Anatomical Facts about Baby’s Anatomy and its implication on correct positioning in slings
Development of baby’s spine and hips
A newborn baby’s spinal column is not double-S-shaped when in upright posture as is the case with an adult person. When a baby is born the spine is rounded in the shape of a C. The baby’s spine straightens up in 3 stages over a period of 1 year approx. This means that a human being’s spine will not be capable of adequately absorbing shocks and movements until it has reached the age of finding its feet. Its bending and stretching muscles which support the head and are required for sitting, crawling, and walking will gradually strengthen in interaction with the developing spinal column.
The intervertebral discs of an adult consist of cartilage with a gelatine core, broadly speaking. They are to protect the spinal column from tensile forces as occurring in an oblique position. They are not supplied with blood.
The tissue of a newborn baby’s intervertebral discs, however, are supplied with blood, and their final state and shape, as known of an adult, will only be reached when the respective section of the spinal column is erect. This is the reason why the intervertebral discs of a baby are very delicate, and its spinal column must not be exposed to tensile strain.
Likewise, a newborn baby’s pelvis as well as its hip joints are immature. The ossification of the pelvis and the hip joints (the process of cartilage becoming bone) is a process which takes place over a longer period of time. Even at pre-school or primary school age it is still possible to carry out hip corrections on children if justified by diagnostic findings. This means that the baby should be carried in an orthopedically correct position not only during the first weeks to support maturing and developing the hips and spinal column. These criteria shall play an important role during the whole period of carrying.
What does this mean for carrying your baby?
Good support
If we carry our baby in a woven wrap sling or a carrier, its back needs to be firmly supported and wrapped up like in a bandage. The younger a baby is the more important it is to support the spine on its whole length because there are not enough muscles to support the back and also the intervertebral discs cannot act as shock absorbers yet. Also important is that the baby needs to be able to curve his back when asleep. Even older children’s muscles relax when they are asleep and the sling needs to compensate this by good support of the rounded back. The sling should fit tightly like a bandage so the baby’s back cannot slump in it. You can test if back slumps by bending forwards: the child should not ‘fall away’ from the body of the carrying person
The M-position
There is an ideal leg position which centers the femur head right in the middle of the hip socket and thus aids the development of baby's hips. It's often described as M-position, frog-position or spread-squat-position. In this position the baby's knees are higher up than his bottom and that his legs are spread apart ca. 90° (for those with medical background: legs should be flexed min. 100°, abduction should be 30-45°). Babies automatically assume this position when lifted up, because it's also ideal for being carried on the mothers hip. Also babies treated for hip dysplasia using a Pavlik harness or Frejka pillow have their legs in this position.
A baby carried in the M-position will have a rounded back because the tilt in the pelvis causes the spine to become rounded and vice versa. You can see this in the left-hand photo showing a newborn in a red wrap.
In a cradle carry (baby is lying on her back in a hammock-style sling) a correct M-position cannot be achieved because her legs cannot be spread. So this position is not recommended at all by hip dysplasia specialists8. Instead upright positions, especially on the mothers hip are better for the hip, if a carrier supports correct positioning and a round back.
Here are some pics showing the M-position in a newborn, a 4-month old and a toddler:
A newborn baby’s spinal column is not double-S-shaped when in upright posture as is the case with an adult person. When a baby is born the spine is rounded in the shape of a C. The baby’s spine straightens up in 3 stages over a period of 1 year approx. This means that a human being’s spine will not be capable of adequately absorbing shocks and movements until it has reached the age of finding its feet. Its bending and stretching muscles which support the head and are required for sitting, crawling, and walking will gradually strengthen in interaction with the developing spinal column.
The intervertebral discs of an adult consist of cartilage with a gelatine core, broadly speaking. They are to protect the spinal column from tensile forces as occurring in an oblique position. They are not supplied with blood.
The tissue of a newborn baby’s intervertebral discs, however, are supplied with blood, and their final state and shape, as known of an adult, will only be reached when the respective section of the spinal column is erect. This is the reason why the intervertebral discs of a baby are very delicate, and its spinal column must not be exposed to tensile strain.
Likewise, a newborn baby’s pelvis as well as its hip joints are immature. The ossification of the pelvis and the hip joints (the process of cartilage becoming bone) is a process which takes place over a longer period of time. Even at pre-school or primary school age it is still possible to carry out hip corrections on children if justified by diagnostic findings. This means that the baby should be carried in an orthopedically correct position not only during the first weeks to support maturing and developing the hips and spinal column. These criteria shall play an important role during the whole period of carrying.
What does this mean for carrying your baby?
Good support
If we carry our baby in a woven wrap sling or a carrier, its back needs to be firmly supported and wrapped up like in a bandage. The younger a baby is the more important it is to support the spine on its whole length because there are not enough muscles to support the back and also the intervertebral discs cannot act as shock absorbers yet. Also important is that the baby needs to be able to curve his back when asleep. Even older children’s muscles relax when they are asleep and the sling needs to compensate this by good support of the rounded back. The sling should fit tightly like a bandage so the baby’s back cannot slump in it. You can test if back slumps by bending forwards: the child should not ‘fall away’ from the body of the carrying person
The M-position
There is an ideal leg position which centers the femur head right in the middle of the hip socket and thus aids the development of baby's hips. It's often described as M-position, frog-position or spread-squat-position. In this position the baby's knees are higher up than his bottom and that his legs are spread apart ca. 90° (for those with medical background: legs should be flexed min. 100°, abduction should be 30-45°). Babies automatically assume this position when lifted up, because it's also ideal for being carried on the mothers hip. Also babies treated for hip dysplasia using a Pavlik harness or Frejka pillow have their legs in this position.
A baby carried in the M-position will have a rounded back because the tilt in the pelvis causes the spine to become rounded and vice versa. You can see this in the left-hand photo showing a newborn in a red wrap.
In a cradle carry (baby is lying on her back in a hammock-style sling) a correct M-position cannot be achieved because her legs cannot be spread. So this position is not recommended at all by hip dysplasia specialists8. Instead upright positions, especially on the mothers hip are better for the hip, if a carrier supports correct positioning and a round back.
Here are some pics showing the M-position in a newborn, a 4-month old and a toddler:
For more on this and information on infant hip development see:
http://www.hipdysplasia.org/Developmental-Dysplasia-Of-The-Hip/Prevention/Baby-Carriers-Seats-and-Other-Equipment/
pictures and some text are from fellow Clauwi-trained babywearing consultant Mirjam Brockmann.
Read: Criterias of a good baby carrier
http://www.hipdysplasia.org/Developmental-Dysplasia-Of-The-Hip/Prevention/Baby-Carriers-Seats-and-Other-Equipment/
pictures and some text are from fellow Clauwi-trained babywearing consultant Mirjam Brockmann.
Read: Criterias of a good baby carrier