Only in the last few years has “i-phone neck” or “text neck” been considered a diagnosis for neck and spinal pain originating from too much time spent in a prolonged, poor posture, staring into the luminous screen of a smart phone.
I would probably say 80% of a typical day involves attending to postural spinal pain, usually from prolonged positions, mostly driving, sitting at a desk or utilising an iphone, ipad or similar.
So what is “posture”?
A recent ergonomic textbook states that posture is defined as the “average orientation of the body parts over time” or simply put, a position or alignment of body parts. As physiotherapists we are generally concerned about the angles between body parts, the distribution of weight between body parts, the length of time patients are in certain postures and the effects of these postures on certain individuals.
All descriptions of posture imply that posture is an active process, rather than a static one. We may remain in relatively static postures for long periods but all of these activities are characterised by intermittent changes in posture. ‘Posture cannot be separated from movement, but should be regarded as temporarily arrested movement as it is in a constant state of change, as anyone trying to stay still for any length of time will know’ (Trew and Everett 2001).
Aging can be associated with more fixed postures, such as loss of lumbar extension and exaggerated cervico-thoracic kyphosis because of spondylotic changes or osteoporosis. Inflammatory joint pathologies, such as ankylosing spondylitis and rheumatoid arthritis, can also produce dramatically reduced movement.
Is there an ideal posture?
There has always been controversy over the “ideal” posture. Some studies suggest that the lumbar spine should be slightly flexed when sitting (Adams et al. 2002); whereas others suggest that a more lordotic posture is best (Harrison et al. 1999; Pynt et al. 2001; 2008). Good posture in the cervical spine is defined as ears aligned with the shoulders and the shoulder blades retracted. (Hansraj, MD 2015)
So what does “poor posture” do to our bodies?
Bending and sitting is associated with flexion of the lumbar, thoracic and lower cervical spine. Different postures alter muscle activity; during standing back muscles show slight, intermittent or no activity, with activity influenced by the position of the spine in reference to the line of gravity. The more off the centre of gravity the more contra-lateral muscle groups will need to work to maintain control. During sitting, muscle activity is minimal so loads tend to be transferred to local soft tissues.
With flexion of the cervical, thoracic and lumbar spine the intervertebral disc is compressed anteriorly, which causes a posterior displacement of the nucleus pulposus, an increase in intra-discal pressure, there is even distribution of stress within the disc, and increased supply of metabolites to the disc. The spinal and vertebral canals are widened, the spinal cord is tensioned, and the load on the zygapophyseal joints is reduced with flexion.
More specifically in the cervical spine, a study by Kenneth K. Hansraj, the Chief of Spinal Surgery at New York Spine Surgery and Rehabilitation Medicine has discovered that the weight seen by the spine increases when flexing the neck at varying degrees. An adult head weighs 4.5-5 kilograms in the neutral position. As the head tilts forward the forces seen by the neck surge to 12 kilograms at 15 degrees, 18 kilograms at 30 degrees, 22 kilograms at 45 degrees and 27 kilograms at 60 degrees!
What exactly happens to our muscles and why do we experience the pain?
Skeletal muscle is made up of two types of muscle fibres – static (often called ‘slow twitch’) and phasic (often called ‘fast twitch’). Generally, static muscle fibres are found in the deeper muscle layers. They help us to maintain posture without too much effort and contribute to balance by ‘sensing’ our position and relaying this information to the brain. Phasic muscle fibres are used for movement and activity. Static fibres burn energy slowly and can keep working for a long time without tiring. However, phasic fibres quickly fatigue. Poor posture causes muscle fatigue because it calls on the phasic fibres instead of static fibres to maintain the body’s position.
Over time, poor posture that demands support from phasic fibres causes the deeper supporting muscles to atrophy from lack of use. Weak, unused muscles tend to tighten and this shortening of muscle length can compress spinal bones and worsen posture.
The deeper layers of muscle are concerned with ‘sensing’ our position in space and relaying this information to the brain. If this function is taken over by phasic muscles, the brain gets an incorrect picture. The brain assumes that the body needs to be propped up to counteract the effects of gravity, so it triggers further muscle contraction. This adds to the general fatigue, pain and headaches felt by the person with poor posture.
What can we do about this?
Physiotherapists can help by addressing the following –
Postural education and retraining
Exercises to improve strength, posture and/or flexibility
Soft and deep tissue massage
Ergonomic work station set up
Activity specific advice
People spend an average of two to four hours a day with their heads tilted over reading and texting on their smart phones and devices. Cumulatively this is 700 to 1400 hours a year of excess stresses seen about the cervical spine.
Dale Tanner, a workplace-related injuries and musculoskeletal disorders specialist of 20 years and chairman of the Workplace Wellness Conference puts it bluntly. “Sitting is the new smoking,” he says. “Seventy per cent of Australians are deemed to be sedentary or insufficiently active. That’s 16.8 million people. Of those, around 3.9 million will develop breast and colon cancers, 4.5 million will develop type 2 diabetes and over 5 million will suffer coronary heart disease. These illnesses will develop purely as a consequence of inadequate levels of physical activity … and corporate Australia is trying to do something about it.”
The improvements in technology are vastly increasing and unfortunately, so are the numbers of people presenting to physiotherapy with ailments related to these improvements. With appropriate preventative education and exercise, these numbers do not have to continue to rise. If you are one of those people, and 77% of you are, that sit at a desk for at least eight to nine hours a day, and are experiencing postural pain, come and chat to one of our physiotherapists today!
Bridger RS. 2003. Introduction to Ergonomics. 2nd ed. London: Taylor & Francis. p. 33.
Trew M, Everett T. 2001. Human Movement. 4th ed. Edinburgh: Churchill Livingstone. p. 225-240.
Bland JH. 1994. Disorders of the Cervical Spine. Diagnosis and Medical Management. 2nd ed. Philadelphia: W.B. Saunders Company. p. 71-113.
Bogduk N. 1997. Clinical Anatomy of the Lumbar Spine and Sacrum. 3rd ed. New York: Churchill Livingstone. p. 118.
Harvard Editorial Board: How to soothe a sore neck. The essentials are icing and heat, gentle therapeutic exercise,
and good posture. Harvard Mens Health Watch 2014;18(11):5.
South Perth Physiotherapy