prospective study.
 
  IV, prospective cohort study without control group.
 IV, prospective cohort study without control group.
  Arthroscopic coracoid bone-block fixation by Endobutton was developed to avoid the complications associated with screwing. However, few studies have assessed the mechanical characteristics of the two. The aim of the present study was to assess and compare fixation rigidity by screw versus Endobutton. The study hypothesis was that rigidity is lower with Endobutton than with screws.
 
  3D print-outs of a glenoid and a coracoid process were obtained from CT scans of a patient showing anterior shoulder instability with significant bone defect. Four types of coracoid fixation were implemented 1 or 2 4.5mm malleolar screws, and 1 or 2 Endobuttons. Three specimens per assembly were placed on a specific test bench. Lateromedial bone-block compression was exerted at 0.1mm/sec at 3 points superior, central, inferior. The resultant force and bone-block displacement were recorded.
 
  Mean fixation rigidity with 1 screw, 2 screws, 1 Endobutton and 2 Endobuttons was respectively 158N/mm (range, 133-179), 249N/mm (241-259), 10N/mm (5-13) and 14N/mm (13-15), with significant difference between the screw and Endobutton groups (p<0.001). Displacement was greater with 1 than 2 Endobuttons under superior or inferior force, while the difference was non-significant under central force (7.45 vs 6.93mm; p=0.53) CONCLUSIONS Screw fixation showed greater rigidity, while the Endobutton assembly showed less tension, leading to greater bone-block mobilization. The interest of using two Endobuttons is to reduce displacement under polar pressure. the present biomechanical study confirmed the mechanical vulnerability of bone-blocks fixed by endobutton until consolidation is achieved.
 
  Biomechanical study.
 Biomechanical study.
  Many reports have described the relationship between medial meniscus posterior root tears (MMPRTs) and meniscal extrusion on coronal magnetic resonance (MR) images. However, volumetric assessment of meniscal extrusion has not been performed, and the correlation between extrusion length and volume remains unclear.
 
  Extrusion in both length and volume would be greater in MMPRTs than that in the normal medial meniscus, and the extrusion length measured on coronal MR images would be correlated with the extrusion volume.
 
  A total of 20 knees who underwent isolated MMPRTs without trauma history were included in the MMPRT group, and another 20 knees with normal medial meniscus were selected as the control group.  https://www.selleckchem.com/products/hc-7366.html  All 40 knees underwent 3-tesla MR imaging. The extrusion length of the medial meniscus was measured using coronal MR images only. Volumetric assessments of the meniscus were performed and analyzed via a semi-automatic segmentation. Group-wise comparisons of the extrusion length and volumetric values were conducted, and the correlation between the two measures in both groups was evaluated.
 
  The mean extrusion length of the medial meniscus in the MMPRT group was significantly longer (2.60 vs. 0.63mm; p<0.001) than that in the control group. The mean extrusion volume was also significantly higher in the MMPRT than that in the control group (770.93 vs. 193.80 mm
  ; p<0.001). The extrusion length was significantly and positively correlated with the extrusion volume in both groups (R=0.64; p=0.002 in MMPRT, R=0.73; p<0.001 in the control group).
 
  Semi-automatic segmentation was used to measure the volume of meniscal extrusion, which had previously only been estimated indirectly with the extrusion length on coronal MR images. MMPRTs significantly increased the extrusion in both measures. The extrusion length measured on coronal MR images was positively correlated with the extrusion volume in both groups.
 
  III, Case-control study.
 III, Case-control study.
  Does 3-months of gonadotrophin releasing hormone agonist (GnRHa) treatment before IVF improve clinical pregnancy rate in infertile patients with endometriosis?
 
  Single-blind, placebo-controlled clinical trial of 200 infertile women with endometriosis assigned to use GnRHa (study group) or placebo (control group) for 3 months before IVF. Clinical, embryological outcomes and stimulation parameters were analysed. Clinical pregnancy rate was the primary endpoint. In a subgroup of 40 patients, follicular fluid levels of oestradiol, testosterone and androstendione were measured. Gene expression profile of CYP19A1 was analysed in cumulus and mural granulosa cells.
 
  Implantation or clinical pregnancy rate were not significantly different between the two groups. Clinical pregnancy rates were 25.3% and 33.7% in the study and control groups, respectively (P = 0.212). Cumulative live birth rate was not significantly different 22.0% (95% CI 13.0 to 31.0) in the study group and 33.7% (95% CI 24.0 to 44.0) in the control group (P = 0.077). Ovarian stimulation was significantly longer and total dose of gonadotrophins significantly higher in the study group (both P < 0.001). Serum oestradiol levels on the day of HCG were significantly lower in the study group (P = 0.001). Cancellation rate was significantly higher in the study group (P = 0.042), whereas cleavage embryos were significantly more numerous in the control group (P = 0.023). No significant differences in the expression of CYP19A1 gene in mural or cumulus granulosa cells or steroid levels in follicular fluid between the two groups were observed, but testosterone was significantly lower in the study group (P < 0.001).
 
  Three-months of GnRHa treatment before IVF does not improve clinical pregnancy rate in women with endometriosis.
 Three-months of GnRHa treatment before IVF does not improve clinical pregnancy rate in women with endometriosis.The aim of this systematic review and meta-analysis was to assess the effect of oestrogen therapy as a preoperative intervention for improving clinical outcomes and fertility outcomes in women with intrauterine adhesions (IUA). A systematic search of PubMed, Embase, The Cochrane Library, clinicaltrials.gov, OVID and Chinese databases was carried out to identify relevant studies published before December 2019. Outcomes were expressed as odds ratios and 95% confidence intervals. Five cohort studies with moderate to high methodological quality were included in the meta-analysis. Preoperative oestrogen therapy was strongly associated with better clinical outcome at second-look hysteroscopy (OR 2.72; 95% CI 1.49 to 4.96; P = 0.001); whereas no significant difference was found in menstruation improvement and conception rate (OR 1.45; 95% CI, 0.95 to 2.23; P = 0.09; and OR 0.96; 95% CI 0.60 to 1.54; P = 0.87, respectively). The overall quality of the evidence ranged from moderate to very low. Preoperative oestrogen therapy may improve the short-term prognosis of IUA at second-look hysteroscopy, whereas the long-term prognosis-fertility outcome was similar to the control group.