Arm pain and weakness of the hand can not make strength, may be cervical spondylosis, local muscle tears and so on. 1. Cervical spondylosis: cervical spine degenerative disease occurs when cervical spondylosis, may lead to cervical intervertebral disc dehydration and degeneration, resulting in the back of the spinal cord or spinal nerve root pressure, nerve compression will lead to the innervation area of the pain, arm soreness; if the disease progresses to lead to the anterior horn of the spinal cord motor neuron injury, there may be a decrease in the limb muscle strength symptoms, manifested in the hand to make the strength. 2. Localized muscle tearing: when the local muscles are severely torn or broken due to excessive stretching, the above symptoms may also occur. The tearing of muscles will cause the rapid accumulation of local metabolites, stimulating the peripheral nerve roots to appear soreness; at the same time, the muscle fibers can not complete the normal contraction after the break, will also be manifested as the hand can not make strength. Arm pain and weakness in the hand, there may be other reasons, it is recommended to go to the hospital in time, complete the examination to clarify the cause of the disease, under the guidance of the doctor to give targeted treatment or treatment.