Ross Hauser, MD
The challenges of diagnosing upper cervical instability with MRI or standard physical testing are documented in medical research. BUT, the research is very limited. This is not a frequent area of study for doctors and radiologists. So let’s explore what we have.
In December 2013, a paper in the journal Physical Therapy (1) offered these observations:
“Patients with neck pain, headache, torticollis, or neurological signs should be screened carefully for upper cervical spine instability, as these conditions are ‘red flags’ for applying physical therapy interventions. However, little is known about the diagnostic accuracy of upper cervical spine instability tests.”
To try to answer this problem the research team examined the diagnostic accuracy of upper cervical instability screening tests in patients or people who are healthy and in which sensitivity (the probability that these tests could correctly identify upper cervical instability and specificity (no test is 100%, the specificity is the percentage of tests that are likely accurate) were reported or could be calculated. So, in essence, could the tests correctly identify upper cervical instability (percentage of sensitivity)? How accurate would these tests be, specifically? So specificity would be the percentage of tests that would be considered an accurate diagnosis.
What were the tests?
- Sharp-Purser Test (SPT) to assess for atlantoaxial instability. Mostly in patients with rheumatoid arthritis. This is a controversial test as its safety and reliability are often questioned. This was discussed in a May 2020 study in The Journal of Manual & Manipulative Therapy (2) where researchers noted: “The Sharp-Purser Test may be inappropriate to use due to inconsistent validity, poor inter-rater reliability, and potential to cause harm.”
- Clunking test – does the patient make a clicking or clunking sound when they move their head?
- Palate sign – deviation of dysfunction in the palate.
- Alar ligament test
- Transverse ligament test
- Tectorial membrane test. You had your head pulled on, and if symptoms worsen or are relieved. If they are worsened, upper cervical ligament weakness or instability is suspected, with a focus on the tectorial membrane, the continuation of the posterior longitudinal ligament that covers the Odontoid process.
- and posterior atlanto-occipital membrane test.
The researchers then assessed five previously reported studies. Problems developed.
- Statistical pooling was not possible due to clinical and statistical heterogeneity. (A general opinion could not be given because there was insufficient common data.)
- The specificity of 7 tests in the five studies was sufficient, but sensitivity varied. (The outcomes specific to people with ligamentous cervical instability had enough data to examine, BUT the sensitivity did not.)
- The Predictive values were variable. Likelihood ratios also were variable, and, in most cases, the confidence intervals were large. (Confidence intervals mean a predetermined set of values that would help confirm the accuracy of the tests. The researchers said it was too large. What does this mean? For example, say there was a test that tried to determine the likelihood that a certain shoe size caused toe pain. If the confidence intervals were size 2 to size 15, it would cause toe pain, which is really not helpful, as it could be suggested that all shoe sizes cause toe pain, and the test to see if size 7 causes more pain than size 9 would be difficult to determine or even pursue as a valid finding in this example.
The general conclusion was that these tests may be accurate; they may not be. It is difficult to tell based on the data examined.
At Caring Medical, we understand that accurate diagnosis is the cornerstone of effective treatment. Our state-of-the-art diagnostic center is equipped with advanced technologies to precisely identify the underlying causes of your condition, guiding you towards a tailored, effective treatment plan.
We focus on dynamic diagnostics instead of the way standard MRI, CT, and X-rays are performed, where a person is lying down or perfectly still. Testing a patient while they are in motion, upright, and while they hold positions and do maneuvers that are more likely to trigger symptoms means we can find if ligamentous joint instability is the underlying cause of the chronic disabling symptoms in real time!
More information
References
1 Hutting N, Scholten-Peeters GG, Vijverman V, Keesenberg MD, Verhagen AP. Diagnostic accuracy of upper cervical spine instability tests: a systematic review. Physical therapy. 2013 Dec 1;93(12):1686-95. [Google Scholar]
2 Mansfield CJ, Domnisch C, Iglar L, Boucher L, Onate J, Briggs M. Systematic review of the diagnostic accuracy, reliability, and safety of the sharp-purser test. Journal of Manual & Manipulative Therapy. 2020 Mar 14;28(2):72-81. [Google Scholar]