You may never encounter a pediatric patient with cerebral palsy. If you
did, chances are you may find the solution to orthotic treatment already on
your supply shelf, needing only some customized adjustment. To make a truly
useful orthosis for a child with cerebral palsy, you may also need to hit the
books to hone your knowledge of body mechanics and kinematics.
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| © 2012/Realistic Reflections/Getty Images |
According to the Centers for Disease Control and Prevention (CDC),
cerebral palsy affects roughly one in 303 8-year-old children in the United
States. In 2006, cerebral palsy prevalence was significantly higher in black
and white children than among Hispanic children. Cerebral palsy occurred 1.2
times more frequently among boys than among girls that same year.
Goals of orthotic management
Spastic cerebral palsy is the most common type of cerebral palsy, found
among approximately 80% of children with the disability. Although orthotic
intervention has adjusted in small ways to accommodate new research into body
mechanics and gait, the overall goals are the same. According to the
International Society of Prosthetics and Orthotics (ISPO), the goals of lower
limb orthotic management of cerebral palsy are to correct and/or prevent
deformity; to provide a base of support; to facilitate training in skills; and
to improve the efficiency of gait. Other goals include increasing range of
motion, maintaining or improving levels of function and stability; maintaining
muscle length as the bones grow, and preventing or overcoming some of the
secondary effects of the disability leading into adulthood.
No single treatment is appropriate for every child, but it is generally
agreed that the sooner intervention is started the better the outcome.
In the Journal of Prosthetics and Orthotics, Christopher
Morris, MSc, SR Orth, suggested that some degree of compromise between
affecting body structure vs. overcoming activity limitations is necessary
“because orthoses prescribed to prevent or correct deformities can impose
additional activity limitations by restricting movement.” He suggested
that “normal functional development can be impeded by impairments of
coordination and movement. Orthoses can maintain optimum biomechanical
alignment of body segments encased with the orthosis. These effects may enable
children to overcome activity limitations by focusing training on unrestricted
parts of their bodies over which they have better control.”
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| Elaine Owen |
A multidisciplinary team including an orthotist, physical therapist and
an orthopedist can advance a child with cerebral palsy along the continuum of
care throughout his development. This team, coordinating with a family-centered
approach to care, should encourage optimal use of an orthosis within the
prescribed treatment plan.
There are different and evolving schools of thought regarding the use of
orthotic intervention. Some practitioners believe less bracing is better and
that positive development can come from muscle stretching, training and
strengthening exercises. There is a trend toward making below-the-knee only
orthoses and using flexible AFOs to maximize gait and performance. Now,
treatment has found its way toward options such as electrical stimulation and
the use of botulinum toxin A injections and the subsequent challenge of
creating orthoses based on the muscle dynamics that result.
Where to start
Orthotists need to take time to consider real-world function and
consider the effect of any orthosis on a child’s ambulatory skills,
whether it is on the playground, in the park, the schoolyard or the backyard,
said John Kooy, CO (c), Holland Bloorview Kids Rehabilitation Hospital,
Toronto. “We have to consider what’s happening in those settings vs.
the clinical environment of a wide open, flat hallway. Does that necessitate a
change in the orthotic prescription? I don’t think we know enough to say
whether it does or not.”
It is important to remember that providing orthotic care to this patient
population does not follow a one-size-fits-all approach. An orthosis must fit
well, and control the ankle, forefoot and hindfoot. Total contact is important
because of the deviations in planes of the foot. A loose brace may cause skin
breakdown; an orthosis that is dorsiflexed may cause discomfort and decreased
function in a child who doesn’t have adequate dorsiflexion range of
motion.
According to Scott Amyx, CO, senior orthotist at the University
of Wisconsin, Hospital and Clinics, Orthotics. Lab, in Madison, Wisc., getting
a good skeletal alignment is the foundation to getting the muscles to operate
more effectively. Patients with spasticity may have inherent body weakness that
affects their inability to control their muscles. Strengthening those muscles,
once thought to increase spasticity, is now a critical part of a
multidisciplinary approach to treatment.
“It’s crucial you get decent alignment. By controlling the
alignment we’re going to have a bigger impact on the spasticity,”
Amyx told O&P Business News.
“Years ago the common wisdom was to put all these bumps and
grooves into the footplate and that’s going to reduce spasticity by the
neurosensory input. That’s been pretty much proven that it really
doesn’t. If that were the case we’d be able to put a foot orthosis in
a shoe and they would have a reduction in spasticity. That didn’t happen.
We still have to use AFOs.”
Amyx said a neutral alignment reduces the power of over-powerful
muscles, and gives underused and underpowered muscles a chance to increase in
strength and be more effective.
“If you stretch a muscle too far it loses a lot of its strength and
effectiveness. If you have a kid who’s really pronated, all the medial
muscles are overstretched and the lateral muscles are pulling on the foot. If
we can get them into neutral heel alignment and get the forefoot in the right
position, that would help reduce spasticity more because of the skeletal
alignment rather any sort of bumps or grooves we’re putting in the bottom
of the footplate.”
Elaine Owen, MSc SRP, MCSP, superintendent and clinical
specialist physiotherapist at the Child Development Centre in Bangor, UK, told
O&P Business News that segment kinematics are just as
important as joint kinematics when considering AFOs. Owen presents a course on
shank and thigh kinematics at the Rehabilitation Institute in Chicago.
“If you see segments and joints as completely independent, you can
get some perspective. When the foot and the shank kinematics are correct, you
can more easily correct the thigh, pelvis and trunk kinematics and
kinetics.”
She stressed that in addition to the angle of the ankle — in an
AFO, the shank relative to the foot — the shank to vertical angle of an
AFO footwear combination (AFOFC) is equally important in building a foundation
for orthotic intervention.
“The reason for that is because small adjustments to the shank to
vertical angle can make big changes in gait, particularly in children with
neurological conditions.”
AFO options
According to a consensus report from the ISPO, AFOs that control the
foot in stance and swing phase can improve gait efficiency in children with
cerebral palsy (GMFCS levels I-III). The report suggested little evidence
supporting the use of orthoses for the hip, spine or upper limb.
The trend toward using less rigid materials to craft AFOs allows the
child more motion, according to Amyx.
“One of the products we just started exploring is the Ultralex
Safestep. It’s got polyurethane “bumpers” and stops so we can
modulate planterflexion and dorsiflexiojn to give kids more motion than we have
in the past, but we can slow down some of the extraneous motion we don’t
want. That looks really promising,” he said.
Owen advocates the use of an AFOFC.
“With AFOs, the footwear hasn’t been recognized as being as
important as it really is. The footwear is as important as the orthosis.”
She said it is acceptable to allow plantarflexion angles of the ankle in
the AFO when required.
“Traditionally there has been a lot of use of 90· angle of
the ankle in the AFO, when that might not always be the optimal alignment of
the foot relative to the shank. That may change the bony alignment of the foot,
and the child may not be extending their knee fully in gait. They might walk
with a flexed knee gait and therefore not be stretching their calf
muscles.”
Owen disagrees with the notion that the foot has to always be supported
at 90·and that by failing to do so, the child cannot get good knee
extension in gait.
“If you come from a belief that you can put the ankle at any
position and it’s the shank to vertical angle and the alignment of the AFO
footwear combination that will give you the knee extension, then you can get
away from always using the 90· ankle angle. It’s the shank to
vertical angle that will determine gait as opposed to the angle of the ankle in
the AFO, as long as that is optimal. Then we can choose any ankle angle that is
appropriate and we can design AFOFCs optimally for each leg of each
child.”
Footwear designs can change the effectiveness of the orthosis.
“Determine the optimal angle of the ankle in the AFO, determine the
optimal shank to vertical angle of the AFOFC and then determine the optimal
heel and sole design of the footwear,” Owen said.
Based on an algorithm for designing and tuning AFOFCs, it is best to
tune the alignment, then tune the heel design for entrance into mid-stance,
then adjust the sole design for exits from mid-stance. For some abnormal gaits,
she recommended a point loading rocker position adjusted for pathology.
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| Gregg Beideman |
Functional electrical stimulation
A recent study conducted by the National Institutes of Health was the
first to investigate the use of the WalkAide for the treatment of dropfoot in
children with cerebral palsy. The goals of the study were to compare efficacy
vs. an AFO and overall compliance.
Twenty children in the study wore the WalkAide 6 hours a day for 6
months. The children wore the device during daily activities; once they were
settled in for the night, they did not wear orthoses.
Gregg Beideman, DPT, a rehabilitation specialist with Innovative
Neurotronics, the device manufacturer, fit the device on the children in the
study. He told O&P Business News that 95% of the children
continued with the device after the study ended.
“There was great compliance,” he said. “There’s been
a hesitation to use it because you’re afraid whether they’ll continue
to use it. They not only continued to use it but they preferred it. All of the
kids in the study had an AFO made for them at some point in thier lives, but
only a handful of them were still wearing them regularly and some refused to
wear them altogether. Compared with an AFO over time, they continued to show
improvement. The more they wore the device the better clearance they had during
swing over time.”
The device triggers an electrical impulse into the peroneal nerve that
signals the muscles that pick up the toes during gait. It also tries to
reconnect the neural signal from the foot to the brain that is impaired with
children with cerebral palsy.
“Over time, that can restore that ability to pick their toes up
even when they’re not wearing the device, something an AFO can’t
do,” Beideman said. “We’re seeing serious improvement in that
connection but we need more research to formalize that that can happen. This is
the first study in kids.”
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The device, previously limited to adults because of the cuff size, now
has a cuff that fits children as young as 3 years old. In the past, orthotists
had to make custom cuffs to fit the device to children.
“We’ve been able to change the waveforms so smaller legs can
tolerate the electricity,” Beideman said. “It was something that
physicians didn’t previously recommend because they didn’t know the
settings could be modified for children. However, now, it’s become a
little more mainstream for the physician to recommend the Walk Aide and an
orthotist to deliver it.”
Beideman said children tend to have better outcomes than adults because
treatment can positively affect gait patterns before they become habit. Amyx
has seen some positive results with the WalkAide, but said parents may shy away
from using it because it is not typically covered by insurance.
While the most important results of the study that will impact children
with cerebral palsy are set to be published sometime this year, Beideman thinks
there will be more advances in functional electrical stimulation so the
technology can be more readily used for other parts of the body. “This is
going to help kids with cerebral palsy with their upper extremity and hip
flexors. You’ll see that trend in the next 5 years,” he predicted.
But for now, the technology can be combined with
orthotic management and perhaps down the road, actually built into an orthosis.
“FES isn’t always the only solution; while it predominantly does well
by itself, there might be a hybrid that can transition from a bracing solution
to an FES solution or a combination thereof,” he said. Between the therapy
and the orthosis, “a nice working relationship allows you to do that,
instead of just one or the other.”
Pharmacological and alternative intervention
Dynamic orthoses can complement other treatments, including botulinum
toxin therapy and post surgical recovery. At the Holland Bloorview Kids
Rehabilitation Hospital, clinical and orthotic management of children with
cerebral palsy has included the use of botulinum toxin A for more than a
decade.
According to Darcy Fehlings, MD, MSc, FRCPC, associate professor
of Paediatrics, University of Toronto and senior scientist at the Bloorview
Research Institute, there are three main indications for the use of botulinum
toxin A in a child with hypertonia: a potential to improve motor function, ease
of caregiving, and painful muscle spasms.
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| Darcy Fehlings |
“Botulinum toxin can be quite effective. We have evidence that it
shows improvement in equinus management and gait functioning in children who
are ambulatory with cerebral palsy in the short term. Most of the trial
evidence is for 6 months. After that, the child comes back in to be reassessed
for a repeat reinjection.
“Under 7 years of age, we might consider botulinum toxin injection
every 6 to 9 months. As the children get older the indications tend to narrow a
bit to improve gait and motor function. After this age we are often injecting
less frequently,” she told O&P Business News.
Fehlings said her team often uses botulinum toxin A in conjunction with
serial casting to help improve range of motion or flexibility, particularly in
the gastrocnemius muscle. Serial casting can cause weakness in the muscle,
which may require more stability in the orthosis. Increased stability allows
for improved function as the child improves his range of motion as a result of
therapy after receiving botulinum toxin.
They follow that with a hinged AFO for up to 6 hours daily to help
stretch the muscle while the child is walking. Fehlings and her team also
perform a modified Tardieu evaluation to assess where the child first develops
hypertonia in a passive stretch.
“We look at that angle. Then we keep stretching the muscle to see
what the passive flexibility is of the muscle. The largest distance between the
first catch and the second catch…that’s the dynamic range that the
botox will be effective in. So as long as that range is significant, and that
depends on the joint, then botulinum toxin can be effective.”
An orthotist who encounters a child with cerebral palsy who has
undergone botulinum toxin treatment needs to consider the level of function and
the goals of the patient and family.
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“We want to consider functions such as going from floor to
standing, which may call for a little more ease of mobility around the ankle.
With stair transitions, we try to keep them in a hinged AFO during that
time,” Kooy said. “As they start to get older, levers become longer,
weight gets greater, and when evaluatingt their overall strength and range of
motion, do we need to consider hinging the AFOs with limitations, or should we
consider more of a rigid style AFO?”
Kooy said in higher classes of the GMFCS levels, at level III, the aim
is to reduce the tendency to crouch, but that comes with risks. “Is it a
better option to stay with a rigid AFO vs. allowing them some more movement at
the ankle perhaps resulting in increased crouching — which would decrease
function and increase energy expenditure in gait?”
“With botox, because they have more flexibility, we can get them
into a 90· AFO easier than before botox,” Amyx said. “With
dorsal rhizotomy, we have to go to a more solid ankle AFO initially with dummy
hinges and hopefully we can articulate it later. Most kids are stereotypically
very weak after the rhizotomy is done. They can’t use an articulated AFO
or they might sink into crouch.”
Novel approaches
Amyx approaches supramalleolar orthoses differently than most by
articulating them.
“We do that because an SMO primarily controls medial-lateral
instability of the foot. And so if you have a standard SMO, as they advance
their tibia over the foot, it’s coming out of those supra mallleolar
“wings” at the terminal stance, so they’re able to pronate
inside the brace. We decided to articulate them so when they come forward
we’re still able to use the tibia to try control the foot and so as they
advance their tibia they’re getting a ground reaction force that’s
pushing against the tibia to help control the foot. Typically when we do those,
they’re free-motion, full plantarflexion and dorsiflexion; we’re
concerned with the pes planovalgus,” he said.
New technology and advances in gait mechanics have evolved so that
practitioners are using orthoses and biomechanics to access the nervous system,
Owen said. “That requires a lot of perfect practice. Children with
disability find it hard to learn by trial and error. They often have to have
errorless learning. They need to get it right to learn it, and using orthoses
so they can get it right to learn it is a new way to use orthoses. We’ve
always used orthoses to help bony alignment and perhaps stretch muscles.
Accessing the nervous system is a really important way of using them,
particularly with neurological conditions, and children who are learning to
walk with them,” she said.
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As part of a hospital based multidisciplinary team, Amyx acknowledged he
has access to treatments that some private practices may not offer.
“Typically not found in a private practice, we have the GAITrite, a mat
that with sensors that records temporospatial data, and a gait lab,” he
said. The multidisciplinary team at the University of Wisconsin comprises
rehabilitation professionals, occupational and physical therapists and an
orthopedic surgeon. Holland Bloorview also focuses on multidisciplinary
treatment and family centered care.
Kooy acknowledged that there is nothing drastically different in
orthotic treatment but there is now more careful examination of the literature.
“People are trying different ideas. It still depends a lot on
evaluation,” he said.
Owen concurred, and said moving forward, a critical goal of using
orthoses for children with cerebral palsy or other pathologies is “finding
ways to make these things work better than they used to.” — by
Carey Cowles
For more information:
Cerebral Palsy Occurrence in the US. Available at:
http://www.cdc.gov/Features/dsCerebralPalsy/. Accessed March 1, 2012.Kelley R. Orthotic management of cerebral palsy. O&P
Business News. April 15, 2002.Morris, C. Orthotic management of children with cerebral palsy.
J Prosthetic Orthot. 2002; 14(4):150-158.Owen E. The importance of being earnest about shank and thigh
kinematics especially when using ankle-foot orthoses. Prosthet Orthot
Int. 2010; 34: 254-269.Recent consensus on developments in the management of cerebral
palsy. The International Society of Prosthetics and Orthotics. Newcastle Upon
Tyne, UK. Jan. 14-15, 2010.
Disclosures:
Amyx, Kooy and Owen have no relevant financial
disclosures. Beideman is employed by Innovative Neurotronics.
