Enhanced tendon to bone healing in rotator cuff tear by PLLA/CPS composite films prepared by a simple melt-pressing method: An in vitro and in vivo study

摘要

High failure rate of tendon to bone healing after surgery has always been a challenging problem in rotator cuff repair. Considering the flexibility of PLLA and osteogenic activity of calcium phosphate silicate (CPS) ceramic, PLLA/CPS composite films were produced by a simple melt-pressing technique, the in vitro and in vivo biocompatibility and bioactivity were investigated. With an increase of CPS content, the adhesion and proliferation of cells on composite films were improved. The sample with a PLLA/CPS volume ratio of 5/1 (5P/C) showed a highest ALP activity expression. The in vivo results also revealed that the 5P/C composite sample had good biocompatibility and biodegradability, which could improve the organization of collagen and the formation of cartilage and bone. Moreover, the biomechanical test demonstrated that 5P/C group displayed the best mechanical performance among the three groups. 12 weeks after surgery, a well engineered tendon to bone interface was formed in the PLLA/CPS composite film case.