What’s Up Doc? Friend’s arm is paralyzed after a night of heavy drinking

Q:  My friend is only 29, but when he passed out drunk the other night he woke up with his left arm paralyzed. How did passing out drunk cause a stroke?

A: The brain, the master control center which along with the spinal cord makes up the central nervous system, controls the body by sending electrical signals from the neurons in the brain to the nerves (think of these as the wires that conduct the control signals to/from the muscles, sensory receptors, etc.).  Some of these nerves go directly from the brain to the things they control, called cranial nerves; for example the nerves that control smell, vision, eye movement, sensation and movement of the face, hearing, tongue movement, head movement and some other body functions. For the rest of the sensation and movement of the body the brain utilizes nerves that travel via the spinal cord to the things they control, for example sense and movement of the arms and legs, etc.  Once these nerves leave the spinal cord they are called peripheral nerves.

Your friend’s condition sounds like it might be a “Saturday Night Palsy” (SNP), an issue with the peripheral nerve(s) that controls the arm, affecting it at the level of the armpit/arm and not in the brain (strokes affect the neurons in the brain directly, not just the peripheral nerves).  SNP is most often due to compromise of the radial nerve from prolonged direct extrinsic pressure on the axilla (armpit) or the upper arm, although other intrinsic causes of compression of the nerve (for example from a mass, a broken bone, others) are also possible. 

What’s Up Doc? Treatment is available for pernicious anemia

SNP got its name because some cases were noted to occur when someone got drunk and passed out with their arm draped over the back of a chair, compressing the radial nerve where it passes through the axilla.  However, it can occur from other situations, such as having someone fall asleep with their head and/or shoulder on the patient’s upper arm, again compressing the radial nerve, but in this case the compression occurs where the nerve travels through the upper arm (this is sometimes called “honeymoon palsy”), or in many other ways. 

Why are my friend’s scars worse than mine?

SNP occurs in roughly 3 per 100,000 men and about half that number of women. The diagnosis is typically made by a detailed history and physical exam, although sometimes certain tests, such as an X-ray (specifically to look for a fracture or mass), CT and/or MRI imaging scan may be done to rule out other conditions and/or to look for certain causes of the nerve compression, and possibly even nerve conduction studies and/or needle electromyography may be indicated.

What’s Up Doc? Treatment is available for pernicious anemia

SNP is typically treated with a wrist splint to support the hand and physical therapy.  Other treatments may involve localized injections to decrease inflammation, and in selected cases surgery, which may be indicated if the compression is due to an intrinsic process which can be surgically corrected, as well as in some selected cases where a nerve graft or other intervention may be possible.

The prognosis of SNP depends on the specific cause of the nerve compression.  If the compression is a typical SNP or honeymoon palsy as noted above, the timing and extent of recovery depends on the extent of the nerve damage, but even in mild cases the symptoms typically take months to resolve.

Jeff Hersh, Ph.D., M.D., can be reached at DrHersh@juno.com