Objective:To compare the clinical efficacy between coracoclavicular ligament anatomical reconstruction and clavicular hook plate in the treatment of Neer Ⅱb distal clavicular fractures.Methods:A total of 64 patients with Neer Ⅱb clavicular fracture were treated at Department of Orthopaedics, The First Affiliated Hospital to Nanjing Medical University from September 2016 to June 2019. They were 35 males and 29 females, aged from 19 to 68 years (average, 50.7 years). They were assigned into 2 groups according to their operative methods: a reconstruction group of 30 cases undergoing coracoclavicular ligament anatomical reconstruction and a hook plate group of 34 cases undergoing fixation with a clavicular hook plate. The 2 groups were compared in terms of hospital stay, operation time, intraoperative blood loss, surgical incision length, postoperative coracoclavicular separation ratio, visual analogue scale (VAS) and Constant-Murley shoulder scores at 3, 6 and 12 months after operation, and postoperative complications.Results:There was no significant difference in general data between the 2 groups, showing comparability between groups ( P>0.05). Operations were completed uneventfully and surgical incisions healed by primary intention in both groups after operation. All the patients were followed up for 12 to 24 months (average, 14.6 months). The operation time [(74.6±22.0) min] and incision length [(10.4±0.4) cm] were significantly shorter but the intraoperative blood loss [(90.2±5.3) mL] was significantly less in the hook plate group than those in the reconstruction group [(95.6±20.8) min, (12.4±0.9) cm and (74.2±3.5) mL] ( P<0.05). There was no significant difference in hospital stay between the 2 groups ( P>0.05). At 3, 6 and 12 months after operation, the VAS scores (1.8±0.5, 1.2±0.3 and 1.1±0.2) and Constant-Murley scores (85.2±4.6, 91.1±2.6 and 92.1±2.2) in the reconstruction group were significantly better than those in the hook plate group (3.2±1.0, 1.6±0.3 and 1.5±0.3; 73.6±2.9, 85.9±4.6 and 87.0±3.1) ( P<0.05). At the last follow-up, the postoperative coracoclavicular separation ratio (elevation) in the hook plate group (0.20±0.16) was significantly greater than that in the reconstruction group (0.10±0.05) ( P<0.05). Conclusion:In the treatment of Neer ⅡB distal clavicular fractures, coracoclavicular ligament anatomical reconstruction may lead to better fixation and fewer postoperative complications than a clavicular hook plate, demonstrating fine clinical efficacy.

Objective:To compare the clinical efficacy of anatomical reconstruction of coracoclavicular ligament at the original insertion point and clavicular hook plate fixation in the treatment of acromioclavicular joint dislocation.Methods:Retrospective analysis was made on the data of 67 patients with acromioclavicular joint dislocation who received surgical treatment in the Department of Orthopaedics of the First Affiliated Hospital of Nanjing Medical University from June 2015 to January 2021. According to the surgical method, they were divided into reconstruction group (using the technique of anatomical reconstruction of coracoclavicular ligament at the original insertion point) and hook plate group (using the clavicular hook plate). There were 37 cases in the reconstruction group, including 26 males and 11 females, aged 47.2±9.6 years (range, 18-65 years), 13 cases on the left and 24 cases on the right. Among the 37 patients, 8 were sports injuries, 14 were falls, 11 were traffic accidents, and 4 were external force injuries. The average time from injury to surgery was 8.3±2.3 days. There were 30 cases in the hook plate group, including 24 males and 6 females, aged 47.4±9.7 years (range, 18-67 years), 12 cases on the left and 18 cases on the right. Among the 30 patients, 7 were sports injuries, 11 were falls, 9 were traffic accidents, and 3 were external force injuries. The average time from injury to surgery was 7.9±2.6 days. The surgical time, incision length, intraoperative bleeding, hospital stay, postoperative coracoclavicular separation ratio, and postoperative complications were compared between the two groups. Constant-Murley score and visual analog scale (VAS) were used to assess the shoulder joint function and pain degree of patients.Results:Both groups of patients were followed up, with a follow-up time of 12.3±0.4 months for the reconstruction group and 12.2±0.5 months for the hook plate group. The operation time (105.8±10.0 min), incision length [12.0 (11.0, 13.0) cm] and hospitalization time (6.8±2.1 d) in the reconstruction group were longer than those in the hook plate group [48.3±4.9 min, 10.0 (10.0, 11.0) cm, and 5.5±2.7 d], while the intraoperative blood loss (75.1±3.9 ml) was less than that in the hook plate group (90.3±6.3 ml), the differences were statistically significant ( P<0.05). The VAS [4.0 (3.0, 5.0), 3.0 (3.0, 3.0), 2.0 (1.0, 2.0) points] and Constant-Murley score (65.4±4.5, 84.9±2.5, 90.1±2.5 points) of the reconstruction group at 3 days, 3 months, and 12 months after surgery were better than those of the hook plate group [5.0 (4.0, 5.0), 4.0 (4.0, 4.0), 3.0 (3.0, 4.0) and 56.9±3.5, 79.6±4.0, 86.8±2.4 points], the difference was statistically significant ( P<0.05). At the last follow-up, there was a statistically significant difference in the separation ratio of coracoclavicular distance between the reconstruction group (0.12±0.08) and the hook plate group 0.22±0.15 ( t=3.25, P=0.002). There was no significant difference ( Z=-0.52, P=0.605) in the separation ratio of acromioclavicular distance [0.16 (0.05, 0.25) and 0.16 (0.04, 0.40)]. In the hook plate group, 6 cases had shoulder joint foreign body sensation and 2 cases had acromioclavicular joint redislocation (both Rockwood type III). Because the shoulder joint function did not affect their daily life, neither patient underwent secondary surgery. And no case of acromioclavicular joint redislocation occurred in the reconstruction group. Conclusion:Compared with the clavicular hook plate fixation, anatomic reconstruction of coracoclavicular ligament at the original insertion point in the treatment of acromioclavicular joint dislocation can reduce the pain of the shoulder joint earlier, which has the characteristics of small trauma, good effect, and reduces the steps of internal fixation removal, and has good clinical curative effect.

Isogenic cells growing in identical environments show cell-to-cell variations because of the stochasticity in gene expression. High levels of variation or noise can disrupt robust gene expression and result in tremendous consequences for cell behaviors. In this work, we showed evidence from single-cell RNA sequencing data analysis that microRNAs (miRNAs) can reduce gene expression noise at the mRNA level in mouse cells. We identified that the miRNA expression level, number of targets, target pool abundance, and miRNA-target interaction strength are the key features contributing to noise repression. miRNAs tend to work together in cooperative subnetworks to repress target noise synergistically in a cell type-specific manner. By building a physical model of post-transcriptional regulation and observing in synthetic gene circuits, we demonstrated that accelerated degradation with elevated transcriptional activation of the miRNA target provides resistance to extrinsic fluctuations. Together, through the integrated analysis of single-cell RNA and miRNA expression profiles, we demonstrated that miRNAs are important post-transcriptional regulators for reducing gene expression noise and conferring robustness to biological processes.