Abstract
Muscle is vascular tissue and has a propensity to form bone when exposed to an osteogenic stimulus such as bone cement, bone morphogenetic protein (BMP) and mesenchymal stromal cells (MSCs). The present study evaluated the ability of the autologous muscle free graft to regenerate cranial
bone defects. A critical size defect (8 mm in diameter) was created in the calvarium of 40 rats. Treated autologous muscle grafts were then implanted into the cranial defect. The cases were randomly divided into the following groups: (1) muscle injected with injectable Calcium sulphate/hydroxyapatite
cement (CS/HAC) BMP-7/MSCs (2) muscle injected with CS/HAC/BMP-7, (3) muscle injected with CS/HAC, (4) non-treated muscle. At 8 weeks, the bone regeneration was assessed using microcomputed tomography (micro-CT) and histology. Clinically, cortical bone regeneration was observed bridge the
defects area only in groups (1) and (2). The qualitative assessment of regenerated bone using micro-CT analysis reported thinner trabeculae, compared to normal native bone, with a high degree of anisotropy. Quantitative histomorphometry assessment showed that a high median bone percentage
surface area was reported for group (1) at 64.2±6.0% (36.9-75.3). This study confirms the in vivo osteogenic properties of modified muscle graft and suggests novel strategies for bone regeneration.