Multilevel lumbar fusion usually requires a large quantity of iliac crest bone graft but the supply is usually insufficient, so an alternative bone graft substitute for autograft is needed. This prospective study inve...Multilevel lumbar fusion usually requires a large quantity of iliac crest bone graft but the supply is usually insufficient, so an alternative bone graft substitute for autograft is needed. This prospective study investigated the efficacy of calcium sulfate by comparing the fusion rates between the experimental material (calcium sulfate pellets with bone chips from laminectomy) and autologous iliac bone graft in long segment (three-or four-level) lumbar and lumbosacral posterolateral fusion. Forty-five patients with degenerative scoliosis or spondylolisthesis received multilevel spine fusion and decompression. The experimental material of calcium sulfate pellets with decompression bone chips was placed on the experimental side and the iliac crest bone graft was placed on the control side. The fusion status was assessed radiographically at three-month intervals, and solid fusion was defined as a clear continuous intertransverse bony bridge at all levels. The average follow-up period was 34.4 months. Twenty-nine (64.4%) patients showed solid fusion on the experimental side and 39 (86.7%) patients on the control side. The overall fusion rate was 86.7%. A statistically significant relation was found between the two sides with the Kappa coefficient of agreement of 0.436. Compared to the control side, the fusion rate of experimental side is significantly reduced (p = 0.014). The fusion ability of autograft is higher than the experimental material in multilevel lumbar posterolateral fusion. However, the overall fusion rate of calcium sulfate pellets is improved, compared with previously reported rates, which suggested that such material may be considered as an acceptable bone graft extender.展开更多
Bone marrow(BM),a natural niche rich in growth factors and bone marrow mesenchymal stem cells(BMSCs),provides an optimal regenerative microenvironment and is widely used in clinical applications.However,the limited pr...Bone marrow(BM),a natural niche rich in growth factors and bone marrow mesenchymal stem cells(BMSCs),provides an optimal regenerative microenvironment and is widely used in clinical applications.However,the limited proliferative capacity of BMSCs and the mismatch between bone regeneration and growth factors release constrain their effectiveness in treating critical bone defects.Drawing inspiration from the regenerative properties of BM,we developed self-assembled hybrid microspheres to replicate its function and address these challenges through a tissue engineering approach.This BM-mimicking niche enriched BMSCs via fast-degrading gelatin methacryloyl(GelMA)microspheres,which were loaded with exogenous BMSCs and conjugated with stem cell homing peptides(SKP)to recruit endogenous BMSCs.SKP further enhanced the stemness of BMSCs,thereby promoting angiogenesis and resolving inflammation.Slow-degrading chitosan methacryloyl(ChitoMA)microspheres facilitated sustained release of angiogenic(KLT)and osteogenic(OGP)peptides,supporting blood vessel maturation and osteogenesis.The early release of BMSCs and SKP,followed by the subsequent release of OGP and KLT,aligned with the dynamic process of bone regeneration.In a rat critical femoral condyle defect model,the BM-mimicking niche formed an in-situ ossification center,significantly enhancing bone regeneration.This study introduces a novel BM-mimicking niche characterized by a BMSC-enriched environment and the sequential release of therapeutic factors,offering a promising strategy for treating critical bone defects.展开更多
文摘Multilevel lumbar fusion usually requires a large quantity of iliac crest bone graft but the supply is usually insufficient, so an alternative bone graft substitute for autograft is needed. This prospective study investigated the efficacy of calcium sulfate by comparing the fusion rates between the experimental material (calcium sulfate pellets with bone chips from laminectomy) and autologous iliac bone graft in long segment (three-or four-level) lumbar and lumbosacral posterolateral fusion. Forty-five patients with degenerative scoliosis or spondylolisthesis received multilevel spine fusion and decompression. The experimental material of calcium sulfate pellets with decompression bone chips was placed on the experimental side and the iliac crest bone graft was placed on the control side. The fusion status was assessed radiographically at three-month intervals, and solid fusion was defined as a clear continuous intertransverse bony bridge at all levels. The average follow-up period was 34.4 months. Twenty-nine (64.4%) patients showed solid fusion on the experimental side and 39 (86.7%) patients on the control side. The overall fusion rate was 86.7%. A statistically significant relation was found between the two sides with the Kappa coefficient of agreement of 0.436. Compared to the control side, the fusion rate of experimental side is significantly reduced (p = 0.014). The fusion ability of autograft is higher than the experimental material in multilevel lumbar posterolateral fusion. However, the overall fusion rate of calcium sulfate pellets is improved, compared with previously reported rates, which suggested that such material may be considered as an acceptable bone graft extender.
基金funding support from the Beijing Science and Technology Project(Z241100009324005)National Key Research and Development Program of China(2023YFC2412302).
文摘Bone marrow(BM),a natural niche rich in growth factors and bone marrow mesenchymal stem cells(BMSCs),provides an optimal regenerative microenvironment and is widely used in clinical applications.However,the limited proliferative capacity of BMSCs and the mismatch between bone regeneration and growth factors release constrain their effectiveness in treating critical bone defects.Drawing inspiration from the regenerative properties of BM,we developed self-assembled hybrid microspheres to replicate its function and address these challenges through a tissue engineering approach.This BM-mimicking niche enriched BMSCs via fast-degrading gelatin methacryloyl(GelMA)microspheres,which were loaded with exogenous BMSCs and conjugated with stem cell homing peptides(SKP)to recruit endogenous BMSCs.SKP further enhanced the stemness of BMSCs,thereby promoting angiogenesis and resolving inflammation.Slow-degrading chitosan methacryloyl(ChitoMA)microspheres facilitated sustained release of angiogenic(KLT)and osteogenic(OGP)peptides,supporting blood vessel maturation and osteogenesis.The early release of BMSCs and SKP,followed by the subsequent release of OGP and KLT,aligned with the dynamic process of bone regeneration.In a rat critical femoral condyle defect model,the BM-mimicking niche formed an in-situ ossification center,significantly enhancing bone regeneration.This study introduces a novel BM-mimicking niche characterized by a BMSC-enriched environment and the sequential release of therapeutic factors,offering a promising strategy for treating critical bone defects.
