Brief Answer:
Please Rule out Cervical Rib or Cervical Outlet Obstruction

Detailed Answer:
Hi,

Welcome to Healthcaremagic.

I am Dr.Bruno.

I am sorry to hear that your left arm is blue & numb, at times (few) totally numb for a few minutes while the right arm is pink and fairly normal for a couple of months and you are also having a vertigo problem

I have read your question with care and understand that You have also undergone a MRI and X Ray of Neck and Ultrasound of the neck veins

Let me try to help you

Bluish Discolouration coupled with Numbness in one arm while the other is pink and fairly normal suggest that there is problem in the Blood Supply to your Left Arm.

The Blood Vessels supplying to your left Arm is narrowed in one or few places and hence the blood flow is affected. Since the Blood Flow is affected, it takes lots of time for the bad blood (blood with less oxygen and more waste) to get out of your arm and good blood (blood with more oxygen) to come into your arm. Because of this, your arm is bluish.

Because of reduced blood flow, nerves in your arm are getting less oxygen and their function is impaired. Hence they are not transmitting signals. This leads to numbness

The way forward is to identify what causes the obstruction and the site(s) of the obstruction. For this we may have to do few more tests

1. There is a Test called Doppler. This will give you fairly good idea as to where is the obstruction.
2. Then we may have to do a test called Nerve Conduction Study to know how much nerves are affected
3. You may also need a CT Scan of your Neck including your upper chest

In most cases, you will be diagnosed with what is called as Thoracic Outlet Syndrome or some causes of Arterial Narrowing

The management will differ as per the exact cause of obstruction and exact level of obstruction

We have seen that Bluish Discolouration and Numbness occurs because of reduced Blood Flow to your Arm. Same Way when the blood flow to your brain is reduced, you will be having vertigo. It is highly likely that both are related and the actual problem is in your neck which is causing one problem in your arm and another problem in your brain.

Hope you found the answer helpful.

If you need any clarification / have doubts / have additional questions / have follow up questions, then please do not hesitate in asking again. I will be happy to answer your questions.

Let me know if I can assist you further.

Take care.

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