Tuesday, September 6, 2011

Reading Your Own X-Rays

As triathletes, we often sustain injuries requiring some form of medical imaging to arrive at a diagnosis and a treatment plan.  The images will most often start with X-Rays, which if inconclusive may be followed by an MRI or CAT-scan, or on rare occasions a bone scan.  We then get a diagnostic pronouncement from our doctor, complete with hand-waving and finger-pointing in the general direction of the medical images.

The sad fact is, doctors are occasionally wrong, or at least not "completely correct".  I have personal experience with this.  Most often, they simply leap to a logical conclusion, a natural by-product of having only a 15 minute appointment to work with.  Other times they are "almost-right" or "right enough", and the prescribed care is adequate for the actual injury.  But sometimes "close" is not good enough, and much time can be lost pursuing ineffective treatments.

You should view your doctor as being an educated and dedicated professional, though one who is operating under lots of time pressure, who also is only human. The best way to improve your outcome is to be able to help your doctor as much as possible, to be able to help gather symptoms, to help analyze them, and to help find the best remedy.  A second way, of course, is to always get a second opinion before doing anything major like harsh drugs or surgery, or after an initial treatment fails.

If you had an extra 8-10 years, you could become a doctor yourself.  Well, for at least one specialty, if not for all the specialties involved with athletic injuries.  However, just because the knowledge mountain is truly huge, that does not mean there isn't lots of valuable and useful medical knowledge each of us can and should learn and learn to use.

The best place to start is with "A&P": Anatomy and Physiology.  Being able to name the parts of your body, know what they do, and know how they fit together.  While it may be interesting and fun to learn the whole body, the easiest and most useful way to start is with the specific areas of recent injuries.  And most of our pain and injuries tend to be in the legs and feet.

When studying a portion of the body, it is good to start from the inside and proceed outwards, starting with the bones and cartilage, then the ligaments, then the muscles and tendons, and finally the nerves.  But even that is a large amount of information.

So, rather than learn everything about even a single body region or subsystem, we can start by taking advantage of a fundamental property of our bodies: We have bilateral symmetry.  If we hurt on one side, the other side will likely be an excellent reference for comparison.  Instead of learning all about the injury area, we can start by looking for things that differ between the two sides.

When making comparisons, our eyes are our best sensors.  When looking inside our bodies, X-Rays give our eyes lots to work with.

A possible first step in this direction is to learn what your doctor is doing when ordering X-Rays.  A typical order includes the name of the body part and descriptions of the desired views.  But this is also quite a lot to learn: Most doctors don't remember the names of all the possible views, and tend to work from multiple choice lists.

What I do instead is simply request that the same exposures be taken on both sides of the body. This way, no matter what the exposures are, I will be able to compare the same views for two body parts: One injured, and one (presumably) healthy.
 
Many doctors will automatically order X-Rays for both sides, or will gladly do so if asked.  If the doctor won't order the duplicate exposures (citing issues of necessity, cost or radiation exposure), I've sometimes been able to convince the X-Ray tech to image both sides at once on a single plate (same number of shots).  The doctor may not need the additional images, but I sure do!

After the appointment, get a copy of the X-Ray images downloaded onto CD or DVD (a minor charge, if any, though there may be some paperwork).  I recommend waiting until after a radiologist reads the X-Rays, since his report will typically be included with the X-Ray data.

Next, you get to play Home Radiologist!  There are several free/open programs available to help you examine your X-Ray images (opening DICOM files, zooming, contrast stretching, pseudo-color enhancement, etc.).  You may need to try several programs before finding one that you are comfortable learning and using.

Before looking for any specific conditions, start with getting used to playing with X-Rays.  Most of the above programs include tutorials to help you learn your way around X-Ray images.  There are also several tutorials online that will teach you about what you can find by examining an X-Ray, though most of these tutorials are aimed at medical students, and are thus written in 'medglish' (Medical English: English with lots of Latin and Greek thrown in).

Next, learn the anatomy imaged by the X-Rays.  Much can be learned while viewing an X-Ray alongside a good anatomical reference (I use the images in Wikipedia and WebMD).  There are also many online sources for reference X-Ray images, such as MedPix.  Use these for practice until you get your own images.

Another great resource is your dentist.  Most of us get dental X-Rays taken twice each year, so there is lots of history, redundancy and variety to work with.  Most dentists are more than happy to share how they examine your images, and explain what they find.  My dentist and I have an ongoing contest to see if I can spot everything that's going on before she reads my images.

It can take many hours to 'train our eyes' (train our visual perception system) to 'see' (search for and find) subtle variations in X-Ray images.  Having lots of images to examine really helps, especially multiple views of the same part on both sides of the body.

I have well over a decade of my own X-Ray data for my back, knees, ankles and feet.  (Yeah, I'm getting older, and my X-Rays prove it.)  These images get more valuable not only with each passing year, but also with each new injury.

Three years ago I had knee pain that was diagnosed as being caused by ITB Syndrome, and a stretching regimen was prescribed.  My Sports MD also took X-Rays of my knees to ensure there was no other damage.  The nurse pulled the images up on a display, and while I waited for the doctor to return I correctly identified my own chondromalacia.

I didn't know that was what it was called at the time, nor what caused it, but I knew enough about X-Rays and basic knee anatomy to able to quickly spot the differences between the X-Ray images of my two knee caps, and to associate that with both my pain and the range of motion over which the pain occurred.

This skill really paid off for me very recently.  I had initially injured my foot last October, and everyone I talked to, including my MD, said it appeared to be a stress fracture of the second metatarsal.  X-Rays showed nothing, which is not unusual for first-time stress fractures.  And, sure enough, 6-8 weeks later I was able to gently return to running.

In a recent triathlon I again experienced sudden pain in the same place, but with less than half the intensity I had in October.  I decided to finish the race, with the commitment to immediately quit if the pain increased to its prior level.

Two days later I was back with my MD, who ordered more X-Rays.  To our mutual surprise, not only was no new break visible, but I immediately saw there was no hint of the bone thickening expected from the healing of the prior stress fracture.  We had a bona-fide mystery on our hands, and we decided to call in a specialist.

My MD gave me a referral to a podiatrist, who then diagnosed a problem with my transverse metatarsal ligaments (the ligaments that cross the foot connecting the heads of the metatarsals).  He confirmed that I had never had any significant stress fractures in either foot.  Fortunately, the treatment and recovery for both injuries is nearly identical (don't run, avoid causing pain, wait 6-8 weeks).  I'm in another recovery phase now.

The lesson here is that many physical ailments don't show up on X-Rays, so it is important to know not only how to look for damage, but also to know to look for expected characteristics that are missing.  Either way, learning your way around an X-Ray is valuable.

While few will likely want to get this involved in analyzing their own medical data (yes, I am an engineer), I do highly recommend everyone become comfortable viewing their own X-Rays, and not be afraid to say "Show me!" whenever a diagnosis is made from the X-Ray data, to typically be followed by asking "Where?", "Why?", "How?" and so on.

If you do get involved with reading your own X-Rays and decide to look at an MRI, you should know that MRI images are at least 10 times harder to analyze and interpret.  Even specialists have trouble with them, and recent studies have shown MRI to sometimes be a relatively poor primary diagnostic tool, and it has been shown to be almost useless for correctly diagnosing sources of back pain (leading to needless surgery that harms or fails to help the patient).  So be very wary when your orthopedist uses an MRI to justify a surgical remedy!  Ask if the same recommendation would be made without the MRI images, and insist that additional imaging be performed (X-Ray, CAT-scan, bone scan, ultrasound, etc.) before consenting to surgery or other risky or costly treatments.  And, of course, always get a second opinion.

You are the one who has to sign your treatment consent forms.  You have to go through the treatment.  You have to deal with the after-effects.  You are fully responsible for what is done to your body!  It is important that you learn as much as possible about the entire diagnosis and treatment process, and never blindly trust doctors (or anyone else).  The more serious the injury and/or the more drastic the treatment, the more vital detailed knowledge becomes.

X-Rays are a nearly universal diagnostic tool for finding and identifying structural damage.  Your doctor will order them either to confirm a specific diagnosis, and/or to exclude other possible problems.  Either way, the more you know, the sooner you will start the correct treatment.


I have not included any of my own X-Rays here, nor have I described the specific things I do to examine them.  This is intentional:  I want to avoid giving the false impression that I am any kind of an expert when it comes to interpreting medical X-Rays.

I am not a medical radiologist, though I do have extensive experience with industrial radiographic imaging.  I have developed several industrial imaging systems, and have trained operators in their use.

I am more than willing to list the tools I use and how I use them, but a blog post is not the best forum.  If you'd like a demo, please say so in the comments or contact me directly.  If you are local, I'll put together a small seminar.  If not, I'll try to learn how to make a YouTube video.