Comparison of curative effect between OBS assisted by 3D printing and PFNA in the treatment of AO/OTA type 31-A3 femoral intertrochanteric fractures in elderly patients.

Objective: To compare and analyze the Ortho-Bridge System (OBS) clinical efficacy assisted by 3D printing and proximal femoral nail anti-rotation (PFNA) of AO/OTA type 31-A3 femoral intertrochanteric fractures in elderly patients. Methods: A retrospective analysis of 25 elderly patients diagnosed with AO/OTA type 31-A3 femoral intertrochanteric fracture was conducted from January 2020 to August 2022 at Yan'an Hospital, affiliated to Kunming Medical University. The patients were divided into 10 patients in the OBS group and 15 in the PFNA group according to different surgical methods. The OBS group reconstructed the bone models and designed the guide plate by computer before the operation, imported the data of the guide plate and bone models into a stereolithography apparatus (SLA) 3D printer, and printed them using photosensitive resin, thus obtaining the physical object, then simulating the operation and finally applying the guide plate to assist OBS to complete the operation; the PFNA group was treated by proximal femoral nail anti-rotation. The operation time, the intraoperative blood loss, Harris hip score (HHS), Oxford Hip Score (OHS), and complications were compared between the two groups. Results: The operation time and the intraoperative blood loss in the PFNA group were less than that in the OBS group, and there was a significant difference between the two groups (P < 0.05). The HHS during the 6th month using OBS was statistically higher than PFNA (P < 0.05), however, there were no significant differences in OHS during the 6th month between the OBS group and PFNA group (P > 0.05). The HHS and OHS during the 12th month in the OBS group were statistically better than in the PFNA group (P < 0.05). Conclusion: The OBS assisted by 3D printing and PFNA are effective measures for treating intertrochanteric fractures. Prior to making any decisions regarding internal fixation, it is crucial to evaluate the distinct circumstances of each patient thoroughly.

Knockdown of long noncoding RNA HOTAIR inhibits osteoarthritis chondrocyte injury by miR-107/CXCL12 axis.

BACKGROUND: Osteoarthritis (OA) is a joint disease characterized via destruction of cartilage. Chondrocyte damage is associated with cartilage destruction during OA. Long noncoding RNAs (lncRNAs) are implicated in the regulation of chondrocyte damage in OA progression. This study aims to investigate the role and underlying mechanism of lncRNA homeobox antisense intergenic RNA (HOTAIR) in OA chondrocyte injury. METHODS: Twenty-three OA patients and healthy controls without OA were recruited. Chondrocytes were isolated from OA cartilage tissues. HOTAIR, microRNA-107 (miR-107) and C-X-C motif chemokine ligand 12 (CXCL12) levels were measured by quantitative real-time polymerase chain reaction and western blot. Cell proliferation, apoptosis and extracellular matrix (ECM) degradation were measured using cell counting kit-8, flow cytometry and western blot. The target interaction was explored by bioinformatics, luciferase reporter and RNA immunoprecipitation assays. RESULTS: HOTAIR expression was enhanced, and miR-107 level was reduced in OA cartilage samples. HOTAIR overexpression inhibited cell proliferation, but induced cell apoptosis and ECM degradation in chondrocytes. HOTAIR knockdown caused an opposite effect. MiR-107 was sponged and inhibited via HOTAIR, and knockdown of miR-107 mitigated the effect of HOTAIR silence on chondrocyte injury. CXCL12 was targeted by miR-107. CXCL12 overexpression attenuated the roles of miR-107 overexpression or HOTAIR knockdown in the proliferation, apoptosis and ECM degradation. CXCL12 expression was decreased by HOTAIR silence, and restored by knockdown of miR-107. CONCLUSION: HOTAIR knockdown promoted chondrocyte proliferation, but inhibited cell apoptosis and ECM degradation in OA chondrocytes by regulating the miR-107/CXCL12 axis.

[Experimental research on repair of rabbit articular cartilage deffects with composite of autologous cell-carriers].

OBJECTIVE: To study the effect of the repair of rabbit articular cartilage defects by the composite of chondrogenic induction of autologous MSCs and autologous "two-phase" bone matrix gelatin (BMG). METHODS: Twenty-four healthy adult New Zealand rabbits weighing 2 to 3 kg were divided into group A, B and C with 8 in each. Autologous MSCs derived from group A were cultured in vitro and observed under inverted phase contrast microscope when enough cells through trypsinization transferring in vitro were obtained. Then the growth curves of 1, 3 and 5 passage culture of MSCs were drawn. The 3rd passage MSCs were induced into chondrogenic differentiation by adding TGF-beta1 (10 ng/mL), IGF-1 (10 ng/mL) and vitamin C (50 ng/mL) in vitro. At 8 days after induction, the features of chondrocytes were observed under inverted phase contrast microscope,and immunohistochemical staining and Mallory staining were made. Getting out part of the ilium of group A and B, according to the method of Urist, the "two-phase" BMG was acquired. Chondrogenic induction of autologous MSCs was inoculated into the corresponding BMG to set up a composite of cell-carrier, and then it was observed through scanning electric microscope after 3 days of culture. The model of articular cartilage defects of rabbits was made: in group A,autologous cell-carriers were implanted; in group B, there only existed autologous BMG; in group C,there was nothing. At 8, 12 weeks after operation, the gross, HE staining and immunohistochemical staining were made,and grading scales were evaluated according to Wakitani histological grading method. RESULTS: Features of MSCs were as follows: the shape of primary cells was shot-spindled and of passage cells was long. As to the growth curves of 1, 3 and 5 passage culture of MSCs,passage cells grew slowly for 3 days after being passaged and went into log-growth during the 3rd and the 7th days and into plateau later, but the 3rd passage cells grew best. Observation of MSCs after chondrogenic induction was performed: the shape of cells was elliptical and the effect of induction was verified by the positive results of collagen type II, S-100 and Mallory staining. Under scanning electric microscope,the structure of BMG was good and cells were observed growing in it well. As far as repair of articular cartilage defects are concerned at 8, 12 weeks after transplantation, the defects in group A were repaired by the hyline-like tissue and the structures of the cartilage surface and normal cartilage were in integrity,and immunohistochemical staining of collagen type II was positive, while those in group B and C were repaired by the fibrous-like tissues and the surfaces were irregular. In Wakitanni histological score, at 8 weeks after operation, group A was (3.50 +/- 1.51) points, group B was (10.00 +/- 1.41) points and group C was (12.00 +/- 0.93) points; at 12 weeks, group A was (1.13 +/- 0.99) points, group B was (8.38+/-1.30) points, and group C was (10.13 +/- 1.64) points. At different time points,group A was significantly better than group B and C, showing significant differences (P < 0.05). CONCLUSION: Induced autologous MSCs and the composite withautologous "two-phase" BMG have the function to repair articular cartilage defects, and they are better than autologous BMG transplanted only or nothing transplanted.