Inter- and intra-operator variability associated with extracapsular suture tensioning

2012 ◽  
Vol 25 (06) ◽  
pp. 472-477 ◽  
Author(s):  
E. A. Buffa ◽  
A. M. Marchevsky ◽  
J. Heller ◽  
A. P. Moores ◽  
M. Farrell ◽  
...  
Keyword(s):  
Ex Vivo ◽  
Cruciate Ligament ◽  
Mean Difference ◽  
Marked Variation ◽  
Limits Of Agreement ◽  
Cranial Cruciate Ligament ◽  
Suture Tension ◽  
Clinical Consequences ◽  
The Mean ◽  
The Difference

SummaryObjectives: To determine inter- and intra- operator variability associated with extracapsular suture tensioning as performed during lateral fabello-tibial suture placement.Study design: Ex vivo study.Methods: Fifteen Greyhound cadaveric pelvic limbs were prepared by cutting the cranial cruciate ligament and placing an extracapsular fabello-tibial suture. On two occasions, three surgeons tensioned the extracapsular suture of each stifle. Stifles were returned to 135 degrees of flexion and the suture tension was measured using a commercially available suture tensioner with inbuilt tensiometer.Statistical analysis: Intra-operator and inter-operator agreement were assessed using the limits of agreement method. A linear mixed effects model was specified to assess the effect of operator, repeated estimates and stifle order on tension applied.Results: The mean difference within the three operators ranged from 0 to 14.7N. With 95% limits of agreement, on most occasions for all three operators, the difference was between –31.7 and 41.0 N. The mean difference between the three operators ranged from 6.0 to 30.7 N. With 95% limits of agreement, on most occasions the difference between operators was between –25.6 and 62.5 N.Clinical significance: Marked variation exists in the tension applied during fabello- tibial suture application, both within and between surgeons. This variation may lead to inconsistent clinical outcomes. Further studies are required to determine the clinical consequences of this marked variation in extracapsular suture tensioning.

Lateral and medial tibial plateau angles in normal dogs

2014 ◽  
Vol 27 (02) ◽  
pp. 135-140 ◽  
Author(s):  
M. K. Ocal ◽  
S. S. Sabanci
Keyword(s):  
Tibial Plateau ◽  
Cruciate Ligament ◽  
Axial Rotation ◽  
T Test ◽  
Medial Tibial Plateau ◽  
Lateral Tibial Plateau ◽  
Cranial Cruciate Ligament ◽  
Significant Difference ◽  
The Mean ◽  
The Difference

SummaryTo measure lateral and medial tibial plateau angle values in isolated canine tibiae and to compare lateral and medial tibial plateau angle values between dogs based on sex and breed.Tibiae of 90 dogs from 24 different breeds were used. Photographs were taken of the medial and lateral aspects of the tibiae for measurement of the medial and lateral tibial plateau angles. Additionally, the medial tibial plateau angle was measured from radiographs of the tibiae. Two-way analysis of variance was used to test the effects of side, sex and breed on the medial and lateral tibial plateau angles as measured from photographs as well as the medial tibial plateal angles as measured from radiographs. The photographic and radiographic medial tibial plateau angles were compared by paired t-test, whereas the medial and lateral photographic tibial plateau angles were compared by t-test.When all dogs were included in the analysis, the difference between the mean medial tibial plateau angle (24.0 ± 3.19°) and the mean lateral tibial plateau angle (25.5 ± 3.84°) as measured from photographs was significant (p <0.05). The difference in the photographic medial tibial plateau angle between male and female dogs was significant (p <0.05), whereas the difference in the photographic lateral tibial plateau angle between sexes was not significant. There was a significant difference between the medial and lateral tibial plateau angles as measured from photographs in male dogs (p <0.05) but not in female dogs. Breed comparisons also showed significant differences for the photographic lateral tibial plateau angle (p <0.05).The axial rotation of the femoral condyles on the tibial plateau is probably affected by the discrepancy between the medial and lateral tibial plateau angles, and this difference in certain breeds might influence the prevalence of cranial cruciate ligament disease.

scholarly journals Mechanical testing of newly developed biomaterial designed for intra-articular reinforcement of partially ruptured cranial cruciate ligament: ex vivo pig model

2014 ◽  
Vol 83 (1) ◽  
pp. 55-60 ◽  
Author(s):  
Petra Fedorová ◽  
Robert Srnec ◽  
Jan Pěnčík ◽  
Pavel Schmid ◽  
Evžen Amler ◽  
...  
Keyword(s):  
Mechanical Testing ◽  
Ex Vivo ◽  
Cruciate Ligament ◽  
Maximum Load ◽  
Fixation Failure ◽  
Cranial Cruciate Ligament ◽  
Initial Fixation ◽  
The Mean ◽  
Group 2 ◽  
Group 1

The study deals with mechanical testing of newly developed material polyethylene terephtalate coated with polycaprolactone nanofibers in combination with biodagradable Hexalon ACL/PCL screws as a new possibility of intra-articular reinforcement of partially ruptured cranial cruciate ligament. Four groups ofex vivomodels of pig stifle joints were prepared and tested: a model with intact CCL (group 1), a model with partial CCL rupture (group 2), a model with CCL rupture stabilized with 7 mm Mersilene®strip (group 3), and a model with CCL rupture stabilized with 5 mm PET/PCL biomaterial strip (group 4). The models were loaded in the standing angle of 100° and the maximum load (N) and the shift (mm) were monitored. The mean maximum peak power and the shift were 1266.0 ± 146.9 N and 13.7 ± 2.5 mm for group 1, and 1164.7 ± 228.2 N and 1 6.8 ± 3.3 mm for group 2, respectively. In all cases after reaching the maximum load, a tibial fracture occurred but never a CCL rupture. In groups 3 and 4, the initial fixation failure occurred in the mean values of 375.7 ± 81.5 and 360.4 ± 52.0 N, respectively, and with a bigger shift of 52.3 ± 11.9 mm and 39.4 ± 14.6 mm, respectively, compared to group 1. A critical point of failure was the anchoring in the bone. It can be concluded that the PET/PCL substitute in theex vivomodel has mechanically comparable properties with the clinically used Mersilene®,and based on its proven ability to carry stem cells it could be appropriate for partially ruptured CCL protection.

A New Equal Area Method to Calculate and Represent Physiologic, Anatomical, and Alveolar Dead Spaces

2006 ◽  
Vol 104 (4) ◽  
pp. 696-700 ◽  
Author(s):  
Yongquan Tang ◽  
Martin J. Turner ◽  
A Barry Baker
Keyword(s):  
Carbon Dioxide ◽  
Dead Space ◽  
Graphical Method ◽  
Mean Difference ◽  
Equal Area ◽  
Area Method ◽  
Physiologic Dead Space ◽  
Anatomical Dead Space ◽  
The Mean ◽  
The Difference

Background Physiologic dead space is usually estimated by the Bohr-Enghoff equation or the Fletcher method. Alveolar dead space is calculated as the difference between anatomical dead space estimated by the Fowler equal area method and physiologic dead space. This study introduces a graphical method that uses similar principles for measuring and displaying anatomical, physiologic, and alveolar dead spaces. Methods A new graphical equal area method for estimating physiologic dead space is derived. Physiologic dead spaces of 1,200 carbon dioxide expirograms obtained from 10 ventilated patients were calculated by the Bohr-Enghoff equation, the Fletcher area method, and the new graphical equal area method and were compared by Bland-Altman analysis. Dead space was varied by varying tidal volume, end-expiratory pressure, inspiratory-to-expiratory ratio, and inspiratory hold in each patient. Results The new graphical equal area method for calculating physiologic dead space is shown analytically to be identical to the Bohr-Enghoff calculation. The mean difference (limits of agreement) between the physiologic dead spaces calculated by the new equal area method and Bohr-Enghoff equation was -0.07 ml (-1.27 to 1.13 ml). The mean difference between new equal area method and the Fletcher area method was -0.09 ml (-1.52 to 1.34 ml). Conclusions The authors' equal area method for calculating, displaying, and visualizing physiologic dead space is easy to understand and yields the same results as the classic Bohr-Enghoff equation and Fletcher area method. All three dead spaces--physiologic, anatomical, and alveolar--together with their relations to expired volume, can be displayed conveniently on the x-axis of a carbon dioxide expirogram.

scholarly journals Comparison of direct and geodetic mass balances on a multi-annual time scale

2010 ◽  
Vol 4 (3) ◽  
pp. 1151-1194
Author(s):  
A. Fischer
Keyword(s):  
Mass Balance ◽  
Direct Method ◽  
Mean Difference ◽  
Published Data ◽  
Glacier Mass Balance ◽  
Mass Balances ◽  
Direct Data ◽  
The Mean ◽  
The Difference ◽  
Geodetic Mass Balance

Abstract. Glacier mass balance is measured with the direct or the geodetic method. In this study, the geodetic mass balances of six Austrian glaciers in 19 periods between 1953 and 2006 are compared to the direct mass balances in the same periods. The mean annual geodetic mass balance for all periods is −0.5 m w.e./year. The mean difference between the geodetic and the direct data is −0.7 m w.e., the minimum −7.3 m w.e. and the maximum 5.6 m w.e. The accuracy of geodetic mass balance resulting from the accuracy of the DEMs ranges from 2 m w.e. for photogrammetric data to 0.002 m w.e. for LIDAR data. Basal melt, seasonal snow cover and density changes of the surface layer contribute up to 0.7 m w.e. for the period of 10 years to the difference to the direct method. The characteristics of published data of Griesgletscher, Gulkana Glacier, Lemon Creek glacier, South Cascade, Storbreen, Storglaciären, and Zongo Glacier is similar to these Austrian glaciers. For 26 analyzed periods with an average length of 18 years the mean difference between the geodetic and the direct data is −0.4 m w.e., the minimum −7.2 m w.e. and the maximum 3.6 m w.e. Longer periods between the acquisition of the DEMs do not necessarily result in a higher accuracy of the geodetic mass balance. Specific glaciers show specific trends of the difference between the direct and the geodetic data according to their type and state. In conclusion, geodetic and direct mass balance data are complementary, but differ systematically.

scholarly journals Evaluation of Inter-System Variability in Liver Stiffness Measurements

2018 ◽  
Vol 40 (01) ◽  
pp. 64-75 ◽  
Author(s):  
Giovanna Ferraioli ◽  
Annalisa De Silvestri ◽  
Raffaella Lissandrin ◽  
Laura Maiocchi ◽  
Carmine Tinelli ◽  
...  
Keyword(s):  
Shear Wave ◽  
Liver Stiffness ◽  
Shear Wave Elastography ◽  
Mean Difference ◽  
Observer Agreement ◽  
Concordance Correlation ◽  
Limits Of Agreement ◽  
Inter Observer Variability ◽  
System Variability ◽  
The Mean

Abstract Aim The primary aim of this study was to determine the inter-system variability of liver stiffness measurements (LSMs) in patients with varying degrees of liver stiffness. The secondary aim was to determine the inter-observer variability of measurements. Materials and Methods 21 individuals affected by chronic hepatitis C and 5 healthy individuals were prospectively enrolled. The assessment of LSMs was performed using six ultrasound (US) systems, four of which with point shear wave elastography (p-SWE) and two with 2 D shear wave elastography (2D-SWE) systems. The Fibroscan (Echosens, France) was used as the reference standard. Four observers performed the measurements in pairs (A-B, C-D). The agreement between different observers or methods was calculated using Lin’s concordance correlation coefficient. The Bland-Altman limits of agreement (LOA) were calculated as well. Results There was agreement above 0.80 for all pairs of systems. The mean difference between the values of the systems with 2D-SWE technique was 1.54 kPa, whereas the maximum mean difference between the values of three out of four systems with the pSWE technique was 0.79 kPa. The intra-patient concordance for all systems was 0.89 (95 % CI: 0.83 – 0.94). Inter-observer agreement was 0.96 (95 % CI: 0.94 – 0.98) for the pair of observers A-B and 0.93 (95 % CI: 0.89 – 0.96) for the pair of observers C-D. Conclusion The results of this study show that the agreement between LSMs performed with different US systems is good to excellent and the overall inter-observer agreement in “ideal conditions” is above 0.90 in expert hands.

scholarly journals Persepsi Petani terhadap Pilihan Menjual Padi Kepada Penebas atau Perpadi (Kasus Subak Benel, Desa Kaliakah, Kecamatan Negara, Kabupaten Jembrana)

2017 ◽  
pp. 563
Author(s):  
I MADE PRASADA ARY WIRAWAN ◽  
I DEWA PUTU OKA SUARDI ◽  
I MADE SARJANA
Keyword(s):  
T Test ◽  
Mean Difference ◽  
P Value ◽  
Food Crops ◽  
Test Program ◽  
Qualitative Descriptive ◽  
The Mean ◽  
The Difference ◽  
The Government ◽  
Better Than

Farmers Perception Of Options To Sell Rice Penebas Or Perpadi(especially in Subak Benel, Kaliakah Village, Negara districts,Jembrana Regency) Various efforts have been implemented by the Provincial Food Crops Agency of Balito stabilize the price of grain, this is done by giving Funds of Rural EconomicEmpowerment Capital to the government for the purchase of rice. Although it hasbeen done from 2003, farmers are still selling it to Penebas with a bondage system.The purpose of this study to determine the perception of farmers to the choice ofselling rice to Perpadi or Penebas seen and differences in farmers' perceptions of thechoice of selling rice to Penebas or Perpadi. The research location is located in SubakBenel, Kaliakah Village, State District, Jembrana District. The analytical methodused is qualitative descriptive that aided with score, to answer the purpose ofresearch by using questionnaire. The results of this study indicate that the perceptionof farmers to the choice of selling rice to Perpadi better than to Penebas. This is seenin the achievement of the farmers' choice of selling paddy to Perpadi is very goodand to Penebas is good. The difference of Perpadi with Penebas is measured throughDifferent Test with SPSS Independent Sample T test program which the result of Sigvalue. Or p value of 0.004 where <0.05 then there is a statistically significantdifference in probability 0.05, the mean difference or mean of both groups is shownin Mean Difference ie .29559.

Biochemical Aspects and Clinical Perspectives of Continuous Urea Monitoring in Plasma Ultrafiltrate: Preliminary Results of a Multicenter Study

1995 ◽  
Vol 18 (9) ◽  
pp. 544-547 ◽  
Author(s):  
G. Colasanti ◽  
G. Arrigo ◽  
A. Santoro ◽  
S. Mandolfo ◽  
C. Tetta ◽  
...  
Keyword(s):  
Laboratory Method ◽  
Mean Difference ◽  
Limits Of Agreement ◽  
Laboratory Plasma ◽  
Plasma Urea ◽  
Urea Kinetics ◽  
On Line ◽  
The Mean ◽  
Plasma Urea Concentration

We tested a new biosensor for urea monitoring in the ultrafiltrate during PFD in a group of 5 hemodialyzed stable patients. The inspection of the UF-urea profile reflects the dynamical changes of the plasma urea concentration during diffusive dialysis and allows the fitting of the main mathematical models of urea kinetics. The biosensor efficiency was 98.4% on average (SD: 1.5%) at Uf fluxes varying from 45 to 55 ml/min (mean: 51 ml/min; SD: 3.2) and at Uf-urea concentrations varying from 23 to 165 mg/dl. The mean difference between Uf-urea determined by the laboratory method and Uf-urea assayed by the biosensor was -1.07 mg/dl and the 95% confidence interval ranged from -2.01 to 0.13 mg/dl. The mean difference between laboratory plasma urea and Uf-urea from the biosensor was on average -1.9 mg/dl and the estimated limits of agreement with a confidence of 95% were -3.16 and 0.64 mg/dl. Comparison between kinetic models and experimental profiles of plasma urea decrease, evaluations of recirculation and post-dialytic rebound, the role of Kt/V on-line during dialysis were the preliminary clinical applications of this biosensor.

Large Differences of Temperature between the Ben Nevis and Fort-William Observatories

1910 ◽  
Vol 44 (2) ◽  
pp. 702-705
Author(s):  
R. T. Omond
Keyword(s):  
Preceding Paper ◽  
Mean Difference ◽  
Average Difference ◽  
The Mean ◽  
The Difference

The immediately preceding paper deals with the average difference of temperature between Ben Nevis and Fort-William throughout the year, but the difference often departs widely from these average values. The greatest departures from the average during the time that hourly readings are available at both places, viz. from 1st August 1890 to 30th September 1904, were Ben Nevis 17°·6 warmer than Fort-William at 9 A.M. on 19th February 1895, and Ben Nevis 28°·8 colder than Fort-William at 2 A.M. on 19th December 1890, being respectively 33°·3 below and 13°·1 above the mean difference, which is Ben Nevis 15°·7 colder than Fort-William.

Effect of Tibial Plateau Levelling Osteotomy on Cranial Tibial Subluxation in the Feline Cranial Cruciate Deficient Stifle Joint: An Ex Vivo Experimental Study

2018 ◽  
Vol 31 (04) ◽  
pp. 273-278
Author(s):  
A. Bilmont ◽  
M. Retournard ◽  
E. Asimus ◽  
S. Palierne ◽  
A. Autefage
Keyword(s):  
Tibial Plateau ◽  
Rotation Angle ◽  
Ex Vivo ◽  
Cruciate Ligament ◽  
Tibial Rotation ◽  
Cranial Cruciate Ligament ◽  
Stifle Joint ◽  
Before And After ◽  
Osteotomy Technique ◽  
Gastrocnemius Muscles

Objectives This study evaluated the effects of tibial plateau levelling osteotomy on cranial tibial subluxation and tibial rotation angle in a model of feline cranial cruciate ligament deficient stifle joint. Methods Quadriceps and gastrocnemius muscles were simulated with cables, turnbuckles and a spring in an ex vivo limb model. Cranial tibial subluxation and tibial rotation angle were measured radiographically before and after cranial cruciate ligament section, and after tibial plateau levelling osteotomy, at postoperative tibial plateau angles of +5°, 0° and –5°. Results Cranial tibial subluxation and tibial rotation angle were not significantly altered after tibial plateau levelling osteotomy with a tibial plateau angle of +5°. Additional rotation of the tibial plateau to a tibial plateau angle of 0° and –5° had no significant effect on cranial tibial subluxation and tibial rotation angle, although 2 out of 10 specimens were stabilized by a postoperative tibial plateau angle of –5°. No stabilization of the cranial cruciate ligament deficient stifle was observed in this model of the feline stifle, after tibial plateau levelling osteotomy. Clinical Significance Given that stabilization of the cranial cruciate ligament deficient stifle was not obtained in this model, simple transposition of the tibial plateau levelling osteotomy technique from the dog to the cat may not be appropriate.

Modelling the Effects of Cranial Cruciate Ligament Transection, Medial Meniscal Release and Triple Tibial Osteotomy on Stability of the Canine Stifle Joint

2020 ◽  
Vol 33 (03) ◽  
pp. 174-182
Author(s):  
Tanja V. Jensen ◽  
Signe S. Kristiansen ◽  
Lene E. Buelund ◽  
James E. Miles
Keyword(s):  
Ex Vivo ◽  
Cruciate Ligament ◽  
Patellar Ligament ◽  
Tibial Osteotomy ◽  
Joint Angles ◽  
Cranial Cruciate Ligament ◽  
Stifle Joint ◽  
Wide Range ◽  
Loading Ratio ◽  
Canine Stifle

Abstract Objective The aim of this study was to evaluate the ex vivo effects of sequential cranial cruciate ligament transection (CCLx), medial meniscal release (MMR) and triple tibial osteotomy (TTO) on canine stifle stability compared with the intact state, across a wide range of joint angles. Study Design Nine right hind limb preparations were instrumented to provide constant quadriceps and gastrocnemius loads in a 3:1 ratio, and extended from full flexion during fluoroscopic recording. Recordings were repeated after each of CCLx, MMR and TTO. Fluoroscopic landmarks were used to calculate tibial subluxation and patellar ligament angle. Results Medial meniscal release resulted in additional cranial tibial subluxation compared with CCLx. Triple tibial osteotomy restored stifle stability up to a joint angle of 125 degrees. The presence of the crossover angle could be inferred from the patellar ligament angle and subluxation curves. Conclusion Our results suggest that in the cranial cruciate ligament-deficient stifle, the crossover angle at which loading shifts between the caudal and cranial cruciate ligaments is dependent on both loading and integrity of the medial meniscus. Triple tibial osteotomy improves stifle stability over a wide range of joint angles under a quadricep to gastrocnemius loading ratio of 3:1 by converting cranial tibial thrust to caudal tibial thrust, due to TTO increasing the amount of joint extension required to reach the crossover angle.

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