Arthroscopic Bankart Repair Using a Lasso-Loop Stitch

Anterior inferior shoulder dislocation is a common injury. After primary traumatic shoulder dislocation and conservative treatment, the risk of re-dislocation is very high in patients younger than 35 years. With age, the risk of re-dislocation after traumatic shoulder dislocation and conservative treatment decreases. Surgical treatment via either open or arthroscopic stabilization minimizes the risk of re-dislocation. Today, anterior shoulder stabilization by arthroscopic refixation of the labroligamentous complex with suture anchors is a standard procedure, if there is no severe chronic bony defect at the glenoid site. Lafosse et al. described the so-called „Lasso-loop stitch“. This technique allows for positioning of the knot away from the joint and at the same time it establishes a labral bump that stabilizes the humeral head against (sub)luxation. The surgical principle and aim consist of refixation of the anterior labrum-capsule-ligament complex to the glenoid with positioning of the knot at distance to the joint as well as bulging up the labrum. This stabilizes the shoulder joint and therefore avoids further dislocations and associated pathologies. The aim of this work is to give an illustrated instruction of the surgical technique of arthroscopic Bankart repair using the lasso-loop stitch

Monocytes Do Not Transdifferentiate into Proper Osteoblasts

Recent publications suggested that monocytes might be an attractive cell type to transdifferentiate into various cellular phenotypes. Aim was, therefore, to evaluate the potential of blood monocytes to transdifferentiate into osteoblasts. Monocytes isolated from peripheral blood were subjected to two previously published treatments to obtain unique, multipotent cell fractions, named programmable cells of monocytic origin (PCMOs) and monocyte-derived mesenchymal progenitor cells (MOMPs). Subsequently, MOMPs and PCMOs were treated with osteogenic differentiation medium (including either vitamin D or dexamethasone) for 14 days. Regarding a variety of surface markers, no differences between MOMPs, PCMOs, and primary monocytes could be detected. The treatment with osteogenic medium neither resulted in loss of hematopoietic markers nor in adoption of mesenchymal phenotype in all cell types. No significant effect was observed regarding the expression of osteogenic transcription factors, bone-related genes, or production of mineralized matrix. Osteogenic medium resulted in activation of monocytes and appearance of osteoclasts. In conclusion, none of the investigated monocyte cell types showed any transdifferentiation characteristics under the tested circumstances. Based on our data, we rather see an activation and maturation of monocytes towards macrophages and osteoclasts

Transpedicular drilling

Für die konstruktive Auslegung eines navigationsgestützten, semiaktiven Leichtbauroboters (DLR) wurde die auftretende mechanische Belastung der transpedikulären Bohrung untersucht. Zur Ermittlung der Schneidkräfte und –momente fanden Bohrungen bzw. Fräsungen am Kunststoffknochen, an der Rinderwirbelsäule und der Schweinescapula statt. Getestet wurden medizinische und industrielle Bohr- und Fräswerkzeuge mit medizinischen Antriebsmaschinen. Die Auswertung der Daten erfolgte rechnerunterstützt mit der analytischen Software Matlab. Da der Eintrittswinkel in den dorsalen Bereich des Wirbels einen großen Einfluss sowohl auf die Schneidekräfte und –momente als auch auf die Bohrlochqualität hat, wurde der optimale Bohrkanal an Lendenwirbeln untersucht. Die Untersuchungen erfolgten mit Hilfe der visualisierungssoftware „Amira“ sowie der Software Matlab. Aus CT-Datensätzen konnten 3D Modelle der ersten Ledenwirbelkörper erzeugt werden. Zusätzlich konnte mit diesem Verfahren die durchschnittliche Länge der Pedikelschrauben, der Winkel zwischen Pedikelschraubenachse und Sagittalebene und die dorsale Kortikalisdicke rechnergestützt ermittelt werden.The mechanical forces arising from transpedicular drilling were analysed as a basis for the construction of a semi-active light constructed robot guided by a navigation system. For evaluation of the cutting forces, the drilling and milling of artificial bone and of animal spine and scapula were performed. Medical and industrial drilling- and milling cutters were tested with medical machines. The data was analysed using the software “Matlab”. Tests were carried out to establish the optimal angle of entry into the dorsal area of the vertebra, because this has a huge impact on both the cutting forces and the quality of the drill hole,. The Date was then analysed, again the software “Matlab” as well as the software “Amira” for visualisation. The optimal position of the pedicle screw could be calculated by creating 3D models of the first lumbar vertebrae by using CT-data. Furthermore, using this method the entrance angle of the drill at the dorsal vertebra, the mean length of the pedicle screws, the angle between the axis of the pedicle screw and the sagital plane and the thickness of the dorsal cortical bone in the area of the pedicle screw entry could be evaluated