Low Tone (Hypotonia)
Low muscle tone, or hypotonia, is defined as a decreased resistance
of skeletal muscles to passive stretch. It is not a diagnosis, but a symptom of many neurologic conditions. Often times, especially in children, the cause of hypotonia cannot be determined.
In order to carry out motor activities, our muscles continuously receive input from our brains telling them when to contract and when to relax. In order to perform a motor task one set of muscles needs to contract while the others simultaneously relax. Generally, children with hypotonia do not respond as quickly to the brain telling their muscles to contract. They also have difficulty maintaining this contraction for an extended period of time. This may cause the child with hypotonia to have difficulty maintaining various body positions for a period of time. For example, maintaining an upright posture at a desk, standing in line or sitting upright in circle time are all difficult for children with hypotonia. Children with low tone may appear to have decreased body awareness and impaired movement in space. They may appear to have difficulty grading their movements including grading pressure (how rough to be with peers, how hard to press on writing implements, how hard to squeeze when giving a hug) Low tone can be seen together with sensory processing disorder but this is not always the case. Low muscle tone does not necessarily mean decreased muscle strength although the two can happen together.
Children with low tone may be affected in various ways. Please remember that every child is different and may exhibit some, all, or none of the following problems associated with low tone.
- Low endurance
- Does not “hold on” when being carried
- Poor core strength
- Poor regulation of breathing
- Increased amounts of drooling
- Messy eater
- Poor ocular motor skills
- Delayed fine motor skills
- Delayed gross motor skills
- Increased incidence of dislocation i.e. elbow dislocation as an infant or toddler
- Speech and language delays
- Difficulty with self care skills such as dressing feeding etc
Occupational therapy can help increase the brain’s ability to perceive change in muscle length. This may allow children with low tone to increase body and spatial awareness which may have a direct effect on clumsiness as well as the grading of movement. Core strength can also be improved which will have a direct effect on endurance, fine motor skills, gross motor skills, ocular motor skills and oral motor skills. These skills will affect speech and language development as well as self care skills.
- Increase core strength
- Perform activities on belly(coloring, watching TV)
- Sit on a therapy ball while coloring, performing tabletop activities
- Sit ups
- Catch/hit a ball from a superman position on belly (legs and arms off the floor)
- Heavy work/weight bearing activities (see proprioception on the sensory diet page)
- Perform resistive fine motor activities
- Play dough
beads ( a bead in which a knob on one end fits into a corresponding hole on a neighboring bead to link together. These beads come in various sizes ranging from very small to very big)
- Allow the child to sit in a supported seat in order to get dressed
- Use pencil grips
- Use slant
boards when writing or drawing