543 research outputs found
Cherubino and Antonio Domenici, ca. 1926
No full textCherubino (left) and Antonio (right) Domenici, proprietors of the Montezuma, a wholesale grocery at the corner of First Street and Lomas Boulevard. (Photo courtesy of Ida Matteucci.
Double-bundle anterior cruciate ligament reconstruction: a comparative cadaver study of the femoral tunnels performed with in-out and out-in techniques.
No full textIntroduction: Many authors have developed different techniques for reconstruction of both bundles (anteromedial AM; posterolateral PL) of the anterior cruciate ligament (ACL), in order to restore a normal kinematics. There are several factors that can influence biological integration of graft and the bundle’s mechanical behavior. The difference in diameter between tunnels on the intra-articular side and graft is one of most important. The aim of this study is to evaluate by CT-scan the femoral tunnel diameters performed using two different techniques. Methods: The study included 8 knees of 8 different cadavers divided into 2 groups. Group A: femoral tunnels were performed using an in-out technique: the PL tunnel from AM portal and the AM tunnel from transtibial PL tunnel. Group B: both tunnels were performed using an out-in technique with a guide developed by “senior author” (LP). A 7 mm reamer was used for all tunnels. The knees were then evaluated by CT-scan on coronal and axial planes. The diameters of the two tunnels were measured on both planes. Results: In group A, AM tunnel measured 7.07 mm (range 7 – 7.1) on axial plane and 7.02 mm (range 7 – 7.1) on coronal plane. In group B, AM tunnel measured 7.1 mm (range 7 – 7.2) on axial plane, and 7.15 mm (range 7 – 7.3) on coronal plane (p>0.05). In group A, PL tunnel measured 8.32 mm (range 8.2 – 8.4) on axial plane and 8.45 mm (range 8.4 – 8.5) on coronal plane. In group B, PL tunnel measured 7.15 mm (range 7 – 7.3) on axial plane and 7.02 mm (range 7 – 7.1) on coronal plane. (p<0.05). Discussion: There is not consensus on which is the best technique for double-bundle ACL reconstruction in terms of joint stability. Tunnel widening is one of the causes that may jeopardize the success of reconstruction and eventually a revision procedure. Several authors reported some difficulties in ACL revision surgery after single-bundle reconstruction when diameter of tunnel was larger than graft. Out-in technique shows a PL tunnel diameter similar to graft on intra-articular side. Theoretically, this approach can reduce the micro movements of the graft inside the tunnel due to the mismatch. Biomechanical and prospective randomized control studies between in-out and out-in techniques could confirm this hypothesis
Ricostruzione del legamento crociato anteriore con tecnica a doppio fascio: valutazione comparativa dei tunnel femorali eseguiti con tecnica in-out o out-in.
No full textIntroduzione. Recentemente sono state sviluppate diverse tecniche per la ricostruzione di entrambi i fasci (anteromediale, AM; posterolaterale, PL) del legamento crociato anteriore (LCA) con l’obiettivo di ripristinare una fisiologica cinematica articolare. Diverse sono le variabili che possono inficiare l’integrazione biologica degli innesti e ed il comportamento meccanico dei due fasci. La differenza tra il diametro dei tunnel all’emergenza articolare ed il diametro degli innesti è una tra queste.
Obiettivo dello studio è analizzare, mediante tomografia computerizzata (TC), i diametri dei tunnel femorali eseguiti con due diverse tecniche.
Materiali e Metodi. Lo studio ha incluso 8 ginocchia di 8 diversi cadaveri divisi in 2 gruppi.
Gruppo A: i tunnel femorali sono stati eseguiti mediante tecnica in-out. Il tunnel PL è stato eseguito attraverso il portale AM, mentre il tunnel AM attraverso il tunnel PL transtibiale.
Gruppo B: entrambi i tunnel, AM e PL, sono stati eseguiti mediante tecnica out-in utilizzando una guida sviluppata dal “senior author” (LP). Tutti i tunnel sono stati realizzati con una fresa da 7 mm. Entrambi i gruppi sono stati quindi sottoposti a valutazione TC con ricostruzioni sui piani coronale ed assiale. I diametri di entrambi i tunnel sono stati misurati sui due piani.
I dati sono stati analizzati con il Mann-Whitney t-test per campioni indipendenti. Il livello di significatività è stato posto a p<0.05.
Risultati. Il tunnel AM nel gruppo A era di 7.07 mm (range, 7 – 7.1) sul piano assiale e di 7.02 (range, 7 – 7.1) sul piano coronale. Il tunnel AM nel gruppo B era di 7.1 mm (range, 7 – 7.2) sul piano assiale e di 7.15 (range, 7 – 7.3) sul piano coronale. (p>0.05).
Il tunnel PL nel gruppo A era di 8.32 mm (range, 8.2 – 8.4) in assiale e di 8.45 (range, 8.4 – 8.5) in coronale. Il tunnel PL nel gruppo B era di 7.15 mm (range, 7 – 7.3) in assiale e di 7.02 (range, 7 – 7.1) in coronale. (p<0.05).
Discussione. Sino ad oggi non è stato dimostrato quale sia la migliore tecnica di ricostruzione a doppio fascio del LCA in termini di stabilità articolare e di evoluzione clinica. Tra le diverse variabili che possono condizionare il successo del trattamento ed un’eventuale revisione dell’innesto vi è l’allargamento dei tunnel femorali. Diversi autori hanno riportato, dopo ricostruzione a singolo fascio con diametri del tunnel femorale maggiore rispetto a quello dell’innesto, una maggiore difficoltà negli interventi di revisione del neolegamento.
L’esecuzione del tunnel femorale PL mediante tecnica out-in garantisce una migliore corrispondenza con il diametro dell’innesto all’emergenza articolare. Ciò riduce teoricamente la possibile instabilità del neofascio dovuta ad un diametro maggiore di partenza del tunnel osseo. Studi di biomeccanica in vitro e studi clinici prospettici randomizzati tra la tecnica in-out ed out-in potranno confermare tale ipotesi
Tecniche chirurgiche nel trattamento delle lesioni cartilaginee articolari: stato dell’arte
No full textThe marriage of Figaro, focused on the part of Cherubino
No full textThis thesis acquaint readers with the title of The marriage of Figaro and the role of Cherubino. The thesis describes the life and work of the author of The marriage of the Figaro, which is Pierre-Augustin Caron de Beaumarchais, composer Wolfgang Amadeus Mozart with a focus on his opera, and librettist Lorenzo da Ponte. Further, the work introduces the role of Cherubino and deals with the analysis of two Cherubino‘s arias. The aim of the analysis, both text and musical parts, was to bring the psychology of the figure as close as possible
“Scaffold” e cartilagine
No full textAutologous chondrocyte implantation (ACI) has demonstrated a high rate of clinical success despite a considerable number of complications. The second-generation ACI techniques require three-dimensional scaffolds. Midterm studies have demonstrated comparable results to ACI, yet with a decreased rate of complications. The aim of this review is to define the requisites of a scaffold and to report clinical results and limits of these techniques
Bone Morphogenetic Proteins
No full textThe bone morhogenetic proteins (BMPs) are a group of dimeric proteins in the trasforming growth factor- (TGF-) based on amino acid homology. More than 20 BMPs have been identified, several of which have significant osteogenic effects.
Since these proteins govern the three key steps in the bone induction cascade (chemotaxis and mitosis of mesenchymal cells, differentiation into cartilage and then replacement by bone) BMPs are true pleiotropic morphogens.
The biological action are mediated via specific BMP receptors found on the cell surface. These are serine/threonine kinases that phosphorylate intracellular proteins called Smads. The activated Smads are then traslocated to the nucleus, where they regulate either positive or negative expression of genes involved in bone formation.
There are different BMPs sources to use in orthopaedic practice.
The available amounts of BMPs, the morbidity associated with harvesting of the graft and the variability in success rate are issues to be considered in autografting.
The osteoinductive capacity of allograft (mineralized or demineralized) is highly variable and may be inadequate for any bone-inductive effect in humans.
A recombinant production system have several advantages: its reproducibility, high concentrations, consistent purity and activity of BMP, and ability to ensure freedom from adventitious agents. However, selection of the best carrier material is difficult in order to control retention time of BMP and localize its activity.
A partial solution is derived by ultraconcentration of autologous platelets that contains multiple growth factors delivered locally in physiological way. The amount of BMPs and a possible antagonism between different growth factors are still topics of discussion
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