Injectable temperature-sensitive hydrogel with VEGF loaded microspheres for vascularization and bone regeneration of femoral head necrosis

•The hydrogels with VEGF loaded microspheres were prepared.•The vascular endothelial cells were encapsulated into the hydrogels.•The vascular endothelial cells had a good proliferation.•The composite hydrogels could be injected into necrosis site of femoral head.•The vessels could be observed in the first 2 weeks.