RETRACTED: Establishment and evaluation of contracture model of knee joint (Retracted Article)

Objective: to establish an animal model of articular contracture of the knee joint of rabbits and evaluate it so as to provide reliable and stable objective basis for clinical observation of rehabilitation nursing program for patients with disuse syndrome. Methods: Twenty New Zealand white rabbits, weighing between 2.5-3.5kg and fed with normal diet for one week, were used to fix the right knee joint contracture model for 4 weeks. After a week of normal feeding, experimental animals were randomly divided into normal group and control group with 10 animals in each group. At the end of the 4th week after operation the internal fixation was removed: after anesthesia the Kirschner needle was cut off from the posterior side of the femur and pulled out from the tibial end. The ROM was measured under anesthesia. Routine antibacterial, dressing change, wire removal. One week after removal of internal fixation, Doppler ultrasound was used to measure the hemodynamic parameters of left lower extremities in both groups, including peak systolic velocity (PSV), end diastolic velocity (EDV), ROM of joint contracture limb and peripheral shank, Synovium and muscle tissue were extracted and sections were stained with HE for morphological observation after the animals were killed. Results: In the model group, the articular space was clearly narrow, the articular surface was uneven, osteophytes were formed and subchondral bone sclerosis. In the normal group, the articular space was normal, the articular surface was smooth, the edge of the joint was smooth, the bone density under cartilage was even and the local tissue was affected. In the model control group, the ROM of the left knee joint was limited, the peripheral tibia was smaller, and the difference was significant.P < 0.05. There was significant difference between two groups (P < 0.05). Conclusion: articular contracture is a secondary complication of disuse syndrome with high frequency, and this model can cause limited range of joint movement and cross section diameter . This symptom is similar to the common symptoms of joint contracture. (C) 2019 Elsevier B.V. All rights reserved.