Possible Risk Factors for Severe Complications Occurring after Primary Total Knee Arthroplasty / 中国医学科学杂志(英文版)

Objective Total knee arthroplasty is one of the most common orthopedic surgeries. Readmission due to severe complications after total knee arthroplasty is a grave concern to surgeons. In this study, we evaluated the risk factors for severe complications after primary total knee arthroplasty. Methods We retrospectively collected clinical data of 2,974 patients who underwent primary total knee arthroplasty from July 2013 to June 2019 in our hospital. Postoperative complication ≥ grade Ⅲ was defined as severe complication according to Clavien-Dindo classification system. Binary logistic regression was used to identify the predictive risk factors for severe complications. Results The complication rate after primary total knee arthroplasty was 6.8% and severe complication rate was 2.5%. Male (OR = 2.178, 95%CI: 1.324-3.585, P= 0.002), individuals above 75 years old (OR = 1.936, 95%CI: 1.155-3.244, P= 0.012), arrhythmia (OR = 2.913, 95%CI: 1.350-6.285, P= 0.006) and cerebrovascular disease (OR = 2.804, 95%CI: 1.432-5.489, P= 0.003) were predictive risk factors for severe complications after primary total knee arthroplasty. Conclusion Advanced age, male, arrhythmia, and cerebrovascular disease might be patients-related risk factors for postoperative severe complications after primary total knee arthroplasty. Special attention should be paid to patients with risk factors.

PSD95 gene specific siRNAs attenuate neuropathic pain through modulating neuron sensibility and postsynaptic CaMKIIα phosphorylation / 中国医学科学杂志(英文版)

<p><b>OBJECTIVE</b>To observe the effects of PSD95 gene specific siRNAs on neuropathic pain relief, neuron viability, and postsynaptic calcium/calmodulin-dependent protein kinase IIα (CaMKIIα) phosphorylation in vitro and in vivo.</p><p><b>METHODS</b>Gene-specific siRNAs of rat PSD95 were synthesized chemically for transfection. Adult male Sprague-Dawley (SD) rats were randomly divided into 3 groups: naïve group (n=6), sham group (n=6), and sciatic nerve chronic constriction injury (CCI) group (n=24). The CCI group was further divided into 4 groups (n=6 in each group), which were pretreated with normal saline, transfection vehicle, negative control siRNAs, and PSD95 gene specific siRNAs respectively. All the subgroups received corresponding agents intrathecally for 3 days, started one day before the CCI of sciatic nerve. Both mechanical allodynia and thermal hyperalgesia were measured on post-operative day 3 and 7. PSD95 gene silenced NG108-15 cells were further stimulated by glutamate, with the cell viability and the expression/phosphorylation of CaMKIIα measured by MTT cell proliferation assay and Western blot, respectively.</p><p><b>RESULTS</b>The siRNAs decreased PSD95 mRNA level significantly both in vivo and in vitro. Neuropathic pain rats pretreated with PSD95 gene specific siRNAs exhibited significant elevation in the mechanical withdrawal threshold and paw withdrawal thermal latency, without affecting the baseline nociception. PSD95 gene silencing enhanced neuronal tolerance against the glutamate excitotoxicity, meanwhile the phosphorylation of CaMKIIα Thr286 was attenuated.</p><p><b>CONCLUSION</b>Pre-emptive administration of PSD95 gene specific siRNAs may attenuate the central sensitization CaMKIIα-related signaling cascades, leading to the relief of neuropathic pain.</p>