Occasionally I wake up to find my arm has lost all feeling. I can’t move it by itself, I can’t control anything for a short period of time. I have to pick my arm up and move it, and wait for it to slowly tingle back until I can use it again. Today the same thing happened, but it’s scaring the shit out of me.
I’m assuming it’s a more severe form of a bodypart ‘falling asleep’ in that the blood supply is probably cut off from me sleeping on it. From now on I’m going to sleep on my back, but what exactly causes this to happen? Would it be possible for you to lose an arm that way? Anyone else had a similar experience?
This is called a neuropraxia. In more severe cases it lasts for long periods (i.e. Saturday Night Palsy). Via compression, you are interrupting nerve signals to the distal nerve causing decreased sensation and motor output (depending upon the duration of compression & damage to myelin sheaths/schwann cells). It can also feel cold due to the altered sensation, as well as altered blood flow, as nerves usually travel in the limbs in neurovascular bundles. This can be seen often following surgery upon extremities due to tourniquet induced denervation. This is why its a bitch to get muscles working again after, say, an ACL surgery (quadriceps specifically). I really wouldn’t be worried about it unless it takes 30 minutes or more for you to regain full sensation and motor output. My advice: sleep in a different position!
I’ve also read somewhere on the site that if you are getting big (lbm wise) and you’re not balanced, that you could be pinching a nerve and thus your arms fall asleep, although I’m not sure on how true that is and if it applies here.