Platelet rich plasma complex helps tendon-bone healing after reconstruction of the anterior cruciate ligament in rabbits

Abstract

ObjectiveTo observe the effect of platelet-rich plasma (PRP) combined with deproteinized bone (DPB) of calf as the bone tunnel filling on tendon-bone healing after anterior cruciate ligament (ACL) reconstruction in rabbits.MethodsThirty-six healthy, skeletally mature New Zealand white rabbits were used to create models of totally ruptured ACL at the right knee and then the right ruptured ACLs were reconstructed with semitendinosus tendon autografts. After ACL reconstruction, the 36 rabbits were randomly divided into 3 equal groups for different bone tunnel fillings. PRP + DPB, PRP and nothing but tendon were used to fill the bone tunnels respectively in PRP + DPB, PRP and control groups. Specimens were harvested at 6, 12, 18 weeks after operation for general observation and histological investigation using hematoxylin-eosin staining (HE) and immunohistochemistry staining.ResultsGross observation revealed that the grafted tendon and fibrous tissue at the bone tunnel wall in the PRP + DPB group were superior to those in the other 2 groups at all time points. HE staining showed that tendon-bone healing and grading of fibrous tissue at tendon-bone interface in the PRP + DPB group were better than in the other 2 groups at all time points. The expressions of transforming growth factor-β1 (TGF-β1) were 119. 5 ± 9. 3, 93.0 ± 7. 3, 73.3 ± 5.4 respectively for the PRP + DPB, PRP and control groups at 6 weeks, and 76. 8 ± 5.7, 48. 0 ± 6. 7,26. 8 ±4. 7 for the PRP + DPB, PRP and control groups at 12 weeks. The expressions of vascular endothelial growth factor (VEGF) were 117.5 ± 8.4, 90. 5 ± 8.2, 69. 8 ± 5.8 respectively for the PRP + DPB, PRP and control groups at 6 weeks, and 76. 6 t 5.7, 48.0 ± 6. 7, 26. 8 ± 4. 7 for the PRP + DPB, PRP and control groups at 12 weeks. The above significantly different indexes between the 3 groups showed that the PRP +DPB group was significantly better than the other 2 groups ( P ＜ 0. 05) . But there were no significant differences between the 3 groups in the expressions of TGF-β1 and VEGF at 18 weeks ( P ＞ 0. 05) .ConclusionPRP + DPB can enhance bone-tendon healing after ACL reconstruction in rabbits. Key words: Anterior cruciate ligament; Platelet-rich plasma; Muscle, skeletal