Numbness may indicate thoracic outlet syndrome.
This article was published in Rock and Ice 205 (October 2012).
About 10 days ago I noticed numbness in my left-hand pinky, and a bit in my ring finger. I thought I had pinched a nerve climbing, then last week I spent two days typing, tried to climb after the second day and my grip was just weak. Should this fully resolve itself? Could muscle wasting have occurred already?
—KO, Carbondale, Colorado
First go climbing, since avoiding it won’t actually help a lot, and find something to laugh about.
It sounds like a case of thoracic outlet syndrome. The ulna nerve, which supplies sensation to the little finger and half of the ring finger is usually the first to be compromised, as it is the lowest on the brachial plexus and has to pass up and over the first rib and under the collar bone. When the muscles around the neck and shoulders tighten from overload, the first rib becomes slightly elevated, tensioning the nerve. To make matters worse the space under the collarbone is reduced and tight muscles further compress the nerves after they exit the cervical spine.
Stretch like a yogi, especially your neck and shoulder girdle (Check out the video on my web page, http://www.drjuliansaunders.com)
See a PT, osteo, chiro or whatever floats your therapeutic boat. When you feel the numbness coming on, take a few minutes to stretch your neck in all directions.
The pattern of finger numbness you mention, without significant pain in your lower neck, makes a disc bulge not likely. That said, the referred ache down your arm does make me a little suspicious.
If the whole issue does not respond to some manual therapy, move up the medical ladder and get some imaging as recommended by your physician.
Muscle wasting will be infinitesimally small and entirely transient in the short- to medium-term.