therapist (PT), 12 years as a PPT, and worked as employees (60%) in a suburban (36%) and school setting (41%). Most were educated at the bachelor (50%) or master of physical therapy (42%) level and 26% had earned post–entry-level degrees. Fourteen percent were board certified in pediatrics by the American Board of Physical Therapy Specialties. Thirty-nine percent reported attending at least 2 continuing education courses a year and 35% reported attending at least 3 continuing education courses a year.
Descriptive statistics were calculated using Statistical Package for the Social Sciences (version 15, SPSS Inc, Chicago, IL).32 Frequencies were calculated for demographic information and questions about the use of SWs. For the purposes of statistical analysis, results of the Likert style questions were collapsed from 5 categories of strongly agree, agree, neutral, disagree, and strongly disagree into 3 categories of agree (strongly agree, and agree), neutral, and disagree (strongly disagree and disagree). The totals of responses for the 3 categories equal 100%, but each of the Likert questions was designed with a root statement allowing several responses to the same root question, so percentage totals could exceed 100% for a single root question, but each completing statement totals 100% for a number of respondents. For example, the root question for question 1 is “The support walker I recommend the most is:” and lists 10 options. Thus, a respondent could rate 2 walkers as strongly agree if they recommend both walkers.
Comments were solicited after 18 survey questions to seek more specific information on using SWs. Comments from all open-ended questions were coded and grouped into thematic groups for descriptive analysis. There were approximately 450 comments to specific questions, which clarified respondents' answers to questions 1 to 20 and 242 comments to the final open-ended question on the use of SWs. Narrative comments to final question were categorized by themes and ranked by a number of responses.
Respondents ranked the 9 most commonly used SWs in descending order as the Rifton Gait Trainer (78%; Rifton Products, Rifton, NY), Kaye PWB Suspension (70%; Kaye Products Inc, Hillsborough, NC), Litegait (35%; Mobility Research, Tempe, AZ), Pony (32%; Snug Seat Inc, Matthews, NC), Gator (22%; Sung Seat Inc, Matthews, NC), Croc (16%; Sung Seat Inc, Matthews, NC), Bronco (12%; Sung Seat Inc, Matthews, NC), Mulholland Walkabout (9%; Mullholland Positioning Systems Inc, Burley, ID), and Mae Walker (1%; Mae Walker, no longer manufactured). All results are listed in Table 3. The respondents reported that SWs are most often recommended for children with the diagnosis of spastic CP (88%), ataxic CP (67%), dyskinetic CP (55%), developmental delay (42%), spina bifida (42%), spinal cord injury (29%), and pediatric orthopedic disorders (28%).
Table 4 lists the impairments and physiologic factors considered in the selection of an SW ranked in descending order of agreement by respondents. Impairments considered in order of importance were weakness (92%), motor control (89%), poor balance (88%), posture (81%), endurance (81%), hypertonia (73%), gait pattern (72%), hypotonia (71%), cognitive status (69%), and range-of-motion deficits (66%). Physiologic factors considered in the selection of an SW ranked in order of importance were hip development (82%), respiratory status (81%), cardiovascular status (80%), bone density (80%), peripheral circulation (60%), pressure relief (59%), gastrointestinal function (37%), and renal function (25%).
The factors considered important in the selection of an SW are listed in Table 5. When asked to rank the most important criteria for the selection of a particular SW, 93% of the respondents ranked clinical assessment, followed by the time a child could spend in the SW (79%), current evidence (76%), funding by the agency (54%), the time to adjust the SW (47%), the agency's access to a particular type of SW (27%), and the vendor's supply of a particular SW (13%). Thirty-nine percent of respondents did not use vendor supply or agency's availability in their decision-making criteria.
In considering the family's concerns in the selection of an SW, 82% of respondents agreed that the parent's preference for a particular SW is the most important family consideration, followed by the family's ability to adjust or maintain the SW (77%), the child's preference (76%), and lastly the family's financial resources (56%). Ninety-two percent of respondents agreed that a child's activity level is more important than a child's age (64%) as a factor in the selection of an SW. The most common theme found in the responses to the open-ended questions at the end of each specific question (39 responses) was that the PPT recommendation for a particular SW depends on the child's individual needs, “clinical picture,” and family situation.
Table 6 outlines the most common practices in the use of SWs by PPTs. Support walkers were reported to be used posteriorly 65% of the time and anteriorly 53% of the time. Respondents reported that the accessories most used were trunk prompts (87%), forearm supports (78%), pelvic seat or sling (67%), and antiscissoring systems (61%). Time periods most commonly reported for trial use before purchase is 1 month (45%), 2 weeks (40%), 1 week (31%), and 1 day (16%). Pediatric physical therapists report that a minimum of 9 sessions was required to train the child in the use of an SW (50%), 6 to 8 sessions (48%), 3 to 5 sessions (43%), and 1 to 2 sessions (17%). The largest percentage of respondents reported that the optimal number of sessions required for the child to independently move the SW was 9 or more sessions (46%), followed by 6 to 8 sessions (43%), 3 to 5 (36%), 1 to 2 (14%), and other (14%).
The second and third most common thematic responses to the open-ended questions were that SWs are used to encourage mobility and exercise (27 responses) and are used because they are versatile and can adapt or grow with the child (17 comments). Activities that facilitated functional gains included interaction with peers (94%), participation in school (91%), performing activities of daily living at school (87%), participation in the community (84%), performing activities of daily living at home (83%), and participation in play (77%). The setting that a child spends the most time in an SW is reported as the classroom (74%), followed by the home (66%), the physical therapy clinic (47%), and the community (33%). Amount of time per week reported by PPTs for a child to practice in the SW was 5 to less than 10 hours per week (63%), or less than 5 hours per week (42%), 10 to less than 15 hours per week (36%), 15 to less than 20 hours per week (19%), and greater than 20 hours per week (19%). The overall duration reported for the use of an SW was less than 6 months (36%), 6 months to 1 year (20%), greater than 2 years (15%), and 1 to 2 years (12%). Furthermore, respondents reported the percentage of children who graduate from an SW to a hand-held walker as 31% to 50% (64%), followed by 10% to 30% (58%), greater than 70% (47%), 51% to 70% (37%), and less than 10% (30%). Most clinicians (60%) reassess the use of the SW every PT visit, whereas 25% reassess daily, 13% biannually, 10% weekly, and 4% monthly.
Respondents indicated the child's GMFCS level (84%), with other factors such as motivation to walk (77%), and cognitive level (74%) as the most crucial factors for a child's success in using an SW. Other factors important to successful use by children with disabilities were ranked in descending order as family support (50%), positioning in SW (43%), unweighting (37%), therapist training (30%), and practice in the SW (4%).
Five hundred thirteen respondents completed and returned the 8-page survey, which demonstrates that a proportion of PPTs are recommending and prescribing SWs in their clinical practice and are interested in this information. The low overall response rate (21%) may have been influenced by PPTs who were not working with caseloads appropriate for SWs deciding not to return the survey, even though there was a place to indicate this and return the survey. At the time of the mailing, there was no school special interest group of the SOP to clearly identify those members of the section working in the school setting. The survey's length may have also affected the response rate. An 8-page survey may have required more time than a busy PPT has time to complete. It is difficult to determine why the lower response rate than 3 other recent surveys of PPTs with response rates of 77%, 61%, and 57%33–35 but higher than 2 recent surveys at 9.6% and 13%.36,37 The random list of therapists was not reviewed for practice area before mailing of the survey and the list was not reviewed to eliminate section members who were not currently practicing. These factors could have influenced the results.
Considerations in Clinical Decision Making
Quantitative and qualitative responses indicate that PPTs believe they are basing their recommendations for the type and use of an SW primarily on a child's individual physical therapy assessment and family/school context. The most common thematic response to the comment section was that “it depends on the child's clinical picture.” This would seem to indicate that PPTs consider many factors unique to each particular child to determine which SW to use and how it is used for that child in practice.
What does “clinical picture” mean and include? Current models for clinical decision making in pediatrics19–22 follow recommendations from the Guide to Physical Therapist Practice,18 and the World Health Organization's International Classification of Functioning, Disability, and Health.27 Thus, the “clinical picture” would include an examination of a child's impairments and physiologic functioning, an evaluation of the child's cognitive status and motivation, the child's age and diagnosis, the unique needs, and ability of the family and their child's ability to participate in age-related activities.25,26,28
Respondents strongly agree that SWs were selected with consideration for the impairments and physiologic factors of the child consistent with the Guide to Physical Therapist Practice and International Classification of Functioning, Disability, and Health models of clinical practice. Strength, motor control, balance, and endurance are all required for good postural control and independent gait.38 Selection of SWs to address these impairments as a pregait activity for children with disabilities is supported by recent studies focusing on increased strength as an intervention to improve gait and postural control38–40 as well as using the motor activity around a purposeful task to improve selective motor control.14,39
The respondents' ranking of the use of SWs to improve hip development, respiratory and cardiovascular function, and bone density over other physiologic factors such as peripheral circulation, pressure relief, gastrointestinal function, and renal function demonstrates a current belief by therapists that weight-bearing can improve these physiologic factors despite the lack of research in this area.41
Decreased bone mineral density (BMD) has been documented in children with CP and severe disabilities,41–43 and in 1992, Stuberg44 made the first recommendations on weight-bearing programs for children with disabilities. On the basis of Stuberg's recommendations, nonambulatory children should be weight-bearing at least 60 minutes per session 4 or 5 times a week to retard bone loss and should begin weight-bearing programs as early as 12 to 16 months of age.44 Stuberg also cites intermittent loading during weight-bearing as more effective in animal studies than a static weight-bearing program.44
A recent meta-analysis by Pin41 examined 10 studies investigating the effects of static weight-bearing exercises on BMD and reductions in spasticity. Pin concluded that although there is limited but good evidence for improvements in BMD of the spine and femur after static weight-bearing exercises, no research evidence is available to support using these exercises to improve hip dysplasia or bowel or urinary functions and she cautions clinicians on making such recommendations.41 Other studies have investigated dynamic weight-bearing and its relationship to BMD and found improvements in BMD after using a dynamic stander and recommended ambulation of distances greater than 100 ft to affect physiologic function of bone development and remodeling.45,46
Other physiologic functions were ranked high, but we can only speculate about why they were ranked so high. A possible explanation for the high ranking of cardiovascular and respiratory function may be related to the documented evidence across all population and age groups on improvements in cardiovascular and respiratory function secondary to gait and exercise.47 This may be based on the assumption that an SW would not be used as a static standing device but as an ambulation device and the consequent effect of walking on cardiovascular and respiratory fitness in the children. There is emerging research on the positive effects of fitness for the respiratory and cardiovascular health of children with disabilities, but there is no research on respiratory or cardiovascular fitness for children with severe disability.47
The second most important reason in the selection of an SW was the time a child can spend in the SW. This is also consistent with models of clinical decision making focusing on improving a child's participation in age-related activities48 and makes clinical sense because the school or family circumstances should support practice time for a child using the SW in their daily activities. It also emphasizes the role of the PPT not only to assess, order, fit the SW, and train the family and caretakers, but also to assist in implementing activity plans to ensure that the equipment is used as much as possible.23
Current evidence was ranked third in selecting an SW after clinical assessment and the time a child can spend in the SW. It appears that SWs are primarily recommended to improve gait and mobility, but there is no evidence on how SWs can improve the quality of gait or how to standardize which SW is recommended for which gait dysfunction or how to use the SW as a standard treatment for improving mobility outcomes. Although PPTs believe that they are using current evidence in the selection and use of SWs, there is no direct evidence documenting outcomes to guide them. Thus, it is difficult to determine whether PPTs are making the best decisions in their selection and use of SWs.
Support Walker Recommendations
The two most commonly recommended SWs are the Rifton Pacer Gait Trainer (78%) and the Kaye Support Walking System (70%) and the third most highly recommended SW only suggested by 35% of the sample. This may reflect the use of the Rifton Pacer Gait Trainer as part of the Mobility Opportunity Via Education program, which would be purchased by schools using this curriculum and the common use of the Kaye hand-held walker for children with spastic diplegia and the ability to convert the Kaye walker to an SW system. Both the Pacer model and the Kaye system have more flexibility for adjusting the amount of support as children progress, and all extra supports can be removed to allow them to be used as hand-held walkers. The majority of respondents agreed that a third to a half of children using SWs progress to using hand-held walkers, but there is currently no research demonstrating why these 2 brands of SWs are ranked as the most commonly recommended and used.
Most respondents agreed that they used trunk and forearm supports most often. This practice would partially unweight children allowing improved selective motor control during a gait activity consistent with current theories of motor control.3–6,35 Respondents were nearly equally divided in using the SW anteriorly or posteriorly. The Rifton model is cited as the most commonly used and is also the most easily reversible. Children can be placed in the walker either direction from the front or back, but determining why an SW is used anteriorly or posteriorly in children with severe motor disabilities remains unclear at this time.
Support Walker Intervention Programs
Respondents reassessed the use of the SW every PT session reporting that at least 9 or more sessions were required for optimal use by the child. Again, it is notable that more than half of respondents disagreed with the statement that “no sessions” are needed to train the child. Respondents clearly feel that physical therapy is essential for follow-up once the SW is purchased. Support walkers are used primarily in the classroom 5 to 9 hours per week, consistent with Stuberg's recommendations for weight-bearing 45 to 60 minutes per day 4 to 5 times per week.44 Using SWs during activities focusing on interaction with peers is believed to encourage participation. Overall durations reported for children to use an SW are less than 6 months and as stated earlier, a third to a half of children are reported to progress to ambulating with a hand-held walker. This would appear to indicate that in clinical practice SWs are used to progress children from a dependent gait status to a more independent gait status.
Factors for Success
What factors do PPTs believe contribute the most to a child's success with an SW? The child's GMFCS level was ranked the highest, with motivation and cognition before family support, followed by positioning, unweighting, or therapist training and practice. Although the GMFCS level has been shown to correlate with motor performance over time,7 it has been validated only for children with CP; so it is notable that PPTs rank it as the most important when SWs are used with all types of diagnosis. Motivation and cognition have also been shown by researchers as key factors in models for predicting school participation of children with disabilities.48
Respondents cite parent's preference and the family's ability to adjust or maintain the SW as the 2 most important family considerations in selection of an SW. The family's role in the use of the SW is crucial to the child's success and is also consistent with best practice and clinical guidelines in recommending durable medical equipment and AT for children with disabilities.22,23,28
Another factor that respondents ranked important as a selection criterion for using an SW is a trial period before purchase. This would also allow clinicians to ensure that their recommendations include the child's unique clinical picture, the family's needs and home environment, the school setting, and the recommendations of the child's educational and medical team before purchase.
The validity of this survey is affected by several threats. An overall low return rate and inclusion of only APTA SOP members in the sample do not allow one to assume that the sample was representative of all PPTs practicing in the United States. The survey format and Likert-style questions may have skewed or limited the information gathered about SWs and because the survey was self-administered, it is difficult to determine the objectivity of the respondents or how subjective experiences may have affected individual responses.
This survey has highlighted reasons why PPTs believe that they are recommending SWs and begins to document how they are used, but it also raises many questions on whether PPTs are making the best decisions for children with various disabilities when there is no direct evidence to guide them. Support walkers are being recommended and used to improve mobility for children with disabilities while participating at school and home. Studies are needed that investigate the effect of SWs on gait, mobility, activities of daily living, and participation using focused, reliable, and valid assessment tools and outcome measures.