title: Generation of tendon-to-bone interface "enthesis" with use of recombinant BMP-2 in a rabbit model.
abstract: The anatomical structure at bone-tendon and bone-ligament interfaces is called the enthesis. Histologically, the enthesis is characterized by a transitional series of tissue layers from the end of the tendon to bone, including tendon, fibrocartilage, calcified fibrocartilage, and bone. This arrangement yields stronger direct connection of the soft tissues to bone. In surgical repair, the enthesis has proven difficult to reproduce, and the success of ligament-bone bonding has depended on the fibrous attachment that forms after any ligament reconstructions. In this study, we attempted to generate a direct-insertion enthesis in two stages. First, recombinant human bone morphogenetic protein-2 (rhBMP-2) was injected into the flexor digitorum communis tendon in the rabbit hind limb to induce ectopic ossicle formation. In a second step, the resultant tendon/ossicle complex was then surgically transferred onto the surface of the rabbit tibia to generate a stable tendon-bone junction. One month following surgery, histomorphological examination confirmed direct insertion of tendon-bone structures in the proximal tibia of the rabbit. Ultimate failure loads of the BMP-2-generated tendon-bone junction were significantly higher than in the control group (p < 0.01). These findings suggest that it is possible to successfully regenerate a direct tendon-to-bone enthesis. Use of this approach may enable successful reconstruction of joints rendered unstable after ligamentous rupture or laxity after anterior cruciate ligament injury.
authors.affiliation: Department of Orthopaedic Surgery, Osaka City University Graduate School of Medicine, Osaka, Japan. hussy@med.osaka-cu.ac.jp
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Hashimoto
authors.forename: Gen
authors.initials: G
authors.lastname: Yoshida
authors.forename: Hiromitsu
authors.initials: H
authors.lastname: Toyoda
authors.forename: Kunio
authors.initials: K
authors.lastname: Takaoka
mesh_terms: D000125:Achilles Tendon / Q000000981:diagnostic imaging / Q000187:drug effects* / Q000473:pathology; D000818:Animals; D055396:Bone Morphogenetic Protein 2; D019485:Bone Morphogenetic Proteins / Q000494:pharmacology*; D002113:Calcification, Physiologic / Q000187:drug effects* / Q000502:physiology; D002358:Cartilage, Articular / Q000000981:diagnostic imaging / Q000187:drug effects / Q000473:pathology; D004195:Disease Models, Animal; D005260:Female; D051445:Fibrocartilage / Q000000981:diagnostic imaging / Q000187:drug effects / Q000473:pathology; D010012:Osteogenesis / Q000187:drug effects*; D011817:Rabbits; D011994:Recombinant Proteins / Q000494:pharmacology; D013314:Stress, Mechanical; D013709:Tendon Transfer; D013977:Tibia / Q000000981:diagnostic imaging / Q000187:drug effects / Q000473:pathology; D014057:Tomography, X-Ray Computed; D016212:Transforming Growth Factor beta / Q000494:pharmacology*; D016474:Weight-Bearing; D014945:Wound Healing / Q000187:drug effects*
chemical_list: C525718:BMP2 protein, human; D055396:Bone Morphogenetic Protein 2; D019485:Bone Morphogenetic Proteins; D011994:Recombinant Proteins; D016212:Transforming Growth Factor beta