Crossing the Midline

What is crossing the body’s midline?

Crossing the midline refers to the ability to reach across the middle (an imaginary line down the centre of the body). The arms and legs have the ability to cross to the other side. It is needed for most self-care tasks, being able to draw a line across a page without having to move it or switch hands in the middle. 

Why is crossing the body’s midline important?

Before midline crossing is established, children are usually observed to engage in tasks on only one side of their body, e.g.: reaching for an item placed on their left side with only their left hand. It promotes the coordination and communication of the left and right hemispheres of the brain. It also encourages bilateral coordination, the process of developing a dominant hand and development of fine-motor skills.

However, crossing the body’s midline is an important developmental skill needed for most self-care and play/sports activities. Everyday tasks such as writing, reaching towards your foot to put on a shoe and sock with both hands and hitting a ball with a bat. 

When your child spontaneously crosses the midline with the dominant hand, then the dominant hand is going to get the practice that it needs to develop good fine motor skills. If your child avoids crossing the midline, then both hands will tend to get equal practice at developing skills and your child’s true handedness may be delayed – This means that once a child starts school, learning to write will be much more difficult. They will have two less skilled hands rather than one stronger, more skilled hand. Difficulty crossing the midline also makes it difficult to track a moving object from one side to the other or track from left to right when reading, meaning reading can also be delayed.

Building blocks necessary to develop the ability to cross the body’s midline include:

• Bilateral integration skills (using both sides of the body at the same time).
• Core stability and trunk rotation
• Hand dominance
• Planning and sequencing
• Body awareness

You can tell there are problems with crossing the body’s midline if the child:

• The main sign of difficulty is when the child is noted to switches hands when writing, drawing, painting and colouring.
• They will use the hand that is nearest to the item e.g. uses left hand for activities on the left side of the body and right hand for activities on the right hand side.
• The child is noted to rotate their trunk to the opposite side when reaching across the body rather than crossing the body.
• The child is unable to tracking an object from one side of the body to the other.
• Has poor reading skills for their age and stage of development.
• Has poor pencil skills in relation to their age and stage of development, 
• Has no preference of foot when kicking a ball.
• Has difficulty engaging in gross motor activities e.g. crawling, skipping, star-jumps.

When you see difficulties with crossing the body’s midline, you may also see difficulties with:

• The child may struggle to use a pencil or paintbrush. They may try to avoid these types of activities are they know they are difficult. 
• The child my become angry or frustrated when trying to use fine motor skills due to less refined hand skills, this can lead to anger and frustration.
• The child may struggle with age and stage appropriate life skills and self-care tasks.
• They will have difficulties coordinating both sides of the body.
• Reading may be difficult due to inability to cross midpoint of the page.
• They may struggle to notice all of the details on a page when copying drawings or writing.

What can be done to improve the ability to cross the body’s midline?

• The child should be encouraged to join in on Bilateral Integration Skills (using both sides of the body at the same time).
• Use everyday activities to promote this e.g. put food on opposite side of table so the child has to reach across to get it. Put toys slightly out of reach. Play games such as balloon tag etc.
• Work on core stability and tummy muscles, games that include core stability and trunk rotation.
• Use crafting projects e.g. threading beads, cutting and pasting, folding paper.
• Use finger puppets (if age appropriate) e.g. placing finger puppets on one hand and encouraging your child to remove the puppets with the opposite hand.
• Make use of musical instruments and notice to encourage the child to bang blocks or percussion instruments together in their midline.
• Paly floor games such as Twister; Simon Says and obstacle courses.
• Use streamers, pomp oms and ribbons, encourage using two hands together or one in each hand following a sequence.
• Do marching games using their arms and legs – nursery rhymes if appropriate, YMCA; Macarena etc.
• Make use of stickers and tape – put it on the child’s arm and encourage them to take if off with the opposite hand.
• Throw and catch games with balls of various sizes. Target games and bat and ball games are good to encourage crossing the midline.
• Table tennis, snooker or other table top games.
• Push toys e.g. cars and trains – create a road for them to follow, make lots of twists and turns
• Encourage floor games where the child has to reach over to get something in order to play with it.
• Coin flipping, noughts and crosses and marbles can be used to promote crossing the midline

If left untreated, difficulties with crossing the body’s midline can lead to:

• The child experiencing increased pressure and anxiety especially if they have not mastered the self-care tasks expected for their age and stage of development.
• They may struggle to keep up academically due to difficulties with writing and reading. 
• They may struggle to keep up with work due to physically being unable to keep pace. This may result in work being illegible difficult to understand.
• The child may struggle with social activities such as sports and playground activities.