I recently wrote an article for MedBridge, entitled “Diagnosing Hip Osteoarthritis using Clinical Features”. I have attached the column below but you can also access it here, which includes examples of clinical tests and 3D model library. If you are looking for further clinical education units from the comfort of you home, be sure to check out this opportunity. Over 100 courses for a year for the price of a plane ticket. And if you like me, use my name: inTOUCH.
J Wilson and M Furukawa recently released an article in the American Family Physician journal in January 2014 entitled, “Evaluation of the Patient with Hip Pain”. In the abstract they state, “Clinical examination tests, although helpful, are not highly sensitive or specific for most diagnoses; however, a rational approach to the hip examination can be used.”
I definitely agree with the aforementioned remarks, as this is true in all aspects of musculoskeletal differential diagnosis. As physical therapists, we perform differential diagnosis daily, and even though we mainly provide a functional diagnosis, we can assist in determining a medical diagnosis. Contrary to medical physicians, we do not have the capabilities of having radiography or magnetic resonance imaging handy. Through a reasoned clinical decision making process, we can utilize evidence to assist in our judgment call concerning clinical features instead of radiographic features.
As Ben Hando, PT, DSc, OCS, FAAOMPT reveals in his presentation, “Hip Osteoarthritis: An Evidence-Based Approach” on MedBridge, if a patient meets all 3 variables for either variable set listed below, then the positive likelihood ratio of having hip osteoarthritis is 3.44.
Test Cluster 1:
- Pain reported in the hip
- < 115 degrees hip flexion ROM
- < 15 degrees hip IR ROM
Test Cluster 2:
- Pain with hip IR ROM
- < 60 minutes of morning stiffness
- > 50 years of age
Even though the symptoms and variables come from a study over 20 years ago (Altman et al 1991) and also seem to be elementary in regards to differential diagnosis, this criteria is still used by the American College of Rheumatology to categorize patients.
A more recent clinical prediction rule was developed by Sutlive et al in our own JOSPT in 2008 (Sutlive et al). Using the criterion standard of a standing anteroposterior radiograph of the pelvic radiograph, the authors set out to determine which clinical examination findings were most diagnostic of hip osteoarthritis. They found that if 4 of the 5 variables were present, the positive likelihood ratio is 24.3, increasing the probability of hip osteoarthritis to 91%.
The 5 variables are:
- Self-reported squatting as an aggravating factor
- Scour test with adduction causing groin or lateral hip pain
- Active hip flexion causing lateral pain
- Active hip extension causing hip pain
- Passive hip internal rotation less than or equal to 25 degrees
Even though the latter study has a much more favorable positive likelihood ratio that can yield higher post-test probability of hip osteoarthritis being the diagnosis, you have to keep in mind that the Sutlive study had a very small study sample size (n=72), and this clinical prediction rule has not been validated.
Just as Dr. Hando acknowledges in the presentation and I see personally in my clinical practice, a hallmark finding is the lack of hip internal rotation. As you can see, this is a variable in both of the aforementioned studies too.
Even though there is currently no significant supportive evidence to help make a true clinical diagnosis of hip osteoarthritis, we can utilize these clinical features to assist in making a bolder, evidence-informed decision to our healthcare counterparts. This can cut down on imaging costs and reduce unnecessary procedures.
What are some diagnostic features that you see with patients whom you suspect have hip OA? Do you agree with the research noted above?