The quadratus lumborum muscle, known as the QL, is an important lower back muscle that connects your spine to your pelvis. Pain in the QL can be due to overuse, stress, and strain because muscles cause pain and stiffness when they're weak or too tight. Activities such as sitting for long periods of time can reduce blood flow to an area, especially in the QL and surrounding areas.
Apart from being painful, QL pain can also increase the load on quite a few other structures. Often, when one side tightens up, it can minorly lift that side of your pelvis. Even though your back cannot "go out of place," this tightening and lift can make you feel misaligned or "out of place." It can also pull at your ribs, tilting you to the side, limiting your reaching, and restricting your breathing. Finally, if the QL is tight on both sides, your spine can become compressed. You may experience a sharp pain in your lower back, pain when turning in bed or standing from sitting, and even scoliosis due to asymmetrical tension.
In order to avoid pain in the QL, try out these stretches using the Backbridge: