In order to build a stronger and healthier neck, one must understand 4 crucial structures of the cervicothoracic anatomy, as is described in the image above. The cross indicates 4 muscle groups, each located in the 1)upper frontal, 2)lower frontal, 3)upper rear and 4)lower rear quadrants acting as tension cords that anchors and pulls from the base of the neck to maintain an upright posture (base of the neck). Thus, it is given the pictorial name to the anatomical junction, the "upper-cross".
Starting with 1)upper frontal quadrant, we have the "deep neck flexor" muscles that, when contracted, will pull the chin in-wards towards the neck and keeping the head upright. This group of muscles aren't particularly strong. In fact, they are mostly inhibited (barely used) in the typical office-type worker due to work posture and also as a consequence of modern life.
The 3)upper rear quadrant muscles (neck stabilizer muscles) also contribute to help the person look up and keep an upright posture. However, if one is suffering from a lack of tensional strength of the 1)deep neck flexors, these stabilizer muscles will have to pick up all the slack of keeping the head upright. I.E. compensational behaviour. Hence, the often sore and over-fatigued shoulder muscles.
2)Lower front quandrant muscles indicate the pectoralis major and minor muscles - very strong muscles that bring the shoulder forward, thereby 'rounding' the shoulders. These muscles are often over-tight like the 3)neck stabilizer; again also due to prolonged sitting postures that require both arms to be in front the body (IE. any writing, reading or computer-use). Overactive pectoralis muscles will counteract and inhibit the 4)lower rear quadrant muscles: the mid/lower trapezius & serratus anterior. When this occurs, the result is 'winging of the scapula' (I.E. the shoulder blades being further apart from each other) and hyper-kyphosis (I.E. increased curvature of the upper back).
Essentially, with upper cross syndrome, the sitting posture and, most of the time, the resting posture of the subject will look something like this.
To counteract the effects of the upper cross syndrome isn't very difficult, at least in theory. A key factor in seeing good results is patient commitment and diligence to make gains on a consistent basis. The required treatment is to reduce tension in the hyperactive muscules: 2)neck stabilizers & 3)pectoralis muscles. This can be done by chiropractic adjustments to the anchor points of the levator scapulae and upper-trapezius muscles. Further adjustments may also be required at high compression points of the spine where the curvature is at an apex. Most commonly, they are the atlanto-occipital, cervicothoracic and T4 adjacent segments. So up to this point in therapy, half of the cross has received some attention, but the other half must be reinforced. This can be achieved by activating the 1)deep neck flexors & 4)lower trapezius & serratus anterior muscles via postural correction, stability exercises and strength training routines described in 'how to build a stronger neck part 2'.