AB0095 Efficacy of Celecoxib for the Formation of Joint Contracture Followed by Immobilization in a Rat

BackgroundConcomitant with joint contracture, the inflammatory reactions have been shown in immobilized joint. Several investigators reported the effect of anti-inflammatory drugs on joint contracture formation followed by immobilization, however, the exact effect remains uncertain.ObjectivesWe aimed to investigate a favorable effect of selective cyclooxygenase (COX)-2 inhibitor celecoxib (CBX) treatment on immobilization-induced contracture in a rat model.MethodsThirteen-week-old male Wistar rats (n=30) were used in this study. Rats were divided into three groups; control, immobilization (Im), and Im+CBX groups (n=10 each). In IM and Im + CBX groups, the right knee was immobilized by external fixation at 140° of flexion for 3 weeks. In Im+CBX group, CBX (50 mg/kg orally once a day) were treated during immobilization periods. Age-matched untreated animals were used as control group. At the end of intervention period, knee joint passive range of motion (ROM) were measured with14.6 Nmm extension moments before and after transection of knee flexor muscles (the former mainly indicates myogenic-, and the latter indicates arthrogenic contracture). In addition, the knee flexor semitendinosus muscles and knee joints were histologically analyzed to investigate the involvement of morphological alterations on joint contracture formation. For all data, one-way analysis of variance were used for statistically analysis, and the Tukey's post-hoc test were applied. P-value of