Investigation of effects of levobupivacaine injection to rabbit knee joint on histopathologic changes of joint cartilage tissue and changes of serum biochemical parameters.

The aim of this study is to evaluate the effects of intra-articular levobupivacaine on rabbit knee articular cartilage and certain biochemical parameters in the blood. A total of 24 New Zealand rabbits were included to study. Blood sampling was carried out in all animals on the first day, then the subjects were randomly allocated either to the control group (Group C, n = 9) or to the levobupivacaine group (Group L, n = 15). Group C underwent each two intra-articular injections of saline, 0.25 mL into the right knee and 0.50 mL into the left one. Group L was injected 0.25 mL (1.25 mg) of levobupivacaine into the right knee and 0.50 mL (2.5 mg) into the left one. The groups were divided randomly into three. Tissue and blood samples for histologic and biochemical examination were collected from Groups C1 and L1 on the first, C2 and L2 on the second, and C3 and L3 on the tenth day of the study. Interleukin-1β (IL-1 β), interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), and C-reactive protein (CRP) levels were analyzed. No statistically significant differences could be detected when comparing either left or right joints within the same groups and with Group C and L (P > 0.05). Significant elevations of biochemical parameters were found in Group C. It is concluded that levobupivacaine does not lead to significant histologic changes in rabbit articular cartilage. Significant elevations of biochemical parameters being generally found in the C Group, it is thought that such elevations are not linked to levobupivacaine. Intra-articular levobupivacaine may be a safe alternative for use in post-operative analgesia.