A neutral spine
or good posture
refers to the "three natural curves [that] are present in a healthy spine
In human anatomy, the vertebral column is a column usually consisting of 24 articulating vertebrae, and 9 fused vertebrae in the sacrum and the coccyx. It is situated in the dorsal aspect of the torso, separated by intervertebral discs...
The word "posture" comes from the Latin
Latin is an Italic language originally spoken in Latium and Ancient Rome. It, along with most European languages, is a descendant of the ancient Proto-Indo-European language. Although it is considered a dead language, a number of scholars and members of the Christian clergy speak it fluently, and...
verb "ponere" which is defined as "to put or place." The general concept of human posture refers to "the carriage of the body as a whole, the attitude of the body, or the position of the limbs (the arms and legs)."
Webster's New World Medical Dictionary defines "neutral posture" as the stance which is attained "when the joints are not bent and the spine is aligned and not twisted." In this position, a person is able to completely and optimally attain balance and proportion of his or her body mass and framework, based on his or her physical limitations. Good posture optimizes breathing and affects the circulation of bodily fluids.
In medicine and occupations concerned with physical fitness, the concept of good posture is referred to as "neutral spine." In this context, proper posture or "neutral spine," is the proper alignment of the body between postural extremes. In its natural alignment, the spine is not straight. It has curves in the thoracic (upper) and lumbar (lower) regions. There is a slight forward curve in the lumbar region (lordosis
Lordosis is a medical term used to describe an inward curvature of a portion of the lumbar and cervical vertebral column. Two segments of the vertebral column, namely cervical and lumbar, are normally lordotic, that is, they are set in a curve that has its convexity anteriorly and concavity...
), a slight backward curve in the thoracic region (kyphosis
Kyphosis , also called roundback or Kelso's hunchback, is a condition of over-curvature of the thoracic vertebrae...
) and a slight extension in the tiny cervical vertebra at the top of the spine. In addition, the ears, shoulders, hips, knees and ankles are aligned as if a plumb line were running from the ears down through the torso into the legs and the feet. In neutral posture, the body is able to function in its strongest, most balanced position. Stress to the joints, muscles, vertebrae and tissue is minimized.
In contrast, a non-neutral spine leads to "improper posture, [that] especially when walking, puts increased stress on your back and causes discomfort and damage." When the spine is left in non-neutral posture for extended periods of time, it raises the diaphragm, preventing the body from taking a full breath. This can lead to reduced oxygenation throughout the body. It can also compromise the internal organs' performance by putting pressure throughout the abdomen. People who sit for long hours on the job are susceptible to a number of misalignments."
"Neutral spine" is ideally maintained while sitting
Sitting is a rest position supported by the buttocks or thighs where the torso is more or less upright.- Sitting on the floor :The most common way of sitting on the floor involves bending the knees...
Standing is a human position in which the body is held upright and supported only by the feet, referred to as an orthostatic state.Although quiet standing appears to be static, modern instrumentation shows it to be a process of rocking from the ankle in the sagittal plane...
, and sleeping.