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Background: The quadrant method is widely used to determine the femoral footprint center (FFC) on radiographs or computed tomography (CT) and can also describe the tibial footprint center (TFC). However, its application on three-dimensional (3D) magnetic resonance imaging (MRI) has been limited. This study aims to describe the ACL footprint center position on 3D MRI of healthy knees using the quadrant method. Methods: Proton density (PD) sequence 3D MRI was conducted on 45 intact knees, aged 18 to 45 years. The centers of the ACL footprints were determined, and 2D simulated radiographic images were generated from the 3D MRI data. The quadrant method was then applied to calculate the positions of the footprint centers. Results: The FFC was located at 31.6% in the deep–shallow (DS) direction and 31.3% in the high–low (HL) direction. The TFC was positioned at 45.1% in the mediolateral (ML) direction and 39.9% in the anteroposterior (AP) direction. Conclusions: The ACL footprint centers identified in this study were positioned similarly to previous studies, with the exception of the TFC in the ML direction, which was found to be more medial. This approach has the potential to enhance preoperative planning and intra-operative navigation in ACL reconstruction surgeries. [ABSTRACT FROM AUTHOR]

Abstract Purpose This prospective study aimed to compare the postoperative evaluation of the quadrant method measuring four points and Bernard method in femoral tunnel position evaluation on 3-Dimensional (3D) reconstructed computed tomography (CT) following the arthroscopic single-bundle anterior cruciate ligament (ACL) reconstruction. Methods Thirty-eight patients with ACL tears that were reconstructed using single-bundle ACL reconstruction between May 2021 and March 2023 were included in this study. Postoperative 3D CT images were obtained after the operation. The femoral tunnel position was measured by use of the quadrant method measuring four points and Bernard method. Results Average mean position of the femoral tunnel insertion center on the 3D CT image was at 26.16 ± 6.27% in the x-coordinate and at 24.36 ± 5.52% in the y-coordinate according to the Bernard method. Meanwhile, the position of the femoral insertion of the ACL measured by the quadrant method measuring four points was 24.2% ± 6.86% in the x-coordinate and 21.16% ± 5.14% in the y-coordinate. Conclusions Both the quadrant method measuring four points and Bernard method were effective in femoral tunnel position evaluation on 3D reconstructed CT. Application of the quadrant method measuring four points on 3D CT showed the advantage that measurement can be taken regardless of the shape of the bone tunnel.

Purpose: The purpose of this study was to examine the intra- and interobserver variability of an app-based analysis of the femoral tunnel position using the quadrant method in primary anterior cruciate ligament reconstruction. Materials and methods: Between 12/2020 und 12/2021 50 patients who underwent primary anterior cruciate ligament reconstruction were included in this retrospective study. Intraoperative strictly lateral fluoroscopic images of the knee with marked femoral tunnel were analyzed by four observers using the quadrant method. For retest reliability analysis, measurements were repeated once by 2 observers after 4 weeks. Results: The femoral tunnel position of all included patients averaged 27.86% in the depth relation and 15.61% in the height relation. Statistical analysis showed an almost perfect intra- and interobserver reliability in the depth and height relation. The ICC was 0.92 in the depth relation and 0.84 in the height relation. The Pearson's correlation coefficient in the depth and height relation of observer 1 (0.94/0.81) was only slightly different from the Pearson's correlation coefficient of observer 2 (0.92/0.85). The app-based tunnel analysis took on average 59 ± 16 s per measurement. Conclusion: The femoral tunnel analysis with the app-based quadrant method has an almost perfect intra- and interobserver reliability. By smartphone camera, a fast and highly accurate, if necessary also intraoperative, control of the tunnel position can be performed. Level of evidence: Level 3—diagnostic retrospective cohort study. [ABSTRACT FROM AUTHOR]

Positioning of the femoral tunnel during anterior cruciate ligament (ACL) reconstruction is the most crucial factor for successful procedure. Owing to the inter-individual variability in the intra-articular anatomy, it can be challenging to obtain precise tunnel placement and ensure consistent results. Currently, the three-dimensional (3D) reconstruction of computed tomography (CT) scans is considered the best method for determining whether femoral tunnels are positioned correctly. Postoperative 3D-CT feedback can improve the accuracy of femoral tunnel placement. Precise tunnel formation obtained through feedback has a positive effect on graft maturation, graft failure, and clinical outcomes after surgery. However, even if femoral tunnel placement on 3D CT is appropriate, we should recognize that acute graft bending negatively affects surgical results. This review aimed to discuss the implementation of 3D-CT evaluation for predicting postoperative outcomes following ACL re-construction. Reviewing research that has performed 3D CT evaluations after ACL reconstruction can provide clinically significant evidence of the formation of ideal tunnels following anatomic ACL reconstruction. [ABSTRACT FROM AUTHOR]

Positioning of the femoral tunnel during anterior cruciate ligament (ACL) reconstruction is the most crucial factor for successful procedure. Owing to the inter-individual variability in the intra-articular anatomy, it can be challenging to obtain precise tunnel placement and ensure consistent results. Currently, the three-dimensional (3D) reconstruction of computed tomography (CT) scans is considered the best method for determining whether femoral tunnels are positioned correctly. Postoperative 3D-CT feedback can improve the accuracy of femoral tunnel placement. Precise tunnel formation obtained through feedback has a positive effect on graft maturation, graft failure, and clinical outcomes after surgery. However, even if femoral tunnel placement on 3D CT is appropriate, we should recognize that acute graft bending negatively affects surgical results. This review aimed to discuss the implementation of 3D-CT evaluation for predicting postoperative outcomes following ACL re-construction. Reviewing research that has performed 3D CT evaluations after ACL reconstruction can provide clinically significant evidence of the formation of ideal tunnels following anatomic ACL reconstruction.

Objective To develop a novel screw positioning method to improve the treatment of unstable thoracolumbar fractures. Methods A total of 72 patients with unstable thoracolumbar fractures who were treated with anterior screw–rod interfixation from January 2011 to October 2015 were included in this clinical study. Those patients included 48 male and 24 female patients with an average age of 45.10 years (range, 26–63 years). Patients were randomly divided into two groups: an observation group (n = 36) and a control group (n = 36). The quadrant positioning method was used for screw insertion in the observation group during the operation, while the traditional screw positioning method was used in the control group. The quadrant positioning method targeted four quadrants, including the superior anterior (SA), superior posterior (SP), inferior anterior (IA) and inferior posterior (IP) quadrants, while for the traditional screw positioning, four screws were inserted into the vertebral bodies above and below the excision. Patients were followed up for approximately 40 months to record recovery. Clinical and radiological records, local angle and fractured vertebra body height, clinical outcomes, complications, neurological improvement, and fusion rate were recorded and compared between the two groups. Results The quadrant positioning method was successfully used for anterior screw insertion. The quadrant center in the lateral view of the vertebral body was well marked, and screws were easily located on the scheduled quadrant. Blood loss (BL), hospital stay (HS), and operation time (OP) in the observation group were 749.40 ± 379.90 mL, 17.10 ± 4.10 days, and 167.40 ± 44.70 min, respectively. While those parameters in the control group were 1198.40 ± 339.27 mL, 23.22 ± 3.77 days, and 221.47 ± 32.15 min, respectively. The average operation time and hospital stay time were significantly shorter, and blood loss was significantly less in the observation group than in the control group (P

Background: Anatomical placement of an ACL graft is critical to the clinical outcome of an ACL reconstruction. The purpose of the study was to compare the conventional technique of drilling a femoral tunnel from a medial portal while viewing it from a lateral portal versus viewing it from a high anteromedial portal and drilling it from a low medial portal. We hypothesized that the high anteromedial portal possibly provides an end-on view of the tunnel and would lead to a more favourable tunnel position. Materials and Methods: Sixty patients underwent arthroscopic single-bundle ACL reconstruction with a soft tissue graft. All patients had the same surgeon and same surgical technique (except viewing portal). Each patient underwent a 3D-CT 1-week post-op. We classified the patients into two groups (technique A and B) of 30 each. Postoperative tunnel position in each patient was visualized on CT scan with 3D reconstruction by the quadrant method described by Bernard et al. The distance of the centre of the femoral tunnel from the superior and posterior border of the Bernard frame was obtained in each patient of the two groups and mean value in each group was obtained and compared by Student 't' test at 5% level of significance. The position of the femoral tunnels was also studied in reference to the lateral intercondylar ridge and classified into type I (well placed), type II (moderately malpositioned) and type III (grossly malpositioned) Results: The mean distances in technique A from the posterior and superior border of the lateral femoral condyle was 35.8 ± 8.2 and 35.2 ± 6.7, and in technique B was 38.1 ± 8.6 and 35.8 ± 9.4. The two groups did not differ significantly (P > 0.05) in femoral tunnel position as visualized on 3D-CT scan postoperatively. 53.3% patients had well-placed tunnels (type I) overall with 56.67% of technique A and 50% of technique B in this group. None of the tunnels were grossly malpositioned. Conclusions: The absence of any statistically significant difference between the groups suggests that a high anterolateral portal close to the patellar tendon gives an almost complete view of the lateral aspect of the notch, if not end on. Both techniques produced a majority of well placed (type I) tunnels [ABSTRACT FROM AUTHOR]

Aim To evaluate tunnel positioning on radiographs in singlebundle (SB) and double-bundle (DB) anterior cruciate ligament (ACL) reconstruction, to evaluate if measurement is accurate and reproducible. Methods Radiographs of 30 SB and 30 DB ACL reconstruction were reviewed by two examiners who measured tunnel positioning with the quadrant method on the femur (a=depth, b=height) and the Amis and Jakob method on the tibia. Intra- and inter-observer reliability were evaluated with intra-class correlation coefficient (ICC). Results A radiographic analysis was completed in all patients in a SB-group and in 27 in a DB-group (p>0.05). Intra-observer reliability was almost perfect on femoral (ICC: a=0.85, b=0.83) and tibial (ICC=0.87) side in the SB-group. In the DB-group, it was almost perfect for tibial anteromedial (AM) and posterolateral (PL) bundles (ICC: AM=0.84, PL=0.81) and for femoral PL bundle (ICC: a=0.83, b=0.82), and substantial for femoral AM bundle (ICC: a=0.78, b=0.74). Inter-observer reliability was almost perfect on tibial (ICC=0.81) and femoral (ICC: a=0.81, b=0.87) side in the SB-group, and substantial on tibial (ICC: AM=0.71, PL=0.77) and femoral (ICC: AM a=0.73, b=0.78; PL a=0.74, b=0.76) side in the DB-group. Standard deviation (SD) was low (±9%) with respect to the centre of tunnel(s). Conclusion The quadrant method and the Amis and Jakob method are accurate and reproducible measurement methods. Also, as SD was low, an outside-in approach with a front-entry guide, which is free-hand positioned, can be postulated as a reliable method to locate the femoral tunnel in SB reconstruction and the AM bundle in DB reconstruction. [ABSTRACT FROM AUTHOR]

Purpose: To investigate how the femoral sagittal cutting plane affects evaluation of the bone tunnel position after anterior cruciate ligament (ACL) reconstruction using the quadrant method in three-dimensional computed tomography (CT) imaging. Methods: Thirty patients who underwent primary anatomic double-bundle ACL reconstruction and CT 2 weeks after surgery were enrolled. Three sagittal cutting planes with respect to the condylar axis were created using the CT images: at the top of the intercondylar notch (C-plane), 5% medial (M-plane), and 5% lateral (L-plane). The center of the bone tunnel position regarding depth and height of the anteromedial (AMB) and posterolateral bundle (PLB) were quantitatively evaluated using the quadrant method on the three different planes. Results: The mean depths of AMB and PLB were 27.4 ± 4.4% and 39.7 ± 5.1%, 27.0 ± 4.2% and 37.6 ± 4.9%, and 27.4 ± 4.5% and 38.5 ± 6.0%, at the M, C and L planes, respectively. The mean heights of AMB and PLB were 30.8 ± 6.3% and 56.2 ± 5.6%, 30.4 ± 6.2% and 56.6 ± 5.6%, and 25.4 ± 7.0% and 52.9 ± 6.9% at the M, C, and L planes, respectively. Both AMB and PLB bone tunnels were evaluated as higher positions in the L-plane than the C-plane (p < 0.01, p = 0.02, respectively) and M-plane (p < 0.01, p = 0.04, respectively), but there were no significant differences between the C-plane and M-plane (n.s.). There was no significant difference in the anteroposterior direction for all planes. Conclusion: In evaluations of the bone tunnel position with the quadrant method using three-dimensional CT, the bone tunnel position depends on the femoral sagittal cutting plane. A consistent evaluation method should be used when evaluating the bone tunnel position after ACL reconstruction to enable correct evaluation clinically. Level of evidence: Case–control study, Level III. [ABSTRACT FROM AUTHOR]

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New decentralization regim implemented since 1 January 2001. Decentralization try to increase the improvement of public services. Based on the statictic data, Java recorded a major contributor to national GDP growth with many challenge on poverty and inequality. Using the share and growth analysis as well as quadrant method, this research tries to provide mapping economy potency and regional independency in Java. From the share analysis, still dominated by provincial government, which the biggest is DKI Jakarta Province. From the smallest share, Gunung Kidul Regency is the weakest independency. Based on growth analysis, Jepara Regency, Tangerang, Ngawi, Mojokerto and Tangsel City became the largest. From the quadrant method, 15 regions are in quadrant I, about 19 other areas are in quadrant II and 37 areas are in quadrant III. And largest part of the Java could classify in quadrant IV. According on these findings, central government must producing several policy to speed up the development regions particularly on all regional in quadrant IV.

Purpose: The quadrant method is used to evaluate the bone tunnel position with the grid based on the Blumensaat's line in anterior cruciate ligament (ACL) reconstruction. This study aimed to clarify the influence of variation in the Blumensaat's line on the accuracy of the quadrant method measurements.Methods: A retrospective review of the radiological records of patients aged 18-30 years who underwent computed tomography (CT) scanning of the knee joint was conducted. The Blumensaat's line inclination angle (BIA), along with the most posterior point of the posterior condyle (point P) position using the quadrant method and morphology of the Blumensaat's line were measured on true lateral transparent three-dimensional CT images of the distal femoral condyle in 147 patients. Statistical analysis was conducted to determine associations among these measurements.Results: BIA was 37.5° (standard deviation 4.2°; range 27°-48°). The point P position was significantly correlated with BIA in the high/low (R2 = 0.590, P < 0.0001) and deep/shallow (R2 = 0.461, P < 0.0001) directions. The morphology of the Blumensaat's line was straight in 35 knees (23.8%); whereas, the remaining 112 knees (76.2%) were not straight but had some hill on the Blumensaat's line. No significant difference among the morphological variation of the Blumensaat's line was observed in BIA and the point P position.Conclusion: There was a strong correlation between BIA and the point P measured using the quadrant method, suggesting the influence of the Blumensaat's line on the accuracy of the quadrant method measurements in ACL reconstruction. As for the clinical relevance, surgeons should be careful in application of the quadrant method for ACL reconstruction, because the variation of the Blumensaat's line inclination influences the accuracy of this method. [ABSTRACT FROM AUTHOR]

Abstract Background Commercially available flexible reamer and curved guide systems allow a certain degree of control over intra-articular tunnel orientation, therefore allows a wide range of intra-osseous femoral tunnel orientations, contrary to the femoral tunneling technique using a straight guide pin, which are determined by knee flexion angle. We sought to find the clinical relevance of intra-osseous femoral tunnel orientations in the respect of tunnel length. To evaluate the relationship between the tunnel axis angle in three orthogonal planes and tunnel length in the anteromedial (AM) and posterolateral (PL) femoral tunnels in patients who underwent anatomic double-bundle anterior cruciate ligament reconstruction (DB-ACLR) using the transportal (TP) technique with a 42o curved guide. Methods A total of 40 patients who underwent primary DB-ACLR with the TP technique using a curved guide were evaluated retrospectively. The tunnel axis angle in three orthogonal planes were evaluated on a three-dimensional surface model constructed using an axial computed tomography scan obtained after reconstruction. Then, correlations with tunnel length were analyzed. Results In the AM tunnel, tunnel axis angles in the coronal (β = 0.0252, p = 0.022) and sagittal (β = 0.0168, p = 0.029) plane showed significant correlations with tunnel length, while the axial plane did not (p = 0.493) (adjusted R2 = 0.801). In the PL tunnel, only tunnel axis angles in the axial plane (β = 0.0262, p = 0.008) showed a significant relationship with tunnel length (adjusted R2 = 0.700). Conclusion Drilling at a higher angle in the coronal and sagittal planes in AM tunnels and at a higher angle in the axial plane in PL tunnels decreases the incidence of short femoral tunnels.

Purpose: This study aimed to determine the influence of femoral tunnel orientation on long-term clinical outcome and osteoarthritis in patients undergoing ACL reconstruction and to test the reliability of the implemented radiographic measurement methods. It was hypothesized that a more horizontal femoral tunnel would correlate with superior clinical outcome.Methods: A cohort of 193 patients who underwent non-anatomic ACL reconstruction was examined. In this specific study, non-anatomic is defined by the surgeons' pursuit of optimal isometry, not to emulate the native ACL anatomy. At follow-up, the Lachman test, the KT-1000, the pivot-shift test, the one-leg-hop test and the IKDC-2000 were evaluated. Osteoarthritis was evaluated radiographically. Posteroanterior and lateral radiographs were used to determine the position of the femoral tunnel in the coronal and sagittal planes and the angle of the tunnel in the coronal plane. A method for determining femoral rotation on the lateral radiographs was developed and its reliability was evaluated. The femoral tunnel orientation was analyzed to examine its influence on clinical outcome and osteoarthritis.Results: A total of 101 patients were analyzed at a mean of 16.4 (± 1.3) years postoperatively. The reliability of the measurement methods was regarded as good to excellent (ICC 0.57-0.97). The mean coronal femoral tunnel angle was 9.6° (± 9.4°). The coronal femoral tunnel was positioned at a mean of 43% (± 3.5%) of the distance measured from lateral to medial. The mean sagittal femoral tunnel position, measured using the quadrant method, was 40% (± 6.4%) from posterior to anterior. No significant associations were found between tunnel orientation and the clinical outcome variables.Conclusions: The orientation of the femoral tunnel did not predict the long-term subjective outcome, functional outcome or the development of osteoarthritis in patients undergoing non-anatomic ACL reconstruction. The method for determining femoral rotation on lateral radiographs was found to be reliable.Level Of Evidence: Retrospective cohort study, level of evidence IV. [ABSTRACT FROM AUTHOR]

Objective: To develop a novel screw positioning method to improve the treatment of unstable thoracolumbar fractures. Methods: A total of 72 patients with unstable thoracolumbar fractures who were treated with anterior screw–rod interfixation from January 2011 to October 2015 were included in this clinical study. Those patients included 48 male and 24 female patients with an average age of 45.10 years (range, 26–63 years). Patients were randomly divided into two groups: an observation group (n = 36) and a control group (n = 36). The quadrant positioning method was used for screw insertion in the observation group during the operation, while the traditional screw positioning method was used in the control group. The quadrant positioning method targeted four quadrants, including the superior anterior (SA), superior posterior (SP), inferior anterior (IA) and inferior posterior (IP) quadrants, while for the traditional screw positioning, four screws were inserted into the vertebral bodies above and below the excision. Patients were followed up for approximately 40 months to record recovery. Clinical and radiological records, local angle and fractured vertebra body height, clinical outcomes, complications, neurological improvement, and fusion rate were recorded and compared between the two groups. Results: The quadrant positioning method was successfully used for anterior screw insertion. The quadrant center in the lateral view of the vertebral body was well marked, and screws were easily located on the scheduled quadrant. Blood loss (BL), hospital stay (HS), and operation time (OP) in the observation group were 749.40 ± 379.90 mL, 17.10 ± 4.10 days, and 167.40 ± 44.70 min, respectively. While those parameters in the control group were 1198.40 ± 339.27 mL, 23.22 ± 3.77 days, and 221.47 ± 32.15 min, respectively. The average operation time and hospital stay time were significantly shorter, and blood loss was significantly less in the observation group than in the control group (P < 0.05). Local angle and vertebral body height were markedly improved and 1–2 grade improvement was achieved in patients with neurological deficits in both groups. Both groups of patients achieved bony fusion during follow‐up. No incision infection or internal fixation failure was observed in the two groups, and complications including cerebrospinal fluid and chylous leakage and hemothorax were resolved. Conclusions: The quadrant positioning method can shorten operation time, reduce blood loss, and accelerate postoperative recovery. The technique provides an effective method for screw insertion for double screw–rod instrumentation fixation in the treatment of thoracolumbar fracture via the anterior approach. [ABSTRACT FROM AUTHOR]

Abstract A new statistical method, the quadrant method, was used to aid in identifying different conditions affecting the relationship between columnar aerosol optical depth (τ ext) and surface concentrations of particulate matter (<2.5 μg m−3 in aerodynamic diameter, PM 2.5). The main goal of this study was to identify air pollution sources and atmospheric processes affecting gradients of atmospheric pollutants observed at two valley sites (∼1370 m) and a high elevation site (2515 m) located in and adjacent to Reno, Nevada, USA. The two valley sites were used to investigate the horizontal gradient of pollutants associated with mobile sources from high volume highways. Results indicated statistically significant differences in concentrations of criteria air pollutants between the two valley sites, located 0.03 km and >1 km from major highways. Vertical gradients were impacted by air pollution sources, including local and long-range transport, and atmospheric boundary layer stability. During periods when τ ext and surface PM 2.5 concentrations were associated (i.e. both increase), emissions from wildfires and local pollutants in a well-mixed boundary layer dominated the relationship. During periods of no association, stable boundary layer conditions and pollution aloft created vertical heterogeneity of PM 2.5 concentrations. Results showed that the quadrant method, developed for hourly data, can be used with 24 h PM 2.5 and gaseous data and that it is a useful tool for identifying air pollution sources and atmospheric physics driving pollution gradients. Highlights • Statistical analysis of atmospheric sources and physics affecting pollution gradients. • Quadrant method applied to understand relationships between τ ext and surface PM 2.5 • Horizontal pollution gradients in the valley were influenced by highways. • Stability, transport aloft, and wildfires drove vertical heterogeneity of pollution. • Quadrant method was successfully applied to 24 h data. [ABSTRACT FROM AUTHOR]

Indonesia has been running a decentralized reform era since 1 January 2001. The goal of decentralization is to accelerate the realization of prosperity through the improvement of public services. Fiscal decentralization then became the main benchmark of the successful creation of indicators of regional autonomy in addressing various problems in the regions, especially inequality and poverty. According to government data, Sumatra recorded a major contributor to national GDP growth while facing poverty, inequality constraints and also the largest mining sector. By using the shared and growth analysis and quadrant method, this research tries to provide policy-making recommendations based on the characteristics of the regions in Sumatra. Based on shared analysis, the biggest region is Bengkalis Regency, Riau Province, Siak Regency, Rokan Hilir Regency, and Musi Banyuasin Regency. For the smallest region, it consists of West Nias Regency, North Nias, Toba Samosir, Gunung Sitoli and South Nias. From the growth analysis, it was found that Mesuji Regency, Southeast Aceh Padang Lawas Utara, Kota Padang Panjang and West Nias Regency have the highest growth in Indonesia. From the quadrant method, 20 regions are in quadrant I, about 54 other areas are in quadrant II, and 35 areas are in quadrant III. The largest part of the regional classification in the region of Sumatra is in quadrant IV. Based on these findings, fiscal policy in the future should be prioritized to develop on regional eradication in quadrant IV in terms of Transfer to Region.

Abstract The present study aims at investigating turbulence characteristics in high flow velocity areas like those suitable for marine energy application. The Reynolds number, based on the rugosity height and mean flow velocity, is rather high: R e = 2. 5 × 1 0 7. For that purpose, experiments are carried out in a flume tank with R e as high as achievable in Froude similitude (in the tank: R e = 2. 5 × 1 0 5 and F r = 0. 23). Obstacles are canonical wall-mounted elements chosen to be representative of averaged bathymetric variations: a cube and a cube followed by an inclined floor. First, the wake topology past a canonical wall-mounted cube is illustrated from PIV measurements. Results show a flow behaviour already observed in the literature but for different upstream conditions (R e and turbulence intensity). Second, the impact of the addition of an inclined floor is studied. It is shown that the inclination causes a squeezing of the cube wake that strongly impacts the shape and intensity of the shear layer (up to 10% more intense with the inclined floor). To fully grasp the turbulence organization in the wake for both test cases, an analysis using both complementary Proper Orthogonal Decomposition and quadrant method is performed. POD acts as a turbulent noise filter and quadrant method decomposes turbulent events. Results show the predominance of ejection (Q2) and sweep (Q4) events in the flow Reynolds shear stress. Q2 events are more energetic although Q4 events prevail. It is observed that the inclined floor causes a persistence of Q2 and Q4 events higher into the water column, more than the impulsion given by the floor altitude variations. The rise of the cube wake due to the inclined floor is thus illustrated using Q4 predominance area. Highlights • Tests are carried out on a wall-mounted cube with and without an inclined floor representative of seabed elements, in Froude similitude with high Reynolds number. • PIV measurements are performed in horizontal and vertical measurement planes and spatial analyses are performed. • POD filter and quadrant analyses show the rise of coherent energetic structures. [ABSTRACT FROM AUTHOR]

Purpose: The quadrant method was described by Bernard et al. and it has been widely used for postoperative evaluation of anterior cruciate ligament (ACL) reconstruction. The purpose of this research is to further develop the quadrant method measuring four points, which we named four-point quadrant method, and to compare with the quadrant method.Methods: Three-dimensional computed tomography (3D-CT) analyses were performed in 25 patients who underwent double-bundle ACL reconstruction using the outside-in technique. The four points in this study's quadrant method were defined as point1-highest, point2-deepest, point3-lowest, and point4-shallowest, in femoral tunnel position. Value of depth and height in each point was measured. Antero-medial (AM) tunnel is (depth1, height2) and postero-lateral (PL) tunnel is (depth3, height4) in this four-point quadrant method. The 3D-CT images were evaluated independently by 2 orthopaedic surgeons. A second measurement was performed by both observers after a 4-week interval. Intra- and inter-observer reliability was calculated by means of intra-class correlation coefficient (ICC). Also, the accuracy of the method was evaluated against the quadrant method.Results: Intra-observer reliability was almost perfect for both AM and PL tunnel (ICC > 0.81). Inter-observer reliability of AM tunnel was substantial (ICC > 0.61) and that of PL tunnel was almost perfect (ICC > 0.81). The AM tunnel position was 0.13% deep, 0.58% high and PL tunnel position was 0.01% shallow, 0.13% low compared to quadrant method.Conclusions: The four-point quadrant method was found to have high intra- and inter-observer reliability and accuracy. This method can evaluate the tunnel position regardless of the shape and morphology of the bone tunnel aperture for use of comparison and can provide measurement that can be compared with various reconstruction methods. The four-point quadrant method of this study is considered to have clinical relevance in that it is a detailed and accurate tool for evaluating femoral tunnel position after ACL reconstruction.Level Of Evidence: Case series, Level IV. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the feedback from post-operative three-dimensional computed tomography (3D-CT) on femoral tunnel placement in the learning process, to obtain an anatomic anterior cruciate ligament (ACL) reconstruction.Methods: A series of 60 consecutive patients undergoing primary ACL reconstruction using autologous hamstrings single-bundle outside-in technique were prospectively included in the study. ACL reconstructions were performed by the same trainee-surgeon during his learning phase of anatomic ACL femoral tunnel placement. A CT scan with dedicated tunnel study was performed in all patients within 48 h after surgery. The data obtained from the CT scan were processed into a three-dimensional surface model, and a true medial view of the lateral femoral condyle was used for the femoral tunnel placement analysis. Two independent examiners analysed the tunnel placements. The centre of femoral tunnel was measured using a quadrant method as described by Bernard and Hertel. The coordinates measured were compared with anatomic coordinates values described in the literature [deep-to-shallow distance (X-axis) 28.5%; high-to-low distance (Y-axis) 35.2%]. Tunnel placement was evaluated in terms of accuracy and precision. After each ACL reconstruction, results were shown to the surgeon to receive an instant feedback in order to achieve accurate correction and improve tunnel placement for the next surgery. Complications and arthroscopic time were also recorded.Results: Results were divided into three consecutive series (1, 2, 3) of 20 patients each. A trend to placing femoral tunnel slightly shallow in deep-to-shallow distance and slightly high in high-to-low distance was observed in the first and the second series. A progressive improvement in tunnel position was recorded from the first to second series and from the second to the third series. Both accuracy (+52.4%) and precision (+55.7%) increased from the first to the third series (p < 0.001). Arthroscopic time decreased from a mean of 105 min in the first series to 57 min in the third series (p < 0.001). After 50 ACL reconstructions, a satisfactory anatomic femoral tunnel was reached.Conclusion: Feedback from post-operative 3D-CT is effective in the learning process to improve accuracy and precision of femoral tunnel placement in order to obtain anatomic ACL reconstruction and helps to reduce also arthroscopic time and learning curve. For clinical relevance, trainee-surgeons should use feedback from post-operative 3DCT to learn anatomic ACL femoral tunnel placement and apply it appropriately.Level Of Evidence: Consecutive case series, Level IV. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study was to evaluate the difference in the center position of the ACL footprint based on grid placement using the quadrant method according to the morphological variations of the Blumensaat's line.Methods: Fifty-nine non-paired human cadaver knees were used. The ACL was cut in the middle, and the femoral bone was cut at the most proximal point of the femoral notch, and the digital images were evaluated using Image J software. The femoral ACL footprint was periphery outlined and the center position was automatically measured. Following Iriuchishima's classification, the morphology of the Blumensaat's line was classified into straight, small hill, and large hill types. From the images, grid quadrants were placed as: Grid (1) without consideration of hill existence and not including the chondral lesion. Grid (2) without consideration of hill existence and including the chondral lesion. Grid (3) with consideration of hill existence and not including the chondral lesion. Grid (4) with consideration of hill existence and including the chondral lesion.Results: The straight type consisted of 19 knees, the small hill type 13 knees, and the large hill type 27 knees. Depending on the quadrant grid placement, significant center position difference was observed both in the shallow-deep, and high-low direction. When hill existence was considered, the center position of the ACL was significantly changed to a high position.Conclusion: The center position of the ACL footprint exhibited significant differences according to Blumensaat's line morphology. For clinical relevance, when ACL surgery is performed in knees with small or large hill type variations, surgeons should pay close attention to femoral tunnel evaluation and placement, especially when using the quadrant method. [ABSTRACT FROM AUTHOR]

Fiscal decentralization reform era started since January 1st, 2001, with the implications of changes from centralized to highly decentralized. Unfortunately, it led to a greater dependence on the Local Government to Central Government through the Intergovernmental Transfers, especially on General Allocation Fund (DAU) and also a few on the Specific Allocation Fund (DAK) and Revenue Sharing (DBH). Based on that problem, this research aims to describe regional performances since 2008 until 2014, using several indicators and quadrant method approaches. In accordance with the calculation of the ratio of local independence, the majority of regions are in the category of less independent. While using dependency ratio, the majority of regions are in the group of very large dependency and a dependency. From the results of quadrant analysis methods, most regions are in quadrant III, which means to have a high dependence on government assistance. As a policy recommendation, the government needs to evaluate the improvement of the fiscal decentralization in Indonesia.

Purpose: Femoral tunnel positioning is an important factor in anatomical ACL reconstructions. To improve accuracy, lateral radiographic support can be used to determine the correct tunnel location, applying the quadrant method. Piefer et al. (Arthroscopy 28:872-881, 2012) combined various outcomes of eight studies applying this method to one guideline. The studies included in that guideline used various insertion margins, imaging techniques and measurement methods to determine the position of the ACL centres. The question we addressed is whether condensing data from various methods into one guideline, results in a more accurate guideline than the results of one study.Methods: The accuracy of the Piefer's guideline was determined and compared to a guideline developed by Luites et al. (2000). For both guidelines, we quantified the mean absolute differences in positions of the actual anatomical centres of the ACL, AM and PL measured on the lateral radiographs of twelve femora with the quadrant method and the positions according to the guidelines.Results: The accuracy of Piefer's guidelines was 2.4 mm (ACL), 2.7 mm (AM) and 4.6 mm (PL), resulting in positions significantly different from the actual anatomical centres. Applying Luites' guidelines for ACL and PL resulted in positions not significantly different from the actual centres. The accuracies were 1.6 mm (ACL) and 2.2 mm (PL and AM), which were significantly different from Piefer for the PL centres, and therefore more accurate.Conclusions: Condensing the outcomes of multiple studies using various insertion margins, imaging techniques and measurement methods, results in inaccurate guidelines for femoral ACL tunnel positioning at the lateral view.Clinical Relevance: An accurate femoral tunnel positioning for anatomical ACL reconstruction is a key issue. The results of this study demonstrate that averaging of various radiographic guidelines for anatomical femoral ACL tunnel placement in daily practice, can result in inaccurate tunnel positions.Level Of Evidence: Diagnostic study, Level 1. [ABSTRACT FROM AUTHOR]

Anterior cruciate ligament (ACL) injury causes knee joint instability, and effects on sports performance. Therefore, ACL reconstruction is essential to keep their high performance. It is well known that the outcome of ACL reconstruction is strongly related to the placement and orientation of the bone tunnel. Therefore, optimization of tunnel drilling technique is an important factor to obtain satisfactory surgical results. Current procedure relies on arthroscopic evaluation and there is a risk of damaging arteries and ligaments during surgery. The damages may reduce the accuracy and reproducibility of ACL reconstruction. As a postoperative evaluation method, a quadrant method has been used to evaluate the placement and orientation of the bone tunnel in X-ray radiography. This study proposes a computer-aided surgical planning system for evaluating ACL insertion site and orientation using magnetic resonance (MR) images. We first introduce MR image based the quadrant method to determine the ACL insertion site for preoperative patients. It also evaluates the 3-D spatial relationship between the planning femoral drilling hole and arteries around the femoral condyle. This system has been applied to ACL injured patients, it may increase the accuracy and reproducibility of ACL bone tunnel, and it can evaluate a risk of damaging the surrounding arteries and ligaments. [ABSTRACT FROM AUTHOR]

Purpose: A modified quadrant method was developed for description of femoral tunnel aperture positions on the sagittal plane after double-bundle anterior cruciate ligament (ACL) reconstruction, which can be measured by using two-view radiographs. The purpose of the study is to provide a new measurement method and to evaluate the reproducibility and accuracy of the method. Methods: Forty-one patients who had undergone a double-bundle ACL reconstruction were investigated. Two-view plain radiographs, a 45-degree-flexion posterior-anterior standing (Rosenberg) and a lateral view, were taken at 1 year postoperatively, and the femoral tunnel positions were measured. Intra- and inter-observer reproducibility was calculated by means of intra-class correlation coefficient (ICC). Also, the accuracy of the method was evaluated by comparing the measurement from three-dimensional computed tomography (3D-CT). Results: Intra-observer reproducibility was excellent (ICC > 0.9). Inter-observer reproducibility of antero-medial (AM) tunnel position was almost perfect (ICC > 0.8) and that of postero-lateral (PL) tunnel was substantial (ICC > 0.7). The accuracy of the method was assessed by comparing the measurement from 3D-CT and was found to be almost perfect (ICC > 0.8). With the modified quadrant method, the average height of AM and PL tunnels were 17.8 and 44.4 %, respectively, and the depth of AM and PL tunnels were 25.5 and 36.7 %, respectively. Conclusions: A modified quadrant method was found to have acceptable reproducibility and accuracy. The method is useful for describing the femoral tunnel aperture positions in ACL reconstruction because of its easiness and simplicity. By using this method, it is possible to analyse the femoral tunnel position even in the cases without CT analysis. Level of evidence: IV. [ABSTRACT FROM AUTHOR]

Fretting fatigue commonly exists at the junction of contacting bodies that are subjected to oscillating force. Meanwhile, the presence of fretting will affect the fatigue lifetime dramatically, especially when the material is heterogeneous as cracks initiate at defects such as inclusions, micro-voids and micro-cracks. Fretting fatigue is a multi-axial non-proportional loading problem, in which most components and assemblies undergo asynchronous loads. Thus, investigating the influence of phase angle (Φ) in heterogeneous materials is quite meaningful. In this study, different locations of micro-voids in three different loading phase angles are taken into consideration. The critical plane approach and quadrant method are adopted to predict the crack initiation lifetime and crack orientation. It is found that the existence of micro-voids significantly affects the damage parameter, when Φ equals 180°, and plays a relatively small effect when Φ equals 90°. In addition, the crack initiation lifetime varies with the location of micro-voids since the location of micro-voids has different effects on the damage parameters. [ABSTRACT FROM AUTHOR]

The particle entrainment ability of coherent flow structures is investigated by comparing statistical properties of momentum flux u′ w′ and of turbulent mass fluxes c′ u′ and c′ w′ in suspension, open-channel flow under capacity charge conditions. The quadrant repartitions of these quantities as a function of the corresponding threshold levels are estimated. A cumulant discard probability density distribution is used to calculate the theoretical quadrant dynamics. Good agreement between the third-order model and the experimental results is found for all investigated quantities in the wall and intermediate flow regions. In the free surface domain, the increase of intermittency of the momentum and mass transport processes leads to small discrepancies between the model and the experimental results. The quadrant distributions of the horizontal and vertical turbulent mass fluxes are dominated by the same two quadrants as the momentum flux u′ w′. Ascendent mass flux events are found to correlate with ejections over the entire water depth. A dynamical equilibrium between the shear stress production term and the turbulent energy dissipation term is found in the intermediate flow region where the value of the normalized vertical flux of turbulent kinetic energy in suspension flow corresponds well with the one observed in clear water flows. This points toward a universality of the normalized vertical flux of turbulent kinetic in highly turbulent boundary layers. The suspended particle transport capacity of coherent structures is directly quantified from the estimation of the conditionally sampled terms of the particle diffusion equation. Coherent structures are found to play a dominant role in the mass transport mechanism under highly turbulent flow conditions in open-channel flows. [ABSTRACT FROM AUTHOR]

Background: Anatomical placement of an ACL graft is critical to the clinical outcome of an ACL reconstruction. The purpose of the study was to compare the conventional technique of drilling a femoral tunnel from a medial portal while viewing it from a lateral portal versus viewing it from a high anteromedial portal and drilling it from a low medial portal. We hypothesized that the high anteromedial portal possibly provides an end-on view of the tunnel and would lead to a more favourable tunnel position., Materials and Methods: Sixty patients underwent arthroscopic single-bundle ACL reconstruction with a soft tissue graft. All patients had the same surgeon and same surgical technique (except viewing portal). Each patient underwent a 3D-CT 1-week post-op. We classified the patients into two groups (technique A and B) of 30 each. Postoperative tunnel position in each patient was visualized on CT scan with 3D reconstruction by the quadrant method described by Bernard et al. The distance of the centre of the femoral tunnel from the superior and posterior border of the Bernard frame was obtained in each patient of the two groups and mean value in each group was obtained and compared by Student ' t ' test at 5% level of significance. The position of the femoral tunnels was also studied in reference to the lateral intercondylar ridge and classified into type I (well placed), type II (moderately malpositioned) and type III (grossly malpositioned)., Results: The mean distances in technique A from the posterior and superior border of the lateral femoral condyle was 35.8 ± 8.2 and 35.2 ± 6.7, and in technique B was 38.1 ± 8.6 and 35.8 ± 9.4. The two groups did not differ significantly ( P  > 0.05) in femoral tunnel position as visualized on 3D-CT scan postoperatively. 53.3% patients had well-placed tunnels (type I) overall with 56.67% of technique A and 50% of technique B in this group. None of the tunnels were grossly malpositioned., Conclusions: The absence of any statistically significant difference between the groups suggests that a high anterolateral portal close to the patellar tendon gives an almost complete view of the lateral aspect of the notch, if not end on. Both techniques produced a majority of well placed (type I) tunnels., Competing Interests: Conflict of InterestThe authors declare that they have no conflict of interest., (© Indian Orthopaedics Association 2020.)

Background: Commercially available flexible reamer and curved guide systems allow a certain degree of control over intra-articular tunnel orientation, therefore allows a wide range of intra-osseous femoral tunnel orientations, contrary to the femoral tunneling technique using a straight guide pin, which are determined by knee flexion angle. We sought to find the clinical relevance of intra-osseous femoral tunnel orientations in the respect of tunnel length. To evaluate the relationship between the tunnel axis angle in three orthogonal planes and tunnel length in the anteromedial (AM) and posterolateral (PL) femoral tunnels in patients who underwent anatomic double-bundle anterior cruciate ligament reconstruction (DB-ACLR) using the transportal (TP) technique with a 42 o curved guide., Methods: A total of 40 patients who underwent primary DB-ACLR with the TP technique using a curved guide were evaluated retrospectively. The tunnel axis angle in three orthogonal planes were evaluated on a three-dimensional surface model constructed using an axial computed tomography scan obtained after reconstruction. Then, correlations with tunnel length were analyzed., Results: In the AM tunnel, tunnel axis angles in the coronal (β = 0.0252, p = 0.022) and sagittal (β = 0.0168, p = 0.029) plane showed significant correlations with tunnel length, while the axial plane did not (p = 0.493) (adjusted R 2  = 0.801). In the PL tunnel, only tunnel axis angles in the axial plane (β = 0.0262, p = 0.008) showed a significant relationship with tunnel length (adjusted R 2  = 0.700)., Conclusion: Drilling at a higher angle in the coronal and sagittal planes in AM tunnels and at a higher angle in the axial plane in PL tunnels decreases the incidence of short femoral tunnels.

Purpose: the aim of this study was to compare clinical results and location of the femoral tunnel with transtibial (TT) and outside-in (OI) techniques in anterior cruciate ligament (ACL) reconstruction using in vivo 3D CT analysis., Methods: we prospectively followed up 40 ACL reconstructions in which femoral tunnel placement was performed using two different techniques: TT [20] and OI [20]. Clinical evaluation was based on IKDC and KOOS scores and radiographic analysis with specific 3D CT scans. Tunnel coordinates were calculated using the Bernard-Hertel quadrant method to define the insertion point of the ACL., Results: excellent clinical results were achieved in both groups, which showed comparable IKDC and KOOS scores. Two failures were recorded, both in the TT group. In the high-to-low direction, the position of the femoral tunnel, as measured using the quadrant method, was too high in the TT group, compared to what was observed in the OI group: 10.5 ± 6.9% (0-29%) and 30.2 ± 5.4% (19-42%), (p=0.043)., Conclusions: we found that with the TT technique, compared with the OI technique, the femoral tunnel was located higher in the high-to-low direction and was in a slightly shallower position in the deep-to-shallow direction. Using the OI technique the femoral tunnel was in a position closer to the anatomical ACL footprint than with the TT technique. A femoral tunnel position far from the anatomical footprint of the native ACL would result in a higher failure rate., Level of Evidence: level II, prospective comparative study.