Thickening of the long bone: mechanisms and clinical implications / 中国组织工程研究

ABSTRACT

BACKGROUND:The thickening of living bone is an important natural rule,and genetic,nutritional and endocrine factors play critical roles in the bone thickening;however,these factors are site-blind.OBJECTIVE:To analyze the mechanism underlying the thickening of the long bone.METHODS:Clinical cases and literature were analyzed.Medline and CNKI databases were retrieved using the keywords of "bone growth in width,skeletal thickening,bone thickening,periosteal apposition" in English and Chinese,respectively.Totally 12 eligible articles were included for result analysis.RESULTS AND CONCLUSION:The mechanical environment of the bone plays a key role in the bone remodeling,which is a site-specific process.The thickening of the long bone is completed through the periosteal apposition,and the coupling effect of stress-angiogenesis-osteogenesis induced by overloading is the pathological basis of bone thickening.The periosteal apposition and periosteal resorption belong to a lifelong dynamic process,and the bending stress is the most important factor to maintain the periosteal osteogenesis.If the bone is shielded from bending stress to a certain extent by the metal fixators,it may lead to bone resorption and thinning,nonunion and other serious consequences.Therefore,the strength of the fixators should match the patient body mass and the thickness of the bone.The marrow cavity is a natural low stress region,so intramedullary fixation theoretically has little effect on the width growth of bone.