Combined computational analysis and cytology show limited depth osteogenic effect on bone defects in negative pressure wound therapy.

Background: The treatment of bone defects remains a clinical challenge. The effect of negative pressure wound therapy (NPWT) on osteogenesis in bone defects has been recognized; however, bone marrow fluid dynamics under negative pressure (NP) remain unknown. In this study, we aimed to examine the marrow fluid mechanics within trabeculae by computational fluid dynamics (CFD), and to verify osteogenic gene expression, osteogenic differentiation to investigate the osteogenic depth under NP. Methods: The human femoral head is scanned using micro-CT to segment the volume of interest (VOI) trabeculae. The VOI trabeculae CFD model simulating the bone marrow cavity is developed by combining the Hypermesh and ANSYS software. The effect of trabecular anisotropy is investigated, and bone regeneration effects are simulated under NP scales of -80, -120, -160, and -200 mmHg. The working distance (WD) is proposed to describe the suction depth of the NP. Finally, gene sequence analysis, cytological experiments including bone mesenchymal stem cells (BMSCs) proliferation and osteogenic differentiation are conducted after the BMSCs are cultured under the same NP scale. Results: The pressure, shear stress on trabeculae, and marrow fluid velocity decrease exponentially with an increase in WD. The hydromechanics of fluid at any WD inside the marrow cavity can be theoretically quantified. The NP scale significantly affects the fluid properties, especially those fluid close to the NP source; however, the effect of the NP scale become marginal as WD deepens. Anisotropy of trabecular structure coupled with the anisotropic hydrodynamic behavior of bone marrow; An NP of -120 mmHg demonstrates the majority of bone formation-related genes, as well as the most effective proliferation and osteogenic differentiation of BMSCs compared to the other NP scales. Conclusion: An NP of -120 mmHg may have the optimal activated ability to promote osteogenesis, but the effective WD may be limited to a certain depth. These findings help improve the understanding of fluid mechanisms behind NPWT in treating bone defects.

Do stress fractures induce hypertrophy of the grafted fibula? A report of three cases received free vascularized fibular graft treatment for tibial defects.

The presence of large segmental defects of the diaphyseal bone is challenging for orthopedic surgeons. Free vascularized fibular grafting (FVFG) is considered to be a reliable reconstructive procedure. Stress fractures are a common complication following this surgery, and hypertrophy is the main physiological change of the grafted fibula. The exact mechanism of hypertrophy is not completely known. To the best of our knowledge, no studies have examined the possible relationship between stress fractures and hypertrophy. We herein report three cases of patients underwent FVFG. Two of them developed stress fractures and significant hypertrophy, while the remaining patient developed neither stress fractures nor significant hypertrophy. This phenomenon indicates that a relationship may exist between stress fractures and hypertrophy of the grafted fibula, specifically, that the presence of a stress fracture may initiate the process of hypertrophy.

Vascularised greater trochanter bone graft, combined free iliac flap and impaction bone grafting for osteonecrosis of the femoral head.

PURPOSE: To investigate the curative efficacy of osteonecrosis of the femoral head (ONFH) in a hip-preserving operative approach, by grafting a vascularized greater trochanter flap combined with a free iliac flap, in an attempt to seek an innovative approach for patients who suffered middle to late stage ONFH without total hip arthroplasty (THA) surgery. METHOD: Our research included a total of 60 patients (66 hips) who accepted hip-preserving surgery by grafting a vascularized greater trochanter flap combined with a free iliac flap which was tightly filled by hammering because of ONFH (most were Association Research Circulation Osseous (ARCO) stage III patients) from January, 2006 to December, 2010. A Harris Hip Score was obtained during follow-ups, evaluating the clinical efficacy, X-rays were taken regularly for image assessing, and the SF-36 scale was used for estimating quality of life. Terminal observation time was considered when patients had symptom-dependant indications for performing another hip-preserving surgery or THA surgery. RESULTS: Fifty-eight patients (64 hips) were eventually contacted by telephone for an out-patient clinic return visit, with a mean follow-up time of 35.8 months (varied from 12 months to 60 months), but two patients lost contact for various reasons. The demographic data were as follows: there were 16 ARCO IIIA cases, 22 ARCO IIIB cases, and 26 ARCO IIIC cases, respectively. Postoperative X-rays revealed a well-repaired necrotic area of the femoral head and improvement of femoral-acetabulum coverage. The last follow-up mean Harris Hip Score was 86.56 ± 7.38 (excellent results reached 87.50%), which were greatly improved compared to 50.95 ± 6.86 pre-operatively. Also the postoperative mean scores of all dimensions of the SF-36 scale were improved to some extent. Additionally the physical component summary (PSC) scores were enhanced from 42 ± 13 pre-operatively to 78 ± 11, while the postoperative mental component summary (MCS) scores (76 ± 11) largely increased in contrast to pre-operative scores (51 ± 10), with both target indices having statistical significance (p = 0.005, p = 0.01), signifying hugely improvement of the quality of life of the patients. A correlation was found between Harris Hip Score and all dimensions of SF-36 scale (r = 0.32-0.72), especially closely correlated with physical functioning (PF), role-physical (RP) and bodily pain (BP) in PCS aspect (r = 0.72, p < 0.01; r = 0.58, p < 0.01; r = 0.65, p < 0.01, respectively). CONCLUSION: There is definite curative efficacy for the treatment of ONFH with an hip-preserving operative approach by grafting a vascularized greater trochanter flap combined with a free iliac flap which was tightly filled by hammering. This kind of operative approach reconstructs the biological stability of femoral head, which promotes repair of necrotic areas and indirectly preserves the femoral head of patients and a majority of hip function. It possesses vast clinical as well as practical significance, because the long-term efficacy can satisfy fundamental life requirements, especially for those young and middle-aged patients who suffer ONFH to avoid or put off the time of total hip arthroplasty (THA) surgery.

[Experimental study of directional differentiation of bone mesenchymal stem cells (BMSCs) to osteoblasts guided by serum containing cistanche deserticola].

OBJECTIVE: To study directional differentiation of BMSCs guided by Desert living Cistanche (Herba Cistanches) which invigorates the kidney. METHODS: Primary BMSCs were obtained by whole bone marrow culture and subcultured to the fourth generation by trypsin digestion, and than inoculated into two six-well plates at 5 x 10(6) cells per milliliter, all the plates were divided into three groups as blank group, Dexamethasone (DXM) group and Herba Cistanches group, three wells in each group, medium were changed at day 2. The blank group were changed with L-DMEM containing 10% FBS. The DXM group were changed with medium containing 10 mmol/L beta-sodium glycerophosphate, 0.1 micromol/L DXM and 50 mg/L vitamin C. The Herba Cistanches group were changed with medium containing 10% blood serum containing Herba Cistanches and L-DMEM. One of the six-well plates was stained by alkaline phosphatase (AKP) at the tenth day,the other one was stained by alizarin Bordeaux at the twentieth day. RESULTS: At the tenth day DXM group and Herba Cistanches group were ALKP stained positive; from the 12th day,white calcium nodus could be seen at the surface of the wells; which alizarin stained positive by the twentyth day. CONCLUSION: The medium containing Herba Cistanches can guide BMSCs to differentiate into osteoblast, which promises a favorable prospect for the treatment of osteoporosis and bone fracture disunion.

[Human osteoblast-like cells OS-732 intervened with alcohol and treated with liuweidihuang pill medicated serum].

OBJECTIVE: To investigate the mechanism of osteonecrosis of the femoral head caused by alcohol and the therapeutic effects of the method of invigorating the kidney. METHODS: The osteoblast-like cells were intervened with 0.3, 0.9, 1.5 mol/L alcohol and observed by flow cytometry and light microscopy and electro microscopy. The cells intervened by 0.15 mol/L alcohol were treated with liuweidihuang pill medicated serum and observed by flow cytometry and light microscopy and electro microscopy. RESULTS: Apoptosis rate and the degree of cell necrosis had positive correlation with the concentration and the acting time of alcohol. The polymorphism of cells wer turned into roundness, and the cellular ecphyma was shortened and thinning, ribosome and endocytoplasmic reticulum were diminished. Part of the ruffle in mitochondria was disappeared. After treatment, the cellular ecphyma was recovered and the endoplasmic reticulum and golgi apparatus were visible. CONCLUSION: The osteoblast-like cells could be necrosis and apoptosis by the alcohol and were positive correlation with the intervened concentration and acting time. Chinese medicine with method of invigorating the kidney has effect on rehabilitating the cellular activity.

[Treatment for ipsilateral fractures of the femoral neck and shaft].

OBJECTIVE: To investigate the curative effect of different internal fixation for ipsilateral fractures of the femoral neck and shaft. METHODS: By retrospective study of 27 patients who sustained ipsilateral femoral shaft and neck fractures from June 1993 to March 2004. There were 22 male and 5 female, with an average age of 35 years (range in 14 to 65 years). The femoral neck and shaft fractures were stabilized with dynamic hip screw system (DHS) in 3 cases,with dynamic compression plate and cannulated lag screw in 12 cases, with constructive nail in 8 cases, with antegrade intramedullary locking nail and cannulated lag screw in 4 cases. There were 13 cases used of the temporary fixation of Kirschner wire before the pexia of the femoral neck fractures. RESULTS: All of the patients were followed up for 36 to 75 months, with an average of 44 months. The average healing period of femoral neck fracture was 4.5 months in 25 cases, nonunion of femoral neck fractures in 2. The average healing period of femoral shaft fracture was 6 months in 27 cases. In 14 cases that not using temporary fixation of femoral neck with Kirschner wire, there were nonunion of femoral neck in 2 and slight coxa vara in 3. CONCLUSION: There are a wide choice of internal fixation method for treatment of ipsilateral fracture of the femoral neck and shaft, the fixation with dynamic compression plate and cannulated lag screw is a handy method. It would be avoided to the replacement and trauma, emporary fixing the fracture with Kirschner wire before the pexia of the femoral neck fracture.

[Effects of Shengmai Chenggu capsule on proliferation and vascular endothelial growth factor secretion of vascular endothelial cells].

OBJECTIVE: To study the effect of the serum of rabbits fed with Shengmai Chenggu capsule (SMCGC), a preparation of traditional Chinese medicine, on the proliferation and vascular endothelial growth factor (VEGF) secretion of cultured ECV304 cells. METHODS: The drug-containing serum from rabbits with intragastric administration of SMCGC at different doses was obtained for treatment of ECV304 cells cultured in vitro, with the cells treated with blank serum and ligustrazine serving as the control. The proliferation of ECV304 cells was detected by MTT assay and VEGF concentration in the culture medium of the cells measured by means of ELISA. The ultrastructure of ECV304 cells treated with the sera for 12 h was observed by transmission electron microscopy. RESULTS: After treatment with SMCGC-containing rabbit serum for 12 and 36 h, respectively, the proliferation of ECV304 cells in all dosage groups showed no significant increases (P>0.05), and the sera of rabbits fed with medium and high doses of SMCGC significantly inhibited the proliferation of ECV304 cells after a 36-hour treatment (P<0.01). The high-dose rabbit serum might even cause apoptosis of ECV304 cells, and low-dose serum significantly stimulated VEGF secretion of the ECV304 cells (P<0.01). CONCLUSIONS: SMCGC does not promote the proliferation of ECV304 cells, and the serum of low-dose SMCGC-treated rabbits may stimulate VEGF secretion of the ECV304 cells, which might be the main mechanism of SMCGC in stimulating angiogenesis.