Predictive factors for discharge destination after total hip arthroplasty.

BACKGROUND: This study aimed to investigate factors affecting discharge to an inpatient rehabilitation facility or home following total hip arthroplasty, using a clinical pathway in Japan. METHODS: Five hundred hips with osteoarthritis who underwent unilateral total hip arthroplasty at our institution, with no deviation from the pathway, were included in this retrospective study. The variables were examined by univariate analysis. Multivariate logistic regression analysis was used to identify the independent factors that influenced the discharge outcome. RESULTS: Four hundred and thirty-four hips were discharged home directly, and 66 were discharged to an inpatient rehabilitation facility. Patients discharged to an inpatient rehabilitation facility were significantly older, shorter, lighter, and more likely to live alone. Additionally, the preoperative clinical score was significantly lower in the inpatient rehabilitation facility Group for all items. Logistic regression analysis showed a significant association between being discharged to an inpatient rehabilitation facility and higher age [odds ratio 3.87, 95% confidence interval 2.03-7.38, P < 0.001], lower total score in the preoperative Japanese Orthopaedic Association hip score [odds ratio 2.42, 95% confidence interval 1.38-4.23, P = 0.002] and living alone [odds ratio 1.84, 95% confidence interval 1.01-3.35, P = 0.046]. CONCLUSIONS: In this study, age, the preoperative Japanese Orthopaedic Association hip score, and living arrangement impacted the discharge destination after THA.

Challenges and responses of elective orthopaedic surgery during the second wave of COVID-19.

BACKGROUND: Elective orthopaedic surgery has been severely curtailed because of coronavirus disease, 2019. There is scant scientific evidence to guide surgeons in assessing the protocols that must be implemented before resuming elective orthopaedic surgery safely after the second wave of the coronavirus disease, 2019. METHODS: A retrospective review of elective orthopaedic surgeries performed between May 15, 2020, and November 20, 2020, was conducted. A screening questionnaire was used, and reverse transcription-polymerase chain reaction and severe acute respiratory syndrome coronavirus-2 immunoglobulin G and IgM antibodies testing were assessed in all admitted patients. Screening and testing data for coronavirus disease was reviewed for all patients. RESULTS: Of 592 patients tested for severe acute respiratory syndrome coronavirus-2 during the study period, 21 (3.5%) tested positive. There were 2 patients (0.3%) with positive reverse transcription-polymerase chain reaction tests, 3 (0.5%) with positive IgG and IgM antibodies, 13 (2.2%) with positive IgG antibodies, and 10 (1.7%) with positive IgM antibodies. Among these 21 patients, 20 (95.2%) were asymptomatic. CONCLUSIONS: Our findings suggest that most elective orthopaedic surgery patients with severe acute respiratory syndrome coronavirus-2 are asymptomatic. In the second wave of coronavirus disease, 2019, universal testing of all patients should be strongly considered as an important measure to prevent clusters of in-hospital transmission of the disease.

Long-delayed expression of the immediate early gene Arc/Arg3.1 refines neuronal circuits to perpetuate fear memory.

Fear memories typically persist for long time periods, and persistent fear memories contribute to post-traumatic stress disorder. However, little is known about the cellular and synaptic mechanisms that perpetuate long-term memories. Here, we find that mouse hippocampal CA1 neurons exhibit biphasic Arc (also known as Arg3.1) elevations after fear experience and that the late Arc expression regulates the perpetuation of fear memoires. An early Arc increase returned to the baseline after 6 h, followed by a second Arc increase after 12 h in the same neuronal subpopulation; these elevations occurred via distinct mechanisms. Antisense-induced blockade of late Arc expression disrupted memory persistence but not formation. Moreover, prolonged fear memories were associated with the delayed, specific elimination of dendritic spines and the reactivation of neuronal ensembles formed during fear experience, both of which required late Arc expression. We propose that late Arc expression refines functional circuits in a delayed fashion to prolong fear memory.

Impacts of nicorandil on infarct myocardium in comparison with nitrate: assessed by cardiac magnetic resonance imaging.

In this pilot study, we compared the infarct and edema size in acute myocardial infarction (MI) patients treated by nicorandil with those treated by nitrate, using cardiac magnetic resonance (CMR) imaging. Fifty-two acute MI patients who underwent emergency percutaneous coronary intervention (PCI) were enrolled, and were assigned to receive nicorandil or nitrate at random just before reperfusion. For the assessment of infarct and edema areas, short-axis delayed enhancement (DE) and T2-weight (T2w) CMR images were acquired 6.1 ± 2.4 days after the onset of MI. A significant correlation was observed between the peak creatinine kinase (CK) level and the infarct size on DE CMR (r = 0.62, p < 0.05), as well as the edema size on T2w CMR (r = 0.70, p < 0.05) in patients treated by nicorandil (28 patients). A similar correlation was seen between the peak CK level and the infarct size on DE CMR (r = 0.84, p < 0.05), as well as the edema size on T2w CMR (r = 0.84, p < 0.05) in patients treated by nitrate (24 patients). The maximum CK level was significantly lower in patients treated by nicorandil rather than nitrate (1991 ± 1402, 2785 ± 2121 IU/L, respectively, p = 0.03). Both the edema size on T2w CMR and the infarct size on DE CMR were significantly smaller in patients treated by nicorandil rather than nitrate (17.7 ± 9.9, 21.9 ± 13.7 %; p = 0.03, 10.3 ± 6.0, 12.7 ± 6.9 %, p = 0.03, respectively). The presence and amount of microvascular obstruction were significantly smaller in patients treated by nicorandil rather than nitrate (39.2, 64.7 %; p = 0.03; 2.2 ± 1.3, 3.4 ± 1.5 cm(2); p = 0.02, respectively). Using CMR imaging, we demonstrated that the complementary use of intravenously and intracoronary administered nicorandil during PCI favorably acts more on the damaged myocardium after MI than nitrate. We need a further powered prospective study on the use of nicorandil.

Diagnostic usefulness of the oedema-infarct ratio to differentiate acute from chronic myocardial damage using magnetic resonance imaging.

OBJECTIVES: To differentiate acute from chronic damage to the myocardium in patients with myocardial infarction (MI) using DE and T2w MR. METHODS: Short-axis T2w and DE MR images were acquired twice after the onset of MI in 36 patients who successfully underwent emergency coronary revascularisation. The areas of infarct and oedema were measured. The oedema-infarct ratio (O/I) of the left ventricular area was calculated by dividing the oedema by the infarct area. RESULTS: The oedema size on T2w MR was significantly larger than the infarct size on DE MR in the acute phase. Both the oedema size on T2w MR and the infarct size on DE MR in the acute phase were significantly larger than those in the chronic phase. The O/I was significantly greater in the acute phase compared with that in the chronic phase (P < 0.05). An analysis of relative cumulative frequency distributions revealed an O/I of 1.4 as a cut-off value for differentiating acute from chronic myocardial damage with the sensitivity, specificity, and accuracy of 85.1%, 82.7% and 83.9%, respectively. CONCLUSION: The oedema-infarct ratio may be a useful index in differentiating acute from chronic myocardial damage in patients with MI. KEY POINTS: MR can differentiate reversible from irreversible myocardial damage after myocardial infarction. MR is a useful modality to noninvasively differentiate the infarct stages. The O/I is an important index to decide therapeutic strategies.

Treatment strategy for surgical site infection post posterior lumbar interbody fusion: A retrospective study.

Introduction: Posterior lumbar interbody fusion (PLIF) has been widely used to treat various degenerative spinal diseases. However, surgical site infection (SSI) post-PLIF is often difficult to cure. This study aimed to clarify the difference in clinical course due to the causative organism and develop a treatment strategy for SSI post-PLIF. Methods: Between January 2011 and March 2019, 581 PLIF surgeries were performed at our hospital. Deep SSI occurred in 14 patients who were followed up for more than 2 years. Causative bacterial species were diagnosed by preoperative puncture and/or intraoperative drainage or by tissue culture in 13 patients and by intradiscal puncture in one patient who underwent conservative treatment. Of the 13 patients who underwent surgeries for infection, 10 had Propionibacterium acnes (Group A; n = 4) or coagulase-negative Staphylococcus (CNS) (Group B; n = 6) as the causative bacterial species. Groups A and B were retrospectively compared in terms of age, sex, number of segments, presence of diabetes mellitus, operation time, blood loss, C-reactive protein on hematological examination, the elapsed time to diagnosis (ETD), the presence of clinical findings such as heat, redness, swelling, and discharge from the wound and healing time. Results: All infections were eradicated with surgery except in one patient whose causative bacteria was CNS; cages were finally removed in 11 patients. There was a significant difference (P = 0.0105) in the ETD and clinical findings (P = 0.0476) between Groups A and B. Posterior one-stage simultaneous revision (POSSR) was performed in nine patients, of whom eight were cured and one required additional surgery. Conclusions: The ETD and clinical findings were significantly different in SSI cases caused by different bacteria, which will be useful in predicting the causative bacteria in future cases. For the treatment of deep SSI post-PLIF, POSSR was effective.

Hemophagocytic syndrome in a patient with rheumatoid arthritis.

A 76-year-old man with rheumatoid arthritis, who had been treated with oral prednisolone and methotrexate, presented with high fever and generalized fatigability. Laboratory data demonstrated marked pancytopenia, which we first regarded as a side effect of methotrexate, and leucovorin was administered with granulocyte-colony stimulating factor and transfusions. Because no recovery was recognized, however, bone marrow aspiration was performed, by which hemophagocytic syndrome was diagnosed. After corticosteroid pulse therapy was initiated, the patient's symptoms were rapidly attenuated and laboratory data rapidly normalized.

[A case of perforating rectal ulcer with retroperitoneal emphysema treated with conservative medical management].

A 75-year-old woman complaining of sudden lower abdominal pain, fever, and bloody stool was admitted to the hospital. Abdominal CT scan showed retroperitoneal emphysema ranging from the retrorectal space to the posterior region of the kidney, and a stool-like shadow around the rectum. It suggested rectal ulcer and conservative management was started since the general condition was not critical and abdominal pain was localized. Colonoscopy revealed a solitary ulcerative lesion on the posterior wall of rectosigmoid colon, which was considered to be perforating origin. We report a case of perforating rectal ulcer with retroperitoneal emphysema successfully treated conservatively.

Total hip arthroplasty via an anterolateral supine approach for obese patients increases the risk of greater trochanteric fracture.

PURPOSE: The aim of this study was to evaluate the outcomes and early complications of obese patients who underwent total hip arthroplasty for osteoarthritis via an anterolateral approach in the supine position (ALS-THA) and compare these outcome with of a matched control group of non-obese patients. PATIENTS AND METHODS: Thirty-one hips in 28 patients with obesity (BMI ≧ 30 kg/m2) were included in this study. As a control group, 31 hips of 31 patients with a normal weight (BMI between 20 and 25 kg/m2) were matched based on age, sex, and laterality. Clinical evaluations using the Merle d'Aubigne and Postel hip score, radiological evaluations and perioperative complications were compared in two groups. RESULTS: There were no significant differences between the groups in the operative time, period of hospitalization, clinical hip score, or cup positioning, although the position of the cup tended to deviate from the optimal safe zone in the obese compared with non-obese group (32.3 and 16.1%, respectively). There was no infection, dislocation, nerve palsy, or life-threatening event in either group. The rate of avulsion fractures of the greater trochanter in the obese group was 3 times higher compared to that in the non-obese group. CONCLUSIONS: As the clinical outcome of ALS-THA for the obese group is not inferior to that for the non-obese group, obesity is not considered to be a contraindication for ALS-THA. However, obesity increases the risk of intraoperative greater trochanteric fracture. Thus, surgeons should be particularly careful when manipulating the femur in this class of patients, who should be informed of this risk.

Multistage chemical etching for high-precision frequency adjustment in ultrahigh-frequency fundamental quartz resonators.

Chemical etching to precisely adjust and to make uniform the thicknesses of vibrating areas of multiple resonators in a single wafer was applied to inverted-mesa quartz resonators exciting an ultrahigh-frequency fundamental thickness vibration. The process consisted of five stages, combining high-rate etching for high productivity and low-rate etching for high-precision adjustment. By using this process, the resonance frequencies of 41 resonators in the single wafer were adjusted to 620 +/- 1.5 MHz, which corresponds to vibrating area thicknesses of 2.2 microm +/- 6 nm. In the temperature-frequency characteristics of these resonators in the single wafer, the difference between the maximum first-order temperature coefficient and the minimum first-order temperature coefficient was equivalent to a cut angle change of two arcminutes. In addition, vibrating areas with an arithmetic mean surface roughness of 0.17 nm on the concave side were produced by this multistage etching.