Background: Recently, arthroscopic double-button Latarjet (AL) has provided an alternative to conventional open Latarjet (OL) in the treatment of anterior shoulder instability with glenoid bone loss. Therefore, theoretically, the faster fusion is obtained, the sooner return to sports under safe conditions can occur. The emerging flexible fixation of the bone block has clearly offered a new approach to achieve bone fusion. However, the period required to achieve this goal remains controversial. Purpose/Hypothesis: The purpose was to compare computed tomography (CT) scan results of AL and OL in the early postoperative period. It was hypothesized that the bone block fusion with AL would require a longer time than that with OL. Study Design: Cohort study; Level of evidence, 3. Methods: In a retrospective 1-year study, the authors compared 17 primary double-button AL to 22 primary 2-screw OL procedures indicated for anterior shoulder instability in patients with an Index Severity Instability Score >3 points. These patients were reviewed with a CT scan at 1 day, 3 months, and 6 months postoperatively. The characteristics for the 2 groups were comparable. CT scans aimed to analyze graft position, bone contact area with the scapula, and fusion at 3 and 6 months. Clinical assessment was based on the Walch-Duplay and Rowe scores. Results: The mean preoperative Index Severity Instability Score was 5.3 ± 1.9 points, with a mean anterior glenoid bone loss of 9.1% ± 4.6%. At 3 months, the rates of fusion were 41% and 100% for the AL and OL groups, respectively ( P < .001). This rate increased to 70% in the AL group at 6 months ( P = .006). In the axial and sagittal planes, there was no difference in graft position between the AL group and the OL group. The bone block was longer and there was a more extensive bone contact area in the OL group (AL, 131 mm2 vs OL, 223 mm2; P < .001). At 6 months of follow-up, no significant difference in clinical scores was noted between the groups: Walch-Duplay score, 93.0 ± 10.9 points versus 91.8 ± 12.5 points ( P = .867); and Rowe score, 99.0 ± 2.2 points versus 95.0 ± 8.4 points ( P = .307) for the AL and OL groups, respectively. Conclusion: AL required more time to achieve bone block fusion than OL. This finding should be taken into account when considering this procedure for patients in a hurry to return to sports involving the shoulder.

Telomerase catalytic subunit (hTERT) exerts important cellular functions including telomere homeostasis, genetic stability, cell survival and perhaps differentiation. However, the nature of external or internal signals, which regulate hTERT expression in tissues, remains poorly understood. Thus, whereas it has been described that hTERT gene is regulated along the differentiation of primitive myeloid progenitors, the effect of specific cytokines on telomerase expression in each myeloid lineage is currently unknown. Based on these considerations, we have investigated hTERT expression in erythroid cells treated with erythropoietin (EPO) and transforming growth factor b (TGFb), as putative positive and negative regulators, respectively. We describe here that EPO activates hTERT gene transcription in in vitro-expanded primary erythroid precursors as well as in UT7 erythroleukemia cells. In UT7 cells, this study shows also that EPO acts through a JAK2/STAT5/c-myc axis. In contrast, TGFb blocks EPO signaling downstream of c-myc induction through a Smad3-dependent mechanism. Finally, hTERT appears to be efficiently regulated by EPO and TGFb in an opposite way in erythropoietic cells, arguing for a role of telomerase in red blood cell production.

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Background: The arthroscopic bone block procedure according to Latarjet remains a controversial subject, and few comparative studies have demonstrated the benefit of arthroscopy over open surgery. Purpose/Hypothesis: The objective of this study was to compare both procedures by analyzing the short-term clinical results. The hypothesis was that the arthroscopic procedure is superior to the standard open procedure. Study Design: Cohort study; Level of evidence, 3. Method: This was a retrospective comparative study. Patients treated for chronic anterior instability by arthroscopic Latarjet with double cortical buttons (group A) or open Latarjet with screws (group O) with a minimum follow-up of 12 months were included. Intraoperative (duration, complications) and postoperative (complications, pain, mobility, functional scores, resumption of sport, Patient and Observer Scar Assessment Scale scar aesthetics, satisfaction) data were compared. Results: In total, 50 patients were included (n = 24 in group A, n = 26 in group O). Operating time was longer in group A (103 vs 61 min; P = .001). The average number of days on analgesics was higher in group A (8.9 vs 5.3 days; P = .04). The complication rate was similar for the 2 groups (12.5% vs 27%; P = .46). At 3 months, the loss of external rotation was greater in group A (–33° vs −18°; P = .01), and resumption of sports was less frequent (11% vs 48%; P = .01). At 12 months, the average scores were excellent, with no significants differences between the 2 groups: Walch-Duplay average, 90 points; Rowe, 94 points; Subjective Shoulder Value (SSV), 92.5%; sport SSV, 85%; and Patient and Observer Scar Assessment Scale score, 17.2 points. Conclusion: Over the short term, this comparative study did not prove the superiority of the cortical-button arthroscopic Latarjet procedure over the open Latarjet procedure. A delay in the resumption of sports, longer time to recover range of motion, and no benefit regarding postoperative pain or the aesthetic aspect of the scar were observed in this study with the arthroscopic procedure.

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