- Why do we do it? Is it all that important? Can it be changed?
Why do we do it? Is it all that important? Can it be changed?
<p>1Why do we do it?Is it all that important?Can it be changed? Postural Assessments 2Injury prevention?Pain reduction?Aesthetics?Performance? Why do we do it?3The importance of normal upright posture has been proposed since the early 1900s when it was described as a state of balance requiring minimal muscular effort to maintain.Posture 4Points of reference consisting of the lobe of the ear, the seventh cervical vertebra, the acromial process, the greater trochanter, just anterior to midline of the knee, and slightly anterior to the lateral malleolous which form a theoretical line around which the body is balanced in perfect skeletal alignment, yielding equal weight distribution and maximum joint stability .Ideal posture?5</p>
<p>6Unbalanced biomechanical joint stresses that result from muscle imbalance may lead to joint damage, setting up a vicious cycle of pain and inflammation. The structural inflammation then affects the neuromuscular system of the joint, creating further dysfunction. Eventually the body adapts the motor program for movement to compensate for the dysfunctionTrending theory 7Vicious Cycle8identification9</p>
<p>14Anterior tilt: Lower body cross syndrome A15Posterior Tilt: Lower body cross syndrome B 16Misalignments can impose excessive stress on the spine leading to degeneration/damage or dysfunction and eventually to painful back conditionsIn this model, the imbalances and symmetries increase the abnormal mechanical/physical stresses imposed on the musculoskeletal system. This may lead recurrent injury or the development chronic conditions through a gradual process of wear-and-tearSolid theory?Postural Structural Biomechanical Model Conclusions 17</p>
<p>NOT SO FAST!18Is B really caused by AIs pain and dysfunction really caused by poor posture How do these theories hold up?19Lets look at this again20Lumbar lordosis induced byThese muscle impairments lead to increased lumbar lordosis and might cause chronic low back pain. Imbalance: tightness with weakness LCS examination 21No significant differences in the degree of lumbar lordosis in subjects with and without short hamstrings. Lumbar lordosis and hamstring length 22No significant difference in the degree of lumbar lordosis and in the length of hip flexor muscles. Hip flexors23No association between the angle of pelvic inclination, the size of the lumbar lordosis and abdominal muscle strengthNo association between the length of abdominal muscles and the size of lumbar lordosis. Abdominal length and strength 24Pain changes movement but does posture change movement patterns?Movement patterns and postural changes 25200934,902 Danish twins 20-71 years oldNo meaningful differences in frequency in LBP between younger and older individuals, although greater joint degeneration changes are expected in older individuals. Joint degeneration?26In the biomechanical model the musculoskeletal system is seen as a precision engine where every system, organ and cell works in perfect harmony within itself and other body systems.All joints and body masses are in some anatomically ideal relation with one another. MECHANICAL MODEL 27</p>
<p>SOLID THEORY? 28Within the biological dimension the structure (spine) is capable of self repair and is able to adapt and change according to needs and demands. Our structure is within our awareness and highly in tune with our emotions. Biological model29The spine can undergo profound physical changes that are well tolerated without the development of a symptomatic condition. Biological reserve 30Multivariate analysis show that correcting posture may not be the answer to improving LBP improvements in posture lead to variable increases in shoulder ROM but intensity of pain is not affected. Subjects respond individually to the effects of posture change. Injury prevention/pain reduction?31How relevant is postural deviation? 32Some support to the belief that reducing the thoracic kyphosis can contribute to improving arm elevationNo studies that have looked at changing kyphosis in people with SIS to determine if it decreases pain. Kyphosis 33Estimated that 90 percent of the population has a leg length inequality with a mean of 5.2mmSignificant if magnitude reaches 20 mm. No correlation to LBPPerthes disease Leg length discrepancy 34Aesthetics </p>
<p>35Does static posture translate over to dynamic movement?Posture is structural strength is neuralIncreased ROM with postural corrections although this is variable </p>
<p>Performance 36No significant relationship between lumbar lordosis and isometric strength of the trunk flexors and extensors and hip flexors and extensors. Abdominal muscle strength not significantly associated with lumbar lordosis. 37Weak and lengthened agonist vs strong and tight antagonist proposed cause. So what would one do?Strengthening and stretching exercises have been prescribed according to deviation. Strengthening = shortening? Stretching = lengthening? Can it be changed? 38Does an increase in muscular strength allow a better posture to be held? If this were the case it would not be unreasonable to expect that individuals with poor posture had weak muscles; however this is not the general finding. Strength?39Back muscle length was not significantly associated with lumbar lordosis for men or women. Weakly associated with abdominal length not strengthLength? 40Exercise programs are insufficient in duration and frequency to induce adaptive changes in muscle-tendon length. 41In the context of postural-structural-biomechanical (PSB) factors, it is expected that tremendous forces, well above the daily physical stresses, would be required to reposition/adjust/correct any structural misalignments. These would have to be applied on a daily basis over several months or even years. A termination of treatment is likely to result in rapid reversal of PSB gains, unless the individual is able to self maintain them by specific exercise. The winner in the competition-in-adaptation, is ultimately the one most practiced, that is, the default PSB state/behavior of the individual 42Incidence of pain increased in subjects with more severe postural abnormalities However, posture is individual: a number of individuals with normal posture were found to have significant pain, whereas some individuals with more severe postural deviations in the TCS region were found to have minimal pain. Causality cannot be determined. Concessions 43</p>
<p>45Impairs mobility and increases risk of falls and fractures.a kyphosis angle greater than 40 degrees is defined as hyperkyphosis. Women with hyperkyphotic posture demonstrate difficulty rising from a chair repeatedly without using their arms. Age related hyperkyphosis 46Hyperkyphotic posture has been associated with increased mortality, with higher mortality rates associated with the severity of kyphosis. Reduced vital capacity is associated with hyperkyphosis, and severe hyperkyphosis is predictive of pulmonary death among community dwelling women. Women in the highest quartile of kyphosis were more likely to die of pulmonary death compared with those in the lower quartiles of kyphosis. 47Is it relevant? </p>