MEDICAL FAQs

QUESTION

ANSWER

You sure can.

As you say you have full power and ability in the hand. So you can use it to dump, fiddle with a loose weight belt, and do that fine finger co-ordination needed to pull the last of the snot from your nose after a dive.

Make a note of the sensation loss in the hand, and if ever you end up having a rapid ascent then tell the dive doc you had it anyway as it is a classic bend symptom. You don't want 5 unnecessary hours in a pot due to over enthusiastic diagnosis.

QUESTION

ANSWER

It's a pretty major operation you have had there, but one from which you should make a good recovery and be able to dive again soon. I would say that you need to talk to your orthopaedic surgeon about exactly when you should go back into the water. But as a rough guideline people usually regain full function after 8 to 10 weeks post operation. I think you should wait this long but you also need to really work on your thigh muscles to get them as fit and strong as possible. Obviously the key here is when you are finning, and I think you should stay well away from strong counter current dives as you may experience problems there. It would also be a good idea to get the best set of fins that you can get as these can really help you if your knees are weaker than before. As you describe yourself as overweight, you really must loose as much weight as you can. Your new knees can only take a certain amount of wear and tear and so the less weight you have going through them then the longer they will last, and besides that if you are too overweight you shouldn't be diving.

As for whether you are more prone to a bend in the knees, well as they are now made of metal you wouldn't really be able to tell. However in the area surrounding the replacement, as the operation may have slightly affected any tiny capillaries then there is a theoretical risk that it may be harder for any nitrogen to be transported away so again, always dive well within tables. I don't think you need to restrict your depth of diving to any particular level but you should only dive as deep as you are qualified to. Another very important point to note as well is that one of the side effects of this operation is that a nerve called the common peroneal nerve can get damaged. This can be told by a lack of sensation above the instep of your foot and it is worth noting this as if ever you are suspected of having a bend the doctor may feel this to be an important symptom of DCS and end up putting you in the chamber, whereas if the doc already knew this was present it could save you a 5 hour decompression!

Finally I would add that on long flights you may have a greater chance of getting a clot in your legs, i.e. a deep venous thrombosis so always stay well hydrated and take a walk down the aisles every hour or so to prevent this.

QUESTION

ANSWER

You'll be fine. An arthroscopy is fairly weedy in the scale of ops you can have in our fine hospitals. It's more investigative rather than operative. A little nick, and then a steel rod into your knee, so the orthopaedic surgeon can have a gander at your cruciates and menisci. It causes little damage so a dry pot dive is fine.

It is worth noting here though that damage and scarring to areas of your body wont necessarily invoke a bend at depth, they may off gas slower, but they on gas more slowly too. All even at the end of the day.

QUESTION

ANSWER

Oooh, I think I can think of plenty of different exercises to get the heart rate up, that wont mess up your knees any further.

One of my favourite patients, a certain Nigel Band, well known to the tecchie Trimix rebreather-mongers amongst you, in fact invents his own exercise each year.

As long as the heart rate gets to the max predicted, and comes down to normal when it should then I don't really care if you do head stands, ride a bike or press up like a Latino lover who has been told he has a week to live.

A word of caution though, is that if your knees do stop you from finning properly, or dragging a bent diver out of the water, then look closely at DM'ing, as you are the support man for for the trainees around you.

QUESTION

ANSWER

Awesome, 14 weeks with your leg at various comedy angles. I suppose that’s 2 months wheelchair-bound, 3 in metamorphosis, and the last 4 apologising to people on the Tube as they feel that naughty bump on their butts as you turn. Bad luck mate, I will avoid the same by remembering to do no physical activity from now on. Here’s to potatoes and my couch.

Anyways, once it’s better, your knee will be as good as new. Dive with the best ergonomic fins when the physio gives the OK, and as for the HSE medical, there are alternatives to the steps to get your heart rate up. A tax demand, parking tickets and Ken’s C charge will do that. Or we could give you a lower step for longer. Either way you will be Instructing.

QUESTION

ANSWER

It’s a functional thing. If your elbow is able to bend to do all those divey things, like putting on the kit, launching the SMB, reaching for the up or down button on your BCD, then go for it. However if there is gross limitation of movement, or pain, forget it. The elbow joint, where the radius and ulnar articulate with the bottom of the humerus, is all held together by a fibrous sac called a bursa. Inflammation here will fill up the sac with fluid, and cause this olecranon bursitis. Normally it looks like your elbow has grown an apple in it. That’s the fluid. I hope your doc has stuck a needle in and drained some of it out, as that speeds healing up. But for now stick with the ibuprofen, wear a tight elastic support stocking-like thing on it to prevent any more fluid build up, and enjoy your festive-fun-dive.

Sounds cremasteric reflex inducing to me. What’s that? Guess, no prize for the winner.

QUESTION

ANSWER

We should re-christen this “medial epicondylitis” (to give it its true medical name) as “Tank Lifter’s Elbow”, you’re right. This is one of those perennial diving concerns, which seems to stem from many anecdotes of recurrent symptoms in previously injured areas of the body. I have to say that I’ve yet to see any convincing evidence that DCI is more likely at the sites of old trauma or scarring. That said, I do not dismiss the fact that many divers seem to get aches, pains and odd sensations in areas of prior damage. Quite why this happens is a bit of a mystery.

It is likened in a way to the old granddad whose arthritic knees begin to play up just before rain. In the ‘60’s a rheumatologist called Joseph Hollander built a special climate chamber to investigate this phenomenon, and found that what was previously thought to be an old wives’ tale was a demonstrable clinical reality. The currently favoured explanation goes like this: uninjured tissue is relatively elastic, compared to scar tissue, which is stiff, fibrous and dense. Hence pressure changes will cause expansion and contraction in healthy tissue, allowing gas to diffuse as normal. The scar tissue in old injuries distorts and is pulled about, often causing pain and inhibiting the easy movement of gas. As a consequence, one could postulate that once nitrogen is taken up by scarred areas, it lingers and increases DCI risk. A nice theory, but one not supported by experiments so far.

The bottom line then, is that we don’t really know whether this connection between scar tissue and DCI exists. It’s probably safe to say that in small areas, for example broken digits, healed cuts etc., there’s little to worry about. When we’re talking major surgery though, especially that around regions prone to DCI anyway (eg. spinal operations), it might be prudent to take a few extra precautions with regards to conservative diving – minimising bottom depths and times, using Nitrox, keeping profiles square and avoiding deco where possible.

QUESTION

ANSWER

Another issue, another eponym… Kienbock was an Austrian radiologist who first described breakdown of the lunate, a moon-shaped bone in the wrist. The precise cause is unknown, but it’s rare and most likely a complication of trauma. The initial injury can be innocuous (even a mild sprain can lead to so-called “avascular necrosis”, where the bone dies as its blood supply is interrupted). Pain, stiffness and swelling are the most common symptoms, which eventually start interfering with manual dexterity. At this point surgeons generally intervene, although quite how is controversial (surgeons in my experience don’t agree on much).

As I explained last month, there is some anecdotal evidence that DCI occurs more often in previously damaged or scarred tissue, but there is no scientific data to back this up that I am aware of. So as long as the Kienbock’s does not impair you functionally at all (in terms of the use of your hand), I’d say you could dive safely with it. Similarly this would be the case with the ankle chip and the knee – if you’ve had no problems in the recent past, then finning should not cause a further dislocation.