When is Central Sensitization a Factor in Knee Osteoarthritis?
I remember reading an interesting tale quite a few years ago. The story was about a grandma who attended a field trip to a local university research laboratory with her grandson. Picture a large machine that when placing your hands into it would project an image of the hands like what happens at fairs and amusement parks with the image distorting mirrors. The grandma wanted to participate in the experiments with her grandson.
Imagine that when she placed her hands in the machine and saw an image of her hands with her fingers long and lengthened how she felt. Now, if you're like me, I imagine it would feel weird to see my hands distorted. Not grandma though... she was totally delighted. She moved her hands around and watched the image of her long fingers and long hand move. As she did this, she had an amazing experience: her hands no longer hurt! She had no arthritis pain!
Interestingly, I've been seeing more and more research looking at the role of central sensitization as a factor in the pain experience in individuals who have knee osteoarthritis. The study below is noting that as clinician awareness of central sensitization grows, clinicians are trying to incorporate what has been learned in laboratory studies. From this the investigators compiled clinical indicators of central sensitization. Although a list was created, additional research is needed to determine psychometric properties.
Below you will find a quick view of the abstract.
Clinical descriptors for the recognition of central sensitization pain in patients with knee osteoarthritis.
Despite growing awareness of the contribution of central pain mechanisms to knee osteoarthritis pain in a subgroup of patients, routine evaluation of central sensitization is yet to be incorporated into clinical practice.
The objective of this perspective is to design a set of clinical descriptors for the recognition of central sensitization in patients with knee osteoarthritis that can be implemented in clinical practice.
A narrative review of original research papers was conducted by nine clinicians and researchers from seven different countries to reach agreement on clinically relevant descriptors.
It is proposed that identification of a dominance of central sensitization pain is based on descriptors derived from the subjective assessment and the physical examination. In the former, clinicians are recommended to inquire about intensity and duration of pain and its association with structural joint changes, pain distribution, behavior of knee pain, presence of neuropathic-like or centrally mediated symptoms and responsiveness to previous treatment. The latter includes assessment of response to clinical test, mechanical hyperalgesia and allodynia, thermal hyperalgesia, hypoesthesia and reduced vibration sense.
This article describes a set of clinically relevant descriptors that might indicate the presence of central sensitization in patients with knee osteoarthritis in clinical practice. Although based on research data, the descriptors proposed in this review require experimental testing in future studies. Implications forRehabilitation:Laboratory evaluation of central sensitization for people with knee osteoarthritis is yet to be incorporated into clinical practice. A set of clinical indicators for the recognition of central sensitization in patients with knee osteoarthritis is proposed. Although based on research data, the clinical indicators proposed require further experimental testing of psychometric properties.
Disabil Rehabil.2017 Aug 2:1-10. doi: 10.1080/09638288.2017.1358770. [Epub ahead of print]