Your question involves the numbness, tingling, and tightness that you are experiencing in your left arm.

This can be caused by a number of things:

1. Diabetes: Diabetes can cause peripheral nerve issues, particularly as you mentioned that you have "unsatisfactory control" over it. It is more common to the legs, however, it can realistically affect any area. This may be something you need to speak with your doctor about.

2. B-12 deficiency: B-12 deficiency may cause peripheral tingling as well. You mentioned that you have been taking B-12 for the past week, however, B-12 can be very difficult to replace in an oral form, due to common absorption issues. It is generally well known by most doctors that B-12 injections are the fastest way to replace the vitamin.

3. Bulging Cervical Disc: You did not mention if you have pain in the left side of your neck. However, a disc bulge in the cervical spine may compress on a nerve, and cause the sensations you are feeling down your arm.

4. Nerve Entrapment: Nerves, as they pass out of the spine travel under your collar bone and down your arm. A common site where nerves are being compressed by muscles and/or bones is under the collar bone, a common condition called "Thoracic Outlet Syndrome". This may also be a cause for the symptoms you are experiencing.

As you can see there are a few possible reasons for your symptoms. The first 2 may be ruled out by your physician, while the 2nd two you may need a referral to an orthopedic doctor or physical therapist for evaluation.

You also asked if anxiety could be related. Anxiety can increase muscle tone and increase excitability of your nervous system, which can exacerbate any current condition you may have. It may not be the root cause of your symptoms, however, may make them more noticeable.

Sam Visnic
www.Endyourbackpainnow.com/blog