Objective：The aim of this study is to obtain information for setting a common shear rate for the viscosimetry of thickened liquids.Materials & Methods：The panelists (healthcare professionals involved in dysphagia) drank five maltose syrups, and organized them in the order of viscosity based on their pharyngeal sense. Then, they drank three thickened liquids, i.e., 1.4% and 0.95% xanthan gum (XAN) solutions, and 1.4% guar gum (GUA) solution, and aligned them with the maltose syrups. We carried out the test twice using different concentrations of maltose syrups and obtained 126 answers. Results：Of all panelists, 77% could correctly arrange the five maltose syrups in the order of viscosity. The answers of the panelists who could serialize the five maltose syrups and the two XAN solutions were as follows. There were few answers that corresponded to shear rate of less than 11 sec^-1 for each of the thickened liquids. Meanwhile, most frequently answers corresponded to the shear rates of 61-140 sec^-1, 80-240 sec^-1, 210-620 sec^-1 for 1.4% XAN, 0.95% XAN, and 1.4 GUA solutions, respectively. Conclusion：The common shear rate for the viscosimetry of thickened liquids was not equivalent to the shear rate of 3 sec^-1 historically adopted in Japan；it was at least 50 sec^-1 according to the results of the sensory evaluation.

Methods: The study included data from 100 patients who underwent ASD surgery between 2012 and 2020. Fifteen of these patients presented with RFs. Patient demographics, clinical outcomes, and radiographic parameters were evaluated in each group. Results: RFs were significantly more frequent in patients with a medical history of total hip arthroplasty (THA; p=0.01) or severe obesity (p=0.04). However, no significant differences in clinical outcomes, preoperative or postoperative measurements, or changes were found between pre- and postoperative radiographic parameters within the groups. Both pre- (p=0.01) and postoperative (p=0.02) anterior disc heights were significantly greater in the RF group than in the non-RF group. In the RF group, the postoperative lordotic angles of the lumbosacral junction significantly decreased compared with preoperative angles (p=0.02). Multiple logistic regression analysis demonstrated that a THA history (odds ratio, 34.2), severe obesity (odds ratio, 14.0), and preoperative anterior disc height (odds ratio, 1.2) were significant risk factors for RFs. Conclusions In this study, the greatest risk factors for postoperative lumbosacral RF after ASD surgery were THA history, severe obesity, and postoperative anterior disc height of ≥10. For patients at higher risk, the use of multirods is considered necessary.

Methods: Fifty-six patients (13 males and 43 females) with an average age of 80.2±9.2 years admitted to the hospital for FFS between 2006 and 2021 were analyzed retrospectively. The following patient data were collected using medical records: pain regions, a history of trauma, initial diagnoses, and rates of fracture detection using radiography, computed tomography (CT), and magnetic resonance imaging (MRI). Results: Forty-one patients presented with low back and/or buttock pain, nine presented with groin pain, and 17 presented with thigh or leg pain. There was no history of trauma in 18 patients (32%). At the initial visit, 27 patients (48%) were diagnosed with sacral or pelvic fragility fractures. In contrast, 29 patients (52%) were initially misdiagnosed with lumbar spine disease (23 patients), hip joint diseases (three patients), and buttock bruises (three patients). Fracture detection rates for FFS were 2% using radiography, 71% using CT, and 93% using MRI. FFS was diagnosed definitively using an MRI with a coronal short tau inversion recovery (STIR) sequence. Conclusions Some patients with FFS have leg pain with no history of trauma and are initially misdiagnosed as having lumbar spine disease, hip joint disease, or simple bruises. When these clinical symptoms are reported, we recommend considering FFS as one of the differential diagnoses and performing lumbar or pelvic MRIs, particularly coronal STIR images, to rule out FFS.

Methods: Cases of 50 patients with ASD who underwent long spinal fusion (>9 levels) with S2AI screws were retrospectively reviewed. Loosening of S2AI screws and S1 pedicle screws and bone fusion at the level of L5–S1 at 2 years after surgery were investigated using computed tomography. In addition, risk factors for loosening of S2AI screws were determined in patients with ASD. Results: At 2 years after surgery, 33 cases (66%) of S2AI screw loosening and six cases (12%) of S1 pedicle screw loosening were observed. In 40 of 47 cases (85%), bone fusion at L5–S1 was found. Pseudarthrosis at L5–S1 was not significantly associated with S2AI screw loosening (19.3% vs. 6.3%, p=0.23), but significantly higher in patients with S1 screw loosening (83.3% vs. 4.9%, p<0.001). On multivariate logistic regression analyses, high upper instrumented vertebra (UIV) level (T5 or above) (odds ratio [OR], 4.4; 95% confidence interval [CI], 1.0–18.6; p=0.045) and obesity (OR, 11.4; 95% CI, 1.2–107.2; p=0.033) were independent risk factors for S2AI screw loosening. Conclusions High UIV level (T5 or above) and obesity were independent risk factors for S2AI screw loosening in patients with lumbosacral fixation in surgery for ASD. The incidence of lumbosacral fusion is associated with S1 screw loosening, but not S2AI screw loosening.