AT Research

If Passive Standing Is Good, Is Dynamic Even Better?

Funding is casting ever-longer shadows over assistive technology these days…and in at least one case, inspired research that is showing encouraging results in some of complex rehab’s youngest clients.

From their collaborative work in the rehabilitation technology department at Children’s Specialized Hospital and the biomedical engineering department at New Jersey Institute of Technology, Megan Damcott, MS, and Sheila Blochlinger, PT, ATP, knew pediatric patients who used standing frames. They were also concerned over a shift in funding trends.

“What made us start out to do this research was we were getting more and more denials from insurance companies for standers and gait trainers,” Blochlinger says. “That was really why we came up with the idea to look at it.”

Getting Started

Their preliminary work included reviewing existing information on the subject of standing. “A lot of studies that were done on passive standing include maybe one or two children,” Damcott says, “so the goal was to capitalize on the larger population we have available to us.” Children’s Specialized in Mountainside, N.J., Blochlinger notes, is the largest freestanding pediatric rehab hospital in the United States, and is also “affiliated with a school, so that school has children that come every day and participate in a standing program. We were able to recruit subjects in the school, then we expanded to another school, where I had worked previously, to get other subjects.”

Examining the available information on standing also led to a major decision about the direction of their own research, Damcott adds: “As we were doing the literature review, that’s when we determined that dynamic standing might be more beneficial. We’re investigating passive and dynamic now.”

For this research, Blochlinger and Damcott designed a dynamic stander that, in addition to standing the child up, would also provide motion to mimic the reciprocal movements of walking.

Damcott says, “For the passive stander, you’re standing on one continuous footplate. So the only reciprocating forces you get are if they’re shifting their weight as they’re standing. During passive standing, they shift about 40 to 60 percent of their body weight.”

The dynamic stander features two separate footplates, “and they go up and down,” Damcott says, to simulate a walking beat. “Their body weight shift right now is about 25-75 percent. We started off conservatively, as these children are already at risk to fracture.”

She explains, “Right now, we’re looking at bone mineral density, primarily of the distal femur, because that’s where, in this population, the majority of fractures occur. We’re looking at the impact between dynamic and passive standing, and we’re also recruiting non-weightbearing children so we can compare all three.”

The project, funded by the National Institute on Disability and Rehabilitation research, is in its third iteration, Blochlinger says. They first conducted a 13-week pilot study “just to make sure that what we had (the dynamic stander) was working and we could use it in a school setting, in a clinical environment,” she notes. That pilot study included two children: One used a passive stander, one the dynamic stander.

That was followed by a six-month study that finished up in October 2009. At the end of that study, there were 16 children participating, with half doing passive standing, the other half doing dynamic standing.

The children range in age from 2 to 9 years old, and most have been diagnosed with cerebral palsy, though Blochlinger notes, “We didn’t limit the study to diagnoses.”

Clinical Discoveries, Family Observations

Blochlinger and Damcott have started another six-month study featuring the same basic group of children. Several children won’t be participating this time, for reasons unrelated to the first study — for instance, one child moved out of the area, while another passed away. Currently, five children are doing passive standing, while five more are using the dynamic stander.

Both six-month studies were set up to be as unobtrusive as possible: The participating children were already in a standing program, so the ones in the passive portion of the study continued and will continue to use their standing frames. Children in the dynamic portion of the study began using the dynamic stander instead during the first study and will continue in the dynamic standers in the second study.

“We wanted to keep everything the same,” Blochlinger says. The children in the study are non-verbal, so they’re not able to tell Blochlinger and Damcott, for instance, whether they like the dynamic stander better than the passive stander. But adults familiar with the children have noticed changes in behavior from the kids who are dynamically standing.

“Teachers and aides in the long-term-care pilot study and also over at the school actually saw that children that are more sensitive to stimulation seem to be calmer and more alert in the dynamic stander,” Damcott says. She adds, “So far, it looks like the dynamic stander does increase the bone mineral density, even with all the other compounding factors that we didn’t control for. And passive seems to maintain the bone density.”

Caregivers also mentioned that kids in the dynamic study had improvements in digestion, among other functions.

“We’ve seen that kids that have higher muscle tone are more relaxed,” Blochlinger says. “Parents are telling us they’re easier to manage at home. Some of the kids who were beginning to take some steps are taking a few more now. They’re bearing more weight now through their legs. It’s exciting.”

Potential Impacts on Funding

During the first six-month study, Damcott says, the children’s bone densities were measured at zero, three and six months.

“Between zero and three months, we didn’t really see a significant difference, but then between the zero and six months, we did,” she notes. “Maybe it does take a little longer for the onset of the differences to appear.” She and Blochlinger would therefore like to investigate whether kids’ bone density scores would improve even more after one year in the program.

The answer to that question could potentially impact the future of funding for standers. “The dynamic stander will have an additional cost compared to the passive stander,” Damcott acknowledges. So if children start a dynamic standing program early enough and stay in the program for perhaps a year, could they then be switched if necessary to a lessexpensive passive stander that will maintain their bone density?

“Insurance companies might be more willing to cover a dynamic stander at first, and then when (the children) outgrow that, say, ‘Yes, we’re willing to cover a passive stander,’” Damcott says.

Blochlinger and Damcott are recruiting non-weight-bearing children for the new six-month study. Because of such conditions as spinal muscular atrophy and orthopedic deformities and leg contractures, some of the children cannot be placed in standers. But they will undergo a bone density scan to determine if they are losing bone density, even as the children in the passive and dynamic standers are maintaining and gaining bone density.

Says Damcott, “We didn’t want to shoot ourselves in the foot by saying passive standing maintains bone density so the insurance companies would say, ‘It’s not improving it.’” If non-weight-bearing children are found to be losing bone density while children in passive standers are maintaining theirs — then funding sources may be more amenable to paying for standing equipment.

Researching the Research Process

In addition to their discoveries related to passive and dynamic standing, Blochlinger and Damcott say they have learned a lot about the research process itself — findings they discussed at Permobil’s Power of You clinician event last summer in Nashville.

Compared to other standing studies that have involved just a couple of children, this study has a large number of subjects. Damcott and Blochlinger say they’ve taken a number of steps to encourage compliance among the children, families and teachers involved in their study.

For instance, Damcott says, “We recruited children that were already participating in a passive standing program and had medical clearance from their physicians to either passively stand or to trial the new dynamic stander.” She adds that rather than have the children make separate trips to a clinic or lab to do their standing, she visits and observes them in their regular environments: “We moved into their classrooms to fit into what they were doing prior to the study.”

Says Blochlinger, “We wanted to be as least disruptive as possible… We have to try to fit into their lives, not be a problem for them.” She adds, “We really took the time before doing the study to educate them as to why we were doing the study and ask for their support as opposed to just going in and saying (to teachers), ‘We’re doing a study and you have to let us into your classroom because the parents said so.’ I’m involved with a couple of other studies here at the hospital, and you get much more compliance when you get the people on board before you start the study.”

Both researchers say they’ve received great support for the study from the children’s families and teachers.

“It’s exciting,” Blochlinger says. “We have a great group of parents that we’re working with. That’s part of the reason we decided to go ahead and continue (the study). The families are very compliant, and when we’re seeing results, we want to keep going.”

Damcott says she makes a point of participating in classroom activities such as music time, and helping teachers and aides whenever possible. She has battle scars to show for her efforts — “She has been bitten,” Blochlinger admits — but Damcott says, “It’s all part of a successful research effort.”

“You give as much as you’re getting from them, so we really do try to help out — an extra hand here, an extra hand there,” she says. “That goes a long way.”

This article originally appeared in the April 2010 issue of Mobility Management.

In Support of Upper-Extremity Positioning