leg weakness

my father in law had lower back surgery quite a few years ago and all went great without any additional problems. he just recently had arm and hand problems and was told to get the cervical disk surgery and he is willing to do that but will that be effecting the muscles in his legs. they are so weak. do you think the surgery will help this or is this something else.

[Achey916]

Usually not, but it could especially if his cervical disc issue is protruding backward toward the spinal cord.  Also cervical stenosis, if severe, can cause all kind of rpoblems way below the cervial level. Did he do an MRI to cervical spine?