Carpal Tunnel Syndrome: How To Diagnose Yourself in 6 Easy Steps
Welcome back to this mini-series on carpal tunnel syndrome (CTS for short).
If you missed my first article exploring what exactly carpal tunnel syndrome means, you can find it here. To build on this, today we will hit hard on this idea of empowering you as the patient. I’m actually going to teach you how to diagnose yourself with CTS.
Or at least get a pretty good idea of the chances you have CTS.
Carpal Tunnel, Carpal Tunnel Everywhere
By far the most common condition I’m asked about, whether at the office or a cocktail party, is carpal tunnel syndrome. “Carpal Tunnel” might as well be the buzzword of my professional life. You’d think it’s an epidemic.
And yet, I believe some of the reason I hear it so often is due to the public’s collective use of CTS as a blanket term. In the eyes of many, any hand or wrist symptom is casually referred to as ‘Oh, that’s my carpal tunnel.’
On the contrary, CTS is actually a very specific and straightforward set of symptoms.
While it is definitely common, it’s not as ever-present as you may think. I will spare you the details, but there was an important 2008 research study [1] that demonstrated just 6 signs and symptoms of carpal tunnel syndrome that were as effective at diagnosing CTS as were the ‘fancy doctor tests’ (ie, electromyography and nerve conduction studies) we often use to confirm the condition in our patients.
And the best part? You can test for all of these at home with a little help from a friend.
So.
Before you use valuable PTO to take off work, wait on long phone holds to schedule with a doctor, or rack up bills against your insurance deductible, let me help you put on your own doctor hat to see if you have CTS [2].
Grab a pencil to jot down your ‘score’ as we walk through these 6 steps:
1. Symptoms primarily in the thumb, index, and middle fingers
We won’t belabor the anatomy here (we do here), but the nerve pinched in carpal tunnel syndrome is the median nerve.
This nerve has a very specific job in the hand. It (1) provides strength to some thumb muscles and (2) transmits sensation from the palm side (not the back side) of the thumb, index finger, middle finger, and part of the ring finger.
This is a subtle but crucial point. Pay attention to which of your fingers actually feel numb. So many patients tell me ‘Oh, my whole hand goes numb.’ That might be true but if it is true, then you have much more going on than just CTS (more on that here)!
And the pinky finger is the key. Take the time to really focus — if you feel symptoms on the palm side of your hand with the exception of your pinky finger, then slam dunk! It’s probably carpal tunnel syndrome.
So to review…do you get numbness, tingling, or burning predominantly in the thumb, index, and middle finger? Assign yourself 3.5 points.
2. Nighttime Symptoms
While symptoms can absolutely be bothersome during the day, carpal tunnel is notorious for being worse at night.
In fact, take a moment to look at the last seven days of Google search trends (below). Notice the spikes? Those spikes are Google searches for “What is carpal tunnel” and “hand numb” from 12am-3am every night. People are literally waking up with their hands numb and asking Google about it.
So if you have hand numbness that wakes you up at night, give yourself 4 points.
3. The Phalen Test
Funny name but easy test.
Place the backs of your hands together (see Figure 1) and hold that position for 45 seconds. If you notice shooting pains, numbness, tingling, or burning on the palm side of the thumb, index, or middle fingers, give yourself 5 points.
Figure 1 - The Phalen Test
4. The Tinel sign
Tap yourself with medium force up and down your wrist (see Figure 2) in the region shown. If this causes numbness, tingling, burning, or shooting pain to your thumb, index, or middle fingers of the hand, give yourself 4 points.
Figure 2 - Where to tap your wrist to evaluate for a Tinel’s sign.
5. Loss of 2-point discrimination
This may be the most difficult one to do at home (you’ll need a friend and a paperclip), but you can do it.
Bend the paperclip like so (picture/video). Use a ruler to ensure the exposed ends are 6mm apart (picture). Then hand the paperclip to a friend and close your eyes. Your friend should lightly push the paper clip against different fingers, changing whether they use one or two ends (picture). Your task is to correctly identify whether you feel one or two ends.
If you cannot distinguish the difference, give yourself 4.5 points.
6. Muscle atrophy or weakness
If you look at your palm, you’ll notice a large bulk of muscles at the base of the thumb (see Figure 6). These are called your thenar muscles and they are powered by the ‘carpal tunnel’ nerve (the median nerve). If these feel weak or have shrunk (atrophied) compared to the other side, give yourself 5 points.
In fact, if this is the case for you, get yourself immediately to a hand surgeon, as your carpal tunnel may be severe. This is not a symptom to mess around with.
Figure 6 - The thenar muscles of the thumb. These muscles are powered by the median nerve
Putting It All Together
Congratulations! You just worked through diagnosing CTS to the same level as a hand surgeon.
Now it’s time to add up your score. Please remember that very few diagnoses in medicine are black and white. Instead, most are based on the probability that you do or do not have a condition. For CTS, we know:
If your score is greater than 12, you have an 80% probability of having CTS
And that’s it. Now you know the likelihood that your bothersome hand and wrist symptoms are truly from CTS versus something entirely different. If your results indicate you may have CTS, read on to learn more about the condition and what I recommend for treatment (here).
And if you have any doubt whatsoever, please get yourself to a hand surgeon for evaluation, as nerve damage from CTS can become permanent.
References:
[1] Graham, B. The Value Added by Electrodiagnostic Testing in the Diagnosis of Carpal Tunnel Syndrome. The Journal of Bone & Joint Surgery 90(12):p 2587-2593, December 01, 2008. | DOI: 10.2106/JBJS.G.01362
[2] Graham, B., Regehr, G., Naglie, G., & Wright, J. G. (2006). Development and Validation of Diagnostic Criteria for Carpal Tunnel Syndrome. Journal of Hand Surgery. www.jhandsurg.
