Poor body posture is a very frequent problem in modern days: forward head posture, rounded shoulders, the appearance of a little hump and of a belly fat, even if you are really young and skinny. From sedentary life to excessive use of mobile phone, from being seated most of the day to psychological reflexes, many theories have been put forward trying to explain the reasons of such a catastrophic spread in our current society. However, the real underlying cause of our posture problems is rarely mentioned: a poor craniofacial development! Read through and you will be surprised of how this problem and its consequences are severely misunderstood.
Poor body posture has recently increased among civilized societies, with people looking to treat this disorder in may ways due to its unpleasant aesthetic. However, remember that beauty is health: if you do not like your body posture, then probably your health is at risk! Forward head posture is a failure of the head to align with the vertical axis of the body: for every centimeter that the head is held forward (rather than balanced properly over the body), it gains about 2 kg of weight, with muscles of the back and neck that have to work much harder to counteract this misalignment (Figure 1) . Being forward head posture chronic, these muscles are put under excessive stress, causing reduced neck mobility , neck pain [3,4], migraine  and tension-type headache .
But where does forward head posture originate from? Many theories and associations have been put forward, with many different treatments proposed to improve this condition. However, we rarely hear the consequences that a poor craniofacial development can have on our body. Due to implications of our modern lifestyle, we are assisting to a down siding of the maxilla. Bones remodel according to force stimuli [7,8], that in case of the maxilla are coming primarily from the tongue and teeth in contact (through masseter muscles). When these forces are missing the maxilla drops down and back, reducing the eye support, flattening the cheekbones, narrowing the nasal airway, lengthening the mid facial third, and lowering the palate, which narrows and create malocclusion as a consequence (Figure 2) .
Position of the mandible directly depends on the maxilla, so when the maxilla grows down and backward, the mandible swings back. This causes TMJ problems, reduces the airways (including the pharynx, with breathing problems) and the head tilts forward in a forward head posture (Figure 3) [11,12,13]. The pharynx also serves as a resonating chamber for the voice, meaning that its restriction by poor craniofacial development can lead to voice disorders .
To better understand these mechanisms, try to do a simple exercise. Extend your head forward (Figure 4, on the left). In a very simplistic way, this mimic what happens with a forward growth of the maxilla. Notice that in this position, the natural tendency of the head is to move backward to align with the spine. Now do the exact opposite, flexing your head in what is called chin tuck (Figure 4, on the right). You will notice that in this case your head wants to move forward. This is exactly what happens when the maxilla grows vertically, pushing back the mandible and causing forward head posture.
Mouth breathers are those mainly affected by a poor craniofacial development. Indeed, breathing through the mouth implies individuals to keep their mouth open and the tongue in a lower posture. In this way the maxilla has only one force acting on it: the force of gravity. This remodels the maxilla vertically, pushing back the mandible and increasing mandibular inclination. The body then compensates with forward head posture [15,16,17,18]. Being the cervical column and craniofacial development strictly associated, their relationship with the hyoid bone changes as well (Figure 5) [19,20]. This has been correlated with asthma , sleep apnoea  and hypertrophic tonsils . Probably we should also start investigating what happens to the thyroid in these situation, because this environment probably does not allow this gland to work properly. Never questioned where all the modern thyroid problems may arise? Hoarseness, voice fatigue, or voice weakness that has been reported in patients with hypothyroidism may give a clue [24,25].
Every moment our body has to fight an invisible force to keep us upright: the force of gravity. No motions occur when our body finds the perfect balance and the equilibrium of forces to counteract the pull of gravity . This means that a forward head posture has consequences on the entire body, since the center of gravity is shifted. Firstly, the kyphotic curve increases, causing also rounded shoulders . Then, to compensate for the upper body shift, the pelvis tilts forward, increasing the lordotic curve and with consequences until the feet . This is how our body finds the center of gravity in case of forward head posture.
Body misalignment and abnormal myofascial tension deteriorate body’s health: in our body we have blood vessels, nerves, glands, organs that can be compressed by either muscles that are overtightened or by bones and vertebrae misalignment. Think for example about large blood vessels going to the brain that can be compressed by neck muscle tension [29,30], arteries that can be compressed by vertebral rotation [31,32,33], the spinal cord that can be compressed by vertebral dislocation or subluxation , lungs that have decreased capacity with an increased kyphosis [35,36], or about duodenum compression as a consequences of increasing lordosis or scoliosis . It is not a case if greater spinal inclination is linked to future dependence in activities of daily living , lower life satisfaction  and greater mortality  among older adults.
Everything matters, even rounded shoulders! A protracted shoulder increases strain on the various nerves passing through the shoulder region, especially the median nerve that then passes through the carpal tunnel . Carpal tunnel syndrome is the disability that results from the median nerve being pressed or squeezed, causing numbness, tingling, or burning sensations in the thumb and fingers, with pain in the wrists or hands, loss of grip strength and loss of manual dexterity. Current medicine is not able the explain the etiology of this syndrome, but did you know that carpal tunnel syndrome is associated with forward head posture  and hypothyroidism ? There is always a reason for everything and the causes of certain pain can derive from other far anatomical locations. So, do not neglect the importance of a holistic approach in understanding our body and probably you will understand the importance of craniofacial development.
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 Forward Head Posture, by Chiropractic Resource Organization
 Maxilla, single most important bone in the body?, by Claiming Power
 Neck pain, by Kinetic Edge Physical Therapy