Hi, I had gone through your question and understand your concerns. It is difficult to say if the numb area will spread or no. You need a nerve conduction testing (ENMG) in order to evaluate the degree of nerve damage
and the exact place of damaged area. This and clinical observation ( if you are experiencing worsening of numbness
in time) can show if the numbness will progress or not. Hope this answers your question. If you have additional questions or follow up questions then please do not hesitate in writing to us. I will be happy to answer your questions.