Bone marrow transplantation treatment is not linked with bone damage, through the clinical trials, it has applied in the human body and obtains good effects, mainly plays the leading role in the marrow by the marrow mesenchymal stem cell, and promote bone fracture healing, but the mesenchymal stem cell's level is extremely low in the marrow, and the massive marrow is needed to be able to obtain enough cell quantity. At present the majority type of bone marrow stem cell's application is still at the animal experimentation stage, the clinical research mainly adopts the bone marrow mononuclear cell transplant. One scholar[26] has purified and increased the marrow mesenchymal stem cell through in vitro culture technique, and obtained the satisfactory progress to repair the rabbit radius distal end bone damage. The purified and increased bone marrow mesenchymal stem cells applied in clinical through in vitro culture technique, for healing the human body bone fracture, remains poorly reported. This group lays the successful foundation for animal experiments, used the short-term concentration separated and purified bone marrow mesenchymal stem cell transplant treatment to heal bone nonunion, increased stem cell's effective quantity, achieve nucleated cell quantity to 4×109/L. In the course of treatment, the bone callus formation was observed at 1 month after transplantation, continual callus formation observed at 3 months after transplantation, and no obvious tenderness appeared at bone fracture site. Comparison of bone healing time between 2 groups: The average healing time of the autologous MSC transplant group was significantly shorter than autogenous iliac bone graft group [(5.5 ± 1.5) months, (8.0 ± 2.0) months, P < 0.05]. The single bone marrow transplant and reduction treatment at 1 month proved that through the simple effective marrow concentration, the marrow mesenchymal stem cell density could be enhanced, which is helpful in the reduction treatment course, enhances the curative effect, and plays a promotion role for bone fracture healing.
Because the marrow mesenchymal stem cells are easy to obtain, may induce to differentiate into many kinds of cells, and is easily stained by the exogenous gene extension and the stable expression, thus being considered as the best choice cells in tissues, but is not abundant in bone marrow, approximately composes the nucleated cells 0.001%-0.010%, therefore how to consummate the marrow mesenchymal stem cell's separation, to increase the high density, to obtain the good curative effect of bone marrow stem cell appears especially important. A simple, stable, highly effective system deserves further studying. Generally thought, the bone marrow mesenchymal stem cell's survival, proliferation and differentiation are influenced by the environments, such as peritonsillar tissue cells, characteristics of surface, partial blood supply, stress environment and so on. Some researches indicate that the in vitro environment does not favor the mesenchymal stem cell's long-term multiplication, the long-term culture will possibly weaken its synthesis collagen ability[27]. This experiment used the short-term concentration separated and purified bone marrow mesenchymal stem cell transplant treatment to heal bone nonunion, each kind of cells in bone marrow can separate in a short term according to the density difference, may enhance the acquisition rate of bone marrow mesenchymal stem cells, increase their purity, and simultaneously remove the red blood cells, which both can strengthen osteogenesis ability of bone marrow stem cells and reduce its active ability. In the clinical trials, the curative effect is reliable, stable, without obvious side effects. In this study, the curative effect of bone marrow transplant was enhanced, proving that the MSC density was related to the bone fracture healing, which was consistent with literature reported[1,5]. Further studies should focus on whether this research exist deficiency, how to obtain the concentration, the highly effective bone marrow mesenchymal stem cells and the dose-effect relations of healing the bone fracture.
This research uses fixation techniques, rather than the incision replacement, to fix bone marrow MSC transplant, the preliminary determination results are as follows: ① When internal fixation was over, external fixation cannot satisfy the requirement of bone fracture healing; ② The damage gap of bone fracture end was ≥ 10 mm, the hardening of bone fracture end was obvious. In clinical practice, bone damage and bone fracture end exhibited to be wide, thus needing the appropriate support material and the attachment of seed cells are the key of cell culture. The MSC concentration mixes with the appropriate support material, may served as MSCs carrier, is advantageous in maintaining the MSC density at bone fracture lesion, in enhancing partial bone formations, simultaneously playing the bone support role on filling the bone defects. The guided bone induction function may promote the bone formation in coordination with the MSC. At present, the decalcified bone displays the conduction ossification in the repairing process of bone defects, its structure and composition were similar with human body bone tissue, meeting the physiological requirement for the bone defect repairs, having the good biological compatibility and conduction ossification, may be used as the bone tissue engineering support material[28], effectively assist MSC's osteogenesis ability in clinical practice.
This experimental result indicated that, compared with the tradition treatment, bone marrow MSC transplant has the obvious superiority to heal bone nonunion, and reduce the treatment course, enhance the curative effect, and avoids medical dispute caused by the multiple surgery of bone fracture, without obvious side effects, have the broad prospect in the orthopedics clinical practice. After transplantation, more attentions should be paid on the question if fracture fixation is stable to avoid bone fracture recurrence, because the abnormal movement can cause the bone absorption and according results in bone nonunion.
