Posture Research

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Posture Research - 2

2.1 Martin-Du Pan R. et al. The role of body position and gravity in the symptoms and treatment of various medical diseases. Swiss Med Wkly 2004; 134:543-551.

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SELECTED QUOTATIONS:
"In conclusion, postural medicine deals with the different effects of gravity on the human body and with the physiopathological changes resulting from various body positions." "Physiological adaptations mainly due to the effect of gravity occur during changes of position and can influence the symptoms of various diseases involving not only the circulatory system but also other systems (respiratory, digestive, osteoarticular etc)." "When caring for our patients, we should not forget the utility and side effects of the omnipresent force, gravity."

2.2 Stokes I. et al. Influence of the Hamstring Muscles on Lumbar Spine Curvature in Sitting. Spine 1980; Vol 5 No. 6, 525-528.

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COMMENTS:

The purpose of the study was to investigate if individuals with short or tight hamstrings would have abnormal tilting of the pelvis in some seated postures, with greater flattening or reversal of the lumbar lordosis (lower back arch). The seated posture is different from standing in that the hips are flexed and the pelvis is simultaneously tilted to bring the ischial tuberosities (the bones you sit on) into a weight-bearing position. Tilting the pelvis backward reduces the lumbar spine forward arch. Greater backward tilting of the pelvis increases posterior ligament tensions, posterior muscle activity, and, hence, compression on the spine. Thirty-eight healthy adults were studied. Individuals with nearly 90 degrees forward hip flexion in the standing toe-touch test were able to sit with variable knee positions (i.e. variable hamstring tension) with minimal change in spine posture. Individuals with more restricted forward hip flexion in the standing toe-touch test were not able to sit with more extended knee positions (i.e. leg straightening with greater hamstring tension) without flattening or reversing their lumbar spine forward arch. The authors concluded that straightening or reversal of the lumbar lordosis on sitting is related to hamstring tightness. This same correlation between limited lumbar / pelvic range of motion, decreased lumbar lordosis and tight hamstrings was also found in a study of children with cerebral palsy (Spine 2000; Vol 25 No 2, 211-213), and in a study of patients with Scheuermann Kyphosis (Spine 2003; Vol 28 No 19, 2252-2259).

2.3 Lennon J., Shealy C., Cady R., Matta W., Cox R., Simpson W. Postural and Respiratory Modulation of Autonomic Function, Pain, and Health. AJPM 1994; 4:36-39.

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The following are excerpts from this scholarly paper:

"Despite considerable evidence that posture affects physiology and function, the significant influence of posture on health is not addressed by most physicians."

"Observations of the striking influence of postural mechanics on function and symptomatology have led to our hypothesis that posture affects and moderates every physiologic function from breathing to hormonal production. Spinal pain, headache, mood, blood pressure, pulse, and lung capacity are among the functions most easily influenced by posture."

"The most significant influences of posture are upon respiration, oxygenation, and sympathetic function. Ultimately, it appears that homeostasis and autonomic regulation are intimately connected with posture."

"For many years physiologists have shown that the position of the head on the neck is vital because it governs all postural reflexes. If the head is misaligned, other parts of the body move in and out of line to maintain balance and thus energy is expended to counteract the effects of gravity."

"At the Shealy Institute, clinicians have consistently observed striking postural abnormalities in virtually every patient with back pain, headache, or depression."