The infant at 5-7 months: Comparing movement in prone at 5 and 7 months

About the tutorial series 

I am in the process of writing guidelines for assessment of 5-7 month old infants with developmental delay. As part of this process I am reviewing my library of video clips of typical development. In this tutorial series I will be sharing my insights from this process. 

 I will post a new tut every few days illustrating aspects of 5-7 month motor development, culminating in guidelines for task oriented assessment of  a 5-7 month old infant with developmental delay.  Look here for more information about task oriented movement therapy for infants (TOMT 0-3)

Please note: Each tutorial is available for 1 week. Follow on Facebook for updates 

Development as learning to solve the motor problem

These  videos of Will in prone beautifully illustrates the amount of exploration, persistence and repetition is part of the process of  learning  how to  adapt weight distribution and alignment of body segments (postural adjustments) to support goal directed actions.  

Postural control and stability (weight distribution, alignment, anticipation and adaptation to perturbations)  is learned through a process of exploration, trial and error and persistent practice. 

This week's tutorial

In this week's tutorial you have an opportunity to compare Will's postural and movement abilities at 5 and 7 months. 
You also have an opportunity to post your thoughts, questions, and critique of my analyis in the Comments section at the end of the page. 

Will at 5 months 

At five months Will nas learned to roll from supine to prone and is at last willing to spend time in prone, and is very busy exploring how to maintain his balance as he starts to reach for toys.

  • He is starting to take weight on his forearms as well as on the hands with the elbows extended. 
  • He holds his head up with the face vertical. 
  • As before, pushing up onto his forearms and hands is supported by extension of the trunk  which now includes extension of the thoracic and the lumbar spine.
  • Mostly his hips are in some flexion, abduction with some knee flexion. From time to time you see him extending the hips and knees. 
  • With the torso lifted up off the support surface and some weight being taken on the upper extremities, Will's COM has shifted towards the pelvis. 
  • In order to maintain stability and balance as he explores looking around and reaching for toys, Will has to learn how best to realign the head, limbs and trunk to support his actions. 
  • You will see will exploring different options for shifting his weight over the pelvis and UE's  to maintain his balance. As he does this his COM shifts laterally and in a cephalo-caudal direction. 

WIll at 7 months

At 7 months two things stand out for me

Firstly the ability to transfer weight onto one UE  with effective postural responses in the trunk and pelvis to provide a stable platform for reaching with the contralateral hand take time to develop. In Will's case this only really present at 7 months. 

Secondly, the ability to support the head and upper torso on the UE, either on the forearms or on the hands with extended elbows, requires effective trunk extensor muscle action. 

W 7m prone 4.jpg      W 7m prone 13.jpg

More about development in prone 

For TOMT Subscribers
Videos of development at 5, 6, and 7 months 

More about a TOMT subscription 

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