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71.
BackgroundReverse total shoulder arthroplasty (RSA) primarily varies between 2 implant design options: a 135 humeral stem inclination that closely resembles anatomic orientation, versus the Grammont-style 155 humeral stem inclination that further medializes and distalizes the center of rotation (COR). The purpose of this study was to compare deltoid force, glenoid strain, and simulated glenohumeral range of motion (ROM) between RSA 135 and RSA 155 designs, with a series of standardized permutations of glenosphere offset and rotator cuff pathology.MethodsTwelve fresh-frozen cadaveric shoulder specimens were studied using a shoulder simulator. Native shoulder motion profiles for reproducible abduction range of motion were established using a customized testing device. Optical 3-dimensional tracking and pressure sensors were used to accurately record glenohumeral range of motion (ROM), deltoid force, and glenoid strain for RSA 135 and RSA 155 designs. For each cohort, all combinations of glenosphere offsets and rotator cuff tendon involvement were evaluated.ResultsThere was no significant difference in the overall abduction ROM between the 155 and the 135 humeral stem implants (P = .75). Resting abduction angle and maximum abduction angle were significantly greater with a 155 + STD (standard offset) construct than with a 135 + STD construct (P < .001 and P = .01, respectively). Both stem inclinations decreased combined deltoid force requirements as compared the native shoulder with a massive cuff tear. Effective glenoid strain did not vary significantly between 135 + STD and 155 + STD constructs (P = .66).ConclusionOverall, range of motion between the 135 and the 155 humeral stem inclinations was not significantly different. The cumulative deltoid force was lower in RSA shoulders when compared to native shoulders with massive rotator cuff tears, highlighting the utility of both implant designs. The Grammont-style 155 stem coupled with a 2.5 mm inferior offset glenosphere required less deltoid force to reach maximum abduction than did the more anatomic, lateralized 135 stem coupled with a 4 mm lateral offset glenosphere.Level of EvidenceBasic Science, Biomechanics Controlled Laboratory Study  相似文献   
72.
BackgroundThe purpose of this study is to determine the comparative risk profile and clinical outcomes for patients undergoing reverse total shoulder arthroplasty (RTSA) for cuff tear arthropathy (CTA) without failed prior rotator cuff repair (RCR) compared with RTSA for CTA with prior RCR.MethodsFrom 2006 to 2014, all patients who underwent RTSA by two surgeons after failed RCR with minimum 2-year follow-up were identified. Patients who underwent RTSA with failed prior RCR were matched in a 1:1 ratio to patients undergoing primary RTSA, while controlling for demographic factors, prosthesis design, and surgeon. Postoperative active forward elevation and active external rotation were recorded. Outcome measures included American Shoulder and Elbow Surgeons score, Visual Analog Scale (VAS), and Simple Shoulder Test. Perioperative complications and rates of secondary reoperation were noted, and comparative multivariate analysis was performed.ResultsOf 262 patients, 192 (73.3%) were available at minimum 2-year follow-up. The prior RCR group had a significantly higher complication rate (17.4%, n = 15) than the primary RTSA group (3.8%, n = 4) (P = .001), although no significant difference in periprosthetic infection (P = .469) or secondary revision rate (P = .136) was observed. At mean 36.3 ± 26.1-month follow-up, the prior RCR group had statistically worse American Shoulder and Elbow Surgeons score (P < .001), VAS (P = .001), Simple Shoulder Test (P < .001), and active forward elevation (P = .006). Patients with multiple failed RCR attempts (n = 38) before RTSA demonstrated no significant differences versus isolated failed RCR (n = 48; P > .05).ConclusionThis study demonstrated that patients with RTSA after prior failed RCR have significantly worse patient-reported outcomes and greater rate of perioperative complications than patients undergoing primary RTSA for CTA.  相似文献   
73.
World Journal of Surgery - The Global Initiative for Children's Surgery (GICS) group produced the Optimal Resources for Children’s Surgery (OReCS) document in 2019, listing standards of...  相似文献   
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76.
The authors hypothesized that age, body mass index (BMI), and medical comorbidities (graded with the Charleson Comorbidiy index [CCI]) could be used to predict early complications after TSA. The authors performed a retrospective review of primary TSAs with a minimum of 90-day follow-up. One hundred twenty-seven patients met the inclusion criteria. Complications occurred in 12 (9.4%) of patients. Major complications occurred in 1 patient (0.8%), medical in 8 (6.3%), and surgical in 4 (3.1%). CCI significantly correlated with complication rates and multivariate regression analysis demonstrated CCI to be the only significant determinant of overall complication rates (P = 0.005) and medical complication rates (P = 0.015). While BMI subgroup did not affect complication rates, transfusion rates, intra-operative blood loss, or operative time, our study may have been underpowered for this variable.  相似文献   
77.

Introduction

Laparoscopic Heller-Dor surgery is the current treatment of choice for patients with esophageal achalasia, but elderly patients are generally referred for less invasive treatments (pneumatic dilations or botulinum toxin injections).

Aim

To assess the effect of age on the surgical outcome of patients receiving laparoscopic Heller-Dor as primary treatment.

Methods

Demographic and clinical findings were prospectively collected on patients undergoing laparoscopic Heller-Dor from 1992 to 2012. Patients were classified in three age brackets: group A (≤45 years), group B (45–70), and group C (≥70). Treatment was defined as a failure if the postoperative symptom score was >10th percentile of the preoperative score (i.e., >8). We consecutively performed the Heller-Dor in 571 achalasia patients, 305 (53.4 %) in group A, 226 (39.6 %) in group B, and 40 (7 %) in group C.

Results

The mortality was nil; the conversion and morbidity rates were both 1.1 %. Group C patients had higher preoperative symptom scores (p?=?0.02), while the symptom duration was similar in all three groups. Mucosal tears occurred in 17 patients (3 %): 6 (2 %) in group A, 8 (3.5 %) in group B, and 3 (7.5 %) in group C (p?=?0.09). The postoperative hospital stay was slightly longer for group C (p?=?0.06).

Discussion

The treatment failure rate was quite similar: 31 failures in group A (10.1 %), 19 in group B (8.4 %), and 3 in group C (7.5 %; p?=?0.80). These failures were seen more in manometric pattern III (22.2 %, p?=?0.002). Laparoscopic Heller-Dor can be used as the first therapeutic approach to achalasia even in elderly patients with an acceptable surgical risk.  相似文献   
78.
BackgroundIt is unclear whether patients with inflammatory bowel disease (IBD) are at increased risk of COVID-19.ObjectivesThis observational study compared the prevalence of COVID-19 symptoms, diagnosis and hospitalization in IBD patients with a control population with non-inflammatory bowel disorders.MethodsThis multicentre study, included 2733 outpatients (1397 IBD patients and 1336 controls), from eight major gastrointestinal centres in Lombardy, Italy. Patients were invited to complete a web-based questionnaire regarding demographic, historical and clinical features over the previous 6 weeks. The prevalence of COVID-19 symptoms, diagnosis and hospitalization for COVID-19 was assessed.Results1810 patients (64%) responded to the questionnaire (941 IBD patients and 869 controls). IBD patients were significantly younger and of male sex than controls. NSAID use and smoking were more frequent in controls. IBD patients were more likely treated with vitamin-D and vaccinated for influenza. Highly probable COVID-19 on the basis of symptoms and signs was less frequent in the IBD group (3.8% vs 6.3%; OR:0.45, 95%CI:0.28–0.75). IBD patients had a lower rate of nasopharyngeal swab-PCR confirmed diagnosis (0.2% vs 1.2%; OR:0.14, 95%CI:0.03–0.67). There was no difference in hospitalization between the groups (0.1% vs 0.6%; OR:0.14, 95%CI:0.02–1.17).ConclusionIBD patients do not have an increased risk of COVID-19 specific symptoms or more severe disease compared with a control group of gastroenterology patients.  相似文献   
79.
Many different osteotomy procedures has been proposed in the literature for dental implant site preparation. The osseodensification is a drilling technique that has been proposed to improve the local bone quality and implant stability in poor density alveolar ridges. This technique determines an expansion of the implant site by increasing the density of the adjacent bone. The aim of the present investigation was to evaluate the effectiveness of the osseodensification technique for implant site preparation through a literature review and meta-analysis. The database electronic research was performed on PubMed (Medline) database for the screening of the scientific papers. A total of 16 articles have been identified suitable for the review and qualitative analysis—11 clinical studies (eight on animals, three on human subjects), four literature reviews, and one case report. The meta-analysis was performed to compare the bone-to-implant contact % (BIC), bone area fraction occupied % (BAFO), and insertion torque of clockwise and counter-clockwise osseodensification procedure in animal studies. The included articles reported a significant increase in the insertion torque of the implants positioned through the osseodensification protocol compared to the conventional drilling technique. Advantages of this new technique are important above all when the patient has a strong missing and/or low quantity of bone tissue. The data collected until the drafting of this paper detect an improvement when the osseodensification has been adopted if compared to the conventional technique. A significant difference in BIC and insertion torque between the clockwise and counter-clockwise osseodensification procedure was reported, with no difference in BAFO measurements between the two approaches. The effectiveness of the present study demonstrated that the osseodensification drilling protocol is a useful technique to obtain increased implant insertion torque and bone to implant contact (BIC) in vivo. Further randomized clinical studies are required to confirm these pieces of evidence in human studies.  相似文献   
80.
Romeo  V.  Sarno  L.  Volpe  A.  Ginocchio  M. I.  Esposito  R.  Mainenti  P. P.  Petretta  M.  Liuzzi  R.  D’Armiento  M.  Martinelli  P.  Brunetti  A.  Maurea  S. 《Abdominal imaging》2019,44(10):3398-3407
Purpose

To compare the performance US and MR in identifying placental adhesion spectrum (PAS) in placenta previa (PP) and to establish a potential method of image interpretation.

Methods

US and MR examinations of 51 patients with PP were selected. The presence of imaging signs commonly used to detect PAS was assessed. Penalized logistic regression was performed considering histology as standard of reference; only signs statistically significant (p < 0.05) were considered for ROC and multivariate analysis. The probability of PAS according to the presence of US and/or MR signs was then assessed.

Results

At univariate analysis, loss of retroplacental clear space, myometrial thinning (MT) and placenta lacunar spaces on US, intraplacental dark bands (IDBs), focal interruption of myometrial border (FIMB) and abnormal vascularity (AV) on MR were statistically significant (p < 0.01). Three diagnostic methods for PAS were then developed for both US and MR when at least one (Method 1), two (Method 2) or three (Method 3) imaging signs occurred, respectively. Method 2 for MR showed a significantly (p < 0.05) higher accuracy (91%) compared to the other methods. When MR IDBs and AV as well as IDBs and FIMB were present in combination with US MT the probability of PAS increased from 75 to 90% and from 80 to 91%, respectively.

Conclusion

MR demonstrated a higher diagnostic accuracy than US to detect PAS. However, since the combination of MR and US signs could improve the probability to detect PAS, a complementary diagnostic role of these techniques could be considered.

  相似文献   
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