The Evaluation of Intra-Articular Injection of Bevacizumab on the Prevention of Physeal Bar Formation in Type 4 Salter Harris Model in Rats: A Pilot Study

This study was designed to achieve a new method as a preventive treatment for complications of growth plate fractures. In this study, we investigate the effect of intra-articular injection of anti-vascular endothelial growth factor (anti-VEGF) antibody bevacizumab on the repair process of articular cartilage in a type 4 Salter Harris injury model.

A Salter Harris injury was created on the proximal tibial growth plate of 14 rats by a 1.8 mm drill. The rats were randomly classified into two groups: group LD, administration of high-dose intra-articular injection of bevacizumab (250 μg), and group HD, administration of low-dose intra-articular injection of bevacizumab (50 μg) after injury. The rats were killed 2 months postoperatively and their tibia underwent micro-computed tomography (CT) analysis, histological assessment, and measurement of tibial bone length.

Bony bar formation was observed in 71% of the samples in the high-dose group and in 100% of the low-dose group. Relative increase in physeal cartilage thickness (P = 0.007) and decrease in bony bar formation (P = 0.029) were observed significantly in the high dose group. There was no significant difference in tibia length between the two groups (P = 0.150).

Intra-articular administration of bevacizumab demonstrated positive restorative effects. We suggest this method of treatment due to its potential of improving cartilage repair and capability to be used as a main or adjacent treatment in osteochondral defects.