[Research progress on long non-coding RNA (lncRNA) in osteoarthritis].

Osteoarthritis(OA) is a common clinical disease. The incidence of OA increases significantly with age, and the quality of life of patients is seriously affected. In the pathogenesis of OA, cartilage degeneration is the main cause. There are many long non-coding RNA (lncRNA) specifically expressed in osteoarthritis, which is closely related to the occurrence and development of osteoarthritis. Based on the latest research from 2014 to 2019, this paper summarizes the differential expression of lncRNA in osteoarthritis, the mechanism of lncRNA regulating chondrocyte function, and the mechanism of lncRNA regulating cartilage matrix metabolism. The fact that the expression of lncRNA is altered at different stages of OA development indicates that lncRNA can be developed forlife. The biomarkers and therapeutic targets can provide reference for the prevention, treatment and research of osteoarthritis.

[Effectiveness of percutaneous compression plate fixation for femoral neck fractures].

OBJECTIVE: To investigate the effectiveness of percutaneous compression plate (PCCP) fixation for femoral neck fracture. METHODS: A clinical data of 100 patients with femoral neck fractures who were treated with internal fixation were analyzed retrospectively. The fractures were fixed with the cannulated screws (CS) in 55 patients (CS group) and with the PCCP in 45 patients (PCCP group). There was no significant difference in gender, age, the cause of injury, the fracture type, complications, and disease duration between the two groups ( P>0.05). The quality of fracture reduction, bone resorption, screw slipping, femoral neck shortening, complications (nonunion, failure of fixation, and osteonecrosis of femoral head), and functional recovery of hip (Harris score) were compared between the two groups. RESULTS: All incisions healed by first intention. All patients were followed up 24-56 months, with an average of 30.7 months. The quality of fracture reduction was excellent in 26 cases, good in 18 cases, fair in 9 cases, and poor in 2 cases in CS group and excellent in 21 cases, good in 17 cases, fair in 4 cases, and poor in 3 cases in PCCP group, showing no significant difference between the two groups ( Z=-0.283， P=0.773). The incidence of nonunion in PCCP group was significantly lower than that in CS group ( P=0.046), and the fracture healing time in PCCP group was shorter than that in CS group ( t=2.155, P=0.034). There was no significant difference in the incidences of bone resorption, screw slipping, femoral neck shortening, failure of fixation, and osteonecrosis of femoral head between the two groups ( P>0.05). The overall complication rates were 27.27% (15/55) in CS group and 8.89% (4/45) in PCCP group, showing significant difference ( χ 2=5.435, P=0.020). The Harris score in PCCP group at 6 months after operation was significantly higher than that in CS group ( t=-2.073, P=0.041). However, there was no significant difference in the Harris score at 12, 18, and 24 months after operation between the two groups ( P>0.05). CONCLUSION: Stable sliding compression of PCCP is benefit for the femoral neck fracture healing, especially shortening union.

[Treatment of dislocation of acromioclavicular joint with TightRope fixation through a small incision in the base of coracoid process].

OBJECTIVE: To explore the method and effect of small incision TightRope fixation in the treatment of fresh acromioclavicular joint dislocation. METHODS: From January 2016 to May 2018, 28 cases of fresh acromioclavicular dislocation were treated, including 20 males and 8 females, aged 26 to 87 years with an average age of 51.3 years. The modified Rockwood classification included 1 case of typeⅡ, 22 cases of typeⅢand 4 cases of type V. The average time from injury to operation was 2.4 days. The operative time, shoulder function recovery time and postoperative complications were recorded, and the immediate reduction effect and Karlsson function of shoulder joint were evaluated. RESULTS: In 28 patients, only one Rockwood typeⅡ was used to reconstruct the pyramidal ligament, and the other 27 were used to reconstruct the pyramidal ligament and the trapezoid ligament. The average operation time was (66.50±12.62) min (including intraoperative fluoroscopy time). Twenty-eight cases were followed up for 11 to 20 (16.7±4.6) months. The recovery time of shoulder function was 2 to 7 months with an average of 4 months. During the follow-up period, 1 case had osteolysis and loss of reduction at the clavicular plate site, and the rest had no complications such as re-dislocation and button plate prolapse. Immediate reduction effect after operation:6 cases with reduction insufficiency, 17 cases with complete reduction and 5 cases with excessive reduction;Karlsson function evaluation of shoulder joint in the last follow-up:excellent in 21 cases, good in 6 cases and poor in 1 case;Pearson analysis r=0.060, suggesting that the immediate reduction effect of fresh acromioclavicular dislocation operation has no significant correlation with Karlsson function evaluationof shoulder joint in the last follow-up. CONCLUSION: TightRope fixation through a small incision in the base of coracoid process is a simple and effective method for the treatment of dislocation of acromioclavicular joint. There was no significant correlation between the slight difference of immediate reduction effect within 5 mm and Karlsson function evaluation of shoulder joint in the last follow-up. It is suggested to pay attention to the loss of reduction and osteolysis of clavicular plate in clinical follow-up.

A Cone-Beam Computed Tomographic Study on Mandibular First Molars in a Chinese Subpopulation.

The purpose of this study was to conduct a cone-beam computed tomographic (CBCT) investigation on the root and canal configuration of the mandibular first molars, especially the morphology of the disto-lingual (DL) root, in a Chinese subpopulation. A total of 910 CBCT images of the mandibular first molars were collected from 455 patients who underwent CBCT examinations as a preoperative assessment for implants or orthodontic treatment. The following information was analyzed and evaluated: tooth position, gender, root and root canal number per tooth, root canal type of the mesial root(s) and distal root(s), angle of the DL root canal curvature, distance between two distal canal orifices in the teeth with DL root, and angle of disto-buccal canal orifice-disto-lingual canal orifice-mesio-lingual canal orifice (DB-DL-ML). Most of the mandibular first molars (64.9%, n = 591) had two roots with three root canals, and most of the mesial root canals (87.7%, n = 798) were type VI. The prevalence of the DL root was 22.1% (n = 201). The right side had a higher prevalence of DL root than the left side (p<0.05). Additionally, the curvature of the DL root canal were greater in the bucco-lingual (BL) orientation (30.10°±14.02°) than in the mesio-distal (MD) orientation (14.03°± 8.56°) (p<0.05). Overall there was a high prevalence of DL root in the mandibular first molars, and most of the DL roots were curved in different degrees. This study provided detailed information about the root canal morphology of the mandibular first molars in a Chinese subpopulation.

[Case-control study on therapeutic effects of different fixation methods with three Kirschners wires for the treatment of humeral supracondylar fractures].

OBJECTIVE: To compare therapeutic effects of three fixation methods with three Kirschner wires,and to find the best fixation method. METHODS: From July 2008 to May 2009, 60 patients with humeral supracondylar fractures were treated. Among patients in Group A, 11 patients were male and 9 patients were female, ranging from 2 to 13 years old,with an average of (5.4 +/- 0.5)years;all the patients in Group A were fresh closed fractures without nerve and blood vessel injuries, 13 patients were type II and 7 patients were type III according to Gartland classification; and all the patients in Group A were treated by three Kirschner wires fixation with the third Kirschner different wire fixed through radial edge of coronoid fossa. Among patients in Group B, 13 patients were male and 7 patients were female,ranging from 2 to 11 years old, with an average of (6.1 +/- 0.4) years; all the patients in Group B were fresh closed fractures without blood vessel injuries, 11 patients were type II and 9 patients were type III according to Gartland classification, 2 patients had ulnar nerve injuries before treatment; and all the patients in Group B were treated by three Kirschner wires fixation with the third Kirschner different wire fixed through ulnar edge of coronoid fossa. Among patients in Group C, 8 patients were male and 12 patients were female, ranging from 3 to 14 years old, with an average of (7.4 +/- 0.6) years; all the patients in Group C were closed fresh fractures without blood vessel injuries, 7 patients were type II and 13 patients were type III according to Gartland classification, 2 patients had radial nerve injuries before treatment; and all the patients in Group C were treated by three Kirschner wires fixation with the third Kirschner different wire fixed through middle of coronoid fossa. After 1 year of treatment,the Carrying and Baumann angles were measured on the X-ray of all patients in the three groups, and the motion range of elbow joint was observed. The Flynn evaluation criteria were used to compare therapeutic effects among the three groups. RESULTS: All the patients were followed up. The function loss of elbow joint were (14.04 +/- 3.25) degrees in Group A, (13.14 +/- 2.34) degrees in Group B, and (9.25 +/- 2.56) degrees in Group C. Changes of Carrying angle were (7.64 +/- 1.78) degrees in Group A; (7.38 +/- 1.68) degrees in Group B, and (5.27 +/- 1.13) degrees in Group C. Changes of Baumann angle were (28.55 +/- 3.23) degrees in Group A, (27.55 +/- 2.23) degrees in Group B, (21.45 +/- 1.73) degrees in Group C. According to Flynn criteria, there were 11 patients got excellent result, 4 good and 5 poor in Group A; in Group B, 12 patients got excellent result, 3 good and 5 poor; in Group C, 11 patients got excellent result, 6 good and 3 poor. The therapeutic effects of Group C was better than those of Group A and Group B. CONCLUSION: There are different effects among three kinds of operative approaches for the humerus supracondylar fractures. The fixation method with one Kirschner wire through middle part of coronoid fossa is better than the other two fixation methods.