Background The discordance between the structural damage and the severity of the pain in knee osteoarthritis (OA) suggests the effect of central and peripheral sensitization mechanisms on pain perception. This comes into the question of whether the characteristics of neuropathic pain (NP) exist in OA.
Objectives To investigate the existency of NP features in osteoarthritis patients.
Methods A total of 103 patients with knee pain lasting at least 3 months and diagnosed as knee OA based on the criteria of American College of Rheumatology were included in this study. The patients having any disease that may cause NP and having NP medication were excluded. The patients' knee radiographies were graded according to Kellgren Lawrence criteria. The patients were allocated in two groups; as grade I-II (Group 1) and grade III-IV (Group2). The frequency of NP were evaluated by The Leeds Assessment of Neuropathic Symptoms and Signs (LANSS) Pain Scale and Neuropathic Pain Diagnostic Questionnaire (DN4). Additionally the pain at rest and the activity were measured by Visual Analogue Scale (VAS), functional level was assessed by by Knee Outcome Survey-Activities for Daily Living Scale (KOS-ADSL) and quality of life was evaluated by Nottingham Health Profile (NHP).
Results The mean ages of group 1 and group two were 59.74 and 67.30 respectively. The ratio of the results of LANNS and DN4 in group 1 was 10% and 79.2% in goup 2. There were statistically significant differences in group 2 in LANNS, DN-4, VAS, KOS-ADSL, NHP scores (p<0.001). A positive correlation between NP scores (LANNS, DN-4) and the grades of disease was determined (p<0.0001, r=0,80 ve 0,81 respectively). Also there was a positive correlation between NP (LANNS and DN-4) scores and KOS-ADSL (p<0.001, r=0,84 and 0.83). However LANNS and DN-4 were negatively correlated with NHP (p<0.001, r=-0.88 ve -0.87).
Conclusions The coexistence of NP increases with the progression of osteoarthritis. NP seems to have negative effects on functional level and quality of life. While planning a treatment program for progressive OA, NP should be kept in mind program of.
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Disclosure of Interest None declared