Numbness under arm after BA. Is this normal or have I ended up with nerve damage?

Hi,Numbness can occur post surgery for two reasons, nerves have been a pulled on, such as when the foot goes to sleep when you sit awkwardly. Or if the nerve has been injured or divided.Like the foot that is numb, time allows the normal feeling to return, whereas if the nerve is damaged it will not recover and the numbness can be permanentI suggest review and discussion with the surgeonAll the best 

When any incision is made in the body, thousands of nerves are transected (cut).  The majority of the time the nerves will regenerate and the feeling will return.  However, nerves grow very slowly and it may take 9-12 months for the feeling to return.  It is also possible that the numbness is permanent, this is one of the risks of implant surgery.