Thanks for the query to H.C.M. Forum.
I would come up with these possibilities for this numbness
in the right arm , these includes.
1 Occlusion of blood supply , this is the main cause of numbness at this age od 52 years , atherosclerosis
may be the most prominent cause.Diagnosis can be confirmed by color doppler test.
2 Neuropathy as you mentioned that beside numbness there is pain also . Diagnosis can be confirmed by physical examination and clinical history . M R I is also an important test.
3 Cervical spondilitis may be the one more reason. Diagnosis can be confirmed by X Ray
& m r i of the neck.
In my opinion consult a neurologist
and get his opinion as above mentioned.
Good luck. Dr. HET