Kyphosis is a postural syndrome of the upper back and neck. Typically the upper back appears curved with rounded shoulders, the scapula (shoulder blades) are protracted (positioned further away from the spine) and the chin pokes forwards rather than being tucked in.
Cervical posture syndrome is sometimes also called upper crossed syndrome. This is due to the muscle imbalances that are present with this type of posture. For example, the pecs and posterior neck muscles are tight and the muscles of the upper back and deep neck flexors are weak. If you connect the two tight muscle groups and the two weakened muscle groups with two straight lines, they form a cross shape, giving the condition its name.
1) Keep the chin tucked in
2) Keep the shoulders relaxed, down and back
3) Sit with a curve in your low back (see picture) as this allows the pelvis to sit directly under the points of your shoulders so you sit on the bony points of your bottom.
4) Sit with your hips, knees and ankles at right angles, thighs level with knees.
1) Poke or jut chin forward
2) Hunch shoulders/Round shoulders
3) Sit with your spine in a 'C' shape (this puts your back under strain)
4) Sit with your knees higher than your hips (spine becomes 'C' shaped, knees can easily fall to one side leading to a twisted pelvis). Sit with your knees lower than your hips (bottom slips forward on the seat and knees knock together)