Critical Thinking For A Deep Vein Thrombosis
He came in complaining of extreme calf pain.
Everything seemed pretty straightforward, health history seemed fine, no real mechanism of injury, but it just seemed odd.
I tried doing the Homan’s sign orthopedic test but honestly couldn’t tell if I got a negative or a positive result because neither seemed very clear.
After three treatments it didn’t seem to be getting much better. We made an appointment for the following week but he didn’t show up, I kind of freaked out a little.
Did he have a DVT and I missed it?
I’ve only seen a case like this a couple of times and honestly to this day am not sure if I have ever done the orthopedic test properly because it never seemed really clear each time I tried it.
Deep Vein Thrombosis
If you’ve never heard of it, or are not sure what I’m talking about when referring to a DVT, it stands for “Deep Vein Thrombosis,” which is the formation of a blood clot in the lower limb.
The big issue with this is if the clot dislodges it can become a pulmonary embolism blocking blood vessels in the lung, which, depending on the size of the clot could be life-threatening. If it is a smaller size clot, at a minimum it can cause damage to the lungs.
So, how do we know if this is what our patient has when they come in complaining of pain in the lower legs?
Well, first off we need to get a good thorough health history from the patient. When we look at the causes of a DVT, you could easily ask some questions that would throw up some red flags as an indicator without even observing the area of complaint. Some of the risk factors that cause a DVT include:
- Family history of DVT.
- Overweight or obese.
- Damage to blood vessels:
- broken bones
- severe muscle damage
- during surgery
- varicose veins
- vasculitis
- Conditions that cause blood to clot more readily:
- cancer
- heart and lung disease
- thrombophilia
- Hughes syndrome (an immune disease that causes increased clotting)
- Being inactive or immobile for extended periods:
- Sitting for extended periods on a plane during travel (this is an important one)
- long duration surgeries
- Pregnancy.
- Women on birth control or hormone replacement therapy.
Think about turning all of the above factors into questions during your intake. If your patient reports any of the above it’s a good sign to investigate a little deeper before progressing with your treatment. It is also worth noting, this typically happens unilaterally, so hopefully, only one side is of concern.
If you get to the point of doing an assessment on the painful area some of the symptoms look like:
- Heavy ache.
- Pain, swelling, and tenderness in the area.
- Red, warm skin, especially around the back of the leg close to the knee.
We were taught an orthopedic test in school called “Homans Sign”. From memory, you were supposed to squeeze the gastrocs while the knee on the affected side was bent and have the person dorsiflex their ankle. I have only known two people in my life who have been diagnosed with this, both told me that in their case the pain was so bad, there is no way they would have let someone do that to them (and yes I realize this is anecdotal evidence, but I thought it worth the share).
However, this test has come under some scrutiny lately. One study showed Homan’s sign was positive in 33% of patients with an actual DVT, but also in 21% of the patients who had no thrombosis. The estimated accuracy of the test ranges from 8% to 56% and also positive in more than 50% of patients who were symptomatic but did not have a DVT. So, it’s fair to say this orthopedic test is not a reliable test for us to use.
In researching for this post I came to understand there is also occurrences of upper limb DVT’s, which can affect any veins of the upper extremity or thoracic inlet, including; jugular, brachiocephalic, subclavian, and axillary veins as well as the more distal brachial, ulnar, and radial veins.
Some of the risk factors in this case include:
- High body mass index.
- Pregnancy.
- Surgery.
- Smoking.
- Malignancy.
- Foreign body in the vascular system (more than half the patients who had this, was because of pacemaker).
The more typical signs and symptoms are:
- Swelling.
- Pain.
- Edema.
- Cyanosis.
Some other symptoms like localized neck and shoulder pain, weakness, paresthesia, and elevated body temperature can occur but are less likely.
Yet, another reason why our clinical reasoning has to be used when interviewing our patients. If we see any combination of the above signs and symptoms mentioned for lower or upper limb DVT, we MUST at a minimum refer out to a doctor, but more likely to the hospital to be sure of an accurate diagnosis, and of course to ensure patient safety.
The Skilled Therapist
The whole reason behind this post was because of an article being shared around regarding DVT.
It is the story of a 53-year-old woman who presented to a clinician with worsening shortness of breath, history of smoking and hypertension. Upon further investigation, they found increased calf muscle soreness over the previous two weeks after having an aggressive massage done while getting a pedicure.
After more assessment, it showed defects in several pulmonary arteries and examination of the lower extremity suggested residual deep vein thrombosis.
Fortunately, the article acknowledged that for this story and another one mentioned, the massage was being done by a layperson, not a skilled therapist, and massage was only partially responsible for the outcome.
Now, I get it, we spend a lot of time on this site busting some massage therapy myths, however, this one is no myth. We actually want to reinforce the importance of this message. Note the article points out a skilled therapist was not involved. Well, I firmly believe that if you’ve been following this blog for any length of time YOU are a skilled therapist. Whether this is new information to you or just a review, it’s important to recognize those signs and symptoms and be able to communicate effectively with your patient in case you do need to refer them out because this is a medical emergency and should be treated as such.
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Great post on an important and serious condition. As you point out, the Homan’s Sign test is not reliable and according to Physiopedia, it has low sensitivity and specificity in diagnosing DVT but can be of value if used alongside other accurate diagnostic procedures like ultrasonography etc. If the test isn’t done correctly, i.e the therapist should be passively and abruptly dorsiflexing the foot while the affected knee is fully extended, not the client actively dorsiflexing their own foot, then that may result in an unclear result one way or the other. Also, I found it interesting to discover that the test can be risky because vigorous dorsiflexion of the foot is a method used by surgeons to expel clot from the veins, so we want to be cautious here.
As you say, getting a thorough history, assessment and consideration of risk factors is critical and if in doubt – refer out. We do much better by our clients when we do that. Even if it turns out it’s not DVT, it may be something else previously undiagnosed, and our clients will be grateful for our due diligence.