About Orthopedic Manual Testing Method
Sensitivity, specificity, positive/negative predictive value, etc. of manual testing methods
First of all, there is no such thing as a "perfect" orthopedic manual examination that can determine 100% of the pathology.
This examination should not be performed in the dark, but only as necessary.
However, medical professionals who do not fully understand the usefulness of tests often judge that a positive finding = abnormality, and it is necessary to know about the sensitivity and specificity of various tests when conducting them.
What is sensitivity?
Sensitivity is one of the indicators of the diagnostic performance of a test, and it indicates how little "oversight" there is.
It refers to the percentage of patients with a given symptom who are considered "positive" by the test, also known as the "true positive rate.
A highly sensitive test does not test positive or negative based on the presence or absence of symptoms.
"Both people with and without symptoms are likely to test positive.
In other words, they are less likely to test negative.
In other words, it's less likely to be negative, and a negative result can rule out the disease.
What is specificity?
Specificity is a measure of a test's diagnostic performance, and indicates how little overdiagnosis there is.It refers to the percentage of negative test results in a healthy person without symptoms.
In a highly specific test, only people without symptoms are considered negative, not people with symptoms who are considered positive.
It means that both people without symptoms and people with symptoms are likely to test negative.
Therefore, if you get a positive result on a test that is unlikely to be positive
If you get a positive result on a test that is difficult to test positive for, it is highly likely that you have the disease.
Positive and negative predictive value
The positive predictive value is the probability that a patient with a positive test result actually has the disease.
The negative predictive value is the probability that a patient with a negative test result does not have a disease.
Positive predictive value (PPV)
The probability that a patient with a negative test result will not have the disease.
Pre-test probability and post-test probability
The pre-test probability is the probability that a person is expected to have the disease before the test is performed.
It is sometimes understood to indicate the prevalence of the disease, but it is limited to cases where there is no information and no experience of the examiner before the test.Therefore, the situation where the pre-test probability is higher is based on the information obtained by interviewing the patient before the test, combined with the experience of the examiner.
If the pre-test probability is high, the positive rate will be high; if it is low, the positive rate will be low.
The post-test probability is the probability that the results of the test indicate the presence of a particular disease.
Likelihood ratio
The likelihood ratio indicates how much more likely it is that a person with a disease will get a test result than a person without a disease.
It expresses the "likelihood" of a positive or negative finding.
The positive likelihood ratio is calculated as the ratio of the likelihood of a positive result in a person with the disease to the likelihood of a false positive result in a person without the disease.
The higher the positive likelihood ratio, the greater the likelihood that a positive test result will confirm the presence of the disease.The negative likelihood ratio is calculated as the ratio of the likelihood that a person with the disease will test negative to the likelihood that a person without the disease will test false negative.
The closer the negative likelihood ratio is to zero, the more likely it is that a negative test result will rule out the presence of a disease.
Precautions to be taken when performing the test
(1) Most of the tests induce symptoms, so it is necessary to explain them well in advance.
(2) Do not use too much pressure or force.
(3) Do not make any diagnosis (except by a doctor)
(4) Practice sufficiently and receive guidance from skilled personnel before performing the procedure.
Explanation
(1) If the procedure is performed without explanation, the symptoms may worsen, and in the worst case, a medical lawsuit may result.
This is not limited to testing methods, but consent should be obtained after sufficient explanation.
(2) In this method, pressure or force is applied directly or indirectly to the relevant part of the body in order to clarify the problem occurring in the target tissue or other parts.
If the pressure is too strong, there is a risk of inducing symptoms and damaging the tissues more than necessary.
And many mechanical stresses are applied in a transitive manner, so that the examiner fully understands that there is a possibility of injuring the patient.
(3) Only a physician can make a diagnosis, and even if other qualified medical personnel perform manual examination methods on a patient, the diagnosis of "XX is a disease" or "XX is not a disease" is a violation of the Medical Practitioners Act.
This is a violation of the Medical Practitioners Act. In Japan, only licensed physicians are allowed to make diagnoses.
(4) The examination method itself is often mechanically stressful, and without sufficient practice, it can cause tissue damage, not to mention inappropriate test results.
If you do not practice enough, you may damage the tissue, let alone get proper results.If you are not in such an environment, don't do the test! However, it is necessary to fully understand the purpose, methods, points, and possible mistakes of each test method.
