Could it be DCS? A long and winding road

[bluebanded goby]

I'd be interested in whether any doctors or other medically knowledgeable folks here might have any comment on my situation.

When I took up scuba diving a couple of years ago, about 15 hours after one dive numbness and tingling emerged in my left hand, and pain developed in my left arm. These came and went and moved around. DAN recommended a consultation which led to a chamber ride. The symptoms seemed to resolve, and didn't recur on the plane home, but they came back later. Over the nearly two years since then various tinglings/numbness/pain have occurred and gone away in various parts of my left hand and arm. The consensus of the doctors I've seen seems to be that this was probaby never DCS, but could be related to an old neck injury from a whiplash event a few years ago.

After a little while scuba diving, I began to gravitate toward freediving, and did that pretty much exclusively for a year and a half. Then, this fall, I thought I might ease back into scuba, and signed up for a nitrox course. At the time I started the course I had had a pretty constant sensation in the lower two fingers of my left hand for several weeks -- sort of a rope-burn-like feeling as though I'd dragged my hand across a rug, except that the feeling was present all the time, day and night. About an hour after the first pool session for the nitrox class, pains developed in my left arm and, over the next few days, spread up until my shoulder, neck and left side of the face. Eventually all these feelings went away, and I'm back to the rope-burn-like feeling in two fingers of my left hand.

I thought it was farfetched in the extreme that this could be DCS-related, since I had only spent a few minutes in the pool at a depth of up to 8 ft. But since the sensations seemed to vary from event to event, I thought I'd go back and see a hyperbaric doctor to pursue the question of how to distinguish them from DCS. (I.e. after a few minutes in the pool the pains didn't concern me, but if I'd just done a dive to 90 fsw I might be somewhat more worried.)

The hyperbaric doctor agreed that none of this seemed to be DCS-related, but thought it wise to have some tests done to rule out various things. In addition to my hand/arm situation, he had noticed when he had examined me the previous year that I have a certain amount of insensitivity to vibration in my left foot, and thought I should see a neurologist. The neurologist at my HMO (Kaiser Permanente) checked me out briefly and said, essentially, "Yes, you have a slight insensitivity to vibration in your feet, but the main thing we'd worry about is diabetes, and you don't have it or any risk factors for it. So we suggest just tracking it."

When I saw the hyperbaric doc recently, he gave me a laundry list of tests to request from my HMO family doctor -- MRI of brain/neck; echocardiogram with bubble study; and RPR, Hep B, HIV, folate, B12, heavy metal screen and thyroid studies. My family doctor thought this was all overkill, but agreed to the blood tests and, reluctantly, the PFO test. He said he felt an MRI would be excessive, but instead approved a neck X-ray. All of this came back negative -- no signs of a PFO, nothing remarkable in the blood tests, nothing in the X-ray. My family doctor thinks that the sensations are just the result of stress, and that I should go ahead and dive and not worry about it. (He's a one-a-year diver himself.) When I mentioned that icing my neck has caused the hand sensation to decrease at times, he attributed this to a placebo effect. (I should also mention that a few other tests were run, such as an EKG to rule out the possibility that the pains in the left arm might be, say, heart-related.)

I passed all of the results by the hyperbaric doctor. His position is that I still need a brain/neck MRI. "You're reasonably young (48), otherwise in excellent health, and you deserve to know what's causing this," he said. He's reluctant to give me an all-clear to dive without such an MRI because he said he can't rule out the possibility that whatever is causing the hand/arm sensations might increase my susceptibility to DCS. (Of course I also recognize that he's being very conservative; he also said at one point, for example, "You know, you can also get bent in freediving." Not with the very shallow, short profiles I practice, I'd think.)

At the end of the conversation, however, the hyperbaric doctor thought it would be acceptable for me to try some very conservative scuba diving and see how it goes. He suggested keeping dives shallow and short (~33 ft for 30 minutes), diving on nitrox, and only doing one dive per day, at least at the outset. But he also wanted me to continue pursuing an MRI. If I pay out of pocket outside of my HMO system, he estimated it would be $800-$900, which is a nontrivial expense for me. Also, while such a test may or may not give us some idea of what is causing the hand/arm sensations, it may never give me any way to conclusively distinguish them from DCS. Other divers have sometimes said, "Just develop a good sense of what kind of symptoms you normally have so that you can tell when something is out of the ordinary." But the bedeviling thing about these is that they have moved around and manifested in different ways.

So, a somewhat long and messy story, but I'm curious about how other divers, and particularly doctors, react to this. What would you do if you were in my shoes? Pester my HMO for the MRI, or consider shelling out for one myself? Or stop worrying about it and just have fun diving, hand sensations or no? Or go back to freediving, or take up a nice safe hobby like skydiving? I don't mean to be a nervous nelly who obsesses over every minor body sensation, but these symptoms are sometimes a lot more than subtle. Thanks in advance for any input.

 

[BillP]

Howdy bluebanded goby:

I can't really give specific advice over the Internet, but from your description it sounds like you have a very thoughtful and thorough hyperbaric physician. Yes, some tests might have a low chance of revealing the problem, but all of them seem appropriate based on the history you describe.

Should you have the MRI? If I knew the results of the test I could tell you! Remember, in most states HMO's don't tell you what care you can or cannot have- they just tell you what care they will or will not pay for. Usually (well over half the time) when patients appeal medical decisions denying diagnostic testing or treatment, the HMO will come through and pay. If you pay for a test out-of-pocket and it does indeed yield a diagnosis, then it should be pretty easy to get an HMO to pay retroactively. But if the test is negative, you're likely stuck.

If I thought that I needed a non-urgent test and was turned down by the HMO, I'd appeal. If the appeal fails, I'd try a next level appeal- etc. If I exhausted the appeals process and still felt I need the test, I'd have it done, pay for it, and take my chances. How lucky do you feel?

You say that your hyperbaric physician does not feel that your symptoms are diving related, but I'm hearing that he feels they could interfere with diving (DCS diagnosis confusion, etc.) Do you dive anyway despite the symptoms and no diagnosis? Judgement call there, buddy. I can't recommend that someone dive if they have a contraindication to diving.

Good luck and keep us posted,

Bill

The above information is intended for discussion purposes only and is not meant as specific medical advice for any individual.

 

[bluebanded goby]

Bill, thanks for the comment.

Interesting idea that if I pay for the test out of pocket and it yields a result, the HMO is likely to pay. I'll have to think about that. Before I consider pursuing my HMO's formal appeal process, I thought I might try other avenues with that organization, such as going back to the neurologist who saw me last year to see if he might support the suggested MRI.

Re your comment: "You say that your hyperbaric physician does not feel that your symptoms are diving related, but I'm hearing that he feels they could interfere with diving (DCS diagnosis confusion, etc.) Do you dive anyway despite the symptoms and no diagnosis? Judgement call there, buddy. I can't recommend that someone dive if they have a contraindication to diving."

His specific point seems to be that he assumes there's some physical cause (such as a nerve lesion in the neck) that wasn't disclosed on the neck X-ray that's responsible for the hand/arm sensations, and he can't rule out the possibility that whatever this is could leave me more susceptible to DCS. This is why he is so interested in an MRI.

On the other hand it was my own concern that, regardless of what an MRI might show, assuming that the condition isn't fixable and I have to live with these sensations, there may be times when it is difficult to distinguish them from DCS. So I'm aware that there's a certain amount of a gamble in scuba diving as long as I experience these sensations. Except for one scuba pool session in the nitrox class, so far I've limited myself to relatively shallow and brief freediving for the past year and a half.

I'm interested in your statement that you can't recommend that someone dive if they have a contraindication to diving. From your point of view, are neuropathies such as these hand/arm sensations a contraindication to diving?

 

[Lloyd]

Have you ever hurt your shoulder our elbow on that side?
Is it your pinky and ring finger that hurt?
Lloyd

 

[BillP]

bluebanded goby said...

I'm interested in your statement that you can't recommend that someone dive if they have a contraindication to diving. From your point of view, are neuropathies such as these hand/arm sensations a contraindication to diving?

Any conditions that might cause symptoms that can be confused with DCS (like some neuropathies for example) are a relative contraindication to diving. I can't tell someone that it's fine to go ahead and dive with a condition that might cause them to be misdiagnosed, mistreated, or otherwise harmed- i.e. I can't recommend that they dive if they have one of those relative contraindications. Many people continue to dive with relative contraindications, but IMHO they should do so only if they fully understand the risks.

Sounds to me like you have a good handle on what the risks could be, so once you have all the information you need you can make an informed decision as to whether or not you continue diving.

HTH,

Bill

 

[bluebanded goby]

Re Lloyd's question, yes, it's the pinky and ring finger of my left hand that hurt and/or tingle most of the time. I can't recall ever hurting my shoulder or elbow, but I can't rule it out; the main memorable injury was the neck whiplash from an auto accident that I mentioned. Interestingly, one doctor found she could affect (stimulate or increase) the sensations in those fingers by pressing on the rear of my elbow and also, as I recall, pressing down on my head (pressing it downward against my neck). And, as mentioned, applying icepacks to the back of my neck appeared to me to alleviate the pain/sensation, at least on one or two occasions.

Re BillP's comment about relative contraindications, that's helpful to know. My goal would be to better characterize the range of ways that these sensations manifest before I resume anything but the most extremely conservative compressed-air diving, in order to avoid any confusion with DCS.

Thanks again for the comments.

 

[The Iceni]

bluebanded goby once bubbled...
Re Lloyd's question, yes, it's the pinky and ring finger of my left hand that hurt and/or tingle most of the time. I can't recall ever hurting my shoulder or elbow, but I can't rule it out; the main memorable injury was the neck whiplash from an auto accident that I mentioned. Interestingly, one doctor found she could affect (stimulate or increase) the sensations in those fingers by pressing on the rear of my elbow and also, as I recall, pressing down on my head (pressing it downward against my neck). And, as mentioned, applying icepacks to the back of my neck appeared to me to alleviate the pain/sensation, at least on one or two occasions.

I think we've visited this problem before BBG.

Ulnar nerve or cervical nerve root compression are high on my list of differential diagnoses, particularly if there is a history of cervical spine injury..

 

[bluebanded goby]

Paul, thanks for the comment. We did indeed trade some messages about my situation a few weeks ago, although I don't recall you mentioning ulnar nerve or cervical root nerve compression specifically. The main news now is that all of my tests have been completed, prompting the latest discussion with the doctors about the merits of an MRI.

If I'm feeding your comment correctly through my Google-powered layperson's medical terminology decoder, I gather your thought is that this could be compression of the nerve that runs to those fingers, the compression either occurring at the elbow or where it joins the spine at the neck?

Two questions come to mind:

-- Would the fact that in a recent episode the pain started in the forearm and then moved to the upper arm, then shoulder, then neck, then a bit into the face argue in favor of the problem being in the neck rather than in the elbow?

-- If the problem is in the neck, would you normally expect it to be visible in an X-ray? Would there be cases in which an MRI might disclose a problem site of this type that isn't visible on an X-ray?

Thanks again for the comment.

 

[The Iceni]

bluebanded goby once bubbled...
. . . I gather your thought is that this could be compression of the nerve that runs to those fingers, the compression either occurring at the elbow or where it joins the spine at the neck?

-- Would the fact that in a recent episode the pain started in the forearm and then moved to the upper arm, then shoulder, then neck, then a bit into the face argue in favor of the problem being in the neck rather than in the elbow?

-- If the problem is in the neck, would you normally expect it to be visible in an X-ray? Would there be cases in which an MRI might disclose a problem site of this type that isn't visible on an X-ray?

OK BBG,

Nerves are like telephone lines. If you were unfortunate enough to suffer an amputation the irritation of the nerve stump, where it has been severed, often leads to "phantom" pain and sensations in a foot that is no longer there. The brain receives messages from the nerve that formally lead to the foot so tells you that the sensation you feel is from the foot. Thus if one of the nerves to the 5th finger is damaged at any point along its length the sensation will be experienced in that finger, similar to phantom pain. This is known as referred pain.

The sensory nerves from the hand, in particular the 5th finger and the outside of the fourth finger are served by the ulnar nerve. This travels along the lateral part of the forearm and behind the elbow, where it is relatively exposed - trauma there often causes phantom pains in the hand so it is often known, at least in Brtain, as the "funny bone".

At the top of the upper arm the ulnar nerve it is joined by the Radial and Median Nerves, like a railway junction in the armpit to form the Brachial Plexus. An even more complex set of divisions then take these nerves into the neck by means of the cervical nerve roots, passing through a dorsal root gangion at the back of the junction between each cervical vertebra. I do not have my anatomy text book in front of me but if memory serves I think this is at the level of the 6th, 7th and 8th cervical roots for the Ulnar nerve.

Interestingly, one doctor found she could affect (stimulate or increase) the sensations in those fingers by . . . pressing down on my head (pressing it downward against my neck). And, as mentioned, applying icepacks to the back of my neck appeared to me to alleviate the pain/sensation, at least on one or two occasions.

To me this suggests that you have a cervical root lesion.

An X-ray will show subluxation of a cervical vertebra or, possibly, a reduced disc space (caused by a large prolapse) but will not show any soft tissue lesion directly.

With the history of whiplash and these clinical findings an MRI may be indicated to exclude a prolapsed cervical intervertebral disc or other soft tissue injury but, as you must know, no doctor can give authoritative advice on the 'net and this is educational only.

I do hope you get sorted soon. I feel it is unlikely to be related to a decompression injury.

:doctor:

 

[bluebanded goby]

Thanks, Paul, for the discussion of the nerve paths and the various merits of X-rays and MRIs. I don't mean to prevail upon you and the others here too much, but this does prompt a couple of more questions in my mind.

I get the impression that one reason my HMO doctor doesn't want to pursue an MRI is because he doesn't feel it would tell him/us very much useful apart from confirming the cause of the symptoms. For example, I gather that it would not be possible to operate on such a cervical lesion to fix it? And knowing the cause wouldn't necessarily help me distinguish symptoms from DCS the next time I experience them?

I get the impression that the hyperbaric doctor, on the other hand, seems to feel that if the MRI reveals a cervical lesion it might tell us something meaningful about whether the lesion causes an increased susceptibility to DCS. I haven't discussed this with him in detail, so I'm kind of improvising here, but I gather that if the lesion looked a certain way he might conclude it was low-risk, whereas if it looked another way he might advise me not to dive.

With this background in mind:

-- Can cervical root lesions be fixed or improved by surgery, rehab or other treatment? Or does one just learn to live with them, perhaps just aiming to avoid further deterioration? If a cervical root lesion is confirmed, what would this tell me from a practical point of view?

-- Would pinpointing the cause help to distinguish such symptoms from DCS? It occurs to me, for example, that if I get arm pain on a dive boat, I might slap a coldpack on the back of my neck to see what happens. On the other hand, if a lesion has created a susceptibility to DCS and there's a bubble sitting there at that very site, simply knowing that the symptoms originate in the neck and improve from being iced doesn't rule out DCS?

Thanks again for the comments; the responses are very educational.