Sleeping without feeling the arm, like a broken, may be due to the following reasons: 1, may be due to long-term pressure on the upper limbs, often seen in the patient in the sleep unconsciously will be resting on the back of the head, or due to excessive side-lying led to a side of the limb long-term pressure, will lead to the upper limb of the large blood vessels are compressed, which leads to the upper limb of the poor circulation of the sensory loss of the patient wants to alleviate this situation, often Need to use the other side of the hand to drag this side of the upper limb, after a long time to be able to gradually regain consciousness. 2, may be due to vascular lesions of the upper limb, such as in the upper limb arteries within the embolism, or even due to other reasons lead to occlusion, will also appear in the process of sleep. 3, may be due to serious cervical spondylosis, for example, in the patient suffers from a serious radiculopathy cervical spondylosis, may be triggered in this kind of disease aggravation, in the case of a serious cervical spondylosis. induce the aggravation of this kind of disease, the neck may be in an improper position during sleep, which in turn leads to the aggravation of this kind of nerve compression, and may also produce the above symptoms.