How can poor posture result in back pain

Poor posture can lead to back pain by causing problems with your intervertebral discs and joints, as well as your muscles.

Poor posture can place stress on your spine that can lead to anatomical changes in the spine such as shifting of discs and adjustments to the natural curvature of the spine. These changes can ultimately cause back pain due to the constriction of blood vessels and nerves, causing pain. For example, standing or sitting in a position with your neck tilted too far forward for prolonged periods of time (common when using a cell phone) can add extra weight on the vertebra and strain the trapezius muscles, which can result in a change to the natural curvature of the spine. In other cases, such as sitting for long periods of time with poor posture, extra weight from the upper body can be placed on intervertebral discs of the lower back while they are unsupported. This uneven distribution of weight can result in pain caused by disc bulging in the spine and pinched nerves.

Additionally, with prolonged poor posture, muscles can become tightened and overstretched, leading to muscle fatigue and stiffness, causing pain. For example, standing for long periods of time with your weight more on one foot than the other can place extra pressure on one hip, which can overburden the muscles in the lateral hip region, causing them to tighten, while the muscles in the buttocks weaken. Over time, this will result in the development of muscle imbalances in the pelvic area, resulting in muscle strain in the lower back and causing pain. Similarly, a common poor posture position in which a person is "stooped", or stands with their pelvis tucked in and their back flat instead of naturally curved, creates muscle imbalances and a misalignment of the spine resulting in muscle fatigue and pain in the neck and back.

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