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Tibial plateau fractures (TPFs) are a challenging type of fracture in orthopedic traumatology. We previously designed a plate (Patent Number: CN201520195596.5) for posterolateral TPF combined with posterior lateral collapse.. In this study, finite element analysis was used to compare the biomechanical characteristics of two internal fixation methods for posterolateral TPF. We investigated the support effect of the new steel plate on lateral TPFs combined with posterior TPFs.Two models of complex TPF were established. Model A was fixed with the new type of plate, and model B was fixed without the plate. Three axial loads of 500, 1,000, and 1,500 N were applied using FEA on the two fracture models (A and B) to analyze the data.In model A, the maximum displacement at 500, 1,000, and 1,500 N was 0.085797, 0.17043, and 0.25465 mm, respectively; the maximum stress of the bone block was 11.285, 20.648, and 29.227 MPa, respectively; and the maximum strain of the bone block was 0.0012474, 0.007435, and 0.0035769 mm, respectively. The maximum displacement of the internal fixation was 0.096932, 0.18682, and 0.27655 mm, respectively; the maximum stress was 69.54, 112.1, and 155.71 MPa, respectively; and the maximum strain was 0.00066228, 0.0010676, and 0.0014829 mm, respectively. In model B, the maximum displacement of fractures at 500, 1,000, and 1,500 N was 0.15675, 0.29868, and 0.44017 mm, respectively; the maximum stress of the bone block was 6.5519, 12.575, and 18.842 MPa, respectively; and the maximum strain of the bone block was 0.0032554, 0.0074357, and 0.012146 mm, respectively. The maximum displacement of the screw was 0.14177, 0.27109, and 0.39849 mm, respectively; the maximum stress was 48.916, 92.251, and 135.27 MPa, respectively; and the maximum strain was 0.00046608, 0.00087893, and 0.0012887 mm, respectively.The fixation method using this type of plates and screws can replace other methods using two plates to fix complex TPF.

Background With increasing life expectancy, stem cell therapy is receiving increasing attention. However, its application is restricted by ethical concerns. Hence a need exists for design of safe procedures for stem cell procurement. Here, we investigated whether hemovac blood (HVB) is an appropriate stem cell source. Methods HVB concentrates (HVBCs) from 20 total knee arthroplasty (TKA) patients and bone marrow aspirate (BMA) concentrates (BMACs) from 15 patients who underwent knee cartilage repair were comparatively evaluated. A bone marrow aspiration needle was inserted into the anterior superior iliac spine. Aspiration was performed using a 50-mL syringe, including 4 mL of anticoagulant, followed by centrifugation to obtain BMACs. To obtain HVBCs, blood was aspirated from the hemovac immediately after TKA surgery. Different cell types were enumerated. Isolation of BMA and HVB mononuclear cells was performed using density gradient centrifugation. Non-hematopoietic fibroblast colonies were quantified by colony forming unit-fibroblast assay surface marker analysis of HVB, HVBC, BMA, and BMAC was performed via flow cytometry. Mesenchymal stem cells (MSCs) isolated from HVBCs and BMACs were examined for osteogenic, adipogenic, and chondrogenic differentiation potential. Gene expression analysis was performed by quantitative real-time polymerase chain reaction (qRT-PCR). Results The number of cells from HVB and HVBC was significantly lower than from BMA and BMAC; however, the number of colonies in HVBC and BMAC did not differ significantly (P>0.05). Isolated cells from both sources had a fibroblast-like appearance, adhered to culture flasks, and formed colonies. Under different culture conditions, MSC-specific surface markers (CD29, CD44, CD90, CD105), osteogenic markers [RUNX2, osteopontin, osteocalcin, and alkaline phosphatase (ALP)] and adipogenic markers (PPARγ and C/EBPα) were expressed. Moreover, SOX9, type II collagen, and aggrecan were significantly upregulated upon chondrogenic differentiation. Conclusions HVB from TKA patients is a useful source of stem cells for research.

Knee osteoarthritis (OA) is a leading cause of pain and disability. Although conventional treatments show modest benefits, pilot and phase I/II trials with bone marrow (BM) and adipose‐derived (AD) mesenchymal stromal cells (MSCs) point to the feasibility, safety, and occurrence of clinical and structural improvement in focal or diffuse disease. This study aimed to assess the safety and efficacy of the intra‐articular injection of single or repeated umbilical cord‐derived (UC) MSCs in knee OA. UC‐MSCs were cultured in an International Organization for Standardization 9001:2015 certified Good Manufacturing Practice‐type Laboratory. Patients with symptomatic knee OA were randomized to receive hyaluronic acid at baseline and 6 months (HA, n = 8), single‐dose (20 × 106) UC‐MSC at baseline (MSC‐1, n = 9), or repeated UC‐MSC doses at baseline and 6 months (20 × 106 × 2; MSC‐2, n = 9). Clinical scores and magnetic resonance images (MRIs) were assessed throughout the 12 months follow‐up. No severe adverse events were reported. Only MSC‐treated patients experienced significant pain and function improvements from baseline (p = .001). At 12 months, Western Ontario and Mc Master Universities Arthritis Index (WOMAC‐A; pain subscale) reached significantly lower levels of pain in the MSC‐2‐treated group (1.1 ± 1.3) as compared with the HA group (4.3 ± 3.5; p = .04). Pain Visual Analog scale was significantly lower in the MSC‐2 group versus the HA group (2.4 ± 2.1 vs. 22.1 ± 9.8, p = .03) at 12 months. For total WOMAC, MSC‐2 had lower scores than HA at 12 months (4.2 ± 3.9 vs. 15.2 ± 11, p = .05). No differences in MRI scores were detected. In a phase I/II trial (NCT02580695), repeated UC‐MSC treatment is safe and superior to active comparator in knee OA at 1‐year follow‐up. stem cells translational medicine 2019;8:215&224

Venous blood drained from the knee joint after total knee arthroplasty (TKA) using a hemovac line is a potential source of bone marrow components, including stem cells, from the cutting surface of cancellous bones of the knee joint. However, the function of mesenchymal stem cells (MSCs) in patients with osteoarthritis (OA-MSCs) can be disrupted by inflammation of the joint. Further, to override the invasive nature of the currently used methods to obtain stem cells, their functional modification is necessary for therapeutic applications. The effects of signal transducer and activator of transcription 3 (STAT3) signaling suppression on MSCs (iSTAT3-MSCs) were evaluated by comparative analyses of the characteristics of OA-MSCs and iSTAT3-MSCs from 20 patients who underwent TKA. OA-MSCs and iSTAT3-MSCs were adherent, with fibroblast-like appearance and high rates of expression of MSC-specific markers, including CD73, CD90, and CD105 (>90%). Both OA-MSCs and iSTAT3-MSCs were able to differentiate into osteogenic, adipogenic, and chondrogenic cells; however, iSTAT3-MSCs showed higher levels of osteogenic and chondrogenic differentiation markers than OA-MSCs. Additionally, the anti-inflammatory and chondroprotective cytokine levels were higher in iSTAT3-MSCs than in OA-MSCs. These findings indicate that iSTAT3-MSCs after TKA are potentially effective for stem cell therapy in the context of bone and cartilage disorders. [Abstract copyright: 2021 Annals of Translational Medicine. All rights reserved.]