Objective To explore an improved reconstruction of the anterior crucial ligament (ACL) with the allograft hamstring fixed by the Rigidfix and Intrafix anchorages and to evaluate its therapeutic effectiveness in a short term. Methods The ACL reconstruction was performed under the arthroscope on 21 patients’ knees from Janaury 2006 to December 2006. There were 13 males and 8 females aged from 18 to 53 years. The injuries were caused by a traffic accident in 7 patients, a movement damage in 11, and other factors in 3. The medial collateral ligament(MCL) and the medial meniscus were injured in 10 patients, the medial meniscus andthe lateral meniscus were injured in 3, the lateral meniscus was injured in 6, and only the ACl was injured in 2. The operations were performed 7 days to 3 monhs after the injuries. The graft used was the fourstranded allograft hamstring, which was fixed by the Rigidfix and Intrafix anchorages. The therapeutic effect was evaluated according to the Lysholm rating scale. Results The follow-up of all the 21 patients for 3-9 months (average, 5.8 months) revealed that the knees of 19 patients could move beyond 120° after operation. In 1 patient who had the MCL injury, the range of genuflex was limited to 80° at 3 months after operation, and so the operation of lysis was performed under thearthroscope again. In 1 patient, the rejection against the allograft was treated by the irrigating under the arthroscope but had little effect. The anterior drawer test and the pivot shift test were negative in the 21 patients. During the Lanchman test, 1 patient had a positive result (Degree Ⅰ). The Lysholm scores were significantly increased from 56.73±6.58 to 88.14±7.02 (P＜0.01). Conclusion The surgical approach to reconstruction of ACL with the fourstranded allograft hamstring fixed by the Rigidfix and Intrafix anchorages is feasible and safe. The resulting fixation is reliable. The patients can begin their postoperative rehabilitation exercise earlier and their movement function can be restored earlier.
【Abstract】 Objective To investigate the secretion of target gene and differentiation of BMSCs transfected by TGF-β1 and IGF-1 gene alone and together into chondrocytes and to provide a new method for culturing seed cells in cartilage tissue engineering. Methods The plasmids pcDNA3.1-IGF-1 and pcDNA3.1-TGF-β1 were ampl ified and extracted, then cut by enzymes, electrophoresed and analyzed its sequence. BMSCs of Wistar rats were separated and purificated by the density gradient centrifugation and adherent separation. The morphologic changes of primary and passaged cells were observed by inverted phase contrast microscope and cell surface markers were detected by immunofluorescence method. According to the transfect situation, the BMSCs were divided into 5 groups, the non-transfected group (Group A), the group transfected by empty vector (Group B), the group transfected by TGF-β1 (Group C), the group transfected by IGF-1 (Group D) and the group transfected both by TGF-β1 and IGF-1 (Group E). After being transfected, the cells were selected, then the prol iferation activity was tested by MTT and expression levels were tested by RT-PCR and Western blot. Results The result of electrophoresis showedthat sequence of two bands of the target genes, IGF-1 and TGF-β1, was identical with the sequence of GeneBank cDNA. A few adherent cells appeared after 24 hours culture, typical cluster formed on the forth or fifth days, and 80%-90% of the cells fused with each other on the ninth or tenth days. The morphology of the cells became similar after passaging. The immunofluorescence method showed that BMSCs were positive for CD29 and CD44, but negative for CD34 and CD45. A few cells died after 24 hoursof transfection, cell clone formed at 3 weeks after selection, and the cells could be passaged at the forth week, most cells became polygonal. The boundary of some cells was obscure. The cells were round and their nucleus were asymmetry with the particles which were around the nucleus obviously. The absorbency values of the cells tested by MTT at the wavelength of 490 nm were0.432 ± 0.038 in group A, 0.428 ± 0.041 in group B, 0.664 ± 0.086 in group C, 0.655 ± 0.045 in group D and 0.833 ± 0.103 in group E. The differences between groups A, B and groups C, D, E were significant (P lt; 0.01). The differences between groups A and B or between C, D and E were not significant (P gt; 0.05)。RT-PCR and Western blot was served to detect the expression of the target gene and protein. TGF-β1 was the highest in group C, 0.925 0 ± 0.022 0, 124.341 7 ± 2.982 0, followed by group E, 0.771 7 ± 0.012 0, 101.766 7 ± 1.241 0（P lt; 0.01）; The expression of IGF-1 was the highest in group E, 1.020 0 ± 0.026 0, 128.171 7 ± 9.152 0, followed by group D, 0.465 0 ± 0.042 0, 111.045 0 ± 6.248 0 （P lt; 0.01）. And the expression of collagen II was the hignest in group E, 0.980 0 ± 0.034 0, 120.355 0 ± 12.550 0, followed by group C, 0.720 0 ± 0.026 0, 72.246 7 ± 7.364 0（P lt; 0.01）. Conclusion The repairment of cartilage defects by BMSCs transfected with TGF-β1 and IGF-1 gene together hasa good prospect and important significance of cl inic appl ication in cartilage tissue engineering.