Posture can be defined as the position of the body in any environment or mode. Some examples of specific postures are sitting, standing, walking, or leaning forward. Posture is based on the position of the spine and all the joints in the musculoskeletal system. Postural evaluation or analysis consists of evaluating a patient's posture through a series of appropriate tests and measurements. It is part of the branch of physical therapy called kinesiology, which includes the study of the anatomy and physiology of body movement.
Good or normal posture is defined as an imaginary straight line that connects the earlobe, cervical vertebrae, acromion (bony outgrowth on the shoulder blade), lumbar vertebrae, and a set of points behind the hip and slightly in front of the knee and ankle. In an actual postural evaluation, the patient may be asked to stand by a vertical plumb line so that the examiner can visualize any deviations from normal alignment.
Good posture in humans is the end product of a complex combination of mechanical, neurological, and psychological factors, including muscular strength and flexibility, vision, touch, balance, self-esteem, kinesthetic (a sense of the location and movement of muscles and joints) awareness, and a properly functioning vestibular (inner ear) system. Because of the number of bidy parts and functions involved in good posture, a postural evaluation may serve a variety of purposes:
- As part of the musculoskeletal assessment of a balance evaluation. Postural abnormalities frequently affect an elderly person's sense of balance and his or her ability to react quickly to loss of balance.
- As a step in the differential diagnosis of chronic pain syndromes. Chronic neck and back pain in particular often result from poor posture, which causes muscles to contract, changes the amount of blood flow to the spine, and leads to deformation of the connective tissues in the spine and neck area.
- As part of a physical examination in sports medicine. Deviations from normal posture increase the risk of certain types of athletic injuries, and may interfere with athletic performance.
- In the evaluation of work-related postural problems and repetitive stress injuries (RSI). Some physical therapists now visit work places in order to assess the physical demands of certain jobs—especially jobs that require sitting at desks in front of computers for long periods. These assessments are sometimes called ergonomic evaluations, which means that the design of equipment and other physical features of the workplace is coordinated with the physical requirements of the workers.
Postural evaluation is noninvasive and should not cause the patient physical discomfort under normal circumstances. Care should be taken, however, to perform the evaluation in an appropriate examination room to protect the patient's modesty. The room should be kept at a comfortable temperature.
Postural evaluation typically begins with a visual assessment of the patient's posture while he or she is standing by a vertical plumb line. The person's posture is then scored according to check lists for the back view and the side view. Deviations from good posture are rated according to severity, in which a slight deviation is scored as 1 point, a moderate deviation as 2, and a severe deviation as 3 points. The total number of points from both back and side views is then calculated. A score of 12 points or higher is considered poor posture. Some therapists prefer to use posture photographs for a postural evaluation, while other practitioners may order x rays, on the grounds that these imaging modalities yield more accurate results than simple viusal examination.
Visual assessment of posture also includes the clinician's careful visual observation of the patient's positioning during walking, sitting, and weight transfers.
Manual muscle testing is an important part of postural analysis. The clinician uses his or her hands to evaluate the various muscles for atrophy (wasting away from disuse), misalignment, overstretching, or constriction and shortening. Manual testing also allows the clinician to determine the extent as well as the presence of muscular imbalance.
Accurate evaluation of patients with postural dysfunction requires careful history-taking. This includes family and social history as well as medical history. In most cases changes in posture are due to such anomalies as excessive weight gain, poor postural habits, traumatic injuries, uneven development of the musculature, or congenital defects. A family history may yield information about hereditary disorders that affect posture as well as family members' attitudes toward the patient. In some cases, people develop poor posture in response to physical or emotional abuse.
An accurate postural evaluation provides the physical therapist with necessary information in devising a treatment plan. The goal of rehabilitation is to isolate the cause(s) of postural abnormalities and provide appropriate treatment through postural correction exercises and patient education. Other treatments can include such modalities as heat, ice, and massage; flexibility exercises; strengthening programs; and cardiovascular conditioning.
Acromion— A bony prominence on the shoulder blade that articulates with the clavicle, forming the acromioclavicular (AC) joint.
Atrophy— The wasting away of muscle tissue from disuse.
Kinesiology— The branch of physical therapy that deals with the anatomy and physiology of body movement.
Osteoarthritis— A degenerative disorder of the cartilage and bone in the joints.
Osteoporosis— A condition characterized by decrease in bone mass and density, and enlargement of bone spaces.
Health care team roles
Postural evaluations may be performed by physical therapists, physicians, nurses, and chiropractors. It is important that physicians—especially pediatricians—nurses, and other allied health professionals routinely evaluate patients' posture in an effort to minimize further complications of various diseases and disorders. Most health care facilities have screening clinics that offer postural assessment free of charge. It is also imperative that individuals with spinal osteoarthritis, osteoporosis, Marfan's syndrome, and other conditions that affect the spine be properly educated on the importance of good posture. The elderly and others who may have developed balance problems should have their posture evaluated as part of an overall balance evaluation.
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Lehmkuhl, L. D., and L. K. Smith. Brunnstrom's Clinical Kinesiology. Philadelphia: F.A. Davis Co., 1996.
Magee, D. J. Orthopedic Physical Assessment. Philadelphia: W. B. Saunders Co., 1997.
National Rehabilitation Information Center and ABLEDATA (database). 8455 Colesville Road, Suite 935, Silver Spring, MD 20910. (800) 346-2742 or (800) 227-0216.