Objective To evaluate the effect of pacing in different parts of the ventricle on left ven-tricular mechanical asynchrony using myocardial metabolic imaging.Methods A total of 56 elderly patients undergoing permanent pacemaker implantation in our hospital from January to November 2023 were recruited and randomly divided into left bundle branch pacing(LBBAP)group and right ventricular pacing(RVP)group,with 28 patients in each group.Another 28 elderly patients who did not undergo pacemaker implantation surgery were selected as the control group.Within 1 week after pacemaker implantation,18F fluorodeoxyglucose(18F-FDG)positron emission tomo-graphy(PET)/CT myocardial metabolism imaging was performed to analyze PET myocardial metabolism images and evaluate left ventricular mechanical synchrony.Results The LVEF was significantly higher in the control group than the LBBAP group and RVP group[(67.68±9.61)％vs(62.71±11.33)％vs(57.36±16.07)％,P=0.012],but no such difference was seen between the LBBAP group and the RVAP group(P＞0.05).The LBBAP group had obviously lower pat-tern standard deviation(PSD),phase histogram bandwidth(PHBW),entropy,summed motion score(SMS),summed thickening score(STS),extent of abnormal motion(Mot Ext)and thicken-ing extent(Thk Ext)when compared with the RVP group(P＜0.01).There were no statistical significant differences in the terms of PSD,PHBW,Entropy,SMS,STS,Mot Ext,and Thk Ext between the LBBAP group and the control group(P＞0.05).Conclusion 18F-FDG PET/CT myo-cardial metabolic imaging can be used to evaluate left ventricular mechanical synchrony in pacing different parts of the ventricle,and LBBAP can obtain better left ventricular synchrony parame-ters than RVP,similar to the control group.

Objective:To investigate the clinical and imaging characteristics of cervical spine hyperextension injury plus multilevel disco-ligamentous complex (MDLC) injury and the therapeutic effectiveness of their treatment.Methods:A total of 456 patients with cervical hyperextension injury were hospitalized between January 2010 and October 2020 at Department of Orthopaedics, The 909th Hospital, Dongnan Hospital Affiliated to Xiamen University. A retrospective study was conducted to analyze the clinical data of the 43 patients among them who had been diagnosed with MDLC injury and undergone surgical treatment and been fully followed up. They were 37 males and 6 females with an age of (50.6±10.7) years. According to the American Spinal Injury Association (ASIA) grading, there were 1 case of grade A, 8 cases of grade B, 18 cases of grade C, and 16 cases of grade D. The Japanese Orthopaedic Association (JOA) score was (7.9±1.6) points. Anterior cervical decompression, fusion and internal fixation were conducted for 42 patients, and posterior total laminectomy and internal fixation for 1 patient. The clinical and imaging manifestations of the patients, and the consistency between preoperative and intraoperative diagnosis of disco-ligamentous complex (DLC) injury were analyzed. ASIA grading and JOA score were used to assess the outcomes of surgical treatment and comparisons were made between preoperation and postoperation.Results:DLC injury existed at 99 levels (43 cases), with a high incidence at level C 5-6 (30 cases), and high-signal manifestations of cervical cord injury existed at 48 levels, with a high incidence at level C 3-4 (16 cases). Two-segment DLC injury was the most common [74.4% (32/43)], while three-segment DLC injury existed in 9 cases and four-segment DLC injury in 2 cases. There were 21 cases of jumping MDLC injury and 22 cases of continuous MDLC injury. At preoperation, DLC injury was suspected in 10 patients (at 11 levels), of whom 8 (at 9 levels) were diagnosed intraoperatively with DLC injury, and 2 (at 2 levels) were excluded from the DLC injury. All the 43 patients were followed up for (54.7±10.7) months. By the ASIA grading at the last follow-up, 3 cases were grade C, 13 cases grade D, and 27 cases grade E. The JOA score at the last follow-up was (15.1±2.2) points. Both the 2 outcomes showed significant improvements compared with the preoperative values ( P<0.05). Conclusions:The clinical incidence of cervical hyperextension injury combined with MDLC injury is low, but relatively higher in the middle-aged and elderly patients. As the level of DLC injury is often inconsistent with the likely level of cervical spinal cord injury, surgical exploration of the DLC structure with suspected injury can reduce the rate of missed diagnosis and misdiagnosis.

Objective:To observe the clinical effect of retrograde distal tibial intramedullary nail fixation in the treatment of proximal ankle fracture of the distal tibia.Methods:A three-dimensional CT examination of 40 adult tibias was performed to measure anatomical indicators such as the posterior medial posterior torsion angle of the distal tibia, the height of torsion, and the height of the safety zone for nail placement. Based on the anatomy database of the human skeleton model, a retrograde distal tibial nail and its supporting instruments were developed in accordance with the anatomical characteristics of the distal tibia and the proximal ankle of Chinese people. From June 2019 to June 2023, a total of 25 patients with distal tibial proximal ankle fractures treated with retrograde intramedullary nail internal fixation in the 909th Hospital were retrospectively analyzed. There were 18 males and 7 females, aged 41.3±10.8 years (range, 22-65 years). The sample size was 1∶1 matched according to gender and age. Twenty-five patients with distal tibial proximal ankle fractures who underwent antegrade intramedullary nail fixation during the same period were matched, including 20 males and 5 females, aged 41.2±9.4 years (range 19-60 years). The reduction quality, postoperative Baird-Jackson score, American Orthopaedic Foot and Ankle Society (AOFAS) ankle and hindfoot score, ankle range of motion and complications were observed.Results:All patients were successfully operated and followed up for 14.4±3.5 months (range, 12-24 months). The intraoperative blood loss and hospitalization time in retrograde intramedullary nail group were 33.12±7.38 ml and 10.32±1.75 d, less than 49.04±10.22 ml and 13.16±2.69 d in antegrade intramedullary nail group, and the difference was statistically significant ( P<0.05). The reduction quality was excellent in 23 cases and good in 2 cases in the retrograde intramedullary nail group, and was excellent in 17 cases and good in 8 cases in the anterograde intramedullary nail group. The proportion of excellent reduction quality in the retrograde intramedullary nail group was higher than that in the anterograde intramedullary nail group, and the difference was statistically significant (χ 2=4.500, P=0.034). The Baird-Jackson score and AOFAS ankle and hindfoot score in the retrograde intramedullary nail group were 85.6±2.5 and 85.8±3.3 at 3 months after operation, lower than those at 1 year after operation 95.3±3.1 and 95.8±3.6, and the difference was statistically significant ( P<0.05). The Baird-Jackson score and AOFAS ankle and hindfoot score of the antegrade intramedullary nail group were 85.1±3.3 and 86.1±2.5 at 3 months after operation, lower than 95.2±2.7 and 94.9±3.5 at 1 year after operation, and the difference was statistically significant ( P<0.05). There was no significant difference in Baird-Jackson score and AOFAS ankle and hindfoot score between the two groups at 3 months and 1 year after operation ( P>0.05). At the last follow-up, there was no ankle stiffness, neurovascular injury, deep vein thrombosis, infection or breakage of internal fixation in the two groups. Conclusion:The treatment of distal tibial proximal ankle fractures with retrograde intramedullary nail fixation has satisfactory reduction quality, good postoperative function recovery, and is helpful for early postoperative rehabilitation.

Objective:To investigate the clinical efficacy of distal tibiofibular screw fixation combined with ligament repair for the treatment of ankle fracture accompanied with distal tibiofibular syndesmosis injuries.Methods:A retrospective cohort analysis was made on clinical data of 72 patients with ankle fracture accompanied with distal tibiofibular syndesmosis injuries admitted to 909th Hospital of Joint Service Support Force of PLA from September 2017 to September 2020, including 38 males and 34 females, aged 19-65 years [(42.5±12.2)years]. The fracture was type B in 30 patients, type C 1 in 29 and type C2 in 13 according to Danis-Weber classification. A total of 36 patients were treated by distal tibiofibular screw fixation combined with ligament repair (fixation+repair group) and 24 patients by distal tibiofibular screw fixation (fixation group). Operation time, intraoperative blood loss and hospital stay were recorded. Visual analogue scale (VAS), American Orthopedic Foot and Ankle Society (AOFAS) ankle hindfoot score and ankle range of motion (ROM) were determined at 1, 3 months postoperatively and at the final follow-up. Complications were documented. Results:All patients were followed up for 12-22 months [(15.9±2.2)months]. There were no significant differences in operation time, intraoperative blood loss and hospital stay between the two groups (all P>0.05). VAS in fixation+repair group was (3.1±1.0)points and (2.1±0.6)points at 1, 3 months postoperatively, significantly lower than (3.9±0.8)points and (2.6±0.8)points in fixation group (all P<0.05), but the score showed no significant difference between the two groups at the final follow-up ( P>0.05). AOFAS score in fixation+repair group was (64.7±4.0)points, (73.2±3.4)points and (87.2±3.4)points at 1, 3 months postoperatively and at the final follow-up, significantly higher than (60.1±4.9)points, (70.2±1.9)points and (84.1±2.6)points in fixation group (all P<0.05). There was no significant difference in the ROM between the two groups at 1 month postoperatively ( P>0.05), but the ROM at 3 months postoperatively and at the final follow-up in fixation+repair group [(44.4±2.9)° and (52.3±2.5)°, respectively] was significantly higher than that in fixation group [(41.4±2.7)° and (50.1±2.7)°, respectively] (all P<0.05). There was 1 patient with internal fixation loosening in fixation+repair group, with the incidence of complications of 3% (1/36). While the incidence of complications was significantly lhigher in fixation group [17%(6/36)], including 2 patients with re-separation of distal tibiofibular syndesmosis, 2 with internal fixation loosening and 2 with internal fixation breakage ( P<0.05). Conclusion:Compared with distal tibiofibular screw fixation, distal tibiofibular screw fixation combined with ligament repair for the treatment of ankle fracture accompanied with distal tibiofibular syndesmosis injuries is effective to early relieve ankle pain, improve ankle function and ROM, and reduce occurrence of complications.

Objective:To compare our self-designed elastic syndesmosis hook plate (ESHP) and suture-button technique in treatment of injury to the distal tibiofibular syndesmosis.Methods:A retrospective study was conducted of the 53 patients who had been treated at Military Orthopaedic Center, 909 Hospital of Joint Service Support Force of PLA for ankle fractures complicated with syndesmosis injury by ESHP or suture-button technique from March 2013 to March 2017. Of them, 28 were treated by ESHP (ESHP group: 15 males and 13 females aged from 26 to 60 years) and 25 by suture-button technique (suture-button group: 14 males and 11 females aged from 24 to 59 years). The 2 groups were compared in terms of syndesmosis fixation time, postoperative incision bleeding, hospital stay, and ankle dorsiflexion and plantarflexion and ankle function by Baird-Jackson scoring at 3, 6, 12 months after surgery. Postoperative complications were observed.Results:The 2 groups were comparable because there was no statistically significant deference in general data between the 2 groups ( P>0.05). Surgery went on uneventfully in all the patients. The syndesmosis fixation time [(9.7±2.2) min] and postoperative incision bleeding [(49.3±10.4) mL] in the ESHP group were significantly less than in the suture-button group [(16.2±1.4) min and (62.4±6.3) mL] ( P<0.05); the maximum plantar flexion (29.9°±1.3°) and Baird-Jackson scores (87.2±2.9) at 3 months after surgery in the ESHP group were significantly greater than in the suture-button group (22.8°±1.3° and 78.7±4.1) ( P<0.05). There were no significant differences between the 2 groups in hospital stay, maximum plantar flexion at postoperative 6 or 12 months, maximum dorsiflexion at postoperative 3, 6 or 12 months, or Baird-Jackson scores at postoperative 6 or 12 months (all P>0.05). This cohort was followed up for 12 to 14 months (average, 12.5 months). All fractures united during follow-up and all the implants were removed around postoperative 12 months. Follow-up within 12 months observed internal fixation failure caused by metal fatigue in one case in the ESHP group, and internal fixation irritation in one case, internal fixation failure in 2 cases and internal fixation sinking and osteolysis in one case in the suture-button group. Conclusion:Compared with the suture-button technique, treatment of injury to the distal tibiofibular syndesmosis with ESHP may lead to shorter fixation time, less postoperative bleeding and complications, and faster functional recovery of the ankle.

Objective To explore the perioperative management and surgical outcomes of fracture-dislocation of the upper cervical spine complicated with vertebral artery injury.Methods We retrospectively analyzed the clinical data of 19 patients diagnosed with fracture-dislocation of the upper cervical spine complicated with vertebral artery injury who had been treated at our department from January 2008 through December 2012.They were 14 males and 5 females,aged from 22 to 53 years (mean,35.2 years).All the patients had fractures of the atlas and/or axis,and disordered atlanto-axial relationship as well.According to Frankel grading system,8 cases were Grade D and 11 Grade E.The cervical posterior fixation with pedicle screws was adopted for all and hemostasis was conducted for those with bleeding from the broken vertebral artery.Their Frankel grade,Japanese Orthopedic Association (JOA) score and visual analogue scale (VAS) score were compared between preoperation and final follow-up.Results Intraoperative hemorrhage occurred in 2 patients from the injured vertebral artery.Hemostasis was achieved through direct tamponade with bone wax and gelatin sponge in one and through endovascular intervention after bleeding control by direct tamponade in another.Neither of them presented with symptoms of posterior circulation ischemia after operation.The mean operation time was 153.5 min,and the mean blood loss was 542.1 mL.All the patients were followed up for an average time of 28 months.Bony union was obtained in all after an average time of 13.5 weeks.Follow-ups revealed no ischemic stroke in this series.Symptoms of transient ischemic attack,like transient dizziness and blurred vision,appeared in 2 patients.At the final follow-up,all the patients were assessed as Frankel Grade E.Their mean JOA and VAS scores were significantly improved from 8.1 ± 1.2 and 7.0 ± 1.7 preoperatively to 12.7 ± 1.6 and 1.3 ± 1.2,respectively (P ＜ 0.05).Conclusions Angiography examination is routinely indicated for the patients with fracture-dislocation of the upper cervical spine perioperatively.Preoperative evaluation of the vertebral artery and its adjacent structures and effective intraoperative hemostasis can avoid uncontrollable bleeding during operation,reduce postoperative complications,and improve surgical outcomes.

OBJECTIVETo design a kind of internal fixation device to treat the syndesmosis injury.

METHODSThe elastic syndesmosis hook plate is made of medical stainless steel alloy, which is consisted of locking or common screw fixing hole of the tibial side for the head, tridentate fork like arc anatomical fibula side plate for the tail and serpentine elastic connecting body. By reduction of the joint of the lower tibia and fibula, the steel plate tail is fixed at the side of the fibula and the head is fixed at the side of the tibia for fixing the symphysis.

RESULTSThe design of elastic syndesmosis hook plate is reasonable, and the operation is convenient. There is no need to penetrate the substantia ossea and the plate has elastic micro-movement feature, the problem of internal fixation breakage and loosening is avoid in huge degree, so it is safe and reliable.

CONCLUSIONThe elastic syndesmosis hook plate is a new type medical apparatus of internal fixation of the symphysis, which is worthy of clinical popularization and application.

AIM:To observe the expression of nuclear factor-kappa B ( NF-κB) , N-methyl-D-aspartic acid re-ceptor 2B (NR2B) and inducible nitric oxide synthase (iNOS) in the spinal cord in a rat model of chronic constriction in-jury (CCI) of the sciatic nerve.METHODS:Fifty-six adult male Sprague-Dawley rats weighing 180~220 g were random-ly divided into sham group (n=8) and CCI group (n=48).The mechanical withdrawal threshold (MWT) and paw with-drawal latency (PWL) of the hind paws were measured 1 d before CCI and 1 d, 4 d, 7 d, 14 d and 21 d after surgery.The L4~L6 segment of the spinal cord was taken for determining the expression of NF-κB, NR2B and iNOS by RT-PCR and Western blotting.RESULTS:At 1 d, 4 d, 7 d, 14 d and 21 d after surgery, the MWT and PWL in CCI group were obviously lower than those in sham group .The expression of NF-κB, NR2B and iNOS at mRNA and protein levels in-creased significantly.Positive correlations were found between the mRNA expression of NF-κB and iNOS (r=0.842, P<0.05), and between the mRNA expression of NR2B and iNOS (r=0.833, P<0.05).CONCLUSION:The generation and maintenance of hyperalgesia in sciatic nerve injury rats may attribute to the activation of NF -κB and NR2B and concom-itant increase in iNOS .

To develop standard in vitro chondrosarcoma models, we synthesized three hydrogels (i. e., PDMAAm, PNaAMPS and PMETAC) and investigated the influence of Young's modulus, swelling ratio and electric charges on the behavior of chondrosarcoma cells seeded on the hydrogels, including morphology, adhesion and aggregation. Results showed that the morphology of chondrosarcoma cells at 6h was dependent on the charges of hydrogels; cells present spindle-shaped and round-shaped morphology on negative charged and neutral hydrogel, respectively, while no cells spreaded on positive charged hydrogel. Chondrosarcoma cells formed aggregates on neutral PDMAAm after further culture. The hydrogels can be synthesized easily and has the characteristics of ease at use with defined components, which holds great potential for developing standard chondrosarcoma models in vitro.
Bone Neoplasms ; pathology ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Chondrosarcoma ; pathology ; Humans ; Hydrogels ; chemistry ; pharmacology ; Methacrylates ; pharmacology ; Nylons ; pharmacology ; Static Electricity

A new production method of spraying dextran-based polyurethane external splints is introduced in this paper. The main raw material components are polymethylene polyisocyanate (PAPI), mixed with surfactants, acetone, soluble starch, catalyst, and so on. The splint is used for temporary fixing after fracture, with small size, light weight, easy portability, fine air perviousness, completely transparent to the X-ray. It also needs a shorter fixed operating time. It can not only fix quickly and effectively the vertebral column and limbs, but also significantly shorten the time of pre-hospital care.
Dextrans ; Equipment Design ; External Fixators ; First Aid ; instrumentation ; Fracture Fixation ; instrumentation ; Fractures, Bone ; surgery ; Polyurethanes ; Splints