Objective To determine whether the number of distal locking bolts have an impact on the biomechanical feature of locking intramedullary nails. Methods Twenty locking nails tested were divided into two groups randomly. One distal locking screw was used in first group (single bolt group); and two were used in the other group (double bolts group). After being fixed in the model, compressive and torsional strength of the interlocking nail were measured in each group. Results The average maximum strength of double bolts group and single bolt group was 2 160 N and 1 880 N respectively in compression tests(P＜0.05). In torsion tests, the average maximum torsional moment of double bolts group and single bolt group was 55.8 Nm and 55.5 Nm respectively(P＞0.05), the average maximum torsional angle indouble bolts group and single bolt group was 58.3° and 58.0° respectively(P＞0.05). Conclusion Single distal bolt used in interlocking nail system can meet clinical request, though the whole biomechanical behavior isnot better than that of double bolts. One distal bolt is enough for the stable fracture types and double bolts should be used in the serious fracture types.
Objective To investigate the effect difference between the Solis fixation fusion and the titanium plate fixation by the cervical anterior approach after decompression and bone graft implantation. Methods Of the 104 patients with cervical disease from September 2001 to March 2004, 36 were treated with the Solis implantation after decompression by the cervical anterior approach, and 68 were treated with the titanium plate fixation after decompression and bone graft implantation. The recovery of the neurological function in all the patients were assessed with the JOA Scoring at 6 weeks,3,6,12,24 and 36 months. The fragment fusion and its stability as well as the changes in the intervertebral height were assessed with X-ray examination. Results According to the JOA Scoring, the excellent and good outcomes accounted for 94.4% in the Solis group and 94.1% in the titanium plate group. In allthe patients, the fragment fusion was achieved in 3 months. The change in the Cobb angle of the fused fragment was less than 5° at the flexionextension posture, 3.6±0.8° in the Solis group, 2.4±0.7° in the titanium plate group. There was significant differences between the two groups(P＜0.05). The intervertebral height of the operation fragment in the Solis group increased 1.6±0.7mm, which was higher than that in the titanium plate group(P＜0.05). Conclusion Clinical effects of the two internalfixation operations are good; however, the Solis fixation has more advantages because of its simpler performance,less trauma, and fewer complications.
Objective To study the time effect of the gene expression of recombinant adeno-associated virus (rAAV) vector co-expressing human vascular endothel ial growth factor 165 (hVEGF165) and human bone morphogenetic protein 7 (hBMP-7) genes so as to lay a theoretical foundation for gene therapy of osteonecrosis. Methods The best multipl icity of infection (MOI) of BMSCs transfected with rAAV was detected by fluorescent cell counting. The 3rd generation rabbit bone mesenchymal stem cells (BMSCs) were transfected with rAAV-hVEGF165-internal ribosome entry site (IRES)-hBMP-7 (experimental group) and green fluorescent protein (GFP) labeled rAAV-IRES-GFP (control group), respectively. The expression of GFP was observed by inverted fluorescent microscope. The expressions of hVEGF165 and hBMP-7 were assessed by RT-PCR assay and Western blot assay in vitro. The transfected cells in 2 groups were prepared into suspension with 5 × 106 cells/mL, and injected into the rabbit thigh muscles of experimental group 1 (n=9) and control group 1 (n=9), respectively. The muscle injected with rAAV-IRES-GFP was sl iced by frozen section method and the expression of GFP protein was observed by inverted fluorescent microscope. The expressions of hVEGF165 and hBMP-7 were assessed by Western blot assay and ELISA assay in vivo. Results The best MOI of BMSCs transfected with rAAV was 5 × 104 v.g/cell. In vitro, the expressions of GFP, hVEGF165, and hBMP-7 genes started at 1 day after transfection, the expressions obviously increased at 14 days after transfection, and the expression maintained the b level at 28 days after transfection. In vivo, the expressions of GFP, hVEGF165, and hBMP-7 genes could be detected at 2 weeks after injection, and b expressions were shown at 6 to 8 weeks after injection. The values of hVEGF165 and hBMP-7 were (248.67 ± 75.58) pg/mL and (4.80 ± 0.61) ng/mL respectively in experimental group 1, and were (32.28 ± 8.42) pg/mL and (0.64 ± 0.42) ng/mL respectively in control group 1; showing significant differences between 2 groups (P lt; 0.05). Conclusion The rAAV-hVEGF165-IRES-hBMP-7 has efficient gene expression ability.
目的 觀察評價鹽酸氨基葡萄糖結合塞來昔布治療膝骨關節炎（KOA）的療效及安全性。 方法 2001年3月－2012年3月采用隨機對照方法，將184例KOA患者隨機分為對照組與試驗組，各92例。對照組單獨給予塞來昔布，試驗組給予塞來昔布和鹽酸氨基葡萄糖，共治療8周，停藥后繼續觀察4周。采用Lequesne指數作為療效評分標準，觀察服藥前后的膝關節癥狀變化，包括休息痛、運動痛、壓痛、腫脹、晨僵和行走能力的改善程度，紀錄不良反應及實驗室生化指標等。 結果 兩組Lequesne指數在治療前相比均明顯下降，兩組治療8周后Lequesne總指數比較差異均有統計學意義（P＜0.05）。治療8周后試驗組總有效率明顯優于對照組。安全性方面兩組比較無差異。 結論 鹽酸氨基葡萄糖結合塞來昔布治療KOA，能明顯改善患者的臨床癥狀，療效優于單純的塞來昔布治療，且不會增加藥物不良反應，具有較好的臨床價值。
ObjectiveTo investigate whether exosomes derived from miR-27a-overexpressing human umbilical vein endothelial cells (HUVECs)—exo (miR-27a) can promote bone regeneration and improve glucocorticoids (GC) induced osteonecrosis of femoral head (ONFH) (GC-ONFH).MethodsThe exo (miR-27a) were intended to be constructed and identified by transmission electron microscopy, nanoparticle tracking analysis, Western blot, and real-time fluorescent quantitative PCR (qRT-PCR). qRT-PCR was used to evaluate the effect of exo (miR-27a) in delivering miR-27a to osteoblasts (MC3T3-E1 cells). Alkaline phosphatase staining, alizarin red staining, and qRT-PCR were used to evaluate its effect on MC3T3-E1 cells osteogenesis. Dual-luciferase reporter (DLRTM) assay was used to verify whether miR-27a targeting Dickkopf WNT signaling pathway inhibitor 2 (DKK2) was a potential mechanism, and the mechanism was further verified by qRT-PCR, Western blot, and alizarin red staining in MC3T3-E1 cells. Finally, the protective effect of exo (miR-27a) on ONFH was verified by the GC-ONFH model in Sprague Dawley (SD) rats.ResultsTransmission electron microscopy, nanoparticle tracking analysis, Western blot, and qRT-PCR detection showed that exo (miR-27a) was successfully constructed. exo (miR-27a) could effectively deliver miR-27a to MC3T3-E1 cells and enhance their osteogenic capacity. The detection of DLRTM showed that miR-27a promoted bone formation by directly targeting DDK2. Micro-CT and HE staining results of animal experiments showed that tail vein injection of exo (miR-27a) improved the osteonecrosis of SD rat GC-ONFH model.Conclusionexo (miR-27a) can promote bone regeneration and protect against GC-ONFH to some extent.
Objective To compare the early rehabilitation effects of total hip arthroplasty (THA) with direct anterior approach (DAA) versus posterior approach (PA). Methods A retrospective analysis was made in the data of 83 patients with unilateral osteonecrosis of the femoral head between March 2014 and May 2017. Forty-eight patients were treated with THA via PA (PA group) and 35 patients were treated with THA via DAA (DAA group). There was no significant difference in gender, age, body mass index, stage of osteonecrosis of the femoral head, and disease duration between 2 groups (P>0.05). The length of incision, operation time, total amount of bleeding, the time of first postoperative walking with crutch, the time of first postoperative walking without crutch, the Harris scores, and the visual analogue scale (VAS) scores of 2 group were recorded and compared. Results All incisions healed primarily and no infection, dislocation, or fracture occurred. All patients were followed up 30.2 months on average (range, 6-44 months). The numbness symptom caused by the lateral femoral cutaneous nerve injury occurred in 2 patients of DAA group and released after symptomatic treatment. The length of incision, total amount of bleeding, the time of first postoperative walking with crutch, and the time of first postoperative walking without crutch of DAA group were significantly superior to those of PA group (P<0.05). The Harris scores of DAA group were significantly higher than those of PA group at 2 weeks and 1 month after operation (P<0.05), while no significant difference was found between 2 groups before operation and at 3 months and 6 months after operation (P>0.05). The VAS scores of DAA group were significantly lower than those of PA group at 1 day, 4 days, 1 week, and 2 weeks after operation (P<0.05), while no significant difference was found between 2 groups before operation (P>0.05). Conclusion DAA is meaningful to enhanced recovery after THA. But it should be chosen carefully because of the disadvantages, such as long learning curve, limited indications, and requirements of specific instruments.
Objective To analyze the biomechanical changes of the adjacent cervical facet joints when the angled cervical prosthesis is replaced. Methods A total of 400 northwestern people were involved, with an age of 40 years or older.The cervical vertebra lateral X-ray films were taken, and the cervical angles were measured by professional computer aided design software, then the cervical intervertebral disc prosthesis with 10° angle was designed. The finite element models of C4，5and C4-6 segments with intact cervical discs were developed; the C4，5 disc was replaced by the cervical prosthesis with 0° and 10° angle respectively; and then all models were subjected to axial loading, flexion/extension, lateral bending, and torsion loading conditions; the stress effects on adjacent facet joints after replacement were observed by comparing with that of the intact model. Results The cervical angles were (9.97 ± 3.64)° in C3，4, (9.95 ± 4.34)° in C4，5, (8.59 ± 3.75)° in C5，6, and (8.49 ± 3.39)° in C6，7, showing no significant difference between C3，4 and C4，5, C5，6 and C6，7 (P gt; 0.05) and showing significant differences between the other cervical angles (P lt; 0.05). When C4，5 model was axially loaded, no significant difference in equivalent shearing stress were observed in intact, 0°, and 10° groups; at flexion/extension loading, the stress was biggest in intact group, and was smallest in 10° group; at lateral bending, the stress got the high rank in intact group, and was minimum in 10° group; at torsion loading, the stress state of 10° group approached to the intact one condition. When C4-6 model was loaded, the facet joint stress of the replaced segment (C4，5) decreased significantly at axial loading, flexion/extension, and lateral bending; while no obvious decrease was observed at torsion loading; the stress of the adjacent inferior disc (C5，6) decreased significantly at axial loadingand lateral bending condition, while less decrease was observed at torsion loading, no significant change at flexion/extension condition, it approached to that of the intact one. Conclusion The finite element analysis reveals that the biomechanical properties of 10° designed prosthesis is approximate to that of the intact cervical disc, thus the 10° designed prosthesis can meet the requirements of biomechanical function reconstruction of the cervical spine.
Objective To construct and screen neurite outgrowth inhibitory 66-samll interfering RNA (nogo66-siRNA) eukaryotic expression vectors of effective interference, so as to lay a foundation for further reconstruction of related viral vector. Methods? The nogo66-siRNA fragments were designed and cloned into pGenesil-1.1, 4 plasmids of pGenesil-nogo66-siRNA-1, pGenesil-nogo66-siRNA-2, pGenesil-nogo66-siRNA-hk, and pGenesil-nogo66-siRNA-kb were obtained, sequenced and identified, then were transfected into C6 cell l ine. The transfection efficiency was measured by fluorescence microscope. RT-PCR and Western blot were used to detect the expression of nogo gene and select the plasmid of effective interference. Results DNA sequencing results showed interference sequences were correct. The bands of 800 bp and 4.3 kb were detected when pGenesil-nogo66-siRNAs were digested by Kpn I /Xho I. The expression of green fluorescent protein could be detected under fluorescence microscope, and the transfection efficiency was about 73%. RT-PCR and Western blot results showed that compared to non-transfected cells, the transfection of pGenesil-nogo66-siRNA-1 made the expression of nogo gene decl ine 22% and the expression of nogo protein decl ine 73%; the transfection of pGenesil-nogo66-siRNA-2 made the expression of nogo gene decl ine 28% and the expression of nogo protein decl ine 78%; the differences were significant (P lt; 0.05); and the transfection of pGenesil-nogo66-siRNA-hk and pGenesil-nogo66- siRNA-kb did not make the expressions of nogo gene and nogo protein decrease significantly (P gt; 0.05). Conclusion Nogo66-siRNA eukaryotic expression vector is successfully constructed, it lays an experimental foundation for repair of spinal cord injury.
ObjectiveTo compare the short-term effectiveness between arthroscopic cystectomy and internal drainage combined with cystectomy in popliteal cyst.MethodsBetween March 2014 and March 2017, 56 patients with symptomatic popliteal cyst were enrolled in the study, randomized block design was used to divided the patients into trial group (arthroscopic cystectomy combined with internal drainage group, n=28) and control group (arthroscopic internal drainage group, n=28). Excluding those who had incomplete follow-up and received surgery for other diseases postoperatively, 26 patients in the experimental group and 27 patients in the control group were finally enrolled in the study. There was no significant difference in gender, age, side, course of disease, maximum diameter and grade of popliteal cyst, and associated diseases between two groups (P>0.05). The operation time, duration of popliteal ecchymosis and the middle back of calf tenderness were observed postoperatively. The circumference of calf at 1 day, 1 week, and 2 weeks after operation were measured and the differences were calculated with the measurement before operation. Lower extremity venous thrombosis was observed by color doppler ultrasonography at 1 week after operation. The effectiveness was evaluated by Rauschning and Lindgren grading criteria. And MRI was used to observe whether the popliteal cyst disappeared or decreased and measured its maximum diameter at 1 year after operation.ResultsPatients in both groups were followed up 12-14 months, with an average of 12.5 months. The operation time, duration of popliteal ecchymosis, and the middle back of calf tenderness of the trial group were all longer than those in the control group (P<0.05), the differences of circumference of calf at 1 day, 1 week, and 2 weeks after operation of the trial group were greater than those in the control group (P<0.05). Color doppler ultrasonography of the lower extremity at 1 week after operation found that the intermuscular venous thrombosis occurred in 2 cases of the trial group, while no lower extremity thrombosis was found in the control group; and the difference between two groups was not significant (P=0.236). According to the Rauschning and Lindgren grading criteria, there were 16 cases of grade 0, 6 cases of grade 1, and 4 cases of grade 2 in the trial group, and 17 cases of grade 0, 4 cases of grade 1, and 6 cases of grade 2 in the control group at 1 year after operation. There was no significant difference between 2 groups (Z=–1.872, P=0.078). Nine cases (34.62%) of the trial group and 13 cases (48.15%) of the control group still have residual cysts by MRI, the maximum diameter of which was less than 2 cm. The cysts disappeared in the remaining patients in both groups, and there was no recurrence during the follow-up. There was no significant difference in cyst residual rate between 2 groups (χ2=2.293, P=0.852).ConclusionCompared with arthroscopic internal drainage, the short-term effectiveness of the arthroscopic internal drainage combined with cystectomy had no significant improvement, and the operation time was prolonged, the postoperative complications were obviously increased.
Objective To evaluate the effect of pneumatic tourniquet on perioperative period of total knee arthroplasty (TKA). Methods The perioperative period data of 116 patients over 60 years old with severe knee osteoarthritis treated with TKA between January 2018 and January 2019 were retrospectively analyzed. According to whether pneumatic tourniquet was used during operation, the patients were divided into trial group (49 cases, pneumatic tourniquet was not used during operation) and control group (67 cases, pneumatic tourniquet was used during operation). There was no significant difference in gender, age, body mass index, lesion side, disease duration, and preoperative hemoglobin between the two groups (P>0.05). The operation time, actual total blood loss, overt blood loss, hidden blood loss, and percentage of hidden blood loss, knee swelling at 3 days after operation, and range of motion of knee at 2 weeks after operation were recorded and compared between the two groups. Results The operation time of the trial group was significantly longer than that of the control group (t=14.013, P=0.000). The actual total blood loss, hidden blood loss, and percentage of hidden blood loss in the trial group were significantly lower than those in the control group (P<0.05); there was no significant difference in the overt blood loss between the two groups (t=?1.293, P=0.200). The knee swelling degree in the trial group was significantly slighter than that in the control group at 3 days after operation, and the range of motion of knee in the trial group was significantly better than that in the control group at 2 weeks after operation (P<0.05). Conclusion Pneumatic tourniquet can reduce the operation time of TKA significantly. However, it may increase the hidden blood loss and knee swelling, and negatively impact the recovery of knee function in the early postoperative stage of TKA.