Application of next-generation sequencing technology in the detection of pathogenic bacteria of the periprosthetic joint infection after arthroplasty

To investigate the application value of next-generation sequencing (NGS) technology in the detection of pathogenic bacteria in the periprosthetic joint infection after arthroplasty. Twenty-two cases of patients with joint infection after arthroplasty in our hospital from March 2020 to March 2021 were selected, with 11 cases of knee and 11 cases of hip, including 8 cases of male and 14 cases of female, and an average age of 63.55 ± 13.11 years old (range from 28 to 85). Microbiological culture results of synovial fluid and periprosthetic joint tissue and NGS results of periprosthetic joint tissue were collected. The detection rate of NGS and microbiological culture were calculated and statistically analysed by paired χ² test. Among the 22 patients with joint infection after arthroplasty, the positive rate of NGS was 90.91% (20/22), whereas the positive rate of bacterial culture was 50.00% (11/22). Paired chi-square test showed a statistically significant difference in the detection rate between the two groups (P = .0029). In the detection of pathogenic microorganism, NGS detected 12 kinds of bacteria, Staphylococcus aureus in 3 patients, Staphylococcus epidermidis in 5 cases, Streptococcus 1 case, Streptococcus dysgalactiae 1 case, Xanthomonas campestris 3 cases, Escherichia coli 2 cases, Bacillus cereus 2 cases, Klebsiella pneumoniae 1 case, Finegoldia magna 1 case, Corynebacterium klopensteriella in 1 case, Brucella 1 case, and Aspergillus flavus 1 case. Bacterial culture detected 6 kinds of bacteria, included 5 cases of Staphylococcus epidermis (including 3 cases of Methicillin-resistant coagulase-negative Staphylococcus, (MRSCoN)), 2 cases of Staphylococcus aureus (both Methicillin-resistant Staphylococcus aureus, (MRSA)), 1 case of Klebsiella pneumoniae, 1 case of Staphylococcus hominis (MRSCoN), 1 case of G⁺ bacillus, and 1 case of Brucella. Compared with bacterial culture, NGS technology has some advantages in the detection efficiency, detection rate, and comprehensiveness, which might be greater diagnostic value in the joint fluid of infection after arthroplasty.     

SIRT1 targeted by miR-211-5p regulated proliferation and apoptosis of Dex-treated growth plate chondrocytes via mediating SOX2

Dexamethasone (Dex) is reported to cause bone growth retardation in children, which is associated with the increased apoptosis and decreased proliferation of growth plate chondrocytes. Sirtuin 1 (SIRT1) plays an important role in chondrocyte function and homeostasis. Thus, we further explored the regulatory mechanism of SIRT1 in Dex-induced growth plate chondrocyte dysfunction. SIRT1 expression was detected in Dex-treated growth plate chondrocytes using RT-qPCR and western blot assay. The modulation of SIRT1 on SOX2 expression was evaluated. Besides, we identified that SIRT1 was targeted by miR-211-5p using TargetScan and RNA pull-down assay. A loss-of-function assay was performed to evaluate the effects of miR-211-5p on Dex-induced growth plate chondrocyte dysfunction in vitro and in vivo. We found that SIRT1 was downregulated in Dex-treated growth plate chondrocytes. The expression of SOX2 was upregulated by overexpression SIRT1. Meanwhile, downregulation of SOX2 weakened the positive function of SIRT1 overexpression on Dex-induced growth plate chondrocytes dysfunction. Subsequently, we confirmed that SIRT1 was targeted by miR-211-5p. MiR-211-5p inhibitor increased the expression levels of SIRT1 and SOX2, and restored the Dex-treated growth plate chondrocyte function. Animal assays further demonstrated that the effects of miR-211-5p on the growth plate chondrogenesis. In conclusion, our data suggest that SIRT1 exerts a protective effect on growth plate chondrocyte under Dex stimulation. MiR-211-5p/SIRT1/SOX2 axis regulates the process of Dex-inhibited growth plate chondrogenesis.     

Halving the usage of rigid-soled postoperative shoes does not affect outcomes in forefoot reconstruction surgery

BackgroundPostoperative shoes are commonly used after forefoot surgery. This study’s aim was to demonstrate that reducing rigid-soled shoe time to 3 weeks neither compromises functional outcomes nor does it produce complications.MethodsProspective cohort study: 6 weeks versus 3 weeks of rigid postoperative shoe (100 and 96 patients respectively), after forefoot surgery with stable osteotomies. Manchester-Oxford Foot Questionnaire (MOXFQ) and pain Visual Analog Scale (VAS) were studied preoperative and one year postoperative. Radiological angles were also assessed after removing the rigid shoe and at 6 months.ResultsThe MOXFQ index and pain VAS depicted similar results in each group (group A: 29.8 and 25.7; group B: 32.7 and 23.7) with no differences between them (p = .43 Vs. p = .58). Moreover, no differences were reported in their differential angles (HV differential-angle p = .44, IM differential-angle p = .18) or in their complication rate.ConclusionIn forefoot surgery with stable osteotomies, shortening the postoperative shoe time to 3 weeks, neither impairs clinical results nor the initial correction angle.     

Novel Claw-shaped Bone Plate in Complex Unstable Scapular Neck and Body Fractures: Comparison with Reconstruction Locking Plate

Objective

For complex and unstable scapular fractures requiring simultaneous fixation of the glenoid neck, the lateral margin of the body, and/or the scapular diaphysis, reconstruction locking plate is difficult to achieve satisfactory fixation. In order to optimize the fixation effect, the newly designed claw-shaped bone plate was designed for fixing such fractures. We also evaluate the clinical effects and follow-up at an average of 1 year after treatment in scapular internal fixation by using reconstruction locking plate and claw-shaped bone plate in complex unstable scapular body and glenoid neck fracture.

Methods

A retrospective study was conducted from 2018 to 2021, thirty-three patients (27 males and six females) who were defined unstable scapular fractures by Ada–Miller. Fifteen patients (52.86 ± 8.26 years) received claw-shaped bone plate and 18 cases (51.61 ± 11.31 years) received reconstruction locking plate with the intermuscular approach. The clinical effect was evaluated based on the operation time, intraoperative blood loss, surgical complications, clinical healing time and Constant–Murley score (CMS). The data analysis by Student t, Mann–Whitney U test and Pearson's chi squared test.

Results

Compared with reconstruction locking plate, the claw-shaped bone plate showed shorter operation time (102.73 ± 18.43 min vs. 156 ± 37.53, P < 0.0001), higher CMS (94.00 ± 4.07 vs. 89.88 ± 5.42, P = 0.02) and no differences between the two groups regarding intraoperative blood loss (208.00 ± 96.45 mL vs. 269.44 ± 120.21, P = 0.12) and clinical healing times (9.96 ± 1.52 vs. 10.05 ± 1.67, P = 0.87). Follow-up were conducted at first, third, 6 and 12 months after surgery. The operation was successful in all patients with no intraoperative complications.

Conclusions

For the treatment of complex and unstable scapular neck body fractures, the application of claw-shaped bone plate demonstrated short operation time, better stability of the fracture block, and higher CMS. In the intraoperative and postoperative follow-up showed better clinical results and rehabilitation effects.