Children develop their muscular system as well as body awareness and balance through play, action and manipulation of objects. Naturally, for short periods of time, siting in W position is not harmful. However, when that becomes a preferred posture, or is often adopted, there are very serious consequences to the child’s development.
When in W position, children enjoy an increase in the base of support. That results in a more stable static posture, retarding the development of normal balance and protection responses, as well as muscular control of the trunk.
Children may choose to “W sit” simply because it is easier not to worry about balance while manipulating an object, however, this is also the preferred posture for children that suffer from neuro motor syndromes with distal hypotonia, like down syndrome and myelomeningocele.
“W seat” is detrimental to the development of trunk rotation abilities, lateral inclinations (involved in the action of reaching for an object) and weight transfer, as well as the pelvic and shoulder girdle dissociation. These are imperative qualities to the normal motor development of children as well as their manual abilities.
One could argue that W seat is the foundation for a hypotonic behaviour, in which the spines arches in a C curve and even the attention spam may be compromised.
Furthermore, trunk rotations and weight shifts over one side are the qualities that allow a child to maintain balance while running outside or playing on the playground and are necessary for crossing the midline while writing and doing table top activities.
“W seat” discourages a child from developing a hand preference. Because no trunk rotation can take place when W-sitting, a child is less inclined to reach across the body. Instead they pick up objects on the right with the right hand, and those placed to the left with the left hand.
“W-seat” is a deterrent to trunk rotation, which helps develop midline crossing and separation of the two sides of the body, needed for bilateral coordination. Good trunk control and stability, midline crossing and bilateral coordination are needed to develop refined motor skills.
From an orthopaedic point of view, in “W seat” the hip joints are in extreme internal rotation, an abnormal position.
Excessive use of a “W-seat” during the growing years puts undue stress on the hip abductors, hamstrings, internal rotators and heel cords, leading to the possibility of orthopaedic problems in the future. “W-seat” can lead to hip dislocation, and for children with pre-existing orthopaedic conditions, these conditions can worsen when major muscle groups are placed in shortened positions. The muscles begin to tighten, and this can lead to a permanent shortening of the muscle, which can affect coordination, balance, and development of motor skills.
Bone development is equally impaired and serious damage can be caused to the femur, tibia and feet. Later in life, the individual will experience hip, knee and feet problems (flat feet).
There are also assertions that this posture will affect normal visceral functions like bowels and breathing, due to the weakness of the back and abdominal muscles.
The reality is that W seat can cause orthopaedic problems, delay development of postural control and stability, and delay development of refined motor skills. For these reasons, its use is strongly discouraged.
The most effective way to prevent a problem with W-sitting is to stop it from becoming a habit it the first place. Anticipate and catch it before the child even learns to W-sit. Children should be placed and taught to assume alternative sitting positions.
If a child discovers W-sitting anyway, help him to move to another sitting position, or say: “Fix your legs.” It’s very important to be consistent.
When playing with a child on the floor, hold his/her knees and feet together when kneeling or creeping on hands and knees. It will be impossible to get into a W-position from there. The child will either sit to one side, or sit back on his feet; he can then be helped to sit over to one side from there (try to encourage sitting over both the right and left sides).
These patterns demand a certain amount of trunk rotation and lateral weight shift and should fit with a child’s developmental goals.
If a child is unable to sit alone in any position other than a W, talk with a therapist about supportive seating or alternative positions such as prone and side-lying. Tailor sitting against the couch may be one alternative; a small table and chair is another.