scholarly journals Does Cement Augmentation of the Sacroiliac Screw Lead to Superior Biomechanical Results for Fixation of the Posterior Pelvic Ring? A Biomechanical Study

Medicina ◽  
2021 ◽  
Vol 57 (12) ◽  
pp. 1368
Author(s):  
Moritz F. Lodde ◽  
J. Christoph Katthagen ◽  
Clemens O. Schopper ◽  
Ivan Zderic ◽  
R. Geoff Richards ◽  
...  

Background and Objectives: The stability of the pelvic ring mainly depends on the integrity of its posterior part. Percutaneous sacroiliac (SI) screws are widely implanted as standard of care treatment. The main risk factors for their fixation failure are related to vertical shear or transforaminal sacral fractures. The aim of this study was to compare the biomechanical performance of fixations using one (Group 1) or two (Group 2) standard SI screws versus one SI screw with bone cement augmentation (Group 3). Materials and Methods: Unstable fractures of the pelvic ring (AO/OTA 61-C1.3, FFP IIc) were simulated in 21 artificial pelvises by means of vertical osteotomies in the ipsilateral anterior and posterior pelvic ring. A supra-acetabular external fixator was applied to address the anterior fracture. All specimens were tested under progressively increasing cyclic loading until failure, with monitoring by means of motion tracking. Fracture site displacement and cycles to failure were evaluated. Results: Fracture displacement after 500 cycles was lowest in Group 3 (0.76 cm [0.30] (median [interquartile range, IQR])) followed by Group 1 (1.42 cm, [0.21]) and Group 2 (1.42 cm [1.66]), with significant differences between Groups 1 and 3, p = 0.04. Fracture displacement after 1000 cycles was significantly lower in Group 3 (1.15 cm [0.37]) compared to both Group 1 (2.19 cm [2.39]) and Group 2 (2.23 cm [3.65]), p ≤ 0.04. Cycles to failure (Group 1: 3930 ± 890 (mean ± standard deviation), Group 2: 3676 ± 348, Group 3: 3764 ± 645) did not differ significantly between the groups, p = 0.79. Conclusions: In our biomechanical setup cement augmentation of one SI screw resulted in significantly less displacement compared to the use of one or two SI screws. However, the number of cycles to failure was not significantly different between the groups. Cement augmentation of one SI screw seems to be a useful treatment option for posterior pelvic ring fixation, especially in osteoporotic bone.

2004 ◽  
Vol 101 (2) ◽  
pp. 445-450 ◽  
Author(s):  
Lukas Kirchmair ◽  
Birgit Enna ◽  
Gottfried Mitterschiffthaler ◽  
Bernhard Moriggl ◽  
Manfred Greher ◽  
...  

Background Pediatric regional anesthesia has gained increasing interest over the past decades. The current study was conducted to investigate the lumbar paravertebral region and the lumbar plexus at L3-L4 and L4-L5 by means of sonography to obtain fundamentals for the performance of ultrasound-guided posterior lumbar plexus blocks. Methods Thirty-two children (12 boys, 20 girls) with American Society of Anesthesiologists physical status I or II were enrolled in the current study. The lumbar paravertebral region was visualized at L3-L4 and L4-L5 on two corresponding posterior sonograms (longitudinal, transverse). The lumbar plexus had to be delineated, and skin-plexus distances were measured. In a series of five pediatric patients undergoing inguinal herniotomy, ultrasound-guided posterior lumbar plexus blocks at L4-L5 were performed. Results The children were stratified into three age groups (group 1: > 3 yr and </= 5 yr; group 2: > 5 yr and </= 8 yr; group 3: > 8 yr and </= 12 yr). The lumbar plexus could be delineated at L3-L4 and L4-L5 in 19 of 20 cases in group 1, in 17 of 20 cases in group 2, in 22 of 24 cases at L3-L4 in group 3, and in 16 of 24 cases at L4-L5 in group 3. In all patients, the lumbar plexus was situated within the posterior part of the psoas major muscle. Skin-plexus distances showed statistical significant differences between groups 1 and 3 and between groups 2 and 3. The strongest positive correlation existed between skin-plexus distances and the children's weight. Ultrasound guidance enabled safe und successful posterior approaches to the lumbar plexus, thus resulting in effective anesthesia and analgesia of the inguinal region. Conclusions Sonography of the lumbar plexus in children proved to be feasible. Skin-plexus distances correlated with the children's weight rather than with their age. The sonographic findings were fundamental for the performance of successful ultrasound-guided posterior approaches in a small group of pediatric patients.


2021 ◽  
Vol 29 (3) ◽  
pp. 397-409
Author(s):  
Anton N. Kazantsev ◽  
Konstantin P. Chernykh ◽  
Roman A. Vinogradov ◽  
Mikhail A. Chernyavskiy ◽  
Vyacheslav N. Kravchuk ◽  
...  

BACKGROUND: The circle of Willis (CW) is an important network of collaterals that provide compensatory redistribution of hemodynamic load. Several studies showed that the CW is open in approximately 50%90% of cases, and the number of missing segments correlates with low brain tolerance to ischemia in internal carotid artery (ICA) compression. Currently, studies dedicated to the relationship of different configurations of CW with the risk of ischemic brain damage. AIM: The analyze the immediate results of eversion carotid endarterectomy (CEA) in patients with different configurations of the structure of the CW. MATERIALS AND METHODS: We included 641 patients with hemodynamically significant stenosis of the internal carotid arteries (ICA) in a study period from 2010 to 2020. All patients underwent multispiral computed tomography with angiography of the extracranial and CW arteries. Based on the structural variants of the CW, six groups of patients were studied: group 1 (64.9%, n = 416) closed posterior part (CPP) with the existence of posterior communicative artery (PCA) and P1 segment of the posterior cerebral artery (PCerA); group 2 (27%, n = 173) an intermediate structure of the posterior part (IPP) with hypoplasia of the PCA or PCerA; group 3 (8.1%, n = 52) open posterior part (OPP) with the absence of PCA or PCerA; group 4 (85.95%, n = 551) closed anterior part (CAP) with the presence of the anterior communicating artery (ACA) and A1 segment of the anterior cerebral artery (ACerA); group 5 (7.95%, n = 51) an intermediate structure of the anterior part (IAP) with hypoplasia of ACA or ACerA; group 6 (6.1%, n = 39) open anterior part (OAP) with the absence of ACA or ACerA. To assess the compensatory potentials of the brain, all patients underwent measurement of the retrograde pressure in the ICA and intraoperative cerebral oximetry. RESULTS: In the postoperative period, 1 death was recorded in group 4 (CAP) due to a hemorrhagic transformation in the zone of ischemic stroke, on the background development of hyperperfusion syndrome. The largest number of ischemic strokes of the cardioembolic subtype was diagnosed in the ACerA territory in the presence of an unstable atherosclerotic plaque: group 1 (CPP) 0%; group 2 (IPP) 0%; group 3 (OPP) 0.24%, n = 1; group 4 (CAP) 0.18%, n = 1; group 5 (IAP) 1.96%, n = 1; group 6 (OAP) 5.1%, n = 2; p 0.9999. The probable cause was embolization against the background increase in the arterial pressure before ICA clamping. In turn, the majority of ischemic strokes of the hemodynamic subtype developed in the territory of PCerA: group 1 (CPP) 0%; group 2 (IPP) 1.73%, n = 3; group 3 (OPP) 3.8%, n = 2; group 4 (CAP) 0.18%, n = 1; group 5 (IAP) 0%; group 6 (OAP) 2.56%, n = 1; p 0.9999. This pattern coincided with the largest number of patients with CW of the IPP and OPP types among all open variants of the structure. CONCLUSION: Parameters of retrograde pressure in the ICA and intraoperative cerebral oximetry do not always demonstrate the need for a temporary shunt (TS). Due to the opened structure of CW, the redistribution of blood flow occurs with the formation of zones of hypo- and hyperperfusion, causing ischemic alterations in the brain matter. Thus, in order to maintain adequate cerebral hemodynamics, to mitigate the effect of hypo- and hyperperfusion, and reduce the risk of ischemic stroke, the open variant of the CW structure should be considered as an indication for a TS.


VASA ◽  
2020 ◽  
Vol 49 (4) ◽  
pp. 281-284
Author(s):  
Atıf Yolgosteren ◽  
Gencehan Kumtepe ◽  
Melda Payaslioglu ◽  
Cuneyt Ozakin

Summary. Background: Prosthetic vascular graft infection (PVGI) is a complication with high mortality. Cyanoacrylate (CA) is an adhesive which has been used in a number of surgical procedures. In this in-vivo study, we aimed to evaluate the relationship between PVGI and CA. Materials and methods: Thirty-two rats were equally divided into four groups. Pouch was formed on back of rats until deep fascia. In group 1, vascular graft with polyethyleneterephthalate (PET) was placed into pouch. In group 2, MRSA strain with a density of 1 ml 0.5 MacFarland was injected into pouch. In group 3, 1 cm 2 vascular graft with PET piece was placed into pouch and MRSA strain with a density of 1 ml 0.5 MacFarland was injected. In group 4, 1 cm 2 vascular graft with PET piece impregnated with N-butyl cyanoacrylate-based adhesive was placed and MRSA strain with a density of 1 ml 0.5 MacFarland was injected. All rats were scarified in 96th hour, culture samples were taken where intervention was performed and were evaluated microbiologically. Bacteria reproducing in each group were numerically evaluated based on colony-forming unit (CFU/ml) and compared by taking their average. Results: MRSA reproduction of 0 CFU/ml in group 1, of 1410 CFU/ml in group 2, of 180 200 CFU/ml in group 3 and of 625 300 CFU/ml in group 4 was present. A statistically significant difference was present between group 1 and group 4 (p < 0.01), between group 2 and group 4 (p < 0.01), between group 3 and group 4 (p < 0.05). In terms of reproduction, no statistically significant difference was found in group 1, group 2, group 3 in themselves. Conclusions: We observed that the rate of infection increased in the cyanoacyrylate group where cyanoacrylate was used. We think that surgeon should be more careful in using CA in vascular surgery.


1984 ◽  
Vol 52 (03) ◽  
pp. 253-255 ◽  
Author(s):  
C Isles ◽  
G D O Lowe ◽  
B M Rankin ◽  
C D Forbes ◽  
N Lucie ◽  
...  

SummaryWe have previously shown abnormalities of haemostasis suggestive of intravascular coagulation in patients with malignant hypertension, a condition associated with retinopathy and renal fibrin deposition. To determine whether such abnormalities are specific to malignant hypertension, we have measured several haemostatic and haemorheological variables in 18 patients with malignant hypertension (Group 1), 18 matched healthy controls (Group 2), and 18 patients with non-malignant hypertension (Group 3) matched for renal pathology, blood pressure and serum creatinine with Group 1. Both Groups 1 and 3 had increased mean levels of fibrinogen, factor VIIIc, beta-thrombo- globulin, plasma viscosity and blood viscosity (corrected for haematocrit); and decreased mean levels of haematocrit, antithrombin III and platelet count. Mean levels of fast antiplasmin and alpha2-macroglobulin were elevated in Group 1 but not in Group 3. We conclude that most blood abnormalities are not specific to malignant hypertension; are also present in patients with non-malignant hypertension who have similar levels of blood pressure and renal damage; and might result from renal damage as well as promoting further renal damage by enhancing fibrin deposition. However increased levels of fibrinolytic inhibitors in malignant hypertension merit further investigation in relation to removal of renal fibrin.


2020 ◽  
pp. 64-75
Author(s):  
E. Burleva ◽  
O. Smirnov ◽  
S. Tyurin

The purpose of the study was to conduct a comparative assessment of the course of the postoperative period after phlebectomy and thermal ablation in patients with varicose veins of the lower extremities in the system of the great saphenous vein (GSV) with class C2 of chronic venous insufficiency (CVI) — CEAP class C2. Materials and methods: 455 patients (455 limbs) with CEAP class C2. Group 1 (n = 154) received stripping + minimally invasive phlebectomy; Group 2 — endovenous laser ablation (EVLA) of GSV trunk + sclerotherapy of varicose veins; 3 group (n = 150) — radiofrequency ablation (RFA) of the GSV + sclerotherapy. All patients were united by a single tactical solution — the elimination of pathological vertical reflux in GSV. In each group, patients were with similar hemodynamic profile were selected (Group 1 = 63; Group 2 = 61; Group 3 = 61). The course of the postoperative period (from 2 days to 2 months) was compared for pain (visual analog scale — VAS), clinical symptoms of chronic venous insufficiency, degree of satisfaction (Darvall questionnaire), and duration of disability. Statistical processing was carried out using Excel programs for Windows XP, MedCalc® (version 11.4.2.0., Mariakerke, Belgium). Results: Postoperative pain is more pronounced (during day 1 for Group 1–4.0, Group 2–3.0, Group 3–2.0) and more prolonged (up to 4 days) after open surgeries (p < 0.05). The dynamics of the clinical symptoms of CVI (including varicose syndrome and use of compression therapy) could not be fully evaluated in connection with the ongoing sclerotherapy procedures for patients of Groups 2 and 3. Satisfaction of patients with aesthetic aspects was higher than expected in all groups. Reliable statistical differences proved decrease in days of disability (Group 1–14; Group 2–4; Group 3–3) and earlier return to physical activities and work in patients after thermal ablation in comparison with phlebectomy. Conclusion: The study shows that all three methods for eliminating vertical reflux in the GSV can be proposed for a large category of patients with CEAP of class C3 and C2. Medical and social rehabilitation of patients using endovascular thermal ablation technologies proceeds faster, which is beneficial both for the patients and for society.


To identify the prevalence of early pathology of cardiovascular diseases, a survey of 400 200 girls) in the age group 15 and 17 years old was conducted as a part of routine medical of the level of blood pressure (BP) was carried out, with the calculation of the average level pressure on the basis of three separate measurements estimated by percentile tables for a registration of a standard resting ECG in 12 leads. According to the results of the survey, into 3 groups: with an increase in blood pressure above 95 ‰ (group 1 – 16 people), which recorded in males (p<0,05); Group 2 (67 people) – adolescents with a normal blood pressure level and group 3 of adolescents with a decrease in blood pressure below 5 ‰ changes in the form of rhythm and conduction disturbances were noted in almost every a predominance of sinus tachycardia in the first group. In the third group of adolescents, form of ectopic rhythm and pacemaker migration were significantly more frequently only 78 % of adolescents were referred for consultation and in-depth examination by a pediatric cardiologist.


2019 ◽  
Vol 17 (4) ◽  
pp. 354-364
Author(s):  
Hassan Al-Thani ◽  
Moamena El-Matbouly ◽  
Maryam Al-Sulaiti ◽  
Noora Al-Thani ◽  
Mohammad Asim ◽  
...  

Background: We hypothesized that perioperative HbA1c influenced the pattern and outcomes of Lower Extremity Amputation (LEA). Methods: A retrospective analysis was conducted for all patients who underwent LEA between 2000 and 2013. Patients were categorized into 5 groups according to their perioperative HbA1c values [Group 1 (<6.5%), Group 2 (6.5-7.4%), Group 3 (7.5-8.4%), Group 4 (8.5-9.4%) and Group 5 (≥9.5%)]. We identified 848 patients with LEA; perioperative HbA1c levels were available in 547 cases (Group 1: 18.8%, Group 2: 17.7%, Group 3: 15.0%, Group 4: 13.5% and Group 5: 34.9%). Major amputation was performed in 35%, 32%, 22%, 10.8% and 13.6%, respectively. Results: The overall mortality was 36.5%; of that one quarter occurred during the index hospitalization. Mortality was higher in Group 1 (57.4%) compared with Groups 2-5 (46.9%, 38.3%, 36.1% and 31.2%, respectively, p=0.001). Cox regression analysis showed that poor glycemic control (Group 4 and 5) had lower risk of mortality post-LEA [hazard ratio 0.57 (95% CI 0.35-0.93) and hazard ratio 0.46 (95% CI 0.31-0.69)]; this mortality risk persisted even after adjustment for age and sex but was statistically insignificant. The rate of LEA was greater among poor glycemic control patients; however, the mortality was higher among patients with tight control. Conclusion: The effects of HbA1c on the immediate and long-term LEA outcomes and its therapeutic implications need further investigation.


2018 ◽  
Vol 46 (1) ◽  
Author(s):  
Ricardo Christ ◽  
Aleksandro Schafer Da Silva ◽  
Mateus Eloir Grabriel ◽  
Luan Cleber Henker ◽  
Renan Augusto Cechin ◽  
...  

  Background: Nitrate and nitrite poisoning is associated with pasture intake that has high nitrate levels and leads to acute methemoglobinemia. Pasture may accumulate nitrate under certain conditions, such as excessively fertilized soil or en­vironmental conditions that enhance the N absorption (rain preceded by a period of drought). After ingestion of plants, this substrate reaches the rumen and, in physiological conditions, is reduced to nitrite and afterward to ammonia. The aim of this study was to evaluate changes in cholinesterase activities and oxidative stress caused by subclinical poisoning for nitrate and nitrite in cattle fed with Pennisetum glaucum in three different fertilization schemes. Materials, Methods & Results: In order to perform the experimental poisoning, the pasture was cultivated in three dif­ferent paddocks: with nitrogen topdressing (urea; group 1), organic fertilizer (group 2) or without fertilizer (group 3; control). Nitrate accumulation in forage was evaluated by the diphenylamine test. After food fasting of 12 h, nine bovine were randomly allocated to one of the experimental groups and fed with fresh forage (ad libitum) from respective pad­dock. In different time points from beginning of pasture intake (0, 2, 4, 6 and 9 h) heart rate and respiratory frequency were assessed, as well as mucous membrane color and behavioral changes. Blood samples from jugular vein into vials with and without anticoagulant were collected. From blood samples, serum nitrite levels, acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) enzyme activity were evaluated, as well as oxidative stress through the following param­eters: levels of nitrate/nitrite (NOx), thiobarbituric acid reactive substances (TBARS) and reactive oxygen species (ROS), beyond the antioxidant system by enzyme activity measurement of catalase (CAT) and superoxide dismutase (SOD). The diphenylamine test was positive to group 1 and 2, so that the pasture presented 3.16 mg/kg, 2.98 mg/kg and 1.67 mg/kg of nitrate for group 1, 2 and 3, respectively. In addition, cows from group 1 demonstrated increased (P < 0.05) nitrite levels in serum, compared to other groups, and greater heart rate after 9 h (P < 0.05). The AChE and BChE activity in group 1 showed significant increase (P < 0.05) at 4 and 6 h (AChE), and 4 and 9 h (BChE) compared to group 3. Also, NOx levels were lower at 6 and 9 h (P < 0.05) and at 9 h (P < 0.05) for animals of group 1 and 2, respectively, when compared to group 3. Furthermore, in the group 1 levels of ROS and TBARS were significantly higher (P < 0.05) after 2 and 4 h, and 6 and 9 h compared to other groups, respectively. The CAT activity increased significantly (P < 0.05) with 2 and 4 h of the experiment, but on the other hand, decreased at 6 and 9 h in group 1. Nevertheless, the animals from group 2 presented only a significant reduction in this enzyme activity at 9 h. Furthermore, SOD activity was reduced in animals of groups 1 (P < 0.05) at 4, 6 and 9 h, compared to other groups. Discussion: It was concluded that the nitrate and nitrite poisoning by pasture intake cultivated and fertilized with urea leads to increased levels of serum nitrite, as well as the cholinesterase activity and causes oxidative stress in cattle. It is conjectured that the cholinesterase activity and oxidative stress may assist in understanding the pathophysiology of changes caused by poisoning.Keywords: plant toxicology, poisoning, methemoglobin, cholinergic system, oxidative stress.


2021 ◽  
Vol 28 (3) ◽  
pp. 328-338
Author(s):  
Ogbutor Udoji Godsday ◽  
Nwangwa Eze Kingsley ◽  
Nwogueze Bartholomew Chukwuebuka ◽  
Chukwuemeka Ephraim ◽  
Ezunu Emmanuel ◽  
...  

Decline in normal physiological pulmonary function has been attributed to premorbid conditions such as prehypertension. Research evidence suggests that physical activity reduces age-related decline in pulmonary function and improves the efficiency of the lungs in prehypertensive patients. However, there is a scarcity of data evidence relating to isometric exercise and pulmonary function. Furthermore, the interrelationship between the intensity and duration of isometric exercise and pulmonary function in these patients is still uncertain. Therefore, this study was undertaken to investigate the effect of isometric handgrip exercise on pulmonary function capacity in adults with prehypertension. To determine the effectiveness of isometric handgrip exercise on pulmonary function capacity in adults with prehypertension. A quasi experiment using a pre- and post-exercise method was carried out in two out-patients hospital settings. The sample comprised 192 sedentary pre-hypertensive subjects, aged between 30–50 years, that were randomly distributed into three groups of 64 participants each. The subjects performed, for 24 consecutive days, an isometric handgrip exercise at 30% Maximum Voluntary Contraction (M.V.C.). At the end of the 24 days, group one (GP1) discontinued, while group two (GP2) continued the exercise protocol for another 24 consecutive days and group three (GP3) continued with the exercise protocol for another 24 consecutive days but at 50% M.V.C. Determinants of lung function (outcomes) were Forced Expiratory Volume in 1 s (FEV1), Forced Vital Capacity (FVC), FEV1/FVC Ratio and Peak Expiratory Flow Rate (PEFR). The study shows that there was no statistically significant difference in the pre- and post-exercise outcomes for FEV1, FVC, FEV1/FVC Ratio and PEFR after 24 days for group 1. In group 2, there was a statistically significant difference in the FVC [(mean = 0.12 ± 0.12), (p = 0.002)], FEV1 [(mean = 0.15 ± 0.17), (p = 0.003)] and PEF [(mean = 0.85 ± 0.35), (p = 0.001)] after 48 days. In group 3, there was a statistically significant difference (p = 0.001) in all the outcomes assessed after 48 days. There was a between groups difference in favour of group 2 compared with group 1 for outcomes of FEV1 [(mean = 0.142 ± 0.68), (p = 0.005)] and PEF [(mean = 0.83 ± 0.19), (p = 0.0031)]. There was statistically significant difference in favour of group 3 compared to group 2, by increasing the exercise intensity from 30% to 50% M.V.C., for outcomes of FVC [mean change = 0.10 ± 0.052), (p = 0.005)], FEV1/FVC [mean change = 3.18 ± 0.75), (p = 0.017)] and PEF [(mean change = 0.86 ± 0.35), (p = 0.001)] after 48 days. Isometric handgrip exercise (after 48 days at 30% to 50% M.V.C.) improves outcomes of pulmonary function capacity in adults with prehypertension. Meanwhile, duration and/or increase in intensity of the isometric effort significantly contributed to the affects attained.


2021 ◽  
pp. 112067212199295
Author(s):  
Gurkan Erdogan ◽  
Nilay Kandemir Besek ◽  
Betul Onal Gunay ◽  
Alper Agca

Objective: To investigate the clinical outcomes of three surgical approaches for ectopia lentis in Marfan syndrome (MS) patients who had undergone crystalline lens removal with posterior chamber intraocular lens (IOL) implantation techniques comprising the intrascleral fixation of IOL, sutured scleral fixation of IOL, and IOL implantation with the use of a Cionni capsular tension ring (CTR). Methods: This is a retrospective comparative study, including 35 eyes of 21 patients who underwent the intrascleral fixation of IOL (group 1), scleral IOL fixation with the Z-suture (group 2), and IOL implantation with the use of a Cionni CTR (group 3) following crystalline lens removal. The surgical indications were as follows: no improvement in visual function after eyeglasses or contact lens application due to excessive irregular astigmatism and advanced crystalline lens decentration in which the edge of the crystalline lens came up to the optical axis, or dislocation of the crystalline lens resulting in aphakia and secondary glaucoma due to lens dislocation. The surgical outcomes and complications due to surgery were compared between the groups. Results: The mean age of the patients in the study was 12.3 ± 8.7 years (5–32 years). There were 10 eyes in group 1, 13 eyes in group 2, and 12 eyes in group 3. Visual acuity improved significantly in each group after surgery. Ocular residual astigmatism did not differ significantly between the groups ( p = 0.51). Conclusion: There were no significant differences between the three surgical approaches in the current study in terms of the postoperative results and complications.


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