Brain-Based Solutions™ for Your Posture
The Human Ability to Stand Upright (Abridged)
Posture is simply the position of your body assumes when dealing with gravity. It makes no difference whether you are sitting, standing or lying down, your posture displays your body’s ability to perform in its environment.
Good posture does not just happen, it is a pre-programmed neurological display. The ability to stand, sit or lie down properly has both conscious and unconscious dynamics. Certainly anyone can assume any one of the three postures at any given time, but the ability to do it reflexively right is one of the keys to good health.
The ability to attain the proper posture in any given environment is the result of your muscle’s relationship with your brain, and vice versa. That steady relationship keeps your muscles balanced and your skeleton aligned. Only then can your muscles operate with peak efficiency while reducing the strain on your body caused by the natural gravitational forces.
Good posture works for you, not against you. Standing up straight is not just a command.
Joint receptors of the feet, and the muscles that support the foot contribute to the positive support phenomenon—that reflex that stands you up straight. The positive support phenomenon converts the lower extremities into firm but compliant pillars. Merely rising to your feet causes a reaction in your brain and spinal cord that makes your whole body defy gravity. Further, compression of a joint—as when weight bearing—instinctively evokes facilitation of extensor muscles while traction as in hand suspension facilitates flexors. Similarly, if the bones of the toes are squeezed together or flexed instead of being normally spread apart, as if they are jammed into a wrong sized shoe, all the joints of the lower limb tend to flex and gravity wins. (This is an excellent reason why shoes must fit right.)
Antigravity muscles are designed to contain copious mitochondria, which make ATP to build endurance for upright posture. However, when the antigravity structure breaks down, the population of these cellular powerhouses wanes and gravity takes over. Muscles that should produce upright posture become frail leading to joint breakdown and other structural problems. The feet, knees and hips all start to flex weakening the
Of all the characteristics of being human, good posture has to do with the ability to stand upright against gravity for long periods
lower back. When any one of these three joints of the lower extremity flexes the other two also flex (and when any one of these three joints extends, the other two also extend). That can affect neck and shoulder posture, too.
Once the afferents of joint mechanoreceptors—better known as proprioceptors—reach the cord, interneurons create a broad display that is especially effective in modifying activity in ipsilateral and contralateral muscles, reaching up and down the cord several levels. Their effects vary with the central integrative state of the neuronal pool. In other words, if a joint is in flexion it will elicit a different pattern of response than if that same joint is in extension, each condition relative to its homologous involvement.
Posture is Not What You Think
Posture is all about the arrangement of the body and its limbs, but it is not a conscious event. Whether good or bad, a person’s posture displays the functional nature of their nervous system. It has to do with the unique way each person carries his or her body as a whole, either intentionally or unintentionally.
A few of the traits that distinguish humans from other species are self-awareness and morality,speech and symbolic cognition, nimble thumbs, upright posture,conscience, sociability, and the capacity to imagine.
The natural, neutral, or healthy spine should be straight when viewed from the back is not straight when viewed from the side. (The spinal condition cannot be seen from the front, but certain aspects of its functional status can be seen, for example, in upper and lower limb carriage, hip height, etc.) The spine should have four natural spinal curves—two lordotic and two kyphotic curves—that sweep forward and backward, respectively. From the top
downward, the cervical spine curves forward, the thoracic spine curves backward, the lumbar spine curves forward again and the sacral spine curves backward again. Together, these four curves provide for resilience and the ability to resist gravity. This minimizes the stress to the vertebral joints, the core (paraspinal) muscles, and the surrounding tissues.
The fundamentals of upright posture require that a plumb line fall through the anatomical center of the body. From the side view, that line would intersect the back of the ear, through the center of the shoulder joint, through the center of the pelvis, and through the center of the ankles.
From the front view, the plumb line should fall through the center of the head, long the spine and right through the center of the sacrum, and land equally placed between the feet (see the diagrams, above).
Posture in Motion
Of all the characteristics of being human, good posture has to do with the effortless ability to be bipedal—stand upright against gravity for long periods. But good posture does not stop there. We also desire to move around in our environment and do things. The ability to put one foot in front of the other and get from place to place requires a constant and pre-programmed updating of all the input that would allow that activity. Greater muscle tone produces greater resistance to stretch and faster response to perturbation.
The functional spine maintains its normal alignment of each vertebra to the next while standing, sitting, and/or lying down, with or without movement. The fundamentals of normal human movement support and encourage the proper relationship of spinal mechanics.
In contrast, the dysfunctional spine leads to improper posturing, especially when walking, or standing for long periods. Poor posture puts increased stress on the back causing discomfort and structural damage with an increased tendency to injury. Moreover, according to certain laws of orthopedics and spinal performance, a dysfunctional spine modifies or molds itself—the results of poly-anionic glycosaminoglycans (PAGs) that create arthritis—as a consequence of a person’s lifestyle. For example, sitting for long periods in ergonomically wrong positions makes people more prone to spinal stress and muscle pain from misalignments and joint breakdown.
Postural flaws can also present with a forward tilt of the hips, an increase in the curve of the lumbar (lower back) spine, and a protruding stomach. This position places stress over both of the hip joints and lower back.
Anti-gravity Muscle Function
Anti-gravity muscles move the bones into their compliant and supporting posture. When these muscles do their job, one could stand forever. However, the truth is that these muscles fail. How can you tell when they fail? A misfiring muscle is accompanied by a burning sense in that muscle. The joints often ache and movement is often difficult, slowed, and painful. However, it may be that there are no indications of muscle problems unless the muscles are tested.
Muscle testing can reveal the functional nature of those structural supporters. For example, when standing upright in the
neutral posture, all anti-gravity muscles should be functionally facilitated. There are many muscle tests that can be used, but most commonly two basic muscle tests—using the clavicular portion of the pectoralis major (PMC) and the latissimus dorsi (LD)—can give a satisfactory picture.
The Static Posture
The ability to stand upright stems from many factors, one of which is the positive support phenomenon. It is based on the perception that putting pressure on the feet as with standing from a seated posture turns on the muscles that resist gravity. It causes the muscles of the lower extremities to work together to stabilize the body and to support its weight.
Watch people as they stand. Check a friend. See the level of the base of their skull as it sits on the neck. Is it level, high on one side, or low on the other?
Next check the level of their shoulders. Is one shoulder held higher than the other? Are the shoulder blades level? Does the inside edge of the shoulder blades flare in whole or in part?
Check for any tension on one side of the spine relative to the other. The area immediately lateral to the spine is all muscle. Any tension on one side compared to the other can mean that the spinal joints are not moving symmetrically through that area. That can set up hemisphericity that contributes to this structural dysfunction.
Look at the highest part of the hips on each side. Is one hip held higher than the other? Place your thumbs on the hipbone—the posterior superior iliac spine, or PSIS—on either side and ask the patient to slowly lift one knee toward their chest, then the other one. The right response is for the hipbone on the side being tested to rise a bit relative to the hipbone on the other side (i.e., Trendelenburg’s test). If the PSIS on the side of the raised leg drops instead of rises, this is an indication of hip joint instability. As a result, you should also check their ankles and feet.
The ankles and feet must bear weight properly; they are the whole body’s structural foundation. Any flat-footedness can contribute to postural problems and the further breakdown of the anti-gravity muscles that make up the lower extremities like firm but compliant pillars. Recall what was stated earlier that foot or toe compromise can lead to ankle, knee, and hip involvement.
The Abnormal Posture
Abnormal posturing is different from "bad posture" or "slouching.” An abnormal posture is a deliberate or reflexive tendency to hold a particular body position, or to move one or more parts of the body in a particular way.
Certain abnormal posturing behaviors may indicate specific lesions to the nervous system. It could be a sign of some local involvement or it might be a more serious sign of central nervous system damage. However, there are other common causes of abnormal posturing—soft signs—nonetheless central nervous system lesions.
Normally, when a muscle contracts, the muscles on the opposite side of that joint provide some resistance to contraction to maintain stability. That is a type of posturing, too. Abnormal posturing occurs when damage to the central nervous system (brain and/or spinal cord) results in complete or partial lack of opposition to muscle contraction in various muscle groups.
While abnormal posturing is often observed as an involuntary flexion or extension of the arms and/or legs indicating severe brain injury, it also displays in more functional situations. The hard signs of abnormal posturing occur when one set of muscles becomes hampered while the opposing set is enabled, and an external stimulus such as pain causes the working set of muscles to contract. The posturing may also occur without a stimulus. The hard signs of abnormal posturing are an important indicator of the amount of damage that has occurred to the brain, and are one key to the severity of comatose states in both adults and children.
Soft postural signs can display much the same way as do hard postural signs, but without the pathology of frank tissue damage. The soft postural signs are functional, responding to dynamic processing problems in the central nervous system, but they can often be corrected with certain manipulative therapies.
Upright posture is one of several uniquely human traits. The bipedal posture allows humans to move about and interact with their environment. It only makes sense that that movement should be symmetrical and reciprocal, and accompanied by balance. However, as a result of inappropriate sensory input, the functional posture can easily lose its stability, and that is when joint and muscle problems develop leading to various types of aches and pains, and an increased potential for injury. Structural compromise also involves organ function, especially the eyes and ears, and the ability to remain upright in one’s own environment.
Poor posture results when certain muscles tighten up—or shorten—while others lengthen and become weak, which often occurs as a result of one’s activities of daily living. In order for muscles to work properly they must be at their optimal length. It does not matter if a muscle is in spasm or stretched, if a muscle’s origin and insertion get too close together or too far apart, the muscle becomes functionally inhibited—it shuts off.
Muscles need calcium to contract and ATP—from mitochondria—to relax. If the population of mitochondria falls, then the ability of the cells to make ATP also falls and the muscles stay in a state of contraction.
Poor posture can show up in several different ways. It can present with rounded and elevated shoulders and a push-forward head position (see the illustration to the left). This posture places stress on the spine between the top of the neck and skull, and the base of the neck and upper shoulders. This also leads to shoulder girdle instability, resulting in compromised upper extremity movement patterns.