The term “tone” refers to the tension in a muscle. Every muscle has a certain abount of tone or tension when it is relaxed and this is necessary for the muscle to work efficiently. When a muscle is working, it contracts and shortens. Once it has finished working, it relaxes and returns to its resting position. Difficulties arise if a muscle has too much tension “hypertonus” or too little tension “hypotonus”. Following a brain injury, it is common to see changes in muscle tone. It is important to note that muscle tone is not the same as muscle strength as it is not under voluntary control.
How do I know if my student is having difficulties with changes in their muscle tone?
Changes in muscle tone following ABI can occur in varying degrees from mild to severe and may impact different muscles. As the student recovers from the injury, and with therapeutic intervention, the abnormal changes may improve. However, many students will have residual changes in muscle tone which may impact on their movement and function.
Your student may seem stiff or rigid in all limbs, on one side of his/her body, or in one half of the body (either the upper or lower extremities). Students with high muscle tone may have delayed gross and fine motor skill development, have difficulty “relaxing” his/her muscles, may maintain a fisted hand, or may present with very stiff legs that appear to move like scissors when standing or attempting movement.
Your student’s limbs may seem floppy or loose, and he/she may often seem fatigued and prefer to lie down versus sit upright. They may also attain her motor milestones on the late end of average or later than average.
Tonal problems can be a combination of hypertonicity and hypotonicity eg. The student may have a hypotonic ‘floppy’ shoulder while the hand is hypertonic ‘stiff’. Some students may have increased tone that present as spasms – jerky movements which may be painful or throw them off balance. Some student may receive Botulinum Toxin A (“Botox®) injections to help relax their hypertonic muscles.
What can I do to help my student overcome difficulties with changes in their muscle tone?
Every student will have different problems due to changes in tone so there are no simple strategies that will help all children. Points to keep in mind are:
- A student may need to wear hand, arm or leg splints (orthoses) to help control tone. If the student has hand or leg splints, encourage them to wear them as stated in their wearing regime.
- Contact the students’ parent and therapist if tone becomes difficult to manage or prevents their participation in classroom activities.
- If you notice an increase in the students’ tone that does not decrease with rest, encourage the family to seek a medical review.
- Fatigue may increase muscle tone so the student may need a short break from an activity to allow their tone to reduce.
- If a limb does show increased tone, DO NOT pull on it to try to correct the position. The best method is to apply slow, sustained pressure in the opposite direction while the student is relaxing.
Queensland Paediatric Rehabilitation Service
Lady Cilento Children’s Hospital
Level 6, 501 Stanley Street, South Brisbane 4101
t: 07 3068 2950
t: 07 3068 1111 (general enquiries)
f: 07 3068 3909
In an emergency, always call 000.
If it’s not an emergency but you have any concerns, contact 13 Health (13 43 2584). Qualified staff will give you advice on who to talk to and how quickly you should do it. You can phone 24 hours a day, seven days a week.