Enhancement of tendon-bone healing of rotator cuff with recombinant human bone morphogenetic protein-2 in rabbits:a histological and biomechanical study / 中国矫形外科杂志

ABSTRACT

[Objective]To evaluate the effectiveness of recombinant human bone morphogenetic protein-2 in the repair of rabbit rotator cuff injury.[Method]Forty-eight male New Zealand rabbits,aged 8 months,received an rotator cuff acute injury and reconstruction of the insertion of supraspinatus tendon on greater tuberosity of humerus.The rabbits were randomly divided into 3 groups postoperatively(1) rhBMP-2 groupfibrin sealant(FS) containing rhBMP-2 was applied to the interface between the bone-tendon interface; (2)FS control grouponly FS was applied;(3)blank control groupuntreated after the surgery.Harvested 36 specimens underwent biomechanical analysis at the 2nd,4th,8th postoperative weeks respectively.Harvested 12 specimens underwent histological analysis at the 8th postoperative week.[Result]Histological examination showed that Sharpey's fibers were found in the interface with the formation of four-layer indirect insertion in the rhBMP-2 group at the 8th postoperative week.In the FS control group and blank group,the tendon-bone interface was filled with granulation tissue and part of Sharpey's fibers and the newly generated bone tissue.Biomechanical analysis displayed that the tensile strength and stiffness of bone-tendon interface increased time-dependently in all groups,and it in the rhBMP-2 group was significantly higher than those in the other two groups at any time-points (both P