Low Muscle Tone
“Muscle tone” is often confused for “muscle strength” and although related, they are not interchangeable terms. Tone refers to the amount of tension in a muscle when at resting state (not actively contracted). Muscle tone helps our bodies maintain posture. Low muscle tone is characterised by the muscles having less tension at resting state and feeling “floppy”. Children who have low muscle tone will often need to “work harder” during physical activities to keep their muscles “activated”. It can also be more difficult to maintain their posture when sitting or standing for extended periods of time. This extra effort can lead to increased fatigue. Low muscle tone can also delay a child’s gross and fine motor skills.
Low muscle tone can be a symptom of conditions such as a central nervous system disorder or Down’s syndrome. When children have low muscle tone unrelated to a separate condition this is sometimes called benign congenital hypotonia – there is still a lot unknown about this but there appears to be a genetic connection.
Although often debated, muscle tone has been shown to develop and increase over an extended period of time (several years). Occupational therapy, physiotherapy and speech therapy are sometimes used to support children with low muscle tone. In the short term, warm up activities can help increase muscle tone temporarily by activating the muscles. For example, in order to sit up straight at a table for handwriting, a child may benefit from briefly jumping on a mini trampoline beforehand.
Ligament Laxity or joint hypermobility
Ligament laxity (also sometimes known as joint hypermobility or being “double jointed”) simply refers to “loose ligaments”. Its severity varies from person to person. It does not always effect the entire body – for example, some people can have ligament laxity in their upper body but not their lower body. Ligament laxity is usually genetic or as a result of previous injury. People with ligament laxity are more prone to injury or having accidents, balance and overall movement can be effected. During physical activities there will often be increased fatigue for people with ligament laxity.
If your child has ligament laxity there are a variety of ways to provide support. It is important to have a healthy diet and healthy weight, increase overall muscle strength and endurance and improve posture and body awareness. All of this reduces strain and supports the strength of the joints. As with low muscle tone, occupational therapy and physiotherapy commonly support children with ligament laxity. Hydrotherapy is often recommended as it is a “low impact” therapy. Swimming and bike riding are good “low impact” activities for children to increase strength and endurance with less strain on the joints.
References
1. Department of Occupational Therapy, Royal Children’s Hospital, Melbourne 2005, http://www.rch.org.au/uploadedFiles/Main/Content/ot/InfoSheet_C.pdf
2. Little, K 2014, ‘Multi-Ligament Laxity’, The Pediatric Upper Extremity, pp 1-13.
3. http://www.ninds.nih.gov/disorders/hypotonia/hypotonia.htm
4. http://www.skillsforaction.com/rethinking-low-muscle-tone