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Anterior shoulder instability is a common pathology, particularly among active adolescents. In recent decades, our understanding of anterior shoulder instability and its management has evolved, with more emphasis on osseous abnormalities of the glenoid and humeral head, multidirectional instability, and patient factors that increase the risk of recurrence 1 . Although the arthroscopic Bankart repair is often considered the first-line treatment for anterior shoulder instability, concerns regarding high failure rates exist, specifically in younger patients and/or those with >15% glenoid bone loss 1 . The Latarjet procedure, which functions to improve stability by increasing the glenoid width and by using the sling effect, is often considered an effective treatment option in these cases 2 . As a result of the complexity of many of the factors that contribute to anterior shoulder instability, optimal surgical management remains controversial.We commend Waltenspül et al. for their long-term retrospective analysis of adolescents who underwent an arthroscopic Bankart repair or an open Latarjet procedure for the treatment of recurrent anterior shoulder instability. In their study, with failure defined as redislocation or persistent anterior apprehension, the authors reported failure rates of 57% for arthroscopic Bankart repair and 6% for open Latarjet procedures. This led the authors to conclude that surgeons should consider the open Latarjet procedure for primary treatment of recurrent anterior shoulder instability in adolescents. These results are in contradiction to most other studies on arthroscopic Bankart repair. Although the high failure rate is concerning, it is important to recognize the methodological limitations of the study, as it was not appropriately designed to compare the 2 treatments. Preoperatively there were significant differences in group characteristics, and there was limited discussion of indications for Bankart repair, raising major concerns for selection bias. Additionally, there are concerns about the technical aspects of the arthroscopic repairs and the experience of the surgeons performing them. Included Bankart repairs utilized a mean of 3 anchors, but as few as only 1 anchor. The number of anchors, in conjunction with the utilization of anchors of an outdated design, may indicate inadequate fixation and the use of improper surgical technique 3 . Finally, the study included 81 total cases compiled from 12 surgeons over a 10-year period, raising substantial concerns with regard to surgeon volume and its relationship to the reported outcomes.Although we undoubtedly agree that, in specific circumstances, the Latarjet procedure is a superior option to the arthroscopic Bankart repair, it must be recognized that proceeding with a nonanatomic procedure is a nuanced decision that is not without risk 2 . This choice is complicated further in the adolescent population given their potential need for a future surgical procedure on a nonnative shoulder, the inherently smaller size of the coracoid in a gro...

U6 RNA contains a 1 × 2-nt internal loop that folds and unfold during spliceosomal assembly and activation. The 1 × 2 loop consists of a C 67 •A 79 base pair that forms an additional hydrogen bond upon protonation, C 67 •A + 79 , and uracil (U80) that coordinates the catalytically essential magnesium ions. We designed a series of RNA and DNA constructs with a 1 × 2 loop sequence contained in the ISL, and its modifications, to measure the thermodynamic effects of protonation and magnesium binding using UV-visible thermal denaturation experiments. We show that the wild-type RNA construct gains 0.43 kcal/mol in 1 M KCl upon lowering the pH from 7.5 to 5.5; the presence of magnesium ions increases its stability by 2.17 kcal/mol at pH 7.5 over 1 M KCl. Modifications of the helix closing base pairs from C-G to U•G causes a loss in protonation-dependent stability and a decrease in stability in the presence of magnesium ions, especially in the C68U construct. A79G single-nucleotide bulge loop construct showed the largest gain in stability in the presence of magnesium ions. The DNA wild-type construct shows a smaller effect on stability upon lowering the pH and in the presence of magnesium ions, highlighting differences in RNA and DNA structures. A U6 RNA 1 × 2 loop sequence is rare in the databases examined.

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Traumatic posterior dislocations of the shoulder can result in bony defects, labral tears, and cartilage injuries of the glenohumeral joint. Although traditional Hill-Sachs lesions from anterior dislocations are more commonly identified, reverse Hill-Sachs lesions caused by posterior dislocation often leads to recurrent engagement of the humeral head with the glenoid and significantly greater damage to the humeral chondral surface. In severe traumatic cases, concomitant damage of the capsulolabral soft tissues, such as circumferential labral lesions, can lead to chronic shoulder instability and residual glenoid bone loss. These lesions further add to the complexity of managing patients with posterior dislocations of the shoulder because of the challenges of achieving adequate anatomic reduction and tensioning of the capsulolabral junction, while also using a combination of arthroscopic and open-labral repair techniques. In the setting of reverse Hill-Sachs lesions treatment, it is important to address the bony and cartilage defect. The purpose of this Technical Note is to describe our preferred technique for arthroscopic repair of circumferential lesions of the glenoid labrum causing multidirectional instability with concomitant reverse Hill-Sachs Lesion treatment with fresh talus osteochondral allograft.