Important clinical concepts about posture

What is ideal posture?

Our posture is how we hold our bodies upright. To do that we rely on a series of reflexes that control our muscles so that we can support ourselves against the force of gravity. Ideally, our posture should be:

efficient – doesn't require a lot of energy
effective – provides a secure foundation so we can freely move, and
safe – minimises the load and potential for tissue injury.

While there have been many ways at looking at posture; biomechanical, therapeutic (chiropractors, osteopaths and physiotherapists), movement based (alexander technique, tai chi and yoga) – they seem to share a number of common themes:

  • The head appears balanced lightly on the top of the spine,
  • The spine becomes longer,
  • The muscle and joints are able to move freely and with a minimum of tension,
  • The joints are correctly aligned for proper support and load bearing,
  • and
  • The normal body reflexes can work as nature intended them.

When considering posture, it is also important to consider how people move. This important relationship was best described by Sherrington (1906), '…posture follows movement like a shadow…'.


Why does poor posture lead to pain?

There are many possible reasons why poor or faulty posture may cause pain, discomfort and contribute to other health problems.

These include :

Posture – Changes Alignment & Weight Bearing

Certain areas of the body are designed to take load – discs and the broad joint surfaces like the hips, knees and ankles. Other areas, like the bony facet joints in the spine, are designed to guide movement and aren't suited for prolonged weight bearing. Faulty posture puts more load on the wrong places.

For instance, a slouching head forward posture doubles the load on the cervical spine and also causes the shoulders to roll forward making the shoulder tendons more vulnerable to wear and tear. Poor posture and body mechanics may cause early disc degeneration and osteoarthritis.

Posture – Influences Breathing

Posture influences a person's ability to breath. The head forward posture encourages shallow breathing because the ribs and diaphragm can no longer move properly. As a result, the accessory respiratory muscles connecting from the neck to the upper ribs – normally used as a safety reserve during vigorous exercise – become activated.

This creates abnormal tension in the muscles and soft tissues, and what normally would be relaxed becomes tight and what would normally tighten and relax becomes inactive and weak.

A faulty breathing pattern becomes established and the ribcage becomes gradually drawn upwards so that the muscle activity of the diaphragm changes. This in turn changes the degree of intra-abdominal pressure which stabilizes the lumbar spine.

Posture – Changes Muscle Tissue

Poor posture can change muscle tissue and cause tightness, pain and tenderness, as well as weakness. Characteristic symptoms may be present according to which muscles are involved (i.e. trigger points, scalene syndrome and pect minor syndrome).

Posture – Effects How Muscles Work

Many rehabilitation specialists and neurologists believe that when injured our body adopts certain movement patterns where some muscles become overactive and tight while others become inactive and loose. These patterns are related to the normal development of motor control. What has been found is that when injured the earlier more primative movement patterns dominate while the later more complicated activities become inhibited.

An extreme example of this feature is a person who has had a stroke – there is a well recognized pattern of certain muscles becoming tight while other muscles become weak. The characteristic pattern for postural dysfunction in the neck and upper back has been called an Upper Crossed Syndrome. There is a classic pattern of chin forward posture, tight trapezii muscles and weak deep neck flexor muscles.

Posture – Influences The Nervous System

Faulty posture can trap or irritate nerves. Local mechanical irritation can cause nerves to fire inappropriately – creating an – Abnormal Impulse Generating Site – in the same way rubbing the insulation off an electrical cable may cause a short circuit. For example, slouching may cause pain and a burning sensation in the middle back – Notalgia paraesthetica -because the nerves travel along a curved path through the muscles. If you change the length and alignment of the muscles, the nearby nerves may become vulnerable to physical stretch and become irritated.

Poor posture is a very common underlying cause of spinal dysfunction. The spine has a rich nerve supply and poor function can give characteristic symptoms: disturbances in the upper cervical spine may contribute to headaches and balance disorders, disturbances in the upper back area can cause headaches, chest discomfort and pins and needles in the hands i.e. T4 syndrome.

One aspect of the nervous system that is often forgotten is that the brain relies on high quality information (sensation) coming back from the the muscles and joints of the body. With poor posture the spinal joints become stiff, especially in the upper back region, and begin to provid 'less 'input' back to the brain. With less input the brain can gradually lose awareness of that area and begins to think of that area as a solid block rather than individual segments. This change of awareness leads to a further lose of movement.

Posture – Causes Tissue Creep

Poor posture can lead to tissue creep. That is when the collagen fibres in the inner fabric of ligaments stretch and deform – similar to how plastic gives way under stress. Once this change has happened it difficult for the tissues to return to their normal length. Tissue creep may occur after long or repeated loading – it can start after as little as 15 minutes of slouching. This commonly effects people who spend hours working in the one position. Children who play computer games for long periods are at risk of tissue creep.


Approaches of care

Many people may require professional assistance to help manage or correct a postural problem. While a Posturepole™ may be helpful it does not replace the need for a proper clinical assessment by an appropriately experienced registered health professional. In particular children and teenagers who have poor posture or a spinal curvature should seek professional advice. There are many approaches to postural problems. These might include: exercise, postural and ergonomic advice, spinal manipulation and soft tissue massage and mobilization.

Further reading
Any health professional wanting to learn and understand more about posture and the consequences of poor posture on the health of the neuro-musculo-skeletal system, may benefit from reading the following texts.

The Sensitive Nervous System
Butler D
ISBN: 064640251X
David Butler has prepared an excellent book for practitioners involved in movement based therapies. Brings together the latest neurological concepts with the practical hands-on skills of a patient focused clinician.

Muscles and Cervicogenic Pain Syndromes
Janda V
Included in Grant R. �Physical Therapy Of The Cervical And Thoracic Spine�
ISBN: 0443085072
Anyone who wants to understand posture and the vital role muscles play in pain and dysfunction should study the writings by the late Czech neurologist, Vladimir Janda.

The Prague School of Rehabilitation and Dynamic Neuromuscular Stabilization
Kolar P
The 'Prague School' was established by some of the most influential neurologists and manual medicine experts of the 20th Century: Professors' Vaclav, Vojta, Lewit, Janda and Vele. These individuals mentored and guided Professor Pavel Kolar to develop a new and exciting rehabilitation approach called Dynamic Neuromuscular Stabilization.

Rehabilitation Of The Spine 2nd Edition – A Practitioners Manual
Liebenson C
ISBN: 0781729971
Craig Libenson's text provides a comprehensive manual on spinal rehabilitation and has drawn together the teachings of many leaders in the field of manual therapy. Focuses on the practical management of spinal related disorders. Has an excellent DVD.

Manipulative Therapy In Rehabilitation Of The Locomotor System
Lewit K
ISBN: 0750629649
Written by Proffessor Karel Lewit, one of the founders of the Czech approach to manual therapy and rehabilitation. Considered to be a classic textbook in modern manual medicine.

Myofascial Pain and Dysfunction: The Trigger Point Manual
Travell J, Simons D, et al
ISBN: 0683307711
Janet Travell and David Simons were pioneers in myofascial pain and treatment. Their classic textbook provides clear descriptions about how to indentify and manage these common causes of pain and dysfunction.