Project Details
Projekt
Treatment of degenerative cartilage lesions using subchondrally implanted osteoproliferative Mg-Beads Akronym: OAMag-therapy
Subject Area
Orthopaedics, Traumatology, Reconstructive Surgery
Term
from 2018 to 2023
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 404534760
In orthopedics, osteoarthritis is still a big challenge. Up to now, no optimal therapy exists to stop or even cure chondral degeneration. While the pathogenesis is still unclear there is consensus on the etiological involvement of both articular cartilage and subchondral bone. Compared to the original bone substance the sclerotic bone is mechanically less solid which in turn influences negatively the chondral quality. A therapeutic approach to improve the mechanical properties is microfracturing or spudding of the subchondral bone plate. However, this technique is promising only for smaller cartilage lesions. Here, the proposed study aims to step in by additionally implanting cylindrical magnesium based beads into the subchondral bone. The osteoproliferative effect of magnesium has been shown repeatedly during the development of magnesium-based osteosynthesis implants. The Mg-Beads shall influence positively the bone structure and the time needed to improve.For the planned examinations in vitro and in vivo methods are applied. To meet the high requirements concerning microstructure and uniform degradation, firstly, material specific parameters for the production of the Mg-beads will be developed and adapted for magnesium and possible alloys. Secondly, different cell lines are used to examine potential influences on different developmental stages, which are conceivable due to the beads´ location adjacent to the bone marrow. Here, the examinations include molecular biological methods for the determination of collagen type 2, aggrecan or SOX9 and functional methods for the evaluation of e.g. glycosaminoglycans. The subsequent in vivo experiments use an osteoarthritis model in the rabbit to examine the effect of the Mg-beads in all relevant sections. After implantation of the beads into the femur and tibia, blood samples, µ-computed tomographies, protein expression analyses and histological techniques were carried out. Quantity and quality of the bone changes are assessed specifically via bone density, bone volume and trabecular thickness using µCT. Blood and tissue samples (bone and cartilage) were used to determine markers PIPC and TRAcP (anabolic and katabolic bone metabolism), CTX-II and COMP (anabolic and katabolic cartilage metabolism) as well as NGF (nerve growth factor) to assess local and systemic processes. Evaluation of bone – and especially cartilage – quality on a cellular base by histological techniques complete the examinations.
DFG Programme
Research Grants
