Background: Injury to the medial collateral ligament (MCL) of the knee joint is the most common ligament injury of the knee. Ligament healing generally takes a long time. Micro-ribonucleic acid (miRNA) is one of the noncoding RNAs and plays a crucial role in physiological function;miRNA (miR)-210 is known as a potent factor of angiogenesis, which is an important initiator of ligament healing. T…