Quadrant Method Research Articles

Factors Influencing Graft Impingement on the Wall of the Intercondylar Notch After Anatomic Double-Bundle Anterior Cruciate Ligament Reconstruction

Background: Anatomic placement of the bone tunnel reportedly reduces impingement of the graft with the intercondylar roof, but as a trade-off, the risk of impingement with the lateral wall of the intercondylar notch would increase instead in anatomic double-bundle anterior cruciate ligament (ACL) reconstruction. Purpose: The 2 grafts for the anteromedial bundle (AMB) and posterolateral bundle (PLB) were separately analyzed for the frequency of and risk factors for graft impingement on the wall of the intercondylar notch. Study Design: Case control study; Level of evidence, 3. Methods: A total of 51 patients (53 knees) who underwent primary anatomic double-bundle ACL reconstruction were enrolled. Based on the graft orientation plane reconstructed with 3-dimensional imaging software, graft-wall impingement was defined as overlap between the lateral wall of the notch and the line connecting each center of the intra-articular apertures of the femoral and tibial bone tunnels. The rate of wall impingement was assessed for each bundle. Parameters for bone tunnel positioning in the femur and tibia, notch width index, and knee joint rotation angle were compared between patients with and without wall impingement. The most important risk factors for wall impingement were assessed by logistic regression analysis. Results: Wall impingement for the AMB was observed in 22 knees (42%), whereas no patients exhibited wall impingement for the PLB. Regarding femoral bone tunnel positioning according to the quadrant method, the AMB bone tunnel was placed significantly higher in impingement-positive patients than in impingement-negative patients (P = .03). Regarding tibial tunnel positioning, the tunnel was placed significantly more anteriorly (P = .02) and laterally (P = .02) in the impingement-positive group than in the impingement-negative group. Bone tunnels positioned 48% to 50% from the medial border of the tibia demonstrated a 100% incidence of wall impingement. Based on logistic regression analysis, lateral deviation of the AMB tibial bone tunnel was significantly associated with wall impingement (odds ratio, 1.403; P = .048). Conclusion: The tibial bone tunnel position in the coronal orientation was most likely associated with wall impingement. Considering that tibial bone tunnels are generally created with the knee in 90° of flexion and move laterally as the knee extends because of screw-home movement, the AMB bone tunnel for the tibia should be positioned as medially as possible within its footprint to minimize the risk of wall impingement after anatomic double-bundle ACL reconstruction.

Anatomic Single Bundle Anterior Cruciate Ligament Reconstruction by Low Accessory Anteromedial Portal Technique: An In Vivo 3D CT Study.

PurposeProper femoral tunnel position is important for anatomical reconstruction of the anterior cruciate ligament (ACL). The purpose of this study was to evaluate the positions of femoral and tibial tunnels created using an accessory anteromedial portal technique in single bundle ACL reconstruction.Materials and MethodsThe femoral tunnel was targeted at the mid-portion of the ACL bundles. We evaluated postoperative computed tomography scans of 32 patients treated by ACL reconstruction using a free-hand low accessory anteromedial portal technique. On the tibial side, the tunnel position was evaluated using Tsukada's method. On the femoral side, the position was evaluated using 1) the quadrant method, 2) Mochizuki's method, 3) Mochizuki's method, and 4) Takahashi's method. Tunnel obliquity was also evaluated.ResultsThe mean tibial tunnel position was located at 44.6%±2.5% anterior from the anterior margin and 48.0%±3.0% in medial from the medial margin. The mean femoral tunnel position was located at the center between the anteromedial and posterolateral bundles: Quadrant method, 26.7%±2.7%/30.0%±2.9%; Watanabe's method, 37.7%±2.5%/26.6%±2.2%; Mochizuki's method, 38.7%±2.7%; Takahashi's method, 21.8%±2.2%. The mean femoral tunnel obliquity was 57.7°±6.2° in the sagittal plane and 49.9°±5.6° in the coronal plane.ConclusionsIn anatomic single bundle ACL reconstruction, the low anteromedial portal technique can restore accurate position of the native footprint. Accurate femoral tunnel position facilitates recovery of stability and decreases graft failure rate.

River ecosystem assessment and application in ecological restorations: A mathematical approach based on evaluating its structure and function

The river is an essential part of water resources, which has unique ecological structure and function. With the rapid socio-economic development, the improper use of water resources has led to a series of structural and functional decline of the river system, such as water pollution, environmental degradation and river shrinkage. How to restore damaged river ecosystems to an ecologically healthy status has become one of the important environmental issues, which is the key to achieve the goal of productivity improvement, ecosystem balance and sustainable development. And also, the structure and function of the river ecosystem should be pre-assessed before the restoration. In this paper, the Liangshui River, a tributary of Daling River in the arid region of western Liaoning Province, is selected as a study site. An assessment index system involving 21 defined indices on structure and function of river ecosystem is firstly established. A mathematical method for comprehensive assessing the structure and function of river ecosystem is proposed based on the Set Pair Analysis (SPA) and Quadrant Method. Then, the evaluation value is gained at the ecosystem level. The result shows that the assessment value of structure and function is −0.513 and −0.208, respectively, which means that the Liangshui River ecosystem is defective in structure and sub-healthy in function. It is necessary to choose potential development emphasized on the structurally rehabilitating of the Liangshui River ecosystem. Based on the above, ecological engineering measures and suggestions are recommended to preserve the health of river ecosystem.

Anatomic Single-Bundle ACL Reconstruction Is Possible with Use of the Modified Transtibial Technique

Anatomic anterior cruciate ligament (ACL) reconstruction is essential to the restoration of normal knee kinematics and to achieving successful results after ACL surgery. The purpose of this study was to evaluate whether anatomic single-bundle ACL reconstruction can be performed with use of the modified transtibial technique such that the tunnel characteristics are not substantially different from those of the anteromedial transportal technique, with comparable clinical results. One hundred and four patients underwent single-bundle ACL reconstruction performed with use of either the modified transtibial technique or the anteromedial transportal technique. Each group included fifty-two patients retrospectively matched on the basis of age, sex, and body mass index. All patients had postoperative computed tomography (CT) and a minimum duration of follow-up of twenty-four-months. CT parameters, including tunnel position, tunnel length and shape, and graft obliquity, were evaluated. Clinical assessments were based on manual laxity tests, arthrometric analysis, and clinical scores recorded preoperatively and at the time of follow-up. The femoral tunnel was placed at a slightly inferior and anterior position with use of the modified transtibial technique compared with the anteromedial transportal technique, but the difference was not significant (superior-inferior mean [and standard deviation], 35.7% ± 3.1% versus 33.9% ± 4.1%, p > 0.05, and anterior-posterior mean, 31.6 ± 6.8% versus 35.1 ± 6.9%, p > 0.05, as assessed with use of the quadrant method). The femoral tunnel length was significantly longer (p < 0.05) and the tibial tunnel length was significantly shorter (p < 0.05) with use of the modified transtibial technique compared with the anteromedial transportal technique (mean femoral tunnel length, 40.5 ± 4.2 mm versus 34.4 ± 2.6 mm and mean tibial tunnel length, 32.3 ± 3.1 mm versus 35.5 ± 2.7 mm); however, tunnel length was sufficient to allow for adequate fixation. There were no significant differences between the two groups in terms of tibial tunnel position, graft obliquity, tibial tunnel widening, and clinical results. Tunnel characteristics including anatomic position, graft obliquity, and tunnel widening after single-bundle ACL reconstruction performed with use of the modified transtibial technique were not significantly different from those of the anteromedial transportal technique, and clinical results were comparable.

Low inter- and intraobserver variability allows for reliable tunnel measurement in ACL reconstruction using the quadrant method

Correct anatomic tunnel positions are essential in anterior cruciate ligament (ACL) reconstruction. To establish recommendations for tunnel positioning based on anatomical findings and to compare tunnel positions with clinical results, different radiological measurement methods as the quadrant method exist. Comparing the data of different observers requires the validation of the reliability of measurement methods. The purpose of this study therefore was to determine the reliability of the quadrant method to measure tunnel positions in ACL reconstruction. The hypothesis was, that the quadrant method shows a low inter- and intraobserver variability. In a test/retest scenario 20 knee surgeons were asked to determine defined tunnel positions in five lateral radiographs applying the quadrant method. Rotation, angle deviation, height and depth of the quadrant as well as absolute and relative tunnel positions of each observation were measured along referenced scales. Mean sizes and angle deviations of the quadrants, tunnel positions and deviations between the test/retest positions were calculated as well as standard deviations and range. Interobserver variability analyses, to plan as well as to determine tunnel positions in ACL reconstruction, showed a mean variability (SD) of <1 mm, with ranges of 2.5 mm for planning and 3.7 mm for determination of tunnel positions using the quadrant method. Intraobserver analysis showed mean variability with deviations of <1 mm and maximum standard deviations of 0.7 mm and ranges of up to 2.3 mm. We confirmed the hypothesis that the quadrant method has a low inter- and intraobserver variability. Based on the presented validation data, the quadrant method can be recommended as reliable method to radiographically describe insertion areas of the ACL as well as to determine tunnel positions in ACL reconstruction intra and postoperatively.

In VivoThree-Dimensional Imaging Analysis of Femoral and Tibial Tunnel Locations in Single and Double Bundle Anterior Cruciate Ligament Reconstructions

BackgroundAnatomic footprint restoration of anterior cruciate ligament (ACL) is recommended during reconstruction surgery. The purpose of this study was to compare and analyze the femoral and tibial tunnel positions of transtibial single bundle (SB) and transportal double bundle (DB) ACL reconstruction using three-dimensional computed tomography (3D-CT).MethodsIn this study, 26 patients who underwent transtibial SB ACL reconstruction and 27 patients with transportal DB ACL reconstruction using hamstring autograft. 3D-CTs were taken within 1 week after the operation. The obtained digital images were then imported into the commercial package Geomagic Studio v10.0. The femoral tunnel positions were evaluated using the quadrant method. The mean, standard deviation, standard error, minimum, maximum, and 95% confidence interval values were determined for each measurement.ResultsThe femoral tunnel for the SB technique was located 35.07% ± 5.33% in depth and 16.62% ± 4.99% in height. The anteromedial (AM) and posterolateral (PL) tunnel of DB technique was located 30.48% ± 5.02% in depth, 17.12% ± 5.84% in height and 34.76% ± 5.87% in depth, 45.55% ± 6.88% in height, respectively. The tibial tunnel with the SB technique was located 45.43% ± 4.81% from the anterior margin and 47.62% ± 2.51% from the medial tibial articular margin. The AM and PL tunnel of the DB technique was located 33.76% ± 7.83% from the anterior margin, 45.56% ± 2.71% from the medial tibial articular margin and 53.19% ± 3.74% from the anterior margin, 46.00% ± 2.48% from the medial tibial articular margin, respectively. The tibial tunnel position with the transtibial SB technique was located between the AM and PL tunnel positions formed with the transportal DB technique.ConclusionsUsing the 3D-CT measuring method, the location of the tibia tunnel was between the AM and PL footprints, but the center of the femoral tunnel was at more shallow position from the AM bundle footprint when ACL reconstruction was performed by the transtibial SB technique.

Association between fetal weight and amniotic fluid index in women of Central India

Background:The placenta is important for fetal growth and well-being. Defective placentation and impaired placental circulation may result in anomalies in fetal growth. Placental volume in the second trimester appears to be closely related to the neonatal weight. The association of body weight with urine output has been observed in human neonates. Our goal is to assess the association of the amniotic fluid index (AFI) with the estimated fetal weight (EFW).Materials and Methods:Thirteen hundred and ninety-three pregnant women were prospectively studied by means of an ultrasound over a 12–month period. The fetal weight (FW) was estimated using a combination of fetal parameters – bi-parietal diameter, fetal trunk cross-sectional area, and femur length. AFI was assessed using the four quadrant method. The level of statistical significance was set at P ≤ 0.05.Results:There was no statistically significant association between AFI and EFW (P > 0.05; r = 0.413). We also did not find a significant association between AFI and EFW for all subdivisions of gestation age, except in the 24 – 28 weeks and 29 – 32 weeks’ groups.Conclusion:The FW calculations and amniotic index show a variation in values in late pregnancy. There does not appear to be a linear association between the ultrasound estimate of FW and the amniotic index. The implication of this is that the fetal size need not be taken into cognizance when alterations in amniotic fluid values are noted.

PENELUSURAN POTENSI MIKROBA ENDOFIT DARI RIMPANG PAKU KEPALA TUPAI (Drynaria quercifolia J.Smith) SEBAGAI PENGHASIL SENYAWA ANTIBIOTIKA

This research object to obtain abd determine the activity of antibiotics microbial isolates from endophyticpakukepalatupai (Drynariaquercifolia J. Smith) as a producer of antibiotic compounds. Methods research is using the method in a medium cast nutrient agar and potato dextrose agar with a dilution of 10 -1 to 10 -5 . Result showed that there were 5 active isolates on thosetwo medium, identification of isolates bacterial and fungi. Then, the bacteria and fungi isolates purified by quadrant method on nutrient agar and potato dextrose agar medium were in mikroskopic. To produce antibiotic compound fermentation carried out by maltose yeast broth. The results of testing the activity of an antibiotic fermentation with agar diffusion method, results showed that the bacterial active against Bacillus subtilis, Pseudomonas aeruginosa, Streptococcus mutans, Escherichia coli and fungal isolates aktifagains candida albicans. Identification of endophyte microbe isolates carried out by gram staining. Result obtained showed that all isolates of the bacteria were negative Gram and coccus and bacil from. Key word : Antibiotic, Microbial Endophyte, Drynaria quercifolia J. Smith

A modified quadrant method for describing the femoral tunnel aperture positions in ACL reconstruction using two-view plain radiographs

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. 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 1year 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). 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. 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. IV.

Three-dimensional computed tomography evaluation of anterior cruciate ligament footprint for anatomic single-bundle reconstruction

Femoral and tibial footprint coordinates have been well studied in double-bundle anterior cruciate ligament (ACL) reconstruction. However, in a single-bundle reconstruction approach, the central coordinate of femoral and tibial footprints have not been determined. The purpose of this study was to describe the central point locations of the ACL footprints visualized by three-dimensional computed tomography (3D CT) images and analysed by the quadrant method. Eight cadaveric knees were dissected, and the central points of ACL femoral and tibial footprints were marked and analysed using 3D CT images. In the present study, the means (and standard deviation) of ACL femoral footprint dimensions were in the ventral-dorsal plane and in the cranial-caudal plane 9.4 ± 0.8 and 15.6 ± 0.9 mm, respectively. In the tibial side, the means of ACL footprint dimensions were in the anterior-posterior and in the medial-lateral 18.5 ± 1.9 and 15.5 ± 1.0 mm, respectively. In the tomographic analyses, the means of femoral central location coordinates in the ventral-dorsal (y) and in the cranial-caudal (x) axes were 35.3 ± 4.5 and 30.0 ± 1.6 %, respectively. The means of tibial central location coordinates were in the anterior-posterior (y) and in the medial-lateral (x) axes, respectively: 40.5 ± 5.3 and 50.2 ± 1.3 %, respectively. These computed tomographic coordinates might help future studies as a reference on ACL single-bundle anatomic reconstruction, with respect to the management of ACL revision surgery or in symptomatic patients after ACL reconstruction. Improvements in three-dimensional image acquisition could facilitate its intraoperative applicability in the coming years.

Clinical outcome of anatomic double-bundle ACL reconstruction and 3D CT model-based validation of femoral socket aperture position

The purpose of this study was to evaluate the clinical results of anatomic double-bundle (DB) anterior cruciate ligament (ACL) reconstruction in which anatomic position of femoral socket apertures was validated using three-dimensional (3D) computed tomography (CT) modelling. Anatomic DB ACL reconstructions with hamstring autografts were performed in 34 patients. Two femoral sockets were created through a far anteromedial (AM) portal behind the lateral intercondylar ridge with the assistance of intraoperative 3D fluoroscopic navigation. Femoral tunnel aperture positioning was investigated postoperatively using 3D CT images in all patients. Clinical results were also evaluated subjectively and objectively at least up to 2 years. Measurement of the AM and the posterolateral (PL) femoral socket locations on the 3D CT images using the quadrant method showed that the centre of the AM socket aperture was located at a depth of 21.0 ± 4.1% and a height of 30.5 ± 9.3% and that of the PL socket aperture was located at a depth of 31.3 ± 5.8% and a height of 57.2 ± 7.7%. The femoral socket locations were considered as anatomic in accordance with previous cadaveric studies examining the positions of ACL femoral insertion site. Subjectively, the mean Lysholm score was 96.9 ± 4.0 points. According to IKDC final objective scores, 26 knees (76%) were objectively graded as normal, 8 (24%) as nearly normal, and 0 (0%) as abnormal or severely abnormal. Postoperative side-to-side anterior translation measured with a KT-2000 arthrometer averaged 0.7 ± 1.2 mm. DB ACL reconstructions in which femoral socket apertures were validated anatomically using 3D CT provided satisfactory short-term results. Case series, Level IV.

The Accuracy of Femoral Tunnel in Remnant Preserved Anatomic Double-Bundle Anterior Cruciate Ligament Reconstruction Analyzed Three-Dimensional Computed Tomography

The position of anteromedial and posterolateral bone tunnels in twenty-five knees of anatomical ACL reconstruction were evaluated using quadrant method with three-dimensional computed tomography. Remaining connected ACL remnants were preserved in thirteen of their knees using fluoroscopic assisted surgery. Tunnels of remnant preserved knee were located in anatomic ACL insertion.

Radiographic localization and isometry of the origin and insertion of the canine cranial cruciate ligament

To radiographically define the anatomic origin and insertion of the cranial cruciate ligament translated to the lateral radiographic projection of the stifle (CrCL-Lo and CrCL-Li, respectively), to correlate these landmarks for identification of the CrCL-Lo intraoperatively, and to compare the isometry of the CrCL-Lo to the lateral fabella. Experimental study. Pelvic limbs (n = 12) from dogs weighing 13-26 kg. A radiographic quadrant method was used to localize the CrCL-Lo. Mediolateral radiographic projections of each stifle were taken through a range of motion. Maximum percent change in length between each tibial marker and femoral marker during range of motion determined isometry. The CrCL-Lo is located at the caudal 33% and distal 50% of the lateral femoral condyle using Blumensaat's line or a line from the origin of the long digital extensor (LDE) to the lateral fabella, with no significant difference (P = .766) between the 2 reference lines. The CrCL-Li is located at the proximal 20% of the tibial plateau. No significant difference (P < .05) in isometry was found between the CrCL-Lo and lateral fabella. The CrCL-Lo is located at the caudal 1/3 and distal ½ of the lateral femoral condyle. The CrCL-Lo and lateral fabella are not significantly different in isometry when used as a proximal anchor point in extracapsular stifle stabilization.

Basis weight uniformity analysis in nonwovens

It is widely recognized that nonwoven basis weight uniformity affects various properties of nonwovens, including appearance, physical properties, or mechanical properties. However, it is one of the nonwoven characteristics that is most difficult to characterize. This paper reports on the methodology based on the well-known quadrant method that objectively quantifies uniformity of nonwoven fabrics.

자전거 이용 시설물의 균형적인 관리를 위한 평가 - 송파구 역세권을 대상으로

Continuous management of bicycle facilities is needed, as uses of bicycles are increased. In the previous studies, evaluation of bicycle facilities were performed mainly from the surveys to bicycle users and experts. This study aims to evaluate the facilities for bicycle uses by setting up the quantitative assessing measures for the purpose of contributing to balanced management of the facilities for bicycle uses. Based on the existing measures provided in the previous studies about conditions for bicycles users, the variables of the facilities that are available and quantifiable were derived, and the scales of the facilities were set up. For evaluation, the station influence areas in Songpa District were selected as test areas. The methods for analysis were, first, to carry out the 'bicycle roads-facilities' analysis, which was modified from quadrant method. Consequently, individual facilities and station areas were relatively examined. Second, by principal component analysis, bicycle facilities were analyzed in a general and integrated way. From that, the variables sharing common characteristics were grouped, similar types of stations influence areas were found out, and then the groups were ranked.

Evaluation de la ressource en teck, Tectona grandis L.f., des plantations privées du Sud-Bénin

Au Sud-Bénin, les plantations privées de teck ont été installées à un rythme croissant ces trois dernières décennies. Pour combler le vide d'informations fiables sur cette ressource, une démarche méthodologique a été conçue en vue de quantifier et caractériser les plantations privées de teck et de mieux connaître les propriétaires privés impliqués dans la production de teck au Bénin. Celle-ci s'apparente à un échantillonnage boule de neige (Ebn) ou snowball sampling avec trois types d'acteurs, les agents des services forestiers, les chefs de village et les propriétaires de plantations de teck ou leur représentant. Les données collectées sont le profil socio-économique du propriétaire, le descriptif général de ses plantations et la caractérisation dendrométrique de ces dernières. En vue d'évaluer la capacité de l'Ebn, un échantillonnage par quadrats a été mis en place. L'Ebn a permis d'identifier 1 002 propriétaires et de recenser 861,10 ha de plantations de teck, Tectona grandis L.f. Près de 69 % des plantations ont moins de 6 ans, comprenant 12,4 % de jeunes plantations et 56,7 % de taillis. Les futaies âgées de plus de 20 ans ne représentent qu'une infime proportion de la ressource en teck (0,2 %). Avec un taux de boisement global très faible estimé à 3,58 %, un taux de détection de l'Ebn de 68,6 %, la surface totale en teck est estimée à 1 255,3 ha avec les limites de confiance de 1 084,5 ha et 1 574,2 ha. La géodatabase construite lors de l'application de l'Ebn sur la commune de Toffo constitue indéniablement une amorce prometteuse dans la construction d'un réseau d'acteurs impliqués dans la culture du teck. L'intérêt d'une telle approche dans le contexte d'une foresterie paysanne justifie l'application de l'Ebn aux autres communes.

Building the Model of Near-Level Coal Deposit

Based on the theory of regular block model constructing of open pit mine, a regular column model was used for a near-level coal deposit to build model. Taking column as unit, inverse distance method was used to valuate. The relevant attributes of each coal deposit in each column was recorded, containing elevation, thickness, coal quality parameters of each coal seam. Based on the ground surface contour, surface level of column model was estimated. According to the problem meeting in the practical application, virtual drill holes, angle exclusive and quadrant method were used to deal with faults, seam boundary and cluster-effect. The application showed that using regular column model could describe the location and thickness variation of seam well and solved the problem which was difficult to calculate the volume of coal and rock accurately when 3D regular block model had coal combined with rock modules.

Critérios de calagem e teores críticos de fósforo e potássio em latossolos sob plantio direto no centro-sul do Paraná

A adoção do plantio direto (PD) em substituição ao preparo convencional promove alterações na dinâmica de nutrientes e na acidez no solo, podendo influenciar as relações solo-planta e, portanto, os critérios de manejo da fertilidade do solo. Este estudo teve como objetivo determinar os critérios de recomendação de calagem e os teores críticos de fósforo (P) e potássio (K) para o sistema de rotação de culturas envolvendo soja, milho, trigo, cevada e aveia branca, amplamente adotado na região Centro-Sul do Paraná. O estudo foi com base em 13 experimentos de campo conduzidos em Latossolos Brunos em longo prazo em PD (&gt;15 anos), nos municípios de Guarapuava, Pinhão e Candói. Desses, cinco envolveram calagem e oito adubação de P e K. Em amostras de solo das camadas de 0-0,10 e 0,10-0,20 m, foi determinado o pH (CaCl2) e calculada a saturação por bases (V%) nos experimentos de calagem e os teores de P e K disponível (Mehlich-1) nos experimentos de adubação. O método dos quadrantes foi utilizado para determinar os critérios de recomendação de calagem; e o nível crítico de pH e V% consistiu no valor em que, acima do qual, as culturas apresentaram rendimento relativo (RR) superior a 90 % e nunca inferior a 80 %. A relação entre os teores de P e K e os valores de RR foi verificada pela equação de Mitscherlich, sendo o teor crítico aquele correspondente ao RR de 90 %. Os resultados indicaram que os níveis críticos relacionados à acidez e disponibilidade de P e K foram maiores para a camada de 0-0,10 m do que para a de 0-0,20 m. A cultura da soja foi mais sensível à acidez do solo, enquanto os cereais de inverno foram mais exigentes em P e K. Tomando-se como referência as culturas mais restritivas do sistema de rotação e a camada de 0-0,20 m, os níveis críticos para calagem foram pH (CaCl2) de 4,9 e saturação por bases de 60 %, enquanto os teores críticos para adubação foram 8 mg dm-3 de P e 0,30 cmol c dm-3 de K para Latossolos cultivados no longo prazo em sistema PD na região Centro-Sul do Paraná.

Three-Dimensional Reconstruction Computed Tomography Evaluation of Tunnel Location during Single-Bundle Anterior Cruciate Ligament Reconstruction: A Comparison of Transtibial and 2-Incision Tibial Tunnel-Independent Techniques

BackgroundAnatomic tunnel positioning is important in anterior cruciate ligament (ACL) reconstructive surgery. Recent studies have suggested the limitations of a traditional transtibial technique to place the ACL graft within the anatomic tunnel position of the ACL on the femur. The purpose of this study is to determine if the 2-incision tibial tunnel-independent technique can place femoral tunnel to native ACL center when compared with the transtibial technique, as the placement with the tibial tunnel-independent technique is unconstrained by tibial tunnel.MethodsIn sixty-nine patients, single-bundle ACL reconstruction with preservation of remnant bundle using hamstring tendon autograft was performed. Femoral tunnel locations were measured with quadrant methods on the medial to lateral view of the lateral femoral condyle. Tibial tunnel locations were measured in the anatomical coordinates axis on the top view of the proximal tibia. These measurements were compared with reference data on anatomical tunnel position.ResultsWith the quadrant method, the femoral tunnel centers of the transtibial technique and tibial tunnel-independent technique were located. The mean (± standard deviation) was 36.49% ± 7.65% and 24.71% ± 4.90%, respectively, from the over-the-top, along the notch roof (parallel to the Blumensaat line); and at 7.71% ± 7.25% and 27.08% ± 7.05%, from the notch roof (perpendicular to the Blumensaat line). The tibial tunnel centers of the transtibial technique and tibial tunnel-independent technique were located at 39.83% ± 8.20% and 36.32% ± 8.10%, respectively, of the anterior to posterior tibial plateau depth; and at 49.13% ± 4.02% and 47.75% ± 4.04%, of the medial to lateral tibial plateau width. There was no statistical difference between the two techniques in tibial tunnel position. The tibial tunnel-independent technique used in this study placed femoral tunnel closer to the anatomical ACL anteromedial bundle center. In contrast, the transtibial technique placed the femoral tunnel more shallow and higher from the anatomical position, resulting in more vertical grafts.ConclusionsAfter single-bundle ACL reconstruction, three-dimensional computed tomography showed that the tibial tunnel-independent technique allows for the placement of the graft closer to the anatomical femoral tunnel position when compared with the traditional transtibial technique.

Evaluation of Femoral Tunnel Positioning Using 3-Dimensional Computed Tomography and Radiographs after Single Bundle Anterior Cruciate Ligament Reconstruction with Modified Transtibial Technique

BackgroundThe purpose of this study is to report a modified transtibial technique to approach the center of anatomical femoral footprint in anterior cruciate ligament (ACL) reconstruction and to investigate the accurate femoral tunnel position with 3-dimensional computed tomography (3D-CT) and radiography after reconstruction.MethodsFrom December 2010 to October 2011, we evaluated 98 patients who underwent primary ACL reconstruction using a modified transtibial technique to approach the center of anatomical femoral footprint in single bundle ACL reconstruction with hamstring autograft. Their femoral tunnel positions were investigated with 3D-CT and radiography postoperatively. Femoral tunnel angle was measured on the postoperative anteroposterior (AP) radiograph and the center of the femoral tunnel aperture on the lateral femoral condyle was assessed with 3D-CT according to the quadrant method by two orthopedic surgeons.ResultsAccording to the quadrant method with 3D-CT, the femoral tunnel was measured at a mean of 32.94% ± 5.16% from the proximal condylar surface (parallel to the Blumensaat line) and 41.89% ± 5.58% from the notch roof (perpendicular to the Blumensaat line) with good interobserver (intraclass correlation coefficients [ICC], 0.766 and 0.793, respectively) and intraobserver reliability (ICC, 0.875 and 0.893, respectively). According to the radiographic measurement on the AP view, the femoral tunnel angles averaged 50.43° ± 7.04° (ICC, 0.783 and 0.911, respectively).ConclusionsOur modified transtibial technique is anticipated to provide more anatomical placement of the femoral tunnel during ACL reconstruction than the former traditional transtibial techniques.