Comparison of intra-articular injection of parecoxib vs oral administration of celecoxib for the clinical efficacy in the treatment of early knee osteoarthritis

BACKGROUND Non-steroid anti-inflammatory drugs (NSAIDs) have played a crucial role in the treatment of osteoarthritis, especially in the early stages. However, the cardiovascular risk and adverse gastrointestinal reactions of oral NSAIDs in elderly people cannot be underestimated. Intra-articular injection of NSAIDs may be a new attempt for early knee osteoarthritis treatment. Parecoxib may be a suitable drug for intra-articular injection. AIM To observe the clinical efficacy of the intra-articular injection of parecoxib for early knee osteoarthritis. METHODS Early knee osteoarthritis patients (n = 110) were retrospectively analyzed. These patients were divided into three groups: Basic treatment + oral glucosamine (group A, n = 37), oral celecoxib + basic treatment + oral glucosamine (group B, n = 37), and intra-articular injection of parecoxib + basic treatment + oral glucosamine (group C, n = 36). Intra-articular injection of parecoxib was performed once every 2 wk at a dose of 40 mg each time, for three times total. The three groups were compared in terms of visual analogue scale (VAS) scores, Hospital for Special Surgery (HSS) scores and patient satisfaction before and after treatment. The levels of inflammatory cytokines in the synovial fluid were detected in the three groups before and after treatment. RESULTS All patients were followed up for an average of 15.5 +/- 2.7 mo. The clinical efficacy was estimated by VAS and HSS scores at 12 mo after treatment. Inflammatory cytokine levels in the synovial fluid were evaluated at 3 mo after treatment. VAS and HSS scores were significantly improved in each group compared with before (P < 0.001). There were significant differences among the three groups in VAS and HSS scores (P < 0.001). The clinical efficacy of group C was superior to that of groups A and B (P < 0.001), while group B outperformed group A in this respect (P < 0.001). The patient satisfaction was the highest in group C (P < 0.001). After treatment, the levels of tumor necrosis factor alpha (TNF-alpha) and interleukin (IL)-6 in the synovial fluid decreased in each group compared with before (P < 0.001), while the levels of IL-10 increased (P < 0.001). The three groups differed significantly in the levels of TNF-a, IL-6 and IL-10 in the synovial fluid after treatment (P < 0.001). CONCLUSION For patients with early knee osteoarthritis, intra-articular injection of parecoxib could effectively improve clinical symptoms. This method may be a reliable alternative for early knee osteoarthritis.