Most Likely. The most common compression neuropathy is carpal tunnel syndrome. Compression neuropathies can be mild and no problem or can be severe leading to permanent tingling, numbness, and weakness. What area is the compression neuropathy? And how symptomatic is she?
Yes. This may depend on the cause and the extent of the compression. Those kind is issues can be very serious if in the neck than in the back. You should be worried and so should your sister. She should see her doctor asap.