By Dr. Vic Weatherall
Posture is essentially the position of the body in space, the relationship of the body parts—head, trunk, and limbs—to each other. Changes in posture occur when any part of the body is moved.
Posture also communicates nonverbal body language, reflecting self-esteem and mental attitude.
Optimal or ideal posture is the state of muscular and skeletal balance that protects the supporting structures of the body against injury or progressive deformity, whether at work or rest. It involves the positioning of the joints to provide minimum stress on the body. Conversely, faulty posture increases stress on the joints.
Increased stress can be compensated for by strong muscles, but if they are weak or the joints lack mobility or are too mobile, joint wear and modification can occur. Damage and changes to the surrounding tissues can also occur.
Posture involves the chain-link concept of body mechanics in which problems anywhere along the body chain can lead to problems above or below that point. Examples:
- Low back or knee pain can arise from pelvic joint disorders.
- Headaches, eyestrain, and neck and upper back pain can be caused by the head being too far forward or rearward.
The effects of posture can be far reaching, involving respiratory, digestive, and circulatory systems as well as the musculoskeletal system. But how is poor or faulty posture developed?
Causes of poor posture
The causes of faulty posture can be divided into two categories: positional and structural.
Structural causes are basically permanent anatomical deformities that may not amenable to correction by conservative treatments. However, some leg length inequalities and some ankle and foot issues can be corrected conservatively.
Positional causes of poor posture include
- poor postural habit—for whatever reason, the individual does not maintain a correct posture
- psychological factors, especially self-esteem
- normal developmental and degenerative processes
- pain leading to muscle guarding and avoidance postures
- muscle imbalance, spasm, or contracture
- joint hypermobility or hypomobility
- respiratory conditions
- general weakness
- excess weight
- loss of proprioception—the ability to perceive the position of your body
- over reliance on passive support from a non-ergonomic chair
Physiology of posture
Posture control involves static and phasic reflex activities:
- Static reflexes involve sustained contraction of the musculature.
- Dynamic short-term phasic reflexes involve transient movements.
Both types of reflex are integrated at various levels in the central nervous system (CNS) from the spinal cord to the cerebral cortex and are largely effected through extrapyramidal motor pathways.
Postural reflex patterns from reflexes, such as the stretch and flexion (withdrawal) reflex pathways, result in a coordination of many joint movements and combinations of muscle actions:
- These involve the contraction of prime movers, synergists, and stabilizers, along with the necessary relaxation of antagonists.
- These muscles are regulated for contraction intensity, speed, duration, and sequential changes in activity.
The integrative pattern of posture is predominantly automatic and unconscious, resulting from the incessant shifting of weight (postural sway).
Postural corrections are continuously mediated by spinal reflexes. Posture is further mediated by the visual, labyrinthine, neck-righting reflexes, and by the interplay of joint reflexes.
While the control of posture is primarily controlled by various reflex mechanisms, there is also extensive input from the higher centers of the nervous system. Therefore, posture to some extent can be relearned (corrected) just as it was learned in the first place.
Correcting postural faults
Postural faults must be accurately analyzed before they can be effectively corrected.
Examination should include the following:
- observation of the patient as they sit and move about
- spinal alignment
- if appropriate: measurement or estimation of the deviation from ideally erect postures using plumb lines, inclinometry, and posture guides —done in three or all four views
- limb length and girth measurements
- flexibility tests and joint mobility tests
- muscle length and strength tests
The importance of muscle testing to postural analysis cannot be over-emphasized. Much of the specific therapy in posture correction relies directly on muscle tightness and weakness found during examination.
Conventional corrective therapies
Five main modalities are employed in the conventional treatment of faulty body mechanics and hence postural faults: heat; massage; stretching; strengthening exercises; and supportive measures to treat ligaments, bones, and nerves.
Shortened agonist muscles must be stretched before the antagonist muscles can be optimally exercised to increase their strength, or vice versa. Depending on the condition, manipulation may also be required to release an accompanying joint fixation. Therefore, manipulation should be added to the list of posture correction therapies.
“Back schools” educate patients (students) in back health care and body mechanics in daily living, the workplace, and during perisurgical care. These schools use props and obstacles for activity evaluation purposes and to teach proper posture and body mechanics.
Custom foot orthotics
Custom foot orthotics are often used to correct structural postural faults that underlie many back lower limb problems. They help to correct issues such as overpronation and oversupination. They can also act as vehicles for heel lifts to correct leg length inequalities.
In extreme cases, such as developmental or chronic anatomical abnormalities, or stabilization following trauma or deteriorating conditions during development, orthotic devices are employed to correct and support posture. An orthosis is an external appliance worn to restrict or assist motion or to transfer the load from one area to another.
There are many types of orthoses and they will not be dealt with in detail here; however, scoliosis orthoses are of special interest to chiropractors. Children and adolescents with thoracic, thoracolumbar, or lumbar scoliosis or kyphoses may be fitted with an orthosis, such as the Milwaukee brace, to apply forces to realign the vertebral column and thoracic cage. Orthoses such as the Milwaukee brace provide stabilizing effects while being worn and most importantly they prevent the curve from increasing beyond its original contour.
It is interesting to note that some authors believe that the effectiveness of a brace, such as the Milwaukee brace, could depend on its ability to signal spinal curvature through increased discomfort at the pressure points, thereby creating a motivational effect for patients to correct their posture.
Applied biofeedback is a group of therapeutic procedures that use electronic or electromechanical instruments to accurately measure, process, and feed back to patients information, with reinforcing properties, about their normal and abnormal neuromuscular and anatomic activity. This information usually takes the form of analog or binary auditory or visual feedback signals, or both.
Biofeedback helps patients develop greater awareness and voluntary control over their physiological process that are otherwise outside awareness or under less voluntary control. The patient first achieves awareness and control using the measuring device to manipulate the external signal and then uses internal psychological cues to do the same.
Examples of postural defects treated using biofeedback include adolescent idiopathic scoliosis, torticolis, and rounding of the back or slouching (functional thoracic kyphosis) due to poor posture.
There are a variety of biofeedback devices and smartphone applications readily available. However, the functionality of these tools is often limited by where they are placed on the body and their how effectively they measure change.
- Gatterman MI. Chiropractic Management of Spine Related Disorders. Ed. Gatterman MI et al. Baltimore: Williams and Wilkins, 1990. 413.
- Panzer DM, Fechtel SG, and Gatterman MI. “Postural Complex.” Chiropractic Management of Spine Related Disorders. Ed. Gatterman MI et al. Baltimore: Williams and Wilkins, 1990. 256-268.
- Magee DJ. Orthopedic Physical Assessment. 2nd ed. Philadelphia: W.B. Saunders, 1992. 579-582.
- Travell JG and Simons DG. Myofascial Pain and Dysfunction: The Trigger Point Manual. Baltimore: Williams & Wilkins, 1983. 112-113.
- Azrin N, Rubin H, O’Brien F, Ayllon T, and Roll D. Behavioral Engineering: Postural Control by a Portable Operant Apparatus. Journal of Applied Behavior Analysis. 1 (Summer 1968): 99-108.
- Ganong WF. Review of Medical Physiology. 11th ed. Los Altos: Lange Medical, 1983. 160
- Fardon DF. “Back School.” Rehabilitation of the Spine: Science and Practice. Ed. Hochschuler SH and Richard GG. St. Louis: Mosby-Year Book, 1993. 725 and 731.
- Edelstein JE. Orthotic Assessment and Management. Physical Rehabilitation: Assessment and Treatment. Ed. O’Sullivan SR and Schmitz TJ. Philadelphia: F.A. Davis, 1994. 655 and 671.
- Dworkin B and Miller NE et al. Behavioral Method for the Treatment of Idiopathic Scoliosis. Proceedings of the National Academy of Sciences of the United States of America. 82 (Apr. 1985): 2493-2497.
- Olson RP. “Definitions of Biofeedback.” Biofeedback: A Practitioners Guide. Ed. Schwartz MS and associates. New York: The Guilford Press, 1987. 35.