Differential Diagnosis
What is a differential diagnosis?
Differential diagnosis is the process of differentiating a condition or disease from others that have similar signs and symptoms. It’s been a big theme this semester at school. We are often given a case to study and work through. A super simplified version can look like this:
A 65 year old male walks into your clinic for a follow up visit after having rotator cuff surgery. He complains of having a sudden, severe headache yesterday. Today, he is sleepy, has a stiff neck, and has difficulty focusing his eyes. His blood pressure when sitting is 135/92. His medical history consists of 2 full knee replacement surgeries, an aortic aneurysm, and drinking alcohol weekly. His current medications include over-the-counter ibuprofen as needed and daily Propranolol.
Photo by Kindel Media from Pexels: https://www.pexels.com/photo/close-up-photo-of-a-man-having-a-neck-pain-7298867/
We students could be asked a bajillion questions from this much information but the two most notable ones for right now would be:
What do you think is your primary diagnosis, given this information?
What is your differential diagnosis?
There can be multiple answers to the second question but we try to have one in mind that makes more sense than others. A few other questions we might be asked are:
Is this patient’s stiff neck related to his surgery?
How do his medications affect your diagnosis?
Is his history of drinking alcohol weekly significant to this visit?
Is this a non-emergency, emergency, or urgent concern?
Is it safe to treat this person right now?
Does your primary diagnosis make sense for this individual’s age?
Photo by Ivan Samkov: https://www.pexels.com/photo/person-holding-pen-writing-on-paper-4989141/
Why are you learning this to be a physical therapist?
We are spending a lot of time learning how to identify a lot of conditions and diseases that we can’t treat. Neurological conditions, heart problems, kidney disease, allergy-related illnesses, long-term, short-term, and all the things inbetween. It’s wild. And you know what? We can’t officially diagnose these things when we officially become physical therapists. I could see that someone is showing every sign and symptom for Wilson’s disease or syringomyelia but I won’t have access to the tests that can be used to officially diagnose them so I cannot tell that person “You have syringomyelia.” I also won’t have enough of the specific type of education or training to formally diagnose conditions that aren’t primarily movement-related.
What I will be able to do when I become a licensed clinician, besides diagnose movement-related conditions, is make the best decision possible about what to do next. I don’t think it’s any secret that our (American) healthcare system is expensive and frustrating and difficult to navigate. For most people, they will have to take time away from work or other plans to be able to come see me. They’ll have to deal with insurance and try to figure out how many doctor’s visits they can afford and which doctors they can go to. Physical therapists have a doctorate level education so they can make sure you stay as safe as possible and to cut out as many middle-people as possible.
Photo by Pavel Danilyuk: https://www.pexels.com/photo/doctor-in-white-lab-coat-sitting-in-front-of-little-girl-and-listening-5998443/
Obligatory disclaimer: Nothing on this blog or post should be used as a substitute for medical advice. The case study I provided is a quick example that I threw together so I could share a sample of what PT students are learning these days and should not be used to make medical decisions.
The person in my case study above? They’re showing signs and symptoms that could indicate they’re having a subarachnoid hemorrhage. This would be an emergency, requiring a 911 call, and also means that it may not be safe to do PT with this person at this time. If you require care from a different doctor, a physical therapist should be able to refer you to the right kind. Human medicine is incredibly specialized now and for many people, running around trying to find the right specialist takes too much time, is incredibly frustrating, and can have serious consequences. It might be nice to have someone in your corner that can save you some of the run-around, yeah?
Rehabilitation providers also play a special role in healthcare since they tend to see their patients more frequently and for longer periods of time than many physicians. This means they’re more likely to be around a patient when they’re experiencing unfamiliar signs and symptoms, so it’s helpful for them to know enough to help their patient get to the right place faster.
I know this photo looks a little homey if you’re expecting a more clinical setting. Did you know that physical therapists can work in home health settings?
Photo by Alex Green: https://www.pexels.com/photo/black-patient-and-psychologist-discussing-problem-in-office-5699451/e.
If you learned anything new from this post, I’d love to know what it is in the comments below! This one was a little long compared to others - thanks for hanging in there until the end!
