Objective To investigate the curative effect of arthroscopic treatment for lateral dis-cord meniscus tear in children. Methods The study involved 229 child patients with lateral discord meniscal tear treated arthroscopically from March 1996 to March 2008. There were 133 males and 96 fe-males, at age of (9±3.5) years (range 4-14 years). The treatment methods included meniscus-plasty in 219 patients (including two children with postoperative recurrence), meniscus-plasty-suture in eight and partial meniscectomy in two. The function of the knees was assessed pre-operationally and post-operation-ally by using Lysholm score. Results Of all, 221 patients were followed up for a period of (65±48.9) months (range 5-144 months). The pain and swelling were alleviated, with obvious improvement in range of motion and knee function in all patients six months after operation. There were no complica-tions including intra-articular infection, iatrogenic injury, fibroarthritis or loss of range of motion. Ly-sholm score was (61.85±7.65) points (range 45-73) before operation, which was improved to (95.30±3.50) points (range 87-100 points) six months after operation (t= 26.778, P < 0.01). Conclusion Treatment of lateral discord meniscus tear under arthroscopic guidance in children has the advantages of minor trauma, satisfactory results, can maintain good shape of the meniscus and good func-tion of knee and reduce incidence rate of osteoarthritis.

Objective To compare the curative effect and biomechanical performance of cannulated compression screw (CCS) and dynamic hip screw-blade (DHS-B) in the treatment of patients with femoral neck fracture.Methods Between February 2010 and February 2014,102 patients with femoral neck fracture were treated with CCS or DHS-B at our department.They were 54 males and 48 females,aged from 15 to 86 years.There were 30 subcapital fractures,51 transcervical ones and 21 base ones.CCS was used in 60 patients and DHS-B in 42.In-hospital data were collected retrospectively to compare the curative effects in 2 groups.Furthermore,femoral neck fracture models were established using 12 adult cadaveric femoral specimens.The 12 models were randomized into 2 equal groups (n =6).Group A was subjected to fixation by 3 CCSs and group B to fixation by DHS-B.The 2 groups were compared in terms of axial loading test,rotation test and destructive axial loading test.Results The operation time (59.4 ± 20.2 min),incision size (4.1 ±0.6 cm) and intraoperative blood loss (25.9 ±9.9 mL) in the CCS group were significantly less than those in the DHS-B group (88.6±22.9 min,12.1 ±1.2cmand 156.7±107.1 mL) (P ＜0.05).The Harris hip score for the DHS-B group (91.9±9.8) was significantly higher than that for the CCS group (87.2 ± 9.2) (P ＜ 0.05).There were no significant differences between the 2 groups in hospital stay,partial weight-bearing time,or postoperative complications (P ＞ 0.05).At 500 N vertical loading,the stress values at both medial and lateral sides of the femur in group A were significantly smaller than those in group B (P ＜ 0.05).There were no significant differences between groups A and B in the average sinking displacement of femoral head or the torque at a torsion angle of 6° (P ＞ 0.05).The maximum load in group A (2,135 ±120 N) was significantly smaller than that in group B (2,986 ± 98 N) (P ＜ 0.05).Conclusion In treatment of femoral neck fracture,DHS-B fixation is obviously superior to CCS fixation,because the former is in better agreement with the femoral biomechanical property,and performs better in anti-rotation and anti-compression,leading to better functional recovery of the affected hip.

Objective: To investigate the mode of cell death caused by NDV strain Changchun and NDV strain Siping. Methods: Plaque formation, cell suppression test, gel electrophoresis, and TUNEL assay were used after the cells were infected by NDV. Results: The apparently pathological changes were observed in chicken embryo fibroblasts, BHK, Hela, Hep 2, HCT and OS 732 tumor cells, but not in Wish cells. The higher suppressed effect on tumor cells was found in the NDV strain Changchun than that in the NDV strain Siping. There was no dose effect relationship between NDV and tumor cell suppression, only optimum dose NDV could cause maximal tumor cells inhibitory effect. Conclusion: The mode of cell death might be different after infection of NDV. The NDV strain Changchun killed tumor cells mainly through apoptosis, while the NDV strain Siping killed tumor cells mainly through necrosis. \[