BACKGROUND:The aim of this study was to design and test a novel composite scaffold with antibacterial efficacy for treating bone infections using a three-dimensional (3D) printed poly(ε-caprolactone) (PCL) scaffold coated with polydopamine (PDA) for...

Scaffolds play an important role in directing three-dimensional (3D) cartilage regeneration. Our recent study reported the potential advantages of bone marrow clots (MC) in promoting extracellular matrix (ECM) scaffold chondrogenic regeneration. The aim of this study is to build a new scaffold for MC, with improved characteristics in mechanics, shaping, and biodegradability, compared to our previous study. To address this issue, this study prepared a 3D porous polycaprolactone (PCL)-hydroxyapatite (HA) scaffold combined with MC (Group A), while the control group (Group B) utilized a bone marrow stem cell seeded PCL-HA scaffold. The results of in vitro cultures and in vivo implantation demonstrated that although an initial obstruction of nutrient exchange caused by large amounts of fibrin and erythrocytes led to a decrease in the ratio of live cells in Group A, these scaffolds also showed significant improvements in cell adhesion, proliferation, and chondrogenic differentiation with porous recanalization in the later culture, compared to Group B. After 4 weeks of in vivo implantation, Group A scaffolds have a superior performance in DNA content, Sox9 and RunX2 expression, cartilage lacuna-like cell and ECM accumulation, when compared to Group B. Furthermore, Group A scaffold size and mechanics were stable during in vitro and in vivo experiments, unlike the scaffolds in our previous study. Our results suggest that the combination with MC proved to be a highly efficient, reliable, and simple new method that improves the biological performance of 3D PCL-HA scaffold. The MC-PCL-HA scaffold is a candidate for future cartilage regeneration studies.

It is well known that implanting a bioactive scaffold into a cartilage defect site can enhance cartilage repair after bone marrow stimulation (BMS). However, most of the current scaffolds are derived from xenogenous tissue and/or artificial polymers. The implantation of these scaffolds adds risks of pathogen transmission, undesirable inflammation, and other immunological reactions, as well as ethical issues in clinical practice. The current study was undertaken to evaluate the effectiveness of implanting autologous bone marrow mesenchymal stem cell-derived extracellular matrix (aBMSC-dECM) scaffolds after BMS for cartilage repair. Full osteochondral defects were performed on the trochlear groove of both knees in 24 rabbits. One group underwent BMS only in the right knee (the BMS group), and the other group was treated by implantation of the aBMSC-dECM scaffold after BMS in the left knee (the aBMSC-dECM scaffold group). Better repair of cartilage defects was observed in the aBMSC-dECM scaffold group than in the BMS group according to gross observation, histological assessments, immunohistochemistry, and chemical assay. The glycosaminoglycan and DNA content, the distribution of proteoglycan, and the distribution and arrangement of type II and I collagen fibers in the repaired tissue in the aBMSC-dECM scaffold group at 12 weeks after surgery were similar to that surrounding normal hyaline cartilage. Implanting aBMSC-dECM scaffolds can enhance the therapeutic effect of BMS on articular cartilage repair, and this combination treatment is a potential method for successful articular cartilage repair.

Background: Enhanced recovery after surgery (ERAS) protocols were rapidly adopted in many surgeries such as fast-track arthroplasty. The study aimed to investigate the impact of ERAS protocols on the clinical effect of total knee arthroplasty (TKA) via the midvastus approach. Methods: A total of 69 patients who underwent primary unilateral TKA via the midvastus approach from October 2018 to June 2019 were enrolled and randomly divided into two groups: ERAS group and Control group. The ERAS protocols were adopted for the ERAS group and consisted of pure juice drinking 2 h before the surgery, optimization of the preoperative anesthesia plan, phased use of tourniquets, and the use of tranexamic acid as well as a drug cocktail. The operative time, first postoperative walking time, first straight leg elevation time, postoperative hospitalization time, visual analogue scale score (VAS score), Hospital for Special Surgery score (HSS score), conventional Knee Society score (KSS), and knee range of motion (ROM) were used to assess the clinical effects in the two groups. All the included patients were followed up for 12 months. Results: There were no significant differences in the basic demographic information and operation time between the ERAS and Control groups (P > 0.05). The first postoperative walking time (2.11 ± 0.11 h) and first postoperative straight leg elevation time (6.14 ± 1.73 h) in the ERAS group were significantly earlier than those in the Control group (P < 0.001) and the postoperative hospitalization time was significantly shorter (3.11 ± 0.32 days). The postoperative mean VAS scores in both groups were significantly reduced compared with those before surgery (P < 0.001). The VAS scores for the ERAS group were significantly lower than those for the Control group at 1, 2, and 7 days after surgery (P < 0.001). The mean HSS scores, KSS, and knee ROM were significantly increased in both the ERAS and Control groups at 1, 3, 6, and 12 months after surgery (P < 0.001). In addition, the HSS scores, KSS, and knee ROM in the ERAS group were significantly higher than those in the Control group at 1 month after surgery (P < 0.001). Conclusions: ERAS protocols improved the clinical effects of TKA via the midvastus approach, facilitating early out-of-bed activity and comfortable postoperative rehabilitation exercise, and further increasing patient satisfaction. Trial registration: ClinicalTrials.gov Identifier: NCT04873544.

We previously found that the combination of an autologous bone mesenchymal stem cell-derived extracellular matrix (aBMSC-dECM) scaffold with bone marrow stimulation could enhance hyaline cartilage regeneration. We suspected that chondrogenic differentiation could be induced by the aBMSC-dECM scaffold. This study aimed to investigate whether aBMSC-dECM scaffolds could promote chondrogenic differentiation without exogenous growth factors. BMSCs were seeded on aBMSC-dECM scaffolds and cultured in vitro with or without TGF-β3 (E+ or E- group). Atelocollagen scaffolds were used as controls (C+ or C- group). The chondrogenic differentiation was evaluated by histological, biochemical and real-time PCR assays. After 3 weeks, cartilage-like tissue with a homogeneous structure, a high cartilaginous matrix content (proteoglycan and type II collagen) and high expression levels of cartilage-associated genes (COL2A1, ACAN and SOX9) was observed in the E+, E- and C+ groups. In addition, BMSCs in each scaffold (E group or C group) were preconditioned with chondrogenic media in vitro for 1 week and then implanted in the backs of nude mice for 3 weeks. Three weeks later, cartilage matrix formation (proteoglycan and type II collagen) was achieved only in the E group, confirmed by safranin O staining and immunohistochemical staining for type II collagen. Taken together, these results indicate that aBMSC-dECM scaffolds could induce chondrogenic differentiation. Thus they could be successful candidate scaffolds for cartilage tissue engineering.