Problems arise when your capacity for healthy movement is reduced or limited by pain. These medical doctors specialize in providing non-surgical and surgical treatment options to reduce your pain and keep you from further harm.
Consider the most common twisting you do in a day:. The small groups of muscles situated closest to your spinal column, called spinalis muscles, are the muscles that allow you to twist, bend and move your body in various positions and in different directions.
Injuries occur when you subject these muscles to unusual or unnecessary stress, such as overstretching or doing excessive amounts of heavy weightlifting. The upper section of your spinal column is known as the thoracic spine. But there are certain situations that can cause harm to this part of your back, such as:. The lower section of your spinal column is known as the lumbar region. To keep things simple, we're going to focus on structures with a circular cross section, often called rods or shafts.
When a torque is applied to the structure, it will twist along the long axis of the rod, and its cross section remains circular. To visualize what I'm talking about, imagine that the cross section of the rod is a clock with just an hour hand. When no torque is applied, the hour hand sits at 12 o'clock. As a torque is applied to the rod, it will twist, and the hour hand will rotate clockwise to a new position say, 2 o'clock.
The angle between 2 o'clock and 12 o'clock is referred to as the angle of twist , and is commonly denoted by the Greek symbol phi. This angle lets us determine the shear strain at any point along the cross section. Before we get into the details of this equation, it's important to note that because we're only discussing circular cross sections , we've switched from Cartesian coordinates to cylindrical coordinates.
We can immediately learn a few things from this equation. The first thing might be obvious: the more angle of twist, the larger the shear strain denoted by the Greek symbol gamma , as before. Second, and this is the big difference between axial-loaded structures and torque-loaded ones, the shear strain is not uniform along the cross section.
It is zero at the center of the twisted rod, and is at a maximum value at the edge of the rod. Finally, the longer the rod, the smaller the shear strain. So far, we've focused our attention on displacements and strain. To discuss the stress within a twisted rod we need to know how torque and stress relate. Since twist applies a shear strain, we expect that torque will apply a shear stress. The relationship between torque and shear stress is detailed in section 5.
If you have insomnia, you may find yourself moving around a lot in bed, unable to get to sleep. Some chronic pain conditions, such as arthritis and fibromyalgia , can also make it difficult to get comfortable in bed at night.
Other causes of poor sleep and frequent tossing and turning, such as sleep apnea and insomnia, can be managed with the help of a medical professional. They may also perform a series of tests, such as a sleep study , to determine if there are underlying medical conditions.
If your doctor has diagnosed you with a condition that could be causing poor sleep, finding a treatment plan is the next step. There are many reasons for tossing and turning at night, including poor sleep hygiene, an unbalanced diet, and even underlying medical conditions. Practicing good sleep hygiene, such as turning off electronics and keeping a consistent sleep schedule, can help you stop tossing and turning so much at night.
This article lists 17 evidence-based tips to sleep better at night. Getting good sleep is very important for optimal health. By blocking blue light in the evening, you can prevent the disruption in the natural sleep-wake cycle caused by artificial lighting and electronics. Stretching before bed can help you not only fall asleep faster, but also stay asleep.
Learn how to do eight stretches that may help to improve the…. Herbal teas are popular beverage choices when it comes time to relax and unwind. Here are the 6 best teas that help you sleep. Experts say you can prepare for the end of daylight saving time for days in advance. Among the recommendations is outdoor physical activity. Here's everything you need to know about shopping for the…. Sleep trackers are equipped with tools and features, such as sleep duration and quality, heart rate, blood oxygen level, that can help you make….
0コメント