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Tendon-bone healing is a complex biological process. Multiple signaling pathways are involved in tendon-bone healing， including transforming growth factor-β signaling pathway， bone morphogenetic protein signaling pathway， Wnt signaling pathway， fibroblast growth factor signaling pathway and nuclear transcription factor-κB signaling pathway. This paper summarizes the research status of traditional Chinese medicine regulating related signaling pathways to promote tendon-bone healing. It is found that a variety of traditional Chinese medicine monomers or herbal extracts （such as baicalein， icariin， total flavonoids of Drynaria fortunei， parthenolide， total saponins of Panax notoginseng， etc.） and traditional Chinese medicine compounds （such as Taohong siwu decoction， Liuwei dihuang pill， Xujin jiegu liquid， etc.） can promote bone formation， anti-inflammatory， anti-oxidation， by regulating the above signaling pathways， thereby effectively promoting tendon-bone healing.
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OBJECTIVE@#To review the bioactive strategies that enhance tendon graft healing after anterior cruciate ligament reconstruction (ACLR), and to provide insights for improving the therapeutic outcomes of ACLR.@*METHODS@#The domestic and foreign literature related to the bioactive strategies for promoting the healing of tendon grafts after ACLR was extensively reviewed and summarized.@*RESULTS@#At present, there are several kinds of bioactive materials related to tendon graft healing after ACLR: growth factors, cells, biodegradable implants/tissue derivatives. By constructing a complex interface simulating the matrix, environment, and regulatory factors required for the growth of native anterior cruciate ligament (ACL), the growth of transplanted tendons is regulated at different levels, thus promoting the healing of tendon grafts. Although the effectiveness of ACLR has been significantly improved in most studies, most of them are still limited to the early stage of animal experiments, and there is still a long way to go from the real clinical promotion. In addition, limited by the current preparation technology, the bionics of the interface still stays at the micron and millimeter level, and tends to be morphological bionics, and the research on the signal mechanism pathway is still insufficient.@*CONCLUSION@#With the further study of ACL anatomy, development, and the improvement of preparation technology, the research of bioactive strategies to promote the healing of tendon grafts after ACLR is expected to be further promoted.
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Animals , Anterior Cruciate Ligament/surgery , Anterior Cruciate Ligament Injuries/surgery , Anterior Cruciate Ligament Reconstruction , Tendons/surgeryABSTRACT
OBJECTIVE@#To investigate the effect of Kartogenin (KGN) combined with adipose-derived stem cells (ADSCs) on tendon-bone healing after anterior cruciate ligament (ACL) reconstruction in rabbits.@*METHODS@#After the primary ADSCs were cultured by passaging, the 3rd generation cells were cultured with 10 μmol/L KGN solution for 72 hours. The supernatant of KGN-ADSCs was harvested and mixed with fibrin glue at a ratio of 1∶1; the 3rd generation ADSCs were mixed with fibrin glue as a control. Eighty adult New Zealand white rabbits were taken and randomly divided into 4 groups: saline group (group A), ADSCs group (group B), KGN-ADSCs group (group C), and sham-operated group (group D). After the ACL reconstruction model was prepared in groups A-C, the saline, the mixture of ADSCs and fibrin glue, and the mixture of supernatant of KGN-ADSCs and fibrin glue were injected into the tendon-bone interface and tendon gap, respectively. ACL was only exposed without other treatment in group D. The general conditions of the animals were observed after operation. At 6 and 12 weeks, the tendon-bone interface tissues and ACL specimens were taken and the tendon-bone healing was observed by HE staining, c-Jun N-terminal kinase (JNK) immunohistochemical staining, and TUNEL apoptosis assay. The fibroblasts were counted, and the positive expression rate of JNK protein and apoptosis index (AI) were measured. At the same time point, the tensile strength test was performed to measure the maximum load and the maximum tensile distance to observe the biomechanical properties.@*RESULTS@#Twenty-eight rabbits were excluded from the study due to incision infection or death, and finally 12, 12, 12, and 16 rabbits in groups A-D were included in the study, respectively. After operation, the tendon-bone interface of groups A and B healed poorly, while group C healed well. At 6 and 12 weeks, the number of fibroblasts and positive expression rate of JNK protein in group C were significantly higher than those of groups A, B, and D (P<0.05). Compared with 6 weeks, the number of fibroblasts gradually decreased and the positive expression rate of JNK protein and AI decreased in group C at 12 weeks after operation, with significant differences (P<0.05). Biomechanical tests showed that the maximum loads at 6 and 12 weeks after operation in group C were higher than in groups A and B, but lower than those in group D, while the maximum tensile distance results were opposite, but the differences between groups were significant (P<0.05).@*CONCLUSION@#After ACL reconstruction, local injection of a mixture of KGN-ADSCs and fibrin glue can promote the tendon-bone healing and enhance the mechanical strength and tensile resistance of the tendon-bone interface.
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Animals , Rabbits , Adipocytes , Anterior Cruciate Ligament Reconstruction , Fibrin Tissue Adhesive/therapeutic use , Stem CellsABSTRACT
BACKGROUND: Whether remnant preservation can improve tendon-bone healing remains a controversy. Experiments were designed to evaluate whether remnant preservation has the biological advantage of promoting tendon-bone healing by histology and imaging. OBJECTIVE: To investigate the effect of preservation of ligament stump on tendon-bone healing in anterior cruciate ligament reconstruction. METHODS: Forty New Zealand rabbits were randomly divided into two groups: anterior cruciate ligament reconstruction group without remnant preservation (group A) and anterior cruciate ligament reconstruction group with remnant preservation (group B), with 20 rabbits in each group. Achilles tendon was selected as the graft, and the bilateral anterior cruciate ligaments of all the rabbits were cut off. In group A, the anterior cruciate ligament stump was completely removed. In group B, the tibia stump was cut off from the femoral stop, and the tibia stump was retained. According to the position of the anterior cruciate ligament of the normal rabbits, the tibia and the femoral canal were selected for reconstruction. At 6 and 12 weeks after surgery, the expression of vascular endothelial growth factor and hypoxia inducible factor-1α was detected by immunohistochemistry. Graft microvessel density was detected by CD34 immunohistochemical staining. The signal intensity of tendon and the width of bone tunnel were observed by MRI and CT. RESULTS AND CONCLUSION: (1) The percentage of hypoxia inducible factor-1α and vascular endothelial growth factor positive cells in group B was significantly higher than that in group A at 6 weeks after operation (P 0.05). (2) At 6 weeks after operation, the expansion of bone tunnel in group B was significantly lower than that in group A, and the signal intensity of tendon graft was lower in group B than that in group A (P 0.05). (3) In this experiment, in the early stage of ligament reconstruction, the anterior cruciate ligament reconstruction with remnant preservation is superior to the anterior cruciate ligament reconstruction without remnant preservation in terms of graft revascularization and reduction of bone tunnel expansion, showing some biological advantages.
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BACKGROUND: Human amniotic mesenchymal stem cells have a wide variety of sources, low immunogenicity, and multilineage differentiation potential. Studies have confirmed that Scleraxis gene can induce human amniotic mesenchymal stem cells to differentiate into ligaments and accelerate tendon-bone healing. OBJECTIVE: To explore whether Scleraxis induces human amniotic mesenchymal stem cells to promote tendon-bone healing in vivo in rabbits, providing new options for clinical treatment of tendon-bone healing. METHODS: The study protocol was approved by the Ethic Committee of the Affiliated Hospital of Zunyi Medical University, and written informed consent was obtained from each puerpera. The healthy full-term maternal placenta was taken and cultured, and human amniotic mesenchymal stem cells were isolated and cultured by trypsin digestion twice. Then the morphology of the cells was observed under an inverted microscope, and the cells were further cultured until the third generation for subsequent experiments. The lentivirus carrying the Scleraxis gene was transfected into human amniotic mesenchymal stem cells in vitro. Expression levels of ligament-related genes were detected by real-time fluorescent quantitative PCR, and the expression levels of related proteins were detected by immunofluorescence. Human amniotic mesenchymal stem cells transfected with Scleraxis gene were injected into the extraarticular tendon-bone model of rats. After 3 months, specimens were taken to observe the tendon-bone healing. RESULTS AND CONCLUSION: (1) Human amniotic mesenchymal stem cells from passage to third generation showed long fusiform and vortex-like adherent growth under the inverted phase contrast microscope. (2) The third-generation human amniotic mesenchymal stem cells expressed green fluorescence after 24 hours of infection with the Scleraxis gene lentivirus, and the fluorescence expression was strong and stable. (3) Cell counting kit-8 findings indicated that lentivirus transfection of Scleraxis gene showed no influence on the cell growth rate. (4) Real-time fluorescent quantitative PCR findings showed that the mRNA expression of Scleraxis and ligament-related genes type I collagen, type III collagen, Fibronectin and Tenascin-C was significantly increased after lentivirus transfection of Scleraxis gene. (5) The results of immunofluorescence showed that the expression levels of ligament-related proteins type I collagen, type III collagen, Fibronectin and Tenascin-C were increased after lentivirus transfection of Scleraxis gene. To conclude, in vivo animal experiments have confirmed that the lentivirus transfection of Scleraxis gene can accelerate the tendon-bone healing of the rabbit extraarticular tendon-bone model.
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BACKGROUND: Acellular amniotic membrane scaffold is a natural scaffold with good biocompatibility, which has been widely used in tissue engineering. Scleraxis can promote the differentiation of human amniotic mesenchymal stem cells into human ligament cells and promote tendon-bone healing. OBJECTIVE: To explore whether acellular amniotic membrane scaffold combined with human amniotic mesenchymal stem cells transfected with Scleraxis can promote rabbit tendon-bone healing. METHODS: (1) Human amniotic mesenchymal stem cells were isolated and cultured in vitro. After passaged, the cell morphology was observed. (2) The Scleraxis lentivirus was constructed in vitro and then transfected into passage 3 human amniotic mesenchymal stem cells with optimal multiplicity of infection. The transfection efficiency was detected by q-PCR. (3) The acellular amniotic membrane scaffold was prepared by enzymatic digestion. Then the Scleraxis lentivirus-transfected cells were seeded on the acellular amniotic membrane scaffold in vitro. The cell growth on the scaffold was observed by phalloidin staining. (4) The New Zealand white rabbit tendon was covered with the acellular amniotic membrane scaffold combined with human amniotic mesenchymal stem cells transfected with Scleraxis lentivirus, followed by implanted into the bone tunnel. The tendon-bone healing was detected. RESULTS AND CONCLUSION: The passage 3 human amniotic mesenchymal stem cells adhered well. (2) After transfected with Scleraxis lentivirus for 96 hours, stable green fluorescence was observed. The mRNA expression level of Sclerxis was significantly increased, indicating a success transfection. The epithelial cells of the acellular amniotic membrane scaffold disappeared, indicating a relatively complete decellularization. The basal layer remained intact, and the extracellular matrix component still existed. Phalloidin staining results revealed that the cells on the acellular amniotic membrane scaffold were in good adhesion and growth, and the cell proliferation was not affected. Therefore, In vivo experimental results reveal that human acellular amniotic scaffold combined with human amniotic mesenchymal stem cells transfected with Scleraxis lentivirus can promote the tendon-bone healing.
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Objective To study the effect of autologous periosteum on the healing of tendon-bone interface in rabbit rotator cuff tear. Methods Supraspinatus tenotomy was performed on one side shoulder in 60 New Zealand white rabbits to establish the model of rotator cuff tear. The rabbits were randomly divided into two groups:the study group(used autologous periosteum to promote the suture fixation)and control group(simple suture fixation). The rabbits were sacrificed at 4,8 and 12 weeks postoperatively with twenty rabbits sacrificed each time. Tissue samples of the tendon-bone interface was taken for histological examination and biomechanical test was performed to assess the strength of tendon-bone junction. Results At 4 weeks the study group showed extensive inflammatory cell infiltration, and a small amount of chondrocytes and extracellular matrix. At 8 weeks, the study group showed a large amount of immature chondrocytes arranged rather regularly. At 12 weeks,the tendon bone junction appeared similar to normal. In the study group,both the tendon-bone connection and the arrangement of chondrocytes were significantly better than the control group. The result of biomechanical testing showed that the highest tendon load in the study group was significantly higher than the control group (P < 0.05). Conclusions The use of autologous periosteum as a patch to strengthen the repair of the rotator cuff tear can effectively promote the healing of tendon bone interface, shorten the rotator cuff healing time and has good biological properties. This method provides an experimental basis for clinical rotator cuff repair surgery.
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Objective: To explore the effect of silk fibroin/poly( L-lactic acid-co-e-caprolactone) [SF/P(LLA-CL)] nanofibrous scaffold on tendon-bone healing of rabbits.
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Objective To evaluate the early effect of leukocyte-and platelet-rich fibrin (L-PRF)on tendon-bone healing in rabbits' extra-articular bone tunnel.Methods Thirty healthy New Zealand rabbits were randomly divided into an experimental group and a control group,each of 15.The semitendinosus tendon harvested from the hind leg of each rabbit was prepared as free autografts.Each autograft was implanted into the bone tunnel created at ipsilateral proximal tibial metaphysis.The experimental group was added with autologous peripheral blood-derived L-PRF,while the control group did not add anything.Speciments from each group were harvested at 4,8 and 12 weeks after operation.The morphological changes were observed and evaluated at each time point.The fibroblasts on the tendon-bone interface were counted and analyzed under the high magnification microscope.Results The number of fibroblasts between the tendon and bone in the experimental group was significantly higher than that of the control group at each time point (P＜0.05).And the connection between tendon and bone was closer and the collagen fibers were more regular in the experimental group than the control group at each time point.Sharpey's-like fibers which marked the early healing of the tendon to bone,were observed at 4th week in the experimental group,while they were observed at 8th week in the control group.As the healing time extended,Sharpey's like fibers continue to increase in both groups and significant differences were observed in the histological morphology (Buark grades)between the two groups (P＜0.05).Conclusion Autologous peripheral blood-derived L-PRF can promote early healing of autologous tendon to bone in the extra-articular bone tunnel of model rabbit.
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Objective To evaluate the effect of transforming growth factor β1 (TGF-β1) on early tendon-bone healing after reconstruction of rotator cuff tears in Wistar rats. Methods The models of rotator cuff supraspinatus tendon by full-thickness transverse tears at the greater tuberosity point in bilateral upper limbs of 54 Wistar rats were established and reconstructed. TGF-β1 induced by fibrin glue was injected at the tendon-bone interface to release osteogenesis after 6 weeks. The rats were randomly divided into low-dose TGF-β1 group, high-dose TGF-β1 group and control group, and then executed randomly at 1st, 2nd and 3rd week to make the supraspinatus specimens for biomechanical testing. Results The rupture point was formed within the suture of rotator cuff in each group by visual observation. The maximum tensile strength, maximum loading percentage, stiffness and maximum cross-section area of tendon-bone interface in high-dose group were higher than those in low-dose group and control group (P<0.05). The maximum loading percentage，maximum tensile strength, stiffness, stiffness percentage and the maximum cross-section area of tendon-bone interface in low-dose group were significantly higher than those in control group (P<0.05). High-dose TGF-β1 could promote the healing during early reconstruction of rotator cuff tears, the tensile strength and stiffness at the tendon-bone interface would increase with the rehabilitation period prolonging. Conclusions TGF-β1 can increase the maximum tensile strength, maximum loading percentage, stiffness and maximum cross-section area of tendon-bone interface, induce the fractured section to directly generate complex structure, thus promote the healing of rotator cuff tears.
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Objective To investigate the effect of transforming growth factor β1 (TGF-β1) on the early reconstruction of Wistar rats rotator cuff tears through the tendon-bone healing biomechanical testing . Methods A total of 45 healthy Wistar rats were randomly divided into three groups: the high-dose, the low-dose, and the control group, with 15 animals in each group. The rats underwent full thickness leisure and reconstructive surgery by suture-bridge and TGF-β1 injection at the tendon bone interface. The parameters of tendon-bone interface biomechanics, including tensile strength, cross-section area, stiffness, percentage of loading, were measured at 1-, 2-, 3-weeks post surgery. Results No significant differences werey observed at the fracture point within the tendon suture among the three groups The maximum tensile strength , maximum load percentage, stiffness and tendon bone repair interface in the high-dose group were higher than those in the low-dose group and those in the control group(P < 0.05, respectively). The maximum axial loading, tensile strength and stiffness of the tendon-bone interface in the low-dose group were significantly higher than those in the control group (P < 0.05). The high-dose group renovated the tendon-bone interface healing and increase stiffness with the extension of the rehabilitation. Conclusion TGF-β1 can enhance the maximum tensile strength of the tendon-bone and promote the healing of rotator cuff injury.
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Objective To observe the effect of bone marrow-derived mesenchymal stem cells (bMSCs) on graft healing within a bone tunnel after anterior cruciate ligament (ACL) reconstruction in rabbits.Methods The study involved 24 New Zealand white rabbits undergone ACL reconstruction with an autologous ipsilateral gastrocnemius tendon graft.Both hindlimbs were included.In one hindlimb,graft coated with fibrin glue compound by bMSCs was employed (bMSCs group).Whereas in the contralateral hindlimb,graft coated with fibrin glue without cells was employed (control group).At postoperative 2,4,6 and 8 weeks,specimens were harvested to have a biomechanical test of tensile strength and stiffness of tendon-bone interface.Results Tensile strength and stiffness of tendon-bone interface in both experiment and control groups presented a rising trend with the prolong of repair time.In contrast,significantly higher tensile strength and stiffness of tendon-bone interface were observed in experiment group since the 6 weeks (P ＜ 0.05).Conclusion bMSCs transplantation significantly enhances the early tensile strength and stiffness at tendon-bone interface after ACL reconstruction in rabbits and improves the graft healing within a bone tunnel.
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BACKGROUND:Anterior cruciate ligament is the important anatomic structure to maintain the knee joint stability. The tendon bone healing and clinical functional recovery after anterior cruciate ligament have attracted more attention. OBJECTIVE:To observe the healing of graft tendon and surrounding bone with histological method through the same diameter grafts matching with the bone tunnel of different sizes in the anterior cruciate ligament reconstruction surgery, and to detect the functional recovery with biomechanics. METHODS:Middle 1/3 of canine autologous tendon was selected as the anterior cruciate ligament graft, and then trimmed into the same diameter of 4 mm. Sixteen adult mongrel canine were randomly divided into four groups. The anterior cruciate ligament was resected completely, and the tibial and femoral tunnels were prepared on the end sites of tibia and femur with the diameters of 5, 4.5, 4 and 3.5 mm, then implanted into the tendon in prepared and linked into the bone tunnel. At 6 weeks after reconstruction, the experimental canine were sacrificed under general anesthesia to col ect the tissue and organs in the surgical area. Then the hematoxylin-eosin staining, biomechanical testing and statistical analysis were performed. RESULTS AND CONCLUSION:At 6 weeks after anterior cruciate ligament reconstruction, anatomical observation showed that there were no significant differences in growth of grafts and bone tunnels between groups;hematoxylin-eosin staining showed sharpey-like fibronectin could be seen in the tendon bone healing surface, and the col agen fibers in the 3.5 mm bone tunnel group were more compact and regular than those in the other groups;the biomechanical testing results in the 3.5 mm bone tunnel group were better than those in the other groups. The results indicate that during anterior cruciate ligament reconstruction, decreasing the diameter of bone tunnel that matched with grafts in order to make the tendon and the bone tunnel closely matched can provide a more stable cel biological and mechanical environment, accelerate the formation and transformation of tendon-bone healing interface, and can improve the quality of tendon-bone healing.
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Objectlve To explore the effect of platelet-rich plasma (PRP) on cellular proliferation and intracytoplasm calcium ion concentration of osteoblasts and tenocytes during the process of tendon-bone healing. Methods We established a kind of indirect co-culture system using transwell chambers to co-culture osteoblasts and tenocytes.The cellular proliferation was carried out in following manners:single culture of osteoblasts versus single culture of osteoblasts plus PRP and co-culture of osteoblasts versus co-culture of osteoblasts plus PRP; single culture of tenocytes versus single culture of tenocytes plus PRP and co-culture of tenocytes versus co-culture of tenocytes plus PRP.The cellular proliferation rates were measured by CCK-8 test.The intracytoplasm calcium ion concentration of was measured by laser confocal microscopy and fluo-3/AM. Results The proliferation rates and fluorescence intensities in the co-culture groups without PRP were significantly lower than other groups ( P ＜ 0.05).The proliferation rates and fluorescence intensities in the single culture groups without PRP were significantly higher than in the co-culture groups without PRP but significantly lower than in the groups with PRP ( P ＜ 0.05).The proliferation rates and fluorescence intensities in the groups with PRP were significantly higher than other groups ( P ＜ 0.05) but there was no significant difference between groups of the same cells ( P ＞ 0.05).The intracytoplasm calcium ion concentrations were proportional to the proliferation rates. Conclusions During the process of tendon-bone healing,PRP has a potential not only to wipe off the depression effect of osteoblasts and tenocytes co-cultured indirectly but also to enhance the cellular proliferation rate to a higher level.At the same time the calcium ion concentrations will be elevated.
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[Objective]To explore the effects of joint synovial fluid on tendon-bone healing of reconstructed ligament. [Methods]Forty female New Zealand rabbits,aged 6 months,weight 2.5~3.5 kg,were divided into 4 groups randomly.Transfer of semitendinosus tendon to the bone tunnels was performed to make bone-tendon healing model,on the right knee the bone tunnel was not communicated to the joint cavity,in contrast,the bone tunnel on the left knee was connected with synovial fluid.Animals in one group were killed at 8 weeks after operation,bone-tendon healing samples were harvested for biomechanical test.Animals in other three groups were killed at 2,4 and 8 weeks after operation respectively to harvest the samples for histological observation.HE and Masson staining were conducted to examinant histological change.[Results]At 2 weeks after operation,there was no significant difference between non joint synovial fluid group and joint synovial fluid group in bone-tendon interface healing,which were filled with granulation tissue.At 4 weeks postoperatively,interface healing in non joint synovial fluid group was obvious better than that in joint synovial fluid group.Fibroblast cells and cartilage cells increased obviously,and collagen fibers synthesized.At 8 weeks after operation,tendon-bone interface in joint synovial fluid group was filled with connective tissue,the collagen fibers arranged disorderly.In contrast,more compact collagen fibers were seen in non joint synovial fluid group.Interface cell accounts in non joint synovial fluid group were superior to that in joint synovial fluid group at 2,4,8 weeks after operation (P
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[Objective]To explore the effects of extracorporeal shock waves(ESW) therapy on tendon-bone healing after reconstruction of the anterior cruciate ligament(ACL).[Method]Animal model of reconstruction of the anterior cruciate ligament in 18 healthy F/M New Zealand white rabbits(2～3 months old) were established using digital long extensor tendon and randomly classified into 2 groups.The ESW group was given extracorporeal shock waves therapy on 24 hours after reconstruction of the anterior cruciate ligament while the control group with only reconstruction of the anterior cruciate ligament but no more therapy.All animals were sacrificed at 2、4、8 weeks after operation for histological examinations.The specimens were stained with hematoxylin-eosin and Masson trichrome to investigate pathology change of the tendon-bone healing tissue.The ink intravascular injection was used to observe the neo-vascularization of tendon-bone healing tissue.[Result]The histological examination revealed that at 4 weeks after operation,the ESW group,tendon-bone interface was filled with proliferated fibroblasts and chondroblasts,the collagen fibers were obviously increased and regularly arranged.At 8 weeks after operation,the healing tissue at the bone-tendon interface had developed into dense connective tissue,the collagen fibers were formed in abundance and the perpendicular collagen fibers were regularly and longitudinally arranged.The transition zones of collagen fibers,fibrocartilage and bone(the structure alike a direct ligamentous insertion) occurred in the local region of tendon-bone interface.The histological observations showed that the tissue healing at tendon-bone interface of the ESW group were quicker than those of the control group.The proportion of neo-vessels at the tendon-bone interface of the ESW group were significantly higher than those of the control group at 4 and 8 weeks after operation(respectively P=0.028,P=0.008).[Conclusion]Extracorporeal shock wave treatment can significantly improve the tendon-bone early healing after reconstruction of the anterior cruciate ligament in rabbits.
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PURPOSE: This study evaluated the effect of the periosteum-wrapped tendon on tendon-to-bone healing using a rabbit model. MATERIALS AND METHODS: Twenty New Zealand white rabbits were used. The animals were divided into two groups, a group with periosteum-wrapped tendon and a control group without a periosteal wrap. Both legs were operated upon in the same manner. The long digital extensor tendon was harvested and transplanted into the proximal tibial tunnel. One limb was transplanted with the tendon wrapped with periosteum facing the cambium layer to the tendon, while the other was without periosteum. The healed tendon-bone attachment was evaluated at 3-weeks and 6-weeks histologically and by biomechanical testing. RESULTS: At 3 and 6 weeks, histologic examination demonstrated more extensive bone formation around the tendon with closer apposition of new bone to the tendon in the limb with the periosteum-wrapped tendon graft than in the control limb. Biomechanical testing demonstrated the higher pullout strength of tendon in the limb with the periosteum-wrapped tendon graft at 3 and 6 weeks with statistically significant differences between the limb with the periosteum-wrapped tendon graft and the control limb at 3 and 6 weeks. CONCLUSION: Histological and biomechanical data suggest superior healing in the periosteum-wrapped group. This study demonstrates that periosteum can enhance the healing process when a tendon graft is transplanted into a bone tunnel.