The walls of the femoral neck as an auxiliary tool for femoral stem positioning

2021 ◽  
pp. 112070002110407
Author(s):  
Samuel Morgan ◽  
Ofer Sadovnic ◽  
Moshe Iluz ◽  
Simon Garceau ◽  
Nisan Amzallag ◽  
...  
Keyword(s):  
Femoral Neck ◽  
Accurate Determination ◽  
Femoral Stem ◽  
Posterior Wall ◽  
Anterior Wall ◽  
Femoral Anteversion ◽  
Lower Limbs ◽  
Imaging Analysis ◽  
Femoral Condyles

Background: Femoral anteversion is a major contributor to functionality of the hip joint and is implicated in many joint pathologies. Accurate determination of component version intraoperatively is a technically challenging process that relies on the visual estimation of the surgeon. The following study aimed to examine whether the walls of the femoral neck can be used as appropriate landmarks to ensure appropriate femoral prosthesis version intraoperatively. Methods: We conducted a retrospective study based on 32 patients (64 hips) admitted to our centre between July and September 2020 who had undergone a CT scan of their lower limbs. Through radiological imaging analysis, the following measurements were performed bilaterally for each patient: anterior wall version, posterior wall version, and mid-neck femoral version. Anterior and posterior wall version were compared and evaluated relative to mid-neck version, which represented the true version value. Results: Mean anterior wall anteversion was 20° (95% CI, 17.6–22.8°) and mean posterior wall anteversion was −12° (95% CI, −15 to −9.7°). The anterior walls of the femoral neck had a constant of −7 and a coefficient of 0.9 (95% CI, −9.8 to −4.2; p  < 0.0001; R2 0.77). The posterior walls of the femoral neck had a constant of 20 and a coefficient of 0.7 (95% CI, 17.8–22.5; p  < 0.0001; R2 0.60). Conclusions: Surgeons can accurately obtain femoral anteversion by subtracting 7° from the angle taken between the anterior wall and the posterior femoral condyles or by adding 20° to the angle taken between the posterior wall and the posterior femoral condyles.

scholarly journals Evaluation of left ventricular hypertrophy in hypertensive patients with echocardiographic myocardial videodensitometry normalized by displacement

2010 ◽  
Vol 10 (4) ◽  
pp. 292-296 ◽  
Author(s):  
Xiao-Zhi Zheng ◽  
Lian-Fang Du ◽  
Hui-Ping Wang
Keyword(s):  
Left Ventricular Hypertrophy ◽  
Ventricular Hypertrophy ◽  
Accurate Determination ◽  
Normal Subjects ◽  
Posterior Wall ◽  
Left Ventricular ◽  
Hypertensive Patients ◽  
Tissue Tracking ◽  
Cardiovascular Morbidity And Mortality

Left ventricular hypertrophy (LVH) is an important predictor of cardiovascular morbidity and mortality. To investigate the feasibility of the myocardial grayscale intensity (GI) normalized by displacement (d) to discriminate between healthy and hypertrophic myocardium in hypertensive patients, sixty hypertensive patients and sixty age and sex-matched healthy volunteers were involved in this study. The peak d and the maximal GI [GI(max)] and minimal GI [GI(min)] for the middle interventricular septal (IVS) and the middle posterior wall (PW) at the level of papillary muscle were obtained from the standard parasternal long axis views using tissue tracking (TT) and videodensitometric analysis, respectively. The GI and the cyclic variation of GI (CVGI) normalized by d were calculated. The results showed that the d both for IVS and PW the amplitude of CVGI for IVS in hypertensive patients with LVH were smaller than the ones without LVH and the normal subjects. But, the CVGI/d both for IVS and PW in hypertensive patients with LVH were all greater than the ones without LVH and the normal subjects. Moreover, the parameter, CVGI/d correlated positively with left ventricular mass index (LVMI). So, the method employed in this study, videodensitometric analysis in combination with TT allow objective and accurate determination of LVH and CVGI/d is a sensitive indicator for hypertensive patients with LVH.

Ergebnisse der kombinierten Myokardszintigraphie und Radionuklidventrikulographie vor und nach transluminaler Koronarang ioplastik kritischer Koronararterienstenosen

1986 ◽  
Vol 25 (03) ◽  
pp. 106-113
Author(s):  
R. Grenz ◽  
F. D. Maul ◽  
R. Standke ◽  
H. Klepzig ◽  
G. Kober ◽  
...  
Keyword(s):  
Radionuclide Ventriculography ◽  
Posterior Wall ◽  
Myocardial Scintigraphy ◽  
Anterior Wall ◽  
Transluminal Angioplasty ◽  
Functional Improvement ◽  
Pathological Findings ◽  
Before And After ◽  
Stenosed Vessel

This study compares exercise radionuclide ventriculography (RNVG) and exercise myocardial scintigraphy with 201TI (MSC) both computed trisectorially. 137 patients before and after transluminal angioplasty (TCA) were investigated. While specificity equivalent was set at 90% for both methods (10% percentile of the controls [n = 29]) overall sensitivity for RNVG was 79% (n = 86) and for MSC 78% (n = 98). Sensitivity of RNVG for lesions of the posterior wall was lower than for the anterior wall: LAD stenoses 83% (n = 46), RCA stenoses 71 % (n = 17), and LCX stenoses 63% (n = 8). Sensitivity of MSC presents only a slight difference between anterior and posterior wall lesions: LAD stenoses 78% (n = 51), RCA stenoses 73% (n = 22), RCX stenoses 100% (n = 8). Reproducibility of pathological findings before and after non-successful TCA and the determination of the stenosed vessel was slightly better with MSC than with RNVG. Functional improvement after a successful TCA is predictable by MSC, whereas RNVG documents the functional improvement.

scholarly journals Imaging Markers of Hip Instability are Associated with Worse Outcomes at Two to Four-year Follow-up in Female Patients Undergoing Hip Arthroscopy for Femoroacetabular Impingement

2020 ◽  
Vol 8 (7_suppl6) ◽  
pp. 2325967120S0042
Author(s):  
Brandy Horton ◽  
Hugh West ◽  
Jenny Marland ◽  
James Wylie
Keyword(s):  
Hip Arthroscopy ◽  
Acetabular Dysplasia ◽  
Posterior Wall ◽  
Anterior Wall ◽  
Femoral Anteversion ◽  
Hip Instability ◽  
Female Patients ◽  
Imaging Markers ◽  
Fear Index

Objectives: To investigate the effect of radiographic markers of hip instability on outcomes of female patients undergoing hip arthroscopy for femoroacetabular impingement. Methods: This was a retrospective reviewof a prospectively collected cohort of females undergoing hip arthroscopy with a diagnosis of FAI treated with femoral osteoplasty with or without labral repair. iHOT-12 was collected preoperatively and at 2 to 4-year follow-up. Radiographs were reviewed and anterior wall index (AWI), posterior wall index (PWI), femoro-epiphyseal acetabular roof (FEAR) index, and lateral center edge angle (LCEA) were recorded in all patients. Computed tomography was used to quantify femoral anteversion in all patients. A laterally oriented FEAR index is considered positive (unstable), while a medially oriented fear index is considered negative (impingement/stable). An AWI of <0.30 and a PWI<0.80 were considered anterior wall deficient (AWD) and posterior wall deficient (PWD), respectively. Patients with borderline acetabular dysplasia (LCEA≤25) were groups as medially or laterally oriented FEAR index. Similarly, patients with borderline acetabular dysplasia(LCEA≤25) were groups as elevated femoral anteversion (>15 degrees) or not. Differences in means were tested using a students t-test or an analysis of variance with a post-hoc tukey’s test. Results: There were 175 Female patients with a mean age of 33 years. Mean follow up was 34.6 months. Mean preoperative iHOT12 was 30.4. Mean postoperative iHOT12 was 74.8. Mean FA was 11.7 (Range 1 to 34) degrees. There were 64 patients with an LCEA≤25, 138 patients had no AWD or PWD, 18 patients with an AWI <0.30 and 18 patients with a PWI <0.80. One patient was excluded from the analysis for having both an AWI<0.30 and a PWI<0.8. Patients with AWD had lower mean iHOT at follow up (54.5 compared with those with no wall deficiency 77.7, p=0.001.) Patents with PWD did not (72.4 compared with those with no wall deficiency 77.7, p=0.669.) Similarly, patients with AWD had lower mean iHOT improvement at follow up (24.2 compared with those with no wall deficiency 47.0, p=0.001). Patents with PWD did not (43.1 compared with those with no wall deficiency 47.0, p=0.808). Mean FEAR index was -7.1(Range -30 to 15) degrees. The FEAR index correlated with both the iHOT12 at follow up (-0.171, p=0.024) and the improvement in the iHOT12(-0.192, p=0.011). There were 31 patients with a laterally oriented FEAR index. These patients had worse iHOT12 at follow-up (64.9 points versus 77.0 points, p=0.037) and less improvement in iHOT12 (34.3 points versus 46.6 points, p=0.015). There were 110 patients with LCEA>25, 42 patients with LCEA≤25 with a medially oriented FEAR index and 23 patients with an LCEA≤25 with a laterally oriented FEAR index. Patients with LCEA≤25 and a laterally oriented FEAR index had worse iHOT12 at follow-up (60.7 points versus 78.9 points, p=0.005) and less improvement in iHOT12 from surgery (30.0 points versus 49.5 points, p=0.002) compared to those with an LCEA>25. There were 110 patients with LCEA>25, 46 patients with LCEA≤25 and FA <15 degrees and 17 patients with LCEA≤25 and FA≥15 degrees. Patients with LCEA≤25 had worse iHOT12 at follow-up (68.0 points versus 78.9 points, p=0.010) and less improvement in iHOT12 from surgery (36.0 points versus 49.5 points, p=0.001) compared to those with an LCEA>25. Patients with LCEA≤25 and FA≥15 degrees had worse iHOT12 at follow-up (59.5 points versus 78.9 points, p=0.008) and less improvement in iHOT12 from surgery (28.2 points versus 49.5 points, p=0.003) compared to those with an LCEA>25. In addition, patients with LCEA≤25 and FA<15 degrees had less improvement iHOT12 from surgery (38.0 points versus 49.4 points, p=0.026) compared to those with an LCEA>25. Conclusion: Imaging markers of hip instability, including borderline acetabular dysplasia, increased femoral anteversion, a laterally oriented FEAR index, and anterior wall deficiency are predictive of worse outcomes of hip arthroscopy for FAI in female patients. A more thoughtful imaging analysis of female patients preoperatively may identify patients at risk of worse outcomes after hip arthroscopy and may guide treatment with other joint preserving procedures, including periacetabular or femoral osteotomy.

scholarly journals Definition of ideal configuration for femoral neck screw fixation in older people

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Jialiang Guo ◽  
Weichong Dong ◽  
Shiji Qin ◽  
Yingze Zhang
Keyword(s):  
Femoral Neck ◽  
Femoral Shaft ◽  
Normal Subjects ◽  
Posterior Wall ◽  
Anterior Wall ◽  
Femoral Neck Fractures ◽  
Older Individuals ◽  
Mortality And Morbidity ◽  
Significant Difference ◽  
Neck Fracture

Abstract Femoral neck fractures are the most common injuries encountered by older individuals, and they are associated with high mortality and morbidity. Internal fixation to femoral neck fracture with cannulated screws placed with a configuration of an inverted triangle remain a feasible and effective treatment for femoral neck fractures. The objection of this research was to evaluate the femoral neck morphology, especially the shape of the femoral neck in Chinese people to find the optimal screw position and interval between the screws. 96 consecutive normal subjects without any previous proximal femur operation were reviewed. The patients’ information were collected from our database. The minimum of neck canal height (NCHM), neck canal width (NCWM) and inclination angle (AIA and PIA) were measured in different level. There was a significant difference between the AIA and PIA, neck canal height at inferior and superior 1/3 on posterior wall (NCHIP and NCHSP). Although there was a significant difference between the neck canal height at inferior and superior 1/3 on anterior wall (NCHIA and NCHSA, p < 0.001), but the changes were small. The shape of the anterior wall was perpendicular to the horizon and almost parallel with the FNA. In contrast, the shape of the posterior wall resembled a reverse question mark. The inverse triangular fixation was in accordance with the morphology of the femoral neck, and triangular fixation had a high risk of perforation, which may lead to nonunion and avascular necrosis. The anterior screw can be inserted easily with the help of a C-ARM, and the posterior screw positioned mildly posterior to the femoral shaft axis is recommended.

A quantitative approach to inner shell losses

1978 ◽  
Vol 36 (1) ◽  
pp. 526-527 ◽  
Author(s):  
R.D. Leapman ◽  
P. Rez ◽  
D.F. Mayers
Keyword(s):  
Energy Transfer ◽  
Cross Section ◽  
Cross Sections ◽  
Accurate Determination ◽  
Background Intensity ◽  
Core Excitation ◽  
Quantitative Basis ◽  
Cross Section Differential ◽  
Bound Electrons

Microanalysis by EELS has been developing rapidly and though the general form of the spectrum is now understood there is a need to put the technique on a more quantitative basis (1,2). Certain aspects important for microanalysis include: (i) accurate determination of the partial cross sections, σx(α,ΔE) for core excitation when scattering lies inside collection angle a and energy range ΔE above the edge, (ii) behavior of the background intensity due to excitation of less strongly bound electrons, necessary for extrapolation beneath the signal of interest, (iii) departures from the simple hydrogenic K-edge seen in L and M losses, effecting σx and complicating microanalysis. Such problems might be approached empirically but here we describe how computation can elucidate the spectrum shape.The inelastic cross section differential with respect to energy transfer E and momentum transfer q for electrons of energy E0 and velocity v can be written as

Fast calibration of CBED patterns for quantitative analysis

1993 ◽  
Vol 51 ◽  
pp. 674-675
Author(s):  
M.A. Gribelyuk ◽  
M. Rühle
Keyword(s):  
Reciprocal Lattice ◽  
Accurate Determination ◽  
Incident Beam ◽  
Crystal Thickness ◽  
Structure Model ◽  
Beam Direction ◽  
Transmitted Beam ◽  
Reciprocal Vector ◽  
On Line

A new method is suggested for the accurate determination of the incident beam direction K, crystal thickness t and the coordinates of the basic reciprocal lattice vectors V1 and V2 (Fig. 1) of the ZOLZ plans in pixels of the digitized 2-D CBED pattern. For a given structure model and some estimated values Vest and Kest of some point O in the CBED pattern a set of line scans AkBk is chosen so that all the scans are located within CBED disks.The points on line scans AkBk are conjugate to those on A0B0 since they are shifted by the reciprocal vector gk with respect to each other. As many conjugate scans are considered as CBED disks fall into the energy filtered region of the experimental pattern. Electron intensities of the transmitted beam I0 and diffracted beams Igk for all points on conjugate scans are found as a function of crystal thickness t on the basis of the full dynamical calculation.

Computer-Assisted High-Re Solution TEM

1990 ◽  
Vol 48 (1) ◽  
pp. 162-163
Author(s):  
F.A. Ponce ◽  
H. Hikashi
Keyword(s):  
Signal To Noise Ratio ◽  
Accurate Determination ◽  
Computer Software ◽  
Video Camera ◽  
Image Contrast ◽  
Objective Lens ◽  
Computer Assisted ◽  
Optical Parameters ◽  
Astigmatism Correction

The determination of the atomic positions from HRTEM micrographs is only possible if the optical parameters are known to a certain accuracy, and reliable through-focus series are available to match the experimental images with calculated images of possible atomic models. The main limitation in interpreting images at the atomic level is the knowledge of the optical parameters such as beam alignment, astigmatism correction and defocus value. Under ordinary conditions, the uncertainty in these values is sufficiently large to prevent the accurate determination of the atomic positions. Therefore, in order to achieve the resolution power of the microscope (under 0.2nm) it is necessary to take extraordinary measures. The use of on line computers has been proposed [e.g.: 2-5] and used with certain amount of success.We have built a system that can perform operations in the range of one frame stored and analyzed per second. A schematic diagram of the system is shown in figure 1. A JEOL 4000EX microscope equipped with an external computer interface is directly linked to a SUN-3 computer. All electrical parameters in the microscope can be changed via this interface by the use of a set of commands. The image is received from a video camera. A commercial image processor improves the signal-to-noise ratio by recursively averaging with a time constant, usually set at 0.25 sec. The computer software is based on a multi-window system and is entirely mouse-driven. All operations can be performed by clicking the mouse on the appropiate windows and buttons. This capability leads to extreme friendliness, ease of operation, and high operator speeds. Image analysis can be done in various ways. Here, we have measured the image contrast and used it to optimize certain parameters. The system is designed to have instant access to: (a) x- and y- alignment coils, (b) x- and y- astigmatism correction coils, and (c) objective lens current. The algorithm is shown in figure 2. Figure 3 shows an example taken from a thin CdTe crystal. The image contrast is displayed for changing objective lens current (defocus value). The display is calibrated in angstroms. Images are stored on the disk and are accessible by clicking the data points in the graph. Some of the frame-store images are displayed in Fig. 4.

Comparison of standardised lymphoscintigraphic function test and high resolution sonography of the lymphoedema of legs

Phlebologie ◽  
2008 ◽  
Vol 37 (05) ◽  
pp. 247-252 ◽  
Author(s):  
V. S. Brauer ◽  
W. J. Brauer
Keyword(s):  
Lower Leg ◽  
Clinical Findings ◽  
Lower Limbs ◽  
Fatty Tissue ◽  
Qualitative And Quantitative ◽  
Function Test ◽  
Unreliable Method ◽  
Negative Conclusion ◽  
Fine Disperse

SummaryPurpose: Comparison of qualitative and quantitative sonography with the lymphoscintigraphic function test and clinical findings in legs. Patients, methods: In 33 patients a lymphoscintigraphic function test of legs combined with measurement of lymph node uptake was performed and subsequently compared with sonography. Sonographic criteria were: Thickness of cutis, thickness of subcutanean fatty tissue and presence of liquid structures or fine disperse tissue structure of lower limbs, foots and toes. Results: In 51 legs uptake values lie in the pathologic area, in four legs in the grey area and in ten legs in the normal area. The cutis thickness in the lower leg shows no significant correlation with the uptake. The determination of the thickness of the subcutanean fatty tissue of the lower leg and of the cutis thickness of the feet turned out to be an unreliable method. In 47% of the medial lower legs and in 57% of the lateral lower legs with clinical lymphoedema sonography is falsely negative. Conclusion: Early lymphoedema is only detectable with the lymphoscintigraphic function test. In the case of clinical lymphoedema clinical examination is more reliable than sonography.

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