Pain sensitivity, physical activity and the language of pain among aging non-Hispanic White women with knee osteoarthritis

Background: Pain is a debilitating and disabling condition for aging women with knee osteoarthritis (OA). The language of pain has been shown to be a valid and reliable measure of the subjective experience of pain among individuals with similar pain syndromes. This pilot study investigated pressure pain sensitivity and pain descriptors among aging non-Hispanic White (nHW) women with knee OA. Methods: Study included 20 nHW women between the ages of 55-70. Baseline mechanical (algometer) pressure and post-cycling pressure was applied at the medial joint of the most affected arthritic knee. Researchers assessed threshold ratings (first feeling) of pain. Participants also completed the McGill Pain Questionnaire. Results: Mean baseline mechanical pressure pain scores before cycling and mean post-cycling mechanical pressure pain scores were low and not significantly different for ratings of pain sensitivity; 2.23 (1.48) compared to 2.09 (1.46) respectively. However, verbal descriptors of pain sensitivity varied. Women described chronic knee pain as moderately aching (60%); moderately tender (45%), moderately tiring/exhaustive (30%), moderately throbbing and moderately sharp (25%). Mild pain was described as throbbing, hot/burning, tiring/exhaustive and tender (35%). Conclusion: Research shows that the pain experiences of women are unique, and under-treated. Experimental laboratory measures serve as a proxy for assessing chronic, clinical pain. However, assessing the language of pain intensity is important as an additional measure of pain sensitivity especially for aging women; a group who is under-studied in pain research, and a group for whom effective pain treatment to improve health-related quality of life is a public health imperative.