If a person long-term preference for the whole night or most of the time lying on the side, and fixed side, the side of the shoulder joint, the deltoid muscle and the armpit will be in a state of long-term pressure, resulting in these areas of the soft tissue and vascular nerve bundles of the blood supply serious obstacles to normal metabolism; gluteal plexus nerve due to ischemia and hypoxia and paralysis, caused by the upper arm or even the entire upper limb numbness; lateral position shoulder joint internal rotation, can cause the anterior capsule of the joint capsules for a long time to cause cardiovascular inflammation. The shoulder joint in side-lying position can cause the anterior joint capsule to be stuck for a long time, resulting in aseptic inflammation of the joint capsule; axillary nerve compression for too long can cause deltoid muscle paralysis and deltoid muscle regional sensory disappearance, and in the long run, it can result in deltoid muscle atrophy, and ultimately form a “square shoulder”. In addition, heavier or obese people lying on their side for a long time, will also cause wear and tear between the bony structures of the shoulder joint and extrusion, affecting the mobility and coordination of the joint. In short, side lying too long can lead to frozen shoulder. And patients with frozen shoulder, such as hobby side lying, due to blood circulation obstacles to aggravate the condition, get up in the morning will feel shoulder pain, shoulder activities more limited, can be said to “add to the problem”. Long-term fixed side lying is certainly not good, but a short period of time to rotate side lying is not exclusive, in fact, it is impossible to eliminate side lying. Most people sleep in a variety of sleeping positions automatically alternate, including the left side of the bed, lying on the back, the right side of the bed, there are a few people like to lie prone, reclining. When one sleeping position becomes uncomfortable, one will change to another, albeit subconsciously and automatically while sound asleep. Only people suffering from a certain disease, the doctor will specify a specific sleeping position, such as lower extremity traction of the fracture patients, can only lie on their backs, is not allowed and impossible to lie on their sides; left side of the rib fracture patients, only to take the right side of the lying position is more comfortable, lying on their backs is prone to cause pain. Therefore, even healthy people; sleeping position at night also have to pay attention to. A good combination of sleeping position, can be beautiful to do a good dream, the next day can be full of energy to work. A bad sleeping habits, such as long-term fixed side lying, will cause chronic damage to the shoulder joint and its surrounding tissues, affecting the health of the body. From the perspective of shoulder protection, a reasonable combination of sleeping principle is: the shoulder is always placed in a relaxed and comfortable, neither pulled nor squeezed in the dynamic balance.