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Several methods using simple anteroposterior (AP) radiographs have been suggested for the measurement of anteversion of the cup component after total hip arthroplasty. Herein, we compared six widely used anteversion measurement methods using two different types of AP radiograph, the conventional pelvis AP and hip-centered AP radiographs, to identify the measurement method and the type of radiograph that would provide the highest accuracy and reliability. We developed two custom-made bi-planar anteversion measurement models for the validation test. The models were designed for pelvis AP and hip-centered AP radiographs, respectively. The radiographs were acquired using the inclination angles of both models, changing from 10° to 70° at 10° increments. For each inclination angle, anteversion was changed from 0° to 30° at 5° increments. The measurements were obtained independently by two orthopedic surgeons blinded from each other's measurements, using the methods of 1) Pradhan et al., 2) Lewinnek et al., 3) Widmer et al., 4) Liaw et al., 5) Hassan et al., and 6) Ackland et al. The measurements were repeated after 2 months. The accuracy, compared with that of the reference angle, and intra-observer and inter-observer reliabilities of each method were calculated. The highest accuracy was found when the method of Liaw et al. was used with hip-centered AP radiographs, which showed a difference of 1.37° ± 1.73 from the reference angle. Moreover, regardless of the type of radiograph, the methods by Pradhan et al., Lewinnek et al., and Liaw et al. showed excellent correlations with the reference anteversion. However, substantial differences were found when the methods by Widmer et al., Hassan et al., and Ackland et al. were used, regardless of the type of radiograph used. When anteversion was measured in an inclination between 30° and 50°, the method of Pradhan et al., when used with pelvis AP radiographs, showed the highest accuracy (1.23° ± 0.92°). We also found no significant difference in anteversions between the measurements made on pelvic and hip-centered AP radiographs. Both interobserver and intraobserver reliabilities were high for all the measurements tested. The methods by Pradhan et al., Liaw et al., and Lewinnek et al. may provide relatively accurate anteversion measurements with high reliability, regardless of the type of radiograph.

BACKGROUNDInadvertent intravascular injection of local anesthetics can lead to false-negative results following lumbar medial branch block (MBB) performed to diagnose facet joint origin pain. A previous study demonstrated that the type of approach method could affect the incidence of intravascular injections and technical ease of the procedure. OBJECTIVESThe primary objective of our study was to compare the incidence of inadvertent intravascular injection and technical ease of the MBB between anteroposterior (AP) and oblique (OB) views. STUDY DESIGNProspective randomized trial. SETTINGAn interventional pain management practice in South Korea. METHODSThe incidence of intravascular uptake of contrast medium was compared using AP and OB fluoroscopic views during lumbar MBB. Injection time, radiation dose, and patient discomfort during lumbar MBB were also compared. Risk factors associated with a longer procedure time and a higher radiation dose were analyzed. RESULTSThe incidence of intravascular injection was 22.5% (23/102) in the AP group and 17.6% (18/102) in the OB group (P = 0.382). A significantly longer injection time and a higher dose of radiation were required to complete 3 levels of MBB in the OB group than in the AP group (45.9 seconds vs 61.9 seconds, P = 0.001; 27.4 centigray [cGy]/cm2 vs 42.2 cGy/cm2, I = 0.004). The OB approach and left side injection were the risk factors associated with a longer total procedure time (odds ratio [OR] = 6.64, 95% CI, 1.99-22.17, P = 0.002; OR = 0.20, 95% CI, 0.06-0.67, P = 0.009, OB and AP, respectively). LIMITATIONSThe physician performing the MBB could recognize the AP or OB fluoroscopic view during procedure. CONCLUSIONThe overall incidence rate of intravascular injection during lumbar MBB showed nearly 20% in both approach methods groups. The OB approach and left side MBBs were associated with a longer total procedure time and a higher radiation dose.

In this study, we aimed to assess sprinting using a developed instrument encompassing an inertial measurement unit (IMU) in order to analyze athlete performance during the sprint, as well as to determine the number of steps, ground contact time, flight time, and step time using a high-speed camera as a reference. Furthermore, we correlated the acceleration components (XYZ) and acceleration ratio with the performance achieved in each split time obtained using photocells. Six athletes (four males and two females) ran 40 m with the IMU placed on their fifth lumbar vertebra. The accuracy was measured through the mean error (standard deviation), correlation (r), and comparison tests. The device could identify 88% to 98% of the number of steps. The GCT, flight time, and step time had mean error rates of 0.000 (0.012) s, 0.010 (0.011) s, and 0.009 (0.009) s when compared with the high-speed camera, respectively. The step time showed a correlation rate of r = 0.793 ( = 0.001) with no statistical differences, being the only parameter with high accuracy. Additionally, we showed probable symmetries, and through linear regression models identified that higher velocities result in the maximum anteroposterior acceleration, mainly over 0-40 m. Our device based on a Wi-Fi connection can determine the step time with accuracy and can show asymmetries, making it essential for coaches and medical teams. A new feature of this study was that the IMUs allowed us to understand that anteroposterior acceleration is associated with the best performance during the 40 m sprint test.

In this essay, we aim to explore in depth the new concept of the hypothalamus that was presented in the updated prosomeric model (Puelles et al., 2012b; Allen Developing Mouse Brain Atlas). Initial sections deal with the antecedents of prosomeric ideas represented by the extensive literature centered on the alternative columnar model of Herrick (1910), Kuhlenbeck (1973) and Swanson (1992, 2003); a detailed critique explores why the columnar model is not helpful in the search for causal developmental explanations. In contrast, the emerging prosomeric scenario visibly includes many possibilities to propose causal explanations of hypothalamic structure relative to both anteroposterior and dorsoventral patterning mechanisms, and insures the possibility to compare hypothalamic histogenesis with that of more caudal parts of the brain. Next the four major changes introduced in the organization of the hypothalamus on occasion of the updated model are presented, and our rationale for these changes is explored in detail. It is hoped that this example of morphological theoretical analysis may be useful for readers interested in brain models, or in understanding why models may need to change in the quest for higher consistency.

Purpose While anteroposterior instability of spinal segments is regarded as an important biomechanical aspect in the clinical evaluation of lumbar pathologies, the reliability of the available diagnostic tools is limited and an intraoperative method to quantify stability is lacking. The aim of this study was to develop and validate an instrument to measure the anteroposterior stability of a spinal segments in real-time. Methods Torsi of five fresh-frozen human cadavers were used for this study. After pedicle screw insertion, a specifically modified reposition tool composed with load and linear sensors was used to measure the segmental anteroposterior motion caused by 100 N anterior and posterior force during 5 loading cycles on either side of the instrumentation by two different operators. The spinal segments were then resected from the torsi and anteroposterior loading with ± 100 N was repeated in an advanced biomechanical spine testing setup as a reference measurement. The Inter-correlation coefficient (ICC) was used for validation of the “intraoperative” device. Results Inter-operator repeatability of the measurements showed an ICC of 0.93 ( p  < 0.0001) and the bilateral (left–right) comparison had an ICC of 0.73 ( p  < 0.0001). The ICC resulting from the comparison to the reference measurement was 0.82 ( p  < 0.0001) without offset correction, and 0.9 ( p  < 0.0001) with offset correction. The ICC converged at this value already after two of the five performed loading cycles. Conclusion An accurate and reliable measurement tool is developed and validated for real-time quantification of anteroposterior stability of spinal segments and serves as a basis for future intraoperative use.

Transforaminal epidural injection (TFEI) is a useful intervention for radicular leg pain. Compared to TFEI in lumbar level, S1 TFEI is reported to have higher incidence rates of intravascular injection as well as technical difficulties. The purpose of this study is to compare the incidence rates of intravascular injection and foramen passage time between anteroposterior (AP) and oblique (OB) approaches. Prospective randomized trial. An interventional pain management practice in South Korea. One hundred forty-seven patients receiving S1 TFEI for radicular leg pain were randomly assigned to one of 2 approach methods (AP view vs OB view). For S1 TFEI in the OB view group, lineup of the L5-S1 endplate was performed by adjusting the cephalad-caudad tilt. Then C-arm was rotated at an ipsilateral oblique angle, approximately 10° to 15°. After final confirmation of intravascular injection with real time fluoroscopy, the foramen passage time and amount of radiation exposure during S1 TFEI were measured. The incidence rate of intravascular injection in the AP view group was 24.2% (24/99), whereas that of intravascular injection in the OB view group was 10.1% (17/99, P = 0.008). The radiation dose required to pass the S1 foramen was significantly higher in the AP view group than in the OB view group (51.3 ± 27.2 cGy/cm2 vs 41.0 ± 17.0 cGy/cm2, P = 0.002). The foramen passage time during S1 TFEI was significantly higher in the AP view group than in the OB view group (103.5 ± 44.1 second vs 84.9 ± 21.0 second, P = 0.001). The failure rate of S1 TFEI was significantly higher in the AP view group than in the OB view group (13% vs 4%, P = 0.022). The physicians involved in the present study were not blinded to the type of approach method (AP view vs OB view) by fluoroscopy. Our study demonstrated reduced incidence rates of intravascular injection and reduced foramen passage time and radiation dosage with the use of OB view method during S1 TFEI.

Purpose The purpose of this study was to evaluate the changes in joint space width (JSW) over time after medial opening-wedge high tibial osteotomy (MOWHTO) and identify risk factors for deterioration of JSW using anteroposterior (AP) and Rosenberg views. Methods We retrospectively analyzed changes in JSW of 104 MOWHTO patients whose preoperative osteoarthritis (OA) grade was K-L grade 3 or less on AP and Rosenberg views. Serial changes in JSW were assessed from preoperatively to at least 3 years postoperatively. Patients were divided into two groups according to JSW change patterns on each of AP and Rosenberg views: non-deterioration group had either unchanged or increased JSW, and deterioration group had decreased JSW. Clinical outcomes were compared using Western Ontario and McMaster Universities OA Index (WOMAC) score between groups. Multivariate logistic regression analysis was performed to identify risk factors for deterioration of JSW. Results JSW on average for all patients increased 0.5 mm and 0.8 mm on AP and Rosenberg views, respectively ( p  < 0.05). Non-deterioration group showed significant improvement based on patient-reported outcomes (WOMAC) than deterioration group (all p  < 0.05). Undercorrection was an independent risk factor for failure to achieve maintained or increased JSW on both AP (OR 6.885, 95% CI 1.976–23.986, p  = 0.002) and Rosenberg (OR 12.756, 95% CI 2.952–55.129, p  = 0.001) views. Conclusion JSW increased gradually and continuously on standing AP and Rosenberg views until postoperative 3 years after MOWHTO. Deterioration of JSW following MOWHTO was closely related to the undercorrection and affected clinical outcomes. Level of evidence Level III, case control study.

Insufficient coverage causes hip joint instability and results in hip pain. Anterior hip coverage can be determined on both pelvic anteroposterior (AP) radiographs and false profile (FP) radiographs. Four parameters are commonly used to determine the anterior coverage on pelvic AP radiographs: the crossover index, crossover sign, anterior wall index (AWI), and rule of thirds. This study aims to clarify the relationship between these 4 parameters on AP radiographs and the anterior center edge angle (ACEA) on FP radiographs. In this study, 53 patients who underwent periacetabular osteotomy for hip dysplasia at our center between July 2020 and October 2020 were retrospectively reviewed. Four parameters on AP radiographs and the ACEA on FP radiographs before surgery and 6 months after surgery were measured and compared for each hip. Upon examining the 53 hips in this study, there was no correlation between either the crossover index and the ACEA (P = 0.66) or the crossover sign before surgery. The postoperative correlation between the crossover index and the ACEA was weak (r = 0.36, P = 0.007), and that between the crossover sign and the ACEA was moderate (r = 0.41, P = 0.003). There was a weak correlation between the AWI and ACEA both before (r = 0.288, P = 0.036) and after (r = 0.349, P = 0.011) the operation. Evaluation of the anterior coverage by the rule of thirds was also not consistent when determining the anterior coverage with the ACEA. Anterior coverage on AP radiographs is largely inconsistent with ACEA on FP radiographs, especially before the surgery. It is recommended to take FP radiographs routinely for determining anterior hip coverage.