Differences in pain intensity in anti- and pro-nociceptive pain profile subgroups in patients with knee osteoarthritis.

AIM: Facilitated temporal summation is one component of central sensitization. The aim of this exploratory study was to classify pro-, eu- and antinociceptive subgroups based on wind-up ratio cut-off scores in patients with knee osteoarthritis (OA). PATIENTS & METHODS:  A total of 56 patients with knee OA met the inclusion criteria. Temporal summation was measured and wind-up ratio was calculated. Reference values of 180 healthy subjects were used to define wind-up ratio cut-off scores. RESULTS: Twenty-seven percent of patients showed a pro-nociceptive pain profile. Sixteen percent of patients showed an anti-nociceptive pain profile. A eu-nociceptive pain profile was present in 57% of patients. CONCLUSION: Central pain sensitization was present in approximately a third of knee OA patients. The results should be confirmed in larger studies.