The Prevalence and Risk Factors for S2 Alar-Iliac Screw Loosening with a Minimum 2-Year Follow-up
ASIAN SPINE JOURNAL
Authors: Nakashima, Hiroaki; Kanemura, Tokumi; Satake, Kotaro; Ito, Kenyu; Ishikawa, Yoshimoto; Ouchida, Jun; Segi, Naoki; Yamaguchi, Hidetoshi; Imagama, Shiro
Abstract
Study Design A retrospective cohort study. Purpose: The purpose of this study was to investigate the prevalence and risk factors for S2 alar-iliac (SAL) screw loosening following lumbosacral fixation, with a minimum 2-year follow-up. Overview Literature: Although SAI screws allow surgeons to perform lumbosacral fixation with a low profile and enhanced biomechanical strength, screw loosening following surgery can occur in some cases. However, few studies have investigated the prevalence and risk factors for SAI screw loosening. Methods; This retrospective study included 35 patients (mean age, 72.8 +/- 8.0 years; male, 10; female, 251 who underwent lumbosacral fixation using SAI screws with at least 2 years of follow-up. SAI screw loosening and L5-S bony fusion were assessed using computed tomography. The period for which the screws appeared loose and the risk factors for SAI screw loosening were investigated 2 years after surgery. Results: A total of 7D SAI screws and 70 S1 pedicle screws were inserted. Loosening was observed D.5, 1, and 2 years after surgery in 17 (24.3%1, 35 (50.0%), and 35(50.0%) SAI screws, respectively. Bony fusion rate at L5-S was significantly lower in patients with SAI screw loosening than in those without screw loosening (65.0% vs. 93.3%, p=0.048). The score for CAI screw contact with the iliac cortical hone and the bony fusion rate at L5-S were significantly lower in the loosening group than in the non -loosening group (1.8 +/- 0.5 vs. 2.2 +/- 0.3,p<0.001, respectively). Postoperative pelvic incidence lumbar lorclosis was significantly higher in the loosening group than in the non -loosening group (7.9 degrees +/- 15.4 degrees vs. 0.5 degrees +/- 8.7 degrees,p=0.02, respectively). Conclusicms: SAI screw loosening is closely correlated with pseudoarthrosis at L5-S. Appropriate ion and opt a bar lordosis restoration are important to prevent postoperative complications related to SAI screws.
Effects of medium chain fatty acids as a mitigation or prevention strategy against porcine epidemic diarrhea virus in swine feed
JOURNAL OF ANIMAL SCIENCE
Authors: Lerner, Annie B.; Cochrane, Roger A.; Gebhardt, Jordan T.; Dritz, Steve S.; Jones, Cassandra K.; DeRouchey, Joel M.; Tokach, Michael D.; Goodband, Robert D.; Bai, Jianfa; Porter, Elizabeth; Anderson, Joe; Gauger, Phillip C.; Magstadt, Drew R.; Zhang, Jianqiang; Bass, Benjamin; Karnezos, Theodore; de Rodas, Brenda; Woodworth, Jason C.
Abstract
Feed has been shown to be a vector for viral transmission. Four experiments were conducted to: 1) determine if medium chain fatty acids (MCFA) are effective mitigants when applied to feed both pre- and post-porcine epidemic diarrhea virus (PEDV) inoculation measured by quantitative reverse transcription polymerase chain reaction (qRT-PCR), 2) evaluate varying levels and combinations of MCFA measured by qRT-PCR, and 3) evaluate selected treatments in bioassay to determine infectivity. In exp. 1, treatments were arranged in a 2 x 2 + 1 factorial with main effects of treatment (0.3% commercial formaldehyde [CF] product, Sal CURB [Kemin Industries, Inc.; Des Moines, IA], or 1% MCFA blend (Blend) of 1:1:1 C6:C8:C10 [PMI, Arden Hills, MN]) and timing of application (pre- or post-inoculation with PEDV) plus a positive control (PC; feed inoculated with PEDV and no treatment). All combinations of treatment and timing decreased detectable PEDV compared with the PC (P < 0.05). Pre-inoculation treatment elicited decreased magnitude of PEDV detection (cycle threshold value) compared with post-inoculation (P = 0.009). Magnitude of PEDV detection was decreased for CF compared with Blend (P < 0.0001). In exp. 2, pre-inoculation treatments consisted of: 1) PC, 2) 0.3% CF, 3 to 5) 0.125% to 0.33% C6:0, 6 to 8) 0.125% to 0.33% C8:0, 9 to 11) 0.125% to 0.33% C10:0, and 12 to 15) 0.125% to 0.66% C5:0. Treating feed with 0.33% C8:0 resulted in decreased (P < 0.05) PEDV detection compared with all other treatments. Increasing concentration of each individual MCFA decreased PEDV detectability (P < 0.042). In exp. 3, pre-inoculation treatments consisted of: 1) PC, 2) 0.3% CF, 3 to 7) 0.25% to 1% Blend, 8 to 10) 0.125% to 0.33% C6:0 + C8:0, 11 to 13) 0.125% to 0.33% C6:0 + C10:0, and 14 to 16) 0.125% to 0.33% C8:0 + C10:0. Treating feed with CF, 0.5% Blend, 0.75% Blend, 1% Blend, all levels of C6:0+C8:0, 0.25% C6:0 + 0.25% C10:0, 0.33% C6:0 + 0.33% C10:0, 0.25% C8:0 + 0.25% C10:0, or 0.33% C8:0 + 0.33% C10:0 elicited decreased detection of PEDV compared with PC (P < 0.05). Increasing concentration of each MCFA combination decreased PEDV detectability (linear, P < 0.012). In exp. 4, feed was treated pre-inoculation with: 1) no treatment (PC), 2) 0.3% CF, 3) 0.5% Blend, or 4) 0.3% C8:0 and analyzed via qRT-PCR and bioassay. Adding 0.5% Blend or 0.3% C8:0 resulted in decreased PEDV compared with PC and only PC resulted in a positive bioassay. Therefore, MCFA can decrease detection of PEDV in feed. Further, inclusion of lower levels of MCFA than previously evaluated are effective against PEDV.