Early intervention is especially important for children with tone problems
According to Barbara Hypes, PT, a self-employed therapist from Milwaukee, early intervention is especially important for children with conditions such as Down syndrome and cerebral palsy in which hypotonia is prevalent.
"Doctors typically assume that children with Down syndrome will eventually catch up [with their peers], but from my experience, the children who get early therapy develop much better because they don't learn to compensate [for inappropriate postures] and they gain better motor control," said Hypes.
"These children should be referred immediately for therapy, and by two to three months of age they should be able to handle therapy one to two times weekly; by three to four months old, they should be able to handle more frequent therapy from a variety of disciplines."
Hypes, who teaches her approach through seminars conducted by Therapeutic Services Inc., Brooklyn, NY, says physical, occupational and speech-language therapies play vital roles in helping children with hypotonia reach their functional potential.
"In my experience all disciplines of therapy focus on increased proximal control as a basis for extremity functions in very young children," she said. "You can't separate out responsibilities. The hypotonic child has a floppy trunk, so everybody has to start at the base."
According to Hypes, the physical therapist directs this extremity function toward gross-motor tasks such as independent sitting, creeping and kneeling, and then transitions higher against gravity (standing).
The occupational therapist directs the extremity control to lead to better eye-hand coordination, reaching in space, hand manipulation and vestibular experiences in play. The speech pathologist focuses on this early proximal control to allow greater rib mobility for thoracic breathing and breath support for sound production. "The speech pathologist also works for greater oral motor control and tongue-lip-cheek dissociation in feeding as a basis for the motor foundation needed for speech development," she added.
For children who don't have a syndrome but have hypotonia, therapy is usually started at age four to six months, when hypotonia is typically detected due to poverty of movement and lack of variety in it. In addition, children with hypotonia typically have a weak cry and weak, underdeveloped muscles. They have difficulty with postures because they are "floppy."
"For example, in head control [children] turn the activity on and it is a burst of movement, then they turn if off and throw their heads back, stacking it on their shoulders instead of holding it there with muscle control," she explained. "Although we normally stack our joints to some degree, children with hypotonia use that as their primary way of holding their body together instead of using co-activation."
In her evaluation, she also looks at how their vestibular systems work in response to movement. Many children with hypotonia appear to be nonresponsive to being moved. Hypes believes that this is a sign that the children are not interpreting the movements imposed upon them. Since these children don't have a lot of experience with independent movement, they don't have good integration of what their bodies should be doing during movement.
Another important area to evaluate and correct early on in children with hypotonia is vision. Since these children frequently stack their heads on their shoulders in an up and back oriented posture, they develop visual gaze to compensate for poor posture. If this pattern is maintained over a long period of time, commented Hypes, it will be very difficult to change their head control.
Some techniques used in the treatment of children with hypotonia include joint compression that is graded to approximate the joints without overloading them, and joint distraction that is graded to align the joints without overstressing them. Hypes noted that both of these techniques promote increased co-activation of the muscles around the joint, which helps the child hold that joint in alignment against gravity.
Get Children Moving
"Movement in general is good therapy," said Hypes. She uses the Swiss ball as a therapy tool to promote increased joint compression, vestibular stimulation and righting in space, in addition to promoting strengthening and endurance.
"Using the ball or another surface to keep them up off of the ground helps keep them more dynamic in space," explained Hypes. "I work in as high a developmental position as possible with a minimal amount of joint stacking."
When treating children with hypotonia be cautious of ligamentous laxity. "This can affect the stability and alignment at all the weight-bearing joints, so the therapist shouldn't allow children to maintain postures where they are passively stacked onto their joints," stated Hypes.
One example of this is having a child with hypotonia unsupervised in a standing frame because he may tend to shift his weight to one side and collapse into that one hip. Although standing frames are designed to support and inhibit this shift, noted Hypes, these children are so hypermobile and loose that they can continue to stack their weight-bearing joints even in adaptive positioning devices. "Therefore, it is important to teach caregivers about the alignment we are hoping to maintain using positioning."
The reason therapy needs to be constant for a long period of time is because therapists have to spend a lot of time waiting for the child's response to the stimuli, explained Hypes. "I tell parents that their children turn on and off like a computer. They turn the computer on and get a burst of energy, but before they can save the informationthe correct response to the stimulithey turn the computer off. The goal (is) to get them to save the information before they turn off the computer, which is when the brain integrates the information."
Because hypotonic children often don't show response immediately, therapists and parents have a tendency to give up on what they are doing and look for another activity. These children, however, need the activity to be repeated.
"So I tell therapists wait, wait longer, and then wait even longer before changing activities," said Hypes. "If you don't sustain the activity you reinforce the child's burst of activity followed by termination."
Waiting for this response is key in the treatment of hypotonia. For example, if the treatment goal is to increase head control, Hypes will distract the child's shoulders which may produce a response of a quick burst of throwing the head backward. She continues to distract the shoulders to promote alignment and co-activation in the shoulders and upper back, but uses her fingers to inhibit the head from being thrown backward. The child may then put his head upon the support surface and although it may appear that he is doing nothing, Hypes said she can feel activity where her hands are at the shoulders and upper back.
"If I wait long enough, the next time the child lifts his head he will lift it with good elongation in the neck and an emerging chin tuck," said Hypes. "By sustaining the same activity and molding the activity, I inhibit the quick burst response and facilitate and promote co-activation."
Therapists can help children with hypotonia learn how to move their bodies against gravity using co-activation in space rather than stacking their joints into their base of support, emphasized Hypes. "This saves the integrity of the joints over long-term use."
Tom Kerr contributed to this article.