Left Arm Numbness

If you have left arm numbness alone it could be indicative of either a self limiting and benign disorder or potentially something more serious that needs to be looked into further. If you do have numbness in the left arm or tingling that is short live and lasts for minutes or seconds it could be just a pinched nerve, but may also be a transient ischemic attack. What is also important is that you distinguish between numbness, tingling and frank pain. Pain would potentially be more serious as pain in the left arm can easily be from a heart attack. This would be especially true if the pain radiates to the neck, back or shoulder. If the left arm numbness is of a more persistent nature you may in fact have had a stroke. It is recommended that you either call your Doctor or visit an urgent care center or emergency room should you have numbness that is persisting more than a minute or two especially if there is no trauma or you just didn’t wake up with a numb arm.

There are other causes of a numb arm and one of those includes thoracic outlet syndrome which we discuss here in another article. Briefly, it is essentially a compression of the brachial plexus as it exits the area of the spine. This acts to compress nerves. Symptoms are much more prominent with the arm all the way up to the sky and in fact you may have a congenital cervical rib that could be causing that particular compression. The only way to tell is with Xray films vs CT of the neck.

Nerve compression can also happen at the level of the cervical spine nerve roots and can cause pain along with numbness. These symptoms would evolve over what is called a dermatome which is a small area of skin innervated by the nerves. Take a look at the picture below and you will see exactly which nerve root is impinged based on the dermatome involved. An MRI of the cervical spine would be the best test to determine if this is a cause or not.


Anxiety or panic attacks can mimic left arm numbness or pain and is certainly another diagnosis to consider. Usually there are other symptoms associated such has palpitations, shortness of breath, feelings of anxiousness that will help you distinguish between anxiety and another more serious disorder that needs to be addressed.

Regardless left arm numbness and tingling could be a symptom of a dangerous disorder so regardless of what you read here you should contact your health professional