BACKGROUND:There is no literature about the treatment according to the mechanism of cervical spine injury classification, especial y for the treatment of extension type cervical fracture/dislocation with merger cases of posterior composite structure damage, whether simple anterior approach can meet the needs of the treatment has no detailed elaboration. This article may analyze from the aspect of cervical spine injury mechanism. OBJECTIVE:To observe the short-term effect of anterior cervical Cage-assisted fusion combined with locking titanium plate internal fixation for the treatment of extension type cervical fracture. METHODS:A retrospective analysis was performed in 15 extension type cervical spine fracture dislocation patients treated with decompression anterior cervical intervertebral disc resection plus bone graft with cage-fusion locking titanium plate internal fixation from June 2006 to March 2011 in the Department of Orthopedics, Xianning Central Hospital, including 10 cases of single segment injury and treatment, and five cases of multiple segment injury and treatment. Japanese Orthopaedic Association score and the neck disability index were compared before and after treatment;the cervical flexion and height were measured according to the antersposterior X-ray film taken before fixation, 1 week after fixation and final fol ow-up.RESULTS AND CONCLUSION:The patients were fol owed-up for 8-37 months. One case had Cage mild sinking and shift, and there was no internal fixation breakage or loosening in al the patients. Transient pharyngeal discomfort was observed in 11 patients. Compared with the preoperation, the Japanese Orthopaedic Association score, neck dysfunction index, fusion segment cervical flexion and fusion segment intervertebral disc height were significantly improved at 1 week after fixation and final fol ow-up (P<0.05). There were no significant differences between 1 week after fixation and final fol ow-up (P>0.05). The short-term effect of decompression anterior cervical intervertebral disc resection plus bone graft with cage-fusion locking titanium plate internal fixation for the treatment of extension-type cervical fracture is good.

Objective:To explore the mechanism of the alternation of RR interval length in atrioventricular reentrant tachycardia (AVRT).Methods:From August 2009 to August 2016, 317 patients with AVRT were treated by radiofrequency catheter ablation in cardiology department of TEDA International Cardiovascular Hospital were analyzed retrospectively.During AVRT, 5 mg of verapamil was given slowly intravenously for 10 min.After administration, the changes of RR interval, AH interval, HV interval and VA interval were observed and the time of changes was also observed.Results:After administration of verapamil, there were 8 patients with RR interval alternation and QRS wave alternation.When RR interval alternation occurred, the difference of AH interval between adjacent heart beats was gradually extended, without AH jump, and the HV interval and VA interval were constant.This phenomenon occurred 6-17 minutes after administration, and the average cycle of tachycardia was 16-42 ms longer than before administration.In 3 patients, RR interval alternation occurred.When the phenomenon disappeared, the difference of AH interval between adjacent heart beats was gradually shortened, there was no AH jump, and the interval between HV and VA was constant until AH interval was equal, the disappearance time was 19-57 min after administration; AVRT was terminated in 5 patients after administration.Conclusion:It can be concluded that the mechanism is due to the frequency dependent decreasing conduction of AH interval in tachycardia, which can not be induced by program stimulation.

Objective:To compare the advantages and disadvantages of hemiarthroplasty (HA) and reverse shoulder arthroplasty (RSA) in the treatment of complex proximal humeral fractures in the elderly patients.Methods:Pubmed, the Cochrane Library, EMBASE, and Chinese databases like CNKI, Wanfang Data and Weipu were searched for studies comparing HA and RSA in the treatment of complex proximal humeral fractures in the elderly (>60 years) from 2000 to 2020. After the studies were included and excluded by a set of inclusion and exclusion criteria and evaluated for their quality, their radiological and functional data were extracted and analyzed using software Stata 14.0.Results:Included in this meta-analysis were 11 studies with a total of 771 patients. RSA was superior to HA in outcomes like forward flexion ( SMD=-1.043, 95% CI: -1.551 to -0.534, P=0.000), abduction ( SMD=-0.811, 95% CI: -1.470 to -0.153, P=0.016), Constant score ( SMD=-0.699, 95% CI: -1.118 to -0.280, P=0.001), American Shoulder Elbow Surgeons’ Form (ASES) ( SMD=-0.931, 95% CI: -1.256 to -0.606, P<0.001), and Simple Shoulder Test (SST) ( SMD=-0.598, 95% CI: -1.181 to -0.016, P=0.044). HA led to a higher complication rate ( RR=2.14, 95% CI: 1.11 to 4.14, P=0.024), a higher joint stiffness rate ( RR=6.467,95% CI: 1.923 to 21.755, P=0.003) and a higher revision rate ( RR=5.796, 95% CI: 1.927 to 17.434, P=0.002). There were no statistically significant differences between RSA and HA in tuber healing rate ( RR=0.850, 95% CI: 0.669 to 1.080, P=0.182), internal rotation ( SMD=0.536, 95% CI: -0.394 to 1.466, P=0.259), external rotation ( SMD=-0.366, 95% CI: -0.916 to 0.184, P=0.192), implant infection ( RR=1.550, 95% CI: 0.330 to 7.286, P=0.579) or Disabilities of the Arm, Shoulder and Hand (DASH) score ( SMD=0.286, 95% CI: -0.278 to 0.850, P=0.032). Although there was no significant difference between RSA and HA in visual analogue scale (VAS) score ( SMD=0.440, 95% CI: -0.113 to 0.993, P=0.119), RSA scored better ( SMD=-1.101, 95% CI: -2.090 to -0.112, P=0.029). Conclusion:For elderly patients (>60 years) with complex proximal humeral fracture, RSA may be a more effective surgical intervention which can lead to better early and mid-term clinical outcomes than HA.

Objective:To design an anatomical plate of ulna coronoid process using 3D printing and computer model design software based on a collection of CT scanning data of the ulna coronoid process.Methods:The CT scans of the elbow joint with no obvious anatomic variation, no fracture, or no history of elbow operation were collected which had been taken at Trauma Center, The First Affiliated Hospital of Kunming Medical University from September 2017 to January 2022. There were 52 males and 50 females. RadiAnt DICOM Viewer and Mimics Medical 21.0 were used to visualize the CT data of the elbow joint of 102 volunteers. The software was used to measure the angle between the tip of the ulna coronoid process and the tuberosity of the ulna, the width at 1/2 height of the ulna coronoid process, the distance between the tip of the ulna coronoid process and the horizontal plane of the ulna tuberosity, and the safety angle for screw placement. After the values were measured, Siemens Ungraphics NX12.0 software was used to design the anatomical plate and the screw guide device of the ulna coronoid process. After the plate model was designed, a 1:1 actual plate model of the ulna coronoid process was produced by 3D printing. The actual plate model was placed onto an adult model of the ulna coronoid process and an adult cadaveric specimen of the ulna coronoid process to verify its matching degree. An in vitro operation was simulated using the plate model to verify its operability. Results:There were no significant differences between the left and right sides in the angle between the tip of the ulna coronoid process and the tuberosity of the ulna, the width at 1/2 height of the ulna coronoid process, the distance between the tip of the ulna coronoid process and the horizontal plane of the ulna tuberosity, or the safety angle for screw placement in either males or females ( P>0.05). There were no significant differences between males and females in the angle between the tip of the ulna coronoid process and the tuberosity of the ulna or in the safety angle for screw placement ( P>0.05). There were statistically significant differences between males and females in the width of 1/2 height of the ulna coronoid process and the distance between the tip of the ulna coronoid process and the horizontal plane of the ulna tuberosity ( P<0.05). However, the experiments on computer simulative adaptation and plate model simulative adaptation found that the anatomical plates of the ulna coronoid process designed on various parameters of males and females were exchangeable, leading to similarly good marching degrees and safe angles for screw placement. Conclusions:The anatomical plate of the ulna coronoid process designed in this study demonstrates a good fit and a safe angle for screw placement, basically achieving the goal expected to provide a basis for fabrication of a titanium alloy plate. In design of an anatomical plate of ulna coronoid process, it is not necessary to differentiate males from females or to differentiate the left side from the right one, because only a general plate can be used for both males and females and for both the left and the right sides.

Objective: To compare the influence of extraction and retention of the intruded dogs' teeth on permanent successors. Methods: Nine healthy 45-days-old Chinese rural puppies were selected, and six were submitted to the intrusion of the bilateral canine. Intruded teeth on the left side were extracted 30 minutes later and the teeth on the right side were kept in their sockets. After 8 months, all dogs were sacrificed. General observation, periapical radiograph and cone beam CT were used to observe the preoperative and postoperative deciduous teeth, permanent germs and permanent teeth development. The structure and content of successors' enamel were observed by scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). Results: In the extraction groups, the enamel hypoplasia was found in 19 permanent successors, ectopic eruption in 2 cases and abnormal teeth were in 19 cases in total (79%). In the retention groups, enamel hypoplasia of the permanent successors occurred in 2 cases, root dilaceration in 6 cases, and ectopic eruption in 5 cases, retained deciduous teeth in 3 cases, and there were 22 abnormal teeth in total (92%). In blank control group, there was no abnormal teeth. The major effect of intruded deciduous teeth on the permanent successors exhibited enamel hypoplasia [85% (41/48)], presented as enamel coloration and enamel defect (P=0.416). Conclusions The intruded deciduous teeth should be removed early in order to reduce the effect on the permanent teeth.

Lower extremity deep vein thrombosis (DVT) is one of the main complications in patients with traumatic fractures, and for severe patients, the DVT can even affect arterial blood supply, resulting in insufficient limb blood supply. If the thrombus breaks off, pulmonary embolism may occur, with a high mortality. The treatment and rehabilitation strategies of thrombosis in patients with lower extremity fractures have its particularity. DVT in traumatic fractures patients has attracted extensive attention and been largely studied, and the measures for prevention and treatment of DVT are constantly developing. In recent years, a series of thrombosis prevention and treatment guidelines have been updated at home and abroad, but there are still many doubts about the prevention and treatment of DVT in patients with different traumatic fractures. Accordingly, on the basis of summarizing the latest evidence-based medical evidence at home and abroad and the clinical experience of the majority of experts, the authors summarize the clinical treatment and prevention protocols for DVT in patients with traumatic fractures, and make this consensus on the examination and assessment, treatment, prevention and preventive measures for DVT in patients with different fractures so as to provide a practicable approach suitable for China ′s national conditions and improve the prognosis and the life quality of patients.

TSCI have dyskinesia and sensory disturbance that can cause various life-threaten complications. The patients with traumatic spinal cord injury (TSCI), seriously affecting the quality of life of patients. Based on the epidemiology of TSCI and domestic and foreign literatures as well as expert investigations, this expert consensus reviews the definition, injury classification, rehabilitation assessment, rehabilitation strategies and rehabilitation measures of TSCI so as to provide early standardized rehabilitation treatment methods for TSCI.

Since December 2019, novel coronavirus pneumonia (NCP) has been reported in Wuhan, Hubei Province, and spreads rapidly to all through Hubei Province and even to the whole country. The virus is 2019 novel coronavirus (2019-nCoV), never been seen previously in human, but all the population is generally susceptible. The virus spreads through many ways and is highly infectious, which brings great difficulties to the prevention and control of NCP. Based on the needs of orthopedic trauma patients for emergency surgery and review of the latest NCP diagnosis and treatment strategy and the latest principles and principles of evidence-based medicine in traumatic orthopedics, the authors put forward this expert consensus to systematically standardize the clinical pathway and protective measures of emergency surgery for orthopedic trauma patients during prevention and control of NCP and provide reference for the emergency surgical treatment of orthopedic trauma patients in hospitals at all levels.