A Secondary Analysis: Comparison of Experimental Pain and Psychological Impact in Individuals with Carpometacarpal and Knee Osteoarthritis

Abstract

Purpose

Evaluate sensory and psychological differences in individuals with thumb carpometacarpal (CMC) and/or knee osteoarthritis (OA) pain. This secondary analysis focuses on comparing the effects of OA at large and small joints in community-dwelling adults.

Patients and Methods

A total of 434 individuals were recruited from communities in Gainesville, FL and Birmingham, AL. Each participant completed health and clinical history questionnaires, quantitative sensory testing, and physical functional tests. Participants were divided into four groups based on their pain (“CMC pain” (n = 33), “knee pain” (n = 71), “CMC + knee pain” (n = 81), and “pain-free” controls (n = 60)). ANCOVAs were performed to identify significant differences in experimental pain and psychological variables across groups.

Results

The “CMC + knee pain” group had lower pressure pain thresholds (lateral knee site, p < 0.01) and higher temporal summation of mechanical pain (knee, p < 0.01) when compared to “CMC pain” and “pain-free” groups. The “knee pain” group had lower heat pain tolerance at the forearm site (p = 0.02) and higher mechanical pain (p < 0.01) at both tested sites in comparison to the “CMC pain” group. Lastly, the “CMC + knee pain” group had the highest self-reported pain (p < 0.01) and disability (p < 0.01) compared to all other groups.

Conclusion

Results suggest knee OA compounded with CMC OA increases disease impact and decreases emotional health compared to OA at either the CMC or knee joint alone. Results also support a relationship between the number of painful joints and enhanced widespread pain sensitivity. Measuring pain at sites other than the primary OA location is important and could contribute to more holistic treatment and prevention of OA progression.

Keywords:

• thumb
• trapeziometacarpal
• multi-site OA
• generalized OA
• quantitative sensory testing

Abbreviations

CMC, carpometacarpal; OA, osteoarthritis; QST, quantitative sensory testing; TS, temporal summation; WOMAC, western Ontario and McMaster universities osteoarthritis index; GCPS, graded chronic pain scale; CSQ-R, coping strategies questionnaire-revised; LOT-R, life orientation test-revised; PANAS, positive and negative affect schedule; SPPB; short physical performance battery; SD, standard deviation.

Ethics Approval of Research on Humans

The procedures followed were in accordance with the ethical standards of the responsible committee on human experimentation (institutional and national) and with the Helsinki Declaration of 1975, as revised in 2000.

Acknowledgments

Funding from the National Institutes of Health (F31 AG074645, KL2 TR001429, and R37 AG033906) and from the University of Florida Graduate Student Preeminence Award is acknowledged. Funding sources were not involved in the preparation of this manuscript.

Disclosure

The authors report no conflicts of interest in this work.