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Background: Posterior cervical fusion (PCF) with lateral mass screws is a favorable treatment option to revise a symptomatic pseudarthrosis due to reliable rates of arthrodesis; however, this technique introduces elevated risk for wound infection and hospital readmission. A tissue-sparing PCF approach involving facet fixation instrumentation reduces the rates of postoperative complications while stabilizing the symptomatic level to achieve arthrodesis; however, these outcomes have been limited to small study cohorts from individual surgeons commonly with mixed indications for treatment. Materials and Methods: One hundred and fifty cases were identified from a retrospective chart review performed by seven surgeons across six sites in the United States. All cases involved PCF revision for a pseudarthrosis at one or more levels from C3 to C7 following anterior cervical discectomy and fusion (ACDF). PCF was performed using a tissue-sparing technique with facet instrumentation. Cases involving additional supplemental fixation such as lateral mass screws, rods, wires, or other hardware were excluded. Demographics, operative notes, postoperative complications, hospital readmission, and subsequent surgical interventions were summarized as an entire cohort and according to the following risk factors: age, sex, number of levels revised, body mass index (BMI), and history of nicotine use. Results: The average age of patients at the time of PCF revision was 55 ± 11 years and 63% were female. The average BMI was 29 ± 6 kg/m2 and 19% reported a history of nicotine use. Postoperative follow-up visits were available with a median of 68 days (interquartile range = 41-209 days) from revision PCF. There were 91 1-level, 49 2-level, 8 3-level, and 2 4±-level PCF revision cases. The mean operative duration was 52 ± 3 min with an estimated blood loss of 14 ± 1.5cc. Participants were discharged an average of 1 ± 0.05 days following surgery. Multilevel treatment resulted in longer procedure times (single = 45 min, multi = 59 min, P = 0.01) but did not impact estimated blood loss (P = 0.94). Total nights in the hospital increased by 0.2 nights with multilevel treatment (P = 0.01). Sex, age, nicotine history, and BMI had no effect on recorded perioperative outcomes. There was one instance of rehospitalization due to deep-vein thrombosis, one instance of persistent pseudarthrosis at the revised level treated with ACDF, and four instances of adjacent segment disease. In patients initially treated with multilevel ACDF, revisions occurred most commonly on the caudal level (48% of revised levels), followed by the cranial (43%), and least often in the middle level (9%). Conclusions: This chart review of perioperative and safety outcomes provides evidence in support of tissue-sparing PCF with facet instrumentation as a treatment for symptomatic pseudarthrosis after ACDF. The most common locations requiring revision were the caudal and cranial levels. Operative duration and estimated blood loss were favorable when compared to open alternatives. There were no instances of postoperative wound infection, and the majority of patients were discharged the day following surgery. [ABSTRACT FROM AUTHOR]

Inflammation driven by the NLRP3 inflammasome is coordinated through multiple signaling pathways and is regulated by subcellular organelles. Here, we tested the hypothesis that NLRP3 senses disrupted endosome trafficking to trigger inflammasome formation and inflammatory cytokine secretion. NLRP3-activating stimuli disrupted endosome trafficking and triggered localization of NLRP3 to vesicles positive for endolysosomal markers and for the inositol lipid PI4P. Chemical disruption of endosome trafficking sensitized macrophages to the NLRP3 activator imiquimod, driving enhanced inflammasome activation and cytokine secretion. Together, these data suggest that NLRP3 can sense disruptions in the trafficking of endosomal cargoes, which may explain in part the spatial activation of the NLRP3 inflammasome. These data highlight mechanisms that could be exploited in the therapeutic targeting of NLRP3. Inflammation-inducing traffic jams: The NLRP3 inflammasome assembles and is activated by diverse cellular stresses to produce proinflammatory cytokines. Lee et al. investigated whether the NLRP3 inflammasome was activated by disruptions in endosomal trafficking. By analyzing various cell types, including bone marrow-derived macrophages, the authors found that NLRP3-activating stimuli resulted in perturbations in endosomal trafficking and conversely, that chemical interference with endosomal trafficking potentiated NLRP3 activation, although it was insufficient to activate NLRP3 by itself. Activated NLRP3 was recruited to endolysosomal vesicles, where it colocalized with the lipid PI4P, which the authors speculated may be the additional stimulus required for NLRP3 activation. Thus, NLRP3 senses and is activated by cellular stress resulting from disordered endosomal trafficking. —WW [ABSTRACT FROM AUTHOR]

Paroxysmal hypnogenic dyskinesia is a rare clinical entity characterized by intermittent dystonia and choreoathetoid movements that begin exclusively during sleep, often with consciousness preserved once the patient is awakened during the episodes. They occur almost every night and are often misdiagnosed as sleeping disorders. Paroxysmal hypnogenic dyskinesia is currently known to be a form of frontal lobe epilepsy, but not in all cases. We present a 19-year-old male patient with paroxysmal hypnogenic dyskinesia who responded to antihistamines. This supports an alternative theory from 1977 (before the cases had been adequately described) that the disorder lies in dysregulation in the basal ganglia. This description now appears similar to acute dystonic reactions such as extrapyramidal symptoms from antipsychotic medications, which also respond to antihistamines. [ABSTRACT FROM AUTHOR]