ABSTRACT
Objective At present, the mainstream surgical mode and the gold standard for the treatment of spine related diseases are still the intervertebral fusion with the intervertebral implantation of the intervertebral fusion device.The intervertebral fusion device routinely used in clinical practice cannot degrade in vivo after implantation, resulting in lifelong foreign body.High elastic modulus also leads to osteoporosis in adjacent vertebral bodies, which leads to implant sinking, stress shielding and'pseudomorphism'of fusion.The ideal biodegradable synthetic intervertebral fusion cage can be progressively degraded and eventually replaced by new bone, which has the advantages of elastic modulus close to cortical bone, good biocompatibility, X-ray permeability and good initial mechanical strength.In this paper, animal analysis of biodegradable intervertebral fusion cage, clinical effect analysis, current shortcomings and future trends were reviewed.
ABSTRACT
<p><b>Objective</b>Combining artificial scaffolds with stimulatory factors to reconstruct lost bone tissues is one of the hottest research directions. The purpose of this review was to conduct a retrospective survey on the latest reports on artificial bone fabrication with functional cytokines.</p><p><b>Data Sources</b>The status of related scientific research from the year 2005 to 2018 was analyzed through the mode of literature retrieval in PubMed and VIP Database. The retrieval words are as follows: "bone tissue engineering," "angiogenesis," "cytokines," "osteogenesis," "biomimetic bone marrow," "sol-gel," "delivery system," and the corresponding Chinese words.</p><p><b>Study Selection</b>After reading through the title and abstract for early screening, the full text of relevant studies was evaluated and those not related with this review had been ruled out.</p><p><b>Results</b>According to the literature retrospective survey, there were three key points for the successful construction of functional artificial bones: (1) the continuous supply of relatively low concentration of cytokines during the required period; (2) the delivery of two or more cytokines essential to the process and ensure the relatively spatial independence to reduce the unnecessary interference; and (3) supporting the early-stage angiogenesis and late-stage osteogenesis, respectively, regulating and balancing the crosslinking of both to avoid the surface ossification that would probably block the osteogenesis inside.</p><p><b>Conclusions</b>The synergistic effect of both angiogenic factors and osteogenic factors applied in bone regeneration is a key point in the combined functional artificial bone. Through analysis, comparison, and summary of the current strategies, we proposed that the most promising one is to mimic the natural bone marrow function to facilitate the regeneration process and ensure the efficient repair of large weight-bearing bone defect.</p>