Unusual experience defies explanation

[TSandM]

John -- numbness throughout the entire hand evenly, or distributed over certain fingers? Although a low cervical disc is a possibility (aggravated by hauling gear AND by the extreme neck extension of perfect trim), another possibility is carpal tunnel syndrome -- and the history of having it happen to you when you are driving, and when you are asleep, is much more suggestive of carpal tunnel.

 

[Divedoggie]

I'm really unconvinced that a slipped disk which exerts enough pressure on nerves to cause numbness would "clear up" so quickly without further symptoms. I'm leaning much more toward Dr Lynne's hypothesis of CTS.

It seems likely related to hauling gear or maintaining a static position for long periods of time while underwater, or a combo there of. Mild DCI cannot be ruled out since it only happens after these Rock Lake expeditions, but it wouldn't "clear up" spontaneously either.

This has really got me thinking though. My hands really bother me too, as I drive back home from Santa Rosa. I continually flex and manipulate them because they feel a little numb and strange as I hold the steering wheel.

If its not DCI or a physical issue, then maybe its a chemical issue. A possibility is electrolyte imbalance and becoming slightly hypokalemic. Dehydration coupled with strenuous exercise and limited food intake, and tempurature changes could possibly mess with serum levels of potassium, which would cause muscle weakness, etc. Problem is that the heart is a muscle and could be affected as well.

 

[peterbj7]

I obviously bow to Lynne's medical knowledge and training. I have none. But speaking from my own experience only - I've had upper spinal problems for several decades, and diagnosis has shown that I was born with them - symptoms like tingling, loss of feeling, loss of strength CAN vanish very quickly once pressure on the affected part of the spine is relieved.

 

[boulderjohn]

John -- numbness throughout the entire hand evenly, or distributed over certain fingers? Although a low cervical disc is a possibility (aggravated by hauling gear AND by the extreme neck extension of perfect trim), another possibility is carpal tunnel syndrome -- and the history of having it happen to you when you are driving, and when you are asleep, is much more suggestive of carpal tunnel.

In this case, it was very pronounced in my thumb, index finger and the middle finger.

Carpal tunnel is interesting. I type a lot, and I do it very badly (as I am sure you noticed!), so it would not be out of the question.

In my original post, I mentioned scootering and said it could be a factor. I did one dive with a Silent Submersion scooter I had never used before. It has an interesting throttle mechanism that I found to be very challenging. It is like the throttle on a motorcycle, and I had a hard time finding a way of keeping it rolled back comfortably.

 

[boulderjohn]

I want to thank everyone for their thoughtful comments. I will be checking the suggested possibilities.

 

[TSandM]

John, thumb, index and middle finger would be HIGHLY suggestive of carpal tunnel. This is the distribution of the median nerve, which passes through the carpal tunnel at the thumb side of the wrist. A cervical disc would be more likely to produce symptoms which would be evenly distributed through the hand, as the low cervical nerve roots distribute in all three nerves that serve the hand.

 

[Duke Dive Medicine]

Hi John,
Agree with Lynne that it might be carpal tunnel. I'm not so sure that it's related to c-spine issues since you'd likely see it at other times besides diving. Another possibility is brachial plexus injury/inflammation from the weight of the tanks. Take a look at the picture in the link - the shoulder straps of your tanks run right over the top of the brachial plexus.
Brachial Plexus
That would be my first guess.
Cheers,
DDM

 

[boulderjohn]

John, thumb, index and middle finger would be HIGHLY suggestive of carpal tunnel. This is the distribution of the median nerve, which passes through the carpal tunnel at the thumb side of the wrist. A cervical disc would be more likely to produce symptoms which would be evenly distributed through the hand, as the low cervical nerve roots distribute in all three nerves that serve the hand.

Hi John,
Agree with Lynne that it might be carpal tunnel. I'm not so sure that it's related to c-spine issues since you'd likely see it at other times besides diving. Another possibility is brachial plexus injury/inflammation from the weight of the tanks. Take a look at the picture in the link - the shoulder straps of your tanks run right over the top of the brachial plexus.
Brachial Plexus
That would be my first guess.
Cheers,
DDM

Can you explain why it suddenly and instantly resolved itself in this case?

 

[TSandM]

The only supposition I could make about the sudden resolution is that you changed the position of the wrist and relieved the pressure. Typically, carpal tunnel symptoms are worse, or can be reproduced by holding the wrist in flexion (which is why symptoms occur at night, because many people sleep with their wrists flexed).

 

[Duke Dive Medicine]

Can you explain why it suddenly and instantly resolved itself in this case?

John,
This is speculation, but if carrying the heavy tanks resulted in inflammation of the area around the brachial plexus, you may have had some edema in there that impinged on the blood flow to one of the nerves that branch off the plexus, likely the radial nerve judging by your symptoms. Movement of the shoulder could result in worsening symptoms if inflamed connective tissue impinges on a nerve or circulation, as you noticed while driving, sleeping on the affected side, or reading the paper. When the insult (the heavy tanks) goes away, the inflammation starts to improve. When you shook your arm out the last time, you may have popped some connective tissue which was already in the process of healing and suddenly relieved some pressure, which allowed for better circulation to the nerve.

As I said, that's my own opinion. I've seen a couple of other cases where tight equipment resulted in brachial plexus inflammation and symptoms similar to what you're having, but there could be other valid explanations. One way to find out would be to carry the heavy tanks differently next time and see what happens. Also, while on your dive trips, be mindful of any shoulder movements you're performing that are unusual - something else may be aggravating it as well.

Cheers,
DDM