Factors influencing utilization of communicable disease prevention and treatment education among the floating population: a cross-sectional study in China.

BACKGROUND: In China, communicable diseases (CD) have a negative impact on public health and economic stability. The influx of migrants, who make up a substantial portion of China's population and continue to rapidly expand, has seriously hampered CD prevention and control, needing special care. This study aimed to identify key factors influencing the utilization of CD prevention and treatment education (CDPTE) among the floating population. We are confident that the findings will highlight obstacles facing CDPTE among the migrants, and guide future development prevention, treatment of CD, and health education services. METHODS: A sample of migrants aged 15 years and above in 32 provincial units nationwide in 2018 was recruited by stratified multi-stage proportional to population size sampling (PPS). A structured questionnaire survey was conducted via face-to-face interviews. Subsequently, the Anderson health service utilization model was used as the theoretical framework and SPSS 26.0 statistical software was applied to analyze the data. The statistical description of the current situation of CDPTE acceptance and the chi-square test were used to compare the differences in CDPTE acceptance by different characteristics. Multivariate logistic regression was used to analyze key factors affecting the use of CDPTE among migrants. RESULTS: A total of 40.1% of the recruited participants reported receiving education on CD prevention and treatment, primarily delivered through traditional transmission media. Multilevel logistic regression results revealed that male migrants, aged 30-49 years, unmarried, with higher educational attainment, an average monthly household income of CNY 7,500-9,999 (or US$1,176-1,568), working more than 40 h per week, flowing into the Central and Western regions, migrated in the province, self-rated health, contracted family doctors and those with health records were more likely to receive CDPTE (p < 0.05). CONCLUSION: Our findings revealed unsatisfactory acceptance of education on CD prevention and treatment among migrants, implying that health education should be strengthened further. Publicity of relevant policies and works should be strengthened and specific interventions should be developed for key regions as well as vulnerable groups to enhance CDPTE. More financial support should also be provided to improve the quality of health education.

Incidences, causes and risk factors of unplanned reoperation within 30 days of craniovertebral junction surgery: a single-center experience.

PURPOSE: To investigate the incidences, causes, and risk factors for unplanned reoperation within 30 days of craniovertebral junction (CVJ) surgery. METHODS: From January 2002 to December 2018, a retrospective analysis of patients who underwent CVJ surgery at our institution was conducted. The demographics, history of the disease, medical diagnosis, approach and type of operation, surgery duration, blood loss, and complications were recorded. Patients were divided into the no-reoperation group and the unplanned reoperations group. Comparison between two groups in noted parameters was analyzed to identify the prevalence and risk factors of unplanned revision and a binary logistic regression was performed to confirm the risk factors. RESULTS: Of 2149 patients included, 34(1.58%) required unplanned reoperation after the initial surgery. The causes for unplanned reoperation contained wound infection, neurologic deficit, improper screw placement, internal fixation loosens, dysphagia, cerebrospinal fluid leakage, and posterior fossa epidural hematomas. No statistical difference was found in demographics between two groups (P > 0.05). The incidence of reoperation of OCF was significantly higher than that of posterior C1-2 fusion (P = 0.002). In terms of diagnosis, the reoperation rate of CVJ tumor patients was significantly higher than that of malformation patients, degenerative disease patients, trauma patients, and other patients (P = 0.043). The binary logistic regression confirmed that different disease, fusion segment (posterior) and surgery time were independent risk factors. CONCLUSIONS: The unplanned reoperation rate of CVJ surgery was 1.58% and the major causes were implant-related failures and wound infection. Patients with posterior occipitocervical fusion or diagnosed with CVJ tumors had an increased risk of unplanned reoperation.

Calcium phosphate cement promotes the stability of osteoporotic lumbar pedicle screw by enhancer-injecters with different number of holes.

BACKGROUNDS: This study aimed to compare whether Calcium phosphate cement (CPC) promotes the stability of osteoporotic lumbar pedicle screw by enhancer-injecters with different number of holes. METHODS: Through a self-designed bone cement injection device, the pedicle screw canal was strengthened with calcium phosphate bone cement, and divided into 4-hole group, 6-hole group, 8-hole group, straight pore group and the control group. The screw was inserted into the mechanical test module, the Maximum insertion torque and Maximum axial pull-out strength were recorded, and the distribution of calcium phosphate bone cement was analyzed by CT and X-ray. The data results were analyzed using SPSS19.0 statistical software package. RESULTS: The distribution of bone cement in different reinforcement groups was different and showed regularity. The bone cement in the 4-hole group was roughly located in the head 1/3 of the screw, the 6-hole group was located in the middle 1/3 of the screw, and the 8-hole group was located in the caudal 1/3 of the screw. Compared with the control group, the maximum axial pull-out force of screws in the lateral hole and full screw tunnel reinforcement group was significantly increased. There was no significant difference between the 4-hole, 6-hole and straight pore groups. There was no difference in the screw-in torque between the reinforcement groups, and they all increased significantly compared with the control group, and the difference was statistically significant. After the screw was pulled out, the interface between the bone cement and the polyurethane material was fractured, and a tight package was formed with the screw. CONCLUSIONS: Enhancer syringes with different hole numbers combined with CPC bone cement injection can significantly increase the maximum screw pull-out force. The 8-hole group has a smaller pull-out force and is relatively prone to leakage of reinforcing material, which lacks safety in use. The local reinforcement of 4-hole and 6-hole sheath can play a similar role to that of total nail tunnel reinforcement.

A novel bone cement injector augments Chinese osteoporotic lumbar pedicle screw channel: a biomechanical investigation.

BACKGROUND: The study aimed to (1) create a series of pedicle injectors with different number of holes on the sheath especially for the Chinese elderly patients and (2) further investigate the effects of the injectors on the augmentation of pedicle screw among osteoporotic lumbar pedicle channel. METHODS: This study used the biomechanical test module of polyurethane (Pacific Research Laboratory Corp, USA) to simulate the mechanical properties of human osteoporotic cancellous bone. The bone cement injectors were invented based on anatomical parameters of lumbar pedicle in Chinese elderly patients. Mechanical test experiments were performed on the bone cement injectors according to the three groups, namely, a local augmentation group, a full-length augmentation group, and a control group. The local augmentation group included three subgroups including 4-hole group, 6-hole group, and 8-hole group. All holes were laterally placed. The full-length augmentation group was a straight-hole injector. The control group was defined that pedicle screws were inserted without any cement augmentation. Six screws were inserted in each group and the maximum insertion torque was recorded. After 24 h of injecting acrylic bone cement, routine X-ray and CT examinations were performed to evaluate the distribution of bone cement. The axial pull-out force of screws was tested with the help of the material testing system 858 (MTS-858) mechanical tester. RESULTS: The bone cement injectors were consisted of the sheaths and the steel rods and the sheaths had different number of lateral holes. The control group had the lowest maximum insertion torque as compared with the 4-hole, 6-hole, 8-hole, and straight pore groups (P < 0.01), but the differences between the 4-hole, 6-hole, 8-hole, and straight pore groups were no statistical significance. The control group had the lowest maximum axial pull-out force as compared with the other four groups (P < 0.01). Subgroup analysis showed the 8-hole group (161.35 ± 27.17 N) had the lower maximum axial pull-out force as compared with the 4-hole group (217.29 ± 49.68 N), 6-hole group (228.39 ± 57.83 N), and straight pore group (237.55 ± 35.96 N) (P < 0.01). Bone cement was mainly distributed in 1/3 of the distal end of the screw among the 4-hole group, in the middle 1/3 and distal end of the screw among the 6-hole group, in the proximal 1/3 of the screw among the 8-hole group, and along the long axis of the whole screw body in the straight pore group. It might indicate that the 8-hole and straight-hole groups were more vulnerable to spinal canal cement leakage. After pullout, bone cement was also closely connected with the screw without any looseness or fragmentation. CONCLUSIONS: The bone cement injectors with different number of holes can be used to augment the pedicle screw channel. The pedicle screw augmented by the 4-hole or 6-hole sheath may have similar effects to the straight pore injector. However, the 8-hole injector may result in relatively lower pull-out strength and the straight pore injector has the risks of cement leakage as well as cement solidarization near the screw head.

Incidence and management of surgical site infection in the cervical spine following a transoral approach.

PURPOSE: Transoral approach can accomplish ventral decompression directly. However, surgical site infection (SSI) cannot be ignored. This paper aims to review the prevalence of infection and conduct advice for the treatment of SSI in the cervical spine following the transoral approach. METHODS: A retrospective analysis of patients with SSI after transoral atlantoaxial reduction plate (TARP) surgery was performed. SSI was classified into three kinds according to the modified American CDC criteria. RESULTS: 2.9% (17/581) patients who underwent TARP surgery, experienced SSI, of which five had superficial SSI (SI), eight had deep SSI (DI), and four had organ/space SSI (O/SI). The patients with SI underwent intravenous antibiotic treatment and were ultimately cured. Among the remaining 12 patients with DI and O/SI, 11 underwent reoperation for TARP system removal and subsequently one-stage posterior occipitocervical fixation, and one patient experienced infection two months post-operatively and died without receiving treatment. Among patients who underwent revision surgery, three experienced intracranial infection due to intra-operative dural tears, and continuous lumbar cerebrospinal fluid drainage and intrathecal injection of antibiotics were used as effective and appropriate treatments, with outcomes of one recovery and two deaths. All patients with SSI were begun on intravenous antibiotics with conversion to oral antibiotics. CONCLUSIONS: The incidence of SSI was 2.9% (17/581). Adequate peri-operative preparation, early diagnosis, and appropriate treatment of SSI require further research.

Continuous wound infusion of ropivacaine for the control of pain after thoracolumbar spinal surgery: a randomized clinical trial.

PURPOSE: A prospective randomized clinical trial was carried out to observe the analgesic efficacy of ropivacaine for postoperative pain following thoracolumbar spinal surgery. METHODS: Seventy-one patients with elective posterior thoracolumbar spinal surgery were randomly divided into two groups. Local group received 0.33 % ropivacaine by pump through the wound, and intravenous group received flurbiprofen axetil, pentazocine and palonosetron via intravenous pump. We evaluated the level of pain, the incidence of adverse reactions at 2, 4, 6, 12, 24, 36 and 48 h after operation, and the occurrence of chronic pain 3 months later. RESULTS: There were no significant differences in the pain level between the two groups. However, the incidence of nausea, vomiting and chronic pain was significantly lower in the local group. CONCLUSIONS: Our results showed that local infusion of ropivacaine achieved similar analgesic effects to intravenous delivery of analgesic drugs, but significantly reduced incidence of nausea, vomiting and chronic pain.

Transoral anterior revision surgeries for basilar invagination with irreducible atlantoaxial dislocation after posterior decompression: a retrospective study of 30 cases.

PURPOSE: To report the surgical techniques and clinical results of one-stage transoral anterior revision surgeries for basilar invagination (BI) with atlantoaxial dislocation (AAD) after posterior decompression. METHODS: From September 2008 to June 2012, 30 patients (16 men and 14 women) who had BI with irreducible atlantoaxial dislocation (IAAD) after posterior decompression underwent anterior revision surgeries in our department. Dynamic cervical radiographs, computed tomographic scans and magnetic resonance imaging were obtained pre- and postoperatively to assess the degree of AAD and ventral compression on the cervical cord. The JOA scoring system was used to evaluate the neurological status. The revision surgeries were conducted by anterior approach, using the transoral atlantoaxial reduction plate (TARP) system. RESULTS: The revision surgeries were successfully performed in all of the cases. The average follow-up duration was 16 months (range 6-39 months). For all of the cases, complete or more than 50 % reduction and decompression of C1-C2 were achieved. The cervicomedullary angle was improved by an average of 32.9°. Bone fusion was achieved within 3-6 months in all of the cases. Clinical symptoms were alleviated in 29 patients (96.7 %) and stabilised in 1 patient (3.3 %). No patients have developed recurrent or progressive atlantoaxial instability so far. CONCLUSION: Anterior revision surgeries using the TARP system achieved reduction, decompression and fixation of C1-C2 in one stage for BI with IAAD. This technique offers an effective, simple and safe method for the revision of such cases after posterior decompression.

Radiographic and clinical assessment on the accuracy and complications of C1 anterior lateral mass and C2 anterior pedicle screw placement in the TARP-III procedure: a study of 106 patients.

PURPOSE: To investigate the (1) radiographic and clinical accuracy of C1 anterior lateral mass screw (C1ALMS) and C2 anterior pedicle screw (C2APS) placement in the transoral atlantoaxial reduction plate (TARP)-III procedure, (2) screw insertion-associated clinical complications and (3) fusion status between C1 and C2. METHODS: Radiographic and clinical data were obtained from the electronic medical record system. Studies were carried out to assess the accuracy of C1ALMS and C2APS placement, the screw insertion-associated clinical complications and the fusion status between C1 and C2. Placement of the screws was assessed using the modified All India Institute of Medical Sciences outcome-based classification. RESULTS: Two-hundred and twelve C1ALMS and 207 C2APS in 106 patients were assessed. The ideal accurate rates were 92.0% (195) and 53.1% (110), and the acceptable accurate rates were 97.6% (207) and 87.0% (180), respectively. One patient died postoperatively due to C2 screw misplacement. There were no symptoms of neurologic and vertebral artery injuries in the rest of the patients. 102 patients (97.1%) achieved solid fusion between C1 and C2. No instrumentation failure due to delayed union or nonunion was observed. CONCLUSION: C1ALMS placement in TARP-III procedures appears to be safe. The cortical breach rate of C2APS is high though clinically the neurovascular complication rate is similar to that of posterior atlantoaxial procedures. Advanced navigation strategies may help improve the accuracy of C2APS placement and decrease potential complications.

Treatment of basilar invagination with atlantoaxial dislocation: atlantoaxial joint distraction and fixation with transoral atlantoaxial reduction plate (TARP) without odontoidectomy.

PURPOSE: Although direct transoral decompression and one-stage posterior instrumentation can obtain satisfactory cord decompression for the treatment of basilar invagination with atlantoaxial dislocation, surgical injuries run high as combinative anterior-posterior approaches were necessary. Furthermore, the complications will rise notably when involvement of dens and/or clivus in the decompression necessitates relatively complicated surgical techniques. First initiated in 2005, transoral atlantoaxial reduction plate (TARP) works as an internal fixation for the treatment of basilar invagination with irreducible atlantoaxial dislocation. Therefore, this article aimed to describe several operative experiences about this approach, which has delivered successful decompression, fixation and fusion. METHODS: 21 consecutive patients with basilar invagination underwent the TARP operation. The pre- and postoperative medulla-cervical angles were measured and compared. The JOA scores of spinal cord function were calculated pre- and post-operatively. 20 cases (20/21) were followed up to average 12.5 months. RESULTS: Symptoms of all the 20 cases were relieved in different degrees. The postoperative imaging showed the odontoid processes obtained ideal reduction and the internal fixators were all in good position. The medulla-cervical angle was correctd from an average (± standard deviation) 128.7° + 11.9° (n = 20) before surgery to 156.5° + 8.1° (n = 20) after surgery (P < 0.01). The average preoperative and postoperative Japaneses Orthopedic Association scores were 11.25 (n = 20) and 15.9 (n = 20), respectively, indicating 76 % improvement. Screw-loosening was observed in one patient due to severe osteoporosis. After a revised operation with a TARP in another size, the neurological symptoms showed no obvious improvements. Then the treatment was terminated. CONCLUSIONS: The TARP operation and intra-operative traction could reduce the odontoid process superiorly migrating into the foramen magnum, directly ease the ventral compression of spinal cord, and fix the reduced atlantoaxial joints through a single transoral approach without the need of a posterior operation. In this stury, 21 patients were evaluated and 20 did well with TARP operation. The preliminary clinical result was satisfactory.

Clinical application of computer-aided design-rapid prototyping in C1-C2 operation techniques for complex atlantoaxial instability.

STUDY DESIGN: This is a retrospective clinical study. OBJECTIVE: To evaluate the clinical efficacy of computer-aided design-rapid prototyping (CAD-RP) techniques in surgical treatments for atlantoaxial instability (AAI). SUMMARY OF BACKGROUND DATA: The complexity of the upper cervical anatomic structures makes the procedures for the treatment of AAI particularly challenging for surgeons. The present study represents a series of C1-C2 surgery for AAI aided by CAD-RP. METHODS: A total of 49 patients (21 men and 28 women) with AAI were treated in our department. According to the use of the CAD-RP technique, the patients were divided into RP group and No RP group. Preoperative CT scans of the upper cervical spine were performed for each patient. For the RP group, physical RP models of the upper cervical spine were manufactured from the 3-dimensional CT data and were used for intraoperative guidance. Personalized surgeries were performed for each case of the 2 groups. The screw malposition rate, frequency of using intraoperative fluoroscopy, operation time, blood loss, and improvement of neurological function were compared between the 2 groups. The mean follow-up duration was 32 months (range, 24-50 mo). RESULTS: The operations were successfully performed in 48 cases expect for 1 case in the No RP group. A total of 204 screws were placed. The intraoperative fluoroscopy frequency and operation time were significantly lower in the RP group than that in the No RP group in both posterior and anterior approaches, whereas the screw malposition rate showed no difference between the 2 groups for both approaches. After the operation, 48 cases achieved satisfactory decompression of the cervical cord and repositioning of the atlantoaxial spine. During follow-up, 47 cases presented improvements in the spinal nerve function within 2 years. CONCLUSIONS: CAD-RP techniques have significant benefits for surgeons providing personalized treatments for AAI, especially cases with complicated deformities.

A Novel Stepwise Technique for Safe and Effective Transoral Release of Irreducible Atlantoaxial Dislocation: A Retrospective Study of 201 Cases.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: To verify the clinical efficacy of a novel transoral stepwise release technique (TSRT) for the treatment of irreducible atlantoaxial dislocations (IAAD). SUMMARY OF BACKGROUND DATA: Anterior release for IAAD remains challenging, with a 3.2 times higher complication rate than posterior release. However, there are some patients who cannot achieve successful reduction from a posterior approach and require the higher-risk anterior release. Our work presents a novel anterior release technique that aims to minimize iatrogenic injury and associated complications from an anterior release. MATERIALS AND METHODS: IAAD cases who were treated with TSRT were retrospectively studied. Primary outcomes included fusion rate, complications, and neurological function over the course of a minimum 1-year follow-up. Radiographic differences between preoperative and postoperative imaging were also considered. A preoperative prediction model for the actual release grade was developed using multivariate logistic regression based on demographic factors and the craniovertebral abnormalities identified on preoperative images, evaluating the need for higher-grade TSRT release. RESULTS: We included 201 IAAD cases, with 42% (84/201) demonstrating degeneration of the atlantoaxial joint or anterior-hook-like dens. The reduction was achieved in all cases, with 80% (160/201) of cases only requiring relatively low-grade or grade I types TSRT release. Degeneration of the atlantoaxial joint was significantly associated with the need for higher-grade TSRT release (odds ratio:16.68, CI: 2.91-94.54, P = 0.002). The overall complication rate was 4.5% (9/201). Over the course of follow-up, the fusion rate reached 98.5%, and the American Spinal Injury Association and Japanese Orthopedic Association scores were significantly improved to 97.28 and 16.25 ( P < 0.01 and P < 0.01), respectively. CONCLUSION: This study demonstrated that our novel TSRT anterior release technique demonstrated complication rates similar to those published in the literature for posterior release. TSRT can be used as an alternative to posterior release techniques for refractory cases or when a posterior approach is not considered viable.

Risk factors for nonspecific low-back pain in Chinese adolescents: a case-control study.

OBJECTIVES: The objective of this study was to gain a basic understanding of the influential factors for nonspecific low-back pain (LBP) among adolescents of southern China. DESIGN: The study was designed as a school-based case control study. SETTING: Nonspecific LBP is a common health problem in adolescence. Although some behaviors and socio-demographic factors are believed to contribute to the disorder, influential factors of LBP remain undefined. Moreover, until now there is no available information of influential factors for LBP in Chinese adolescents. SUBJECTS: A total of 1,214 adolescents were involved in the study, including 607 cases with nonspecific LBP and 607 controls without history of nonspecific LBP. OUTCOME MEASURES: A self-administered questionnaire was designed for epidemiological survey to investigate the risk factors for nonspecific LBP. All cases and controls were investigated for their family histories of nonspecific LBP, physical activities, sedentary activities, schoolbag weights, school performances, living conditions, and etc. METHOD: A 1:1 matched case-control study was conducted on 1,214 adolescents from an elementary school and a secondary school in Guangzhou City, southern China. RESULTS: Family history (odds ratio [OR] 2.57, 95% confidence interval [CI] 1.85-3.58), long duration of carrying schoolbag (OR 1.38, 95% CI 1.11-1.72) and rest position between classes (OR 1.18, 95% CI 1.01-1.39) were positively correlated with self-reported nonspecific LBP. Students regularly playing basketball (OR 1.58, 95% CI 1.09-2.30) was found to be significantly more likely to have LBP. Also, students who feel schoolbag uncomfortable (OR 1.38, 95% CI 1.11-1.72) was found to experience more LBP. CONCLUSIONS: Family history, feeling schoolbag uncomfortable, duration of schoolbag carrying, basketball playing and rest position between classes are the major risk factors for nonspecific LBP in adolescents.

Classification and Surgical Treatment of Developmental Spinal Canal Stenosis at Atlas Level: A 15-Case Study.

STUDY DESIGN: A retrospective study. OBJECTIVE: Investigate the diagnosis and surgery strategy for treatment of development spinal canal stenosis (DSSA) at atlas plane based on computerized tography (CT) image characters. SUMMARY OF BACKGROUND DATA: The occurrence of spinal canal stenosis in the atlas plane is relatively rare compared with lower cervical. METHODS: Fifteen patients diagnosed with DSSA were included from 2014 to 2018. They are divided into four subgroups based on the character of CT images: group I (small size atlas), group II (hypertrophy of posterior arch of the atlas [PAA]), group III (incurved of PAA), and group IV (hypertrophy odontoid). RESULTS: There are type I 7, type II 3, type III 2, and group IV 3 in the 15 cases. All the patients received different surgery procedures respectively: (1) posterior arch osteotomy were performed for group I/III//IV without atlantoaxial dislocation, (2) posterior arch resect and replantation were performed for group II, (3) occipital cervical fixation and fusion were added to the patients with associated atlantoaxial dislocation (AAD), (4) a new method of odontoid reduce and atlantoaxial fixation by transoral approach were performed for group IV with associated AAD. All cases underwent surgery successfully which included posterior occipitocervical fixation (OCF) + posterior arch resection (PAR) eight cases, PAR four cases, posterior arch remodeling and re-implantation (PARR) two cases, and Dens remodeling + trans-oral anterior reduction and plate fixation (DR+TARP) one case without severe complications. All patients show different improvement in the symptoms. Japanese orthopaedic association score improved from 9.2 to 14.7 in 1 year follow-up. CONCLUSION: DSSA could be easily diagnosed and divided into four subgroups according to the character of CT image, corresponding surgery strategy could receive a fine clinical result.Level of Evidence: 4.

Determination of antibacterial properties and cytocompatibility of silver-loaded coral hydroxyapatite.

In this study, silver-loaded coral hydroxyapatites (SLCHAs) were used as scaffolds for bone tissue engineering. The SLCHAs were prepared by surface adsorption process and ion-exchange reaction between Ca(2+) of coral hydroxyapatite (CHA) and Ag(+) of silver nitrate with different concentrations at room temperature. The properties of the composite SLCHAs were investigated by inductively coupled plasma-atomic emission spectrometry (ICP-AES), scanning electron microscropy (SEM) equipped with backscattered electron detector (BSE), and energy-dispersive X-ray spectrometer (EDS). The SEM images showed that the morphology of the SLCHAs depended on the content of Ag(+), and the silver ions were uniformly distributed on the surface of SLCHAs. The ICP-AES results demonstrated that the silver content of the SLCHAs decreased along with the decrease of the concentration of silver nitrate. The SLCHAs were found effective against Escherichia coli and Staphylococcus aureus by antibacterial test. Mouse embryonic pre-osteoblast cells (MC3T3-E1) were used to test the cytocompatibility of SLCHAs, CHA, and pure coral. Cell morphology and cell proliferation were studied with SEM, laser scanning confocal microscope (LSCM), and MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide) assay after 1, 3, and 5 days of culture. The results indicated the cell morphology and proliferation on the scaffolds of Ag(+) (13.6 microg/ml)/CHA and Ag(+) (1.7 microg/ml)/CHA were better than that on Ag(+) (170 microg/ml)/CHA. In addition, adhesion of MC3T3-E1 on the scaffolds showed that the confluent cells showed fusiform shape and arranged tightly on the scaffolds. All the results showed that the antibacterial SLCHAs would have potential clinical application as the scaffolds for bone tissue engineering.

[Diagnosis and treatment for complicated atlantoaxial dislocation].

OBJECTIVE: To explore the clinical characteristics and treatment methods for complicated atlantoaxial dislocation. METHODS: A retrospective evaluation was done to summarize and analyze the clinical characteristics and complicated factors of 54 patients with complicated atlantoaxial dislocation who could not to be treated effectively by using conventional therapy in our hospital from February 2005 to October 2008. According to different complicated factors, different treatment methods mainly including transoral atlantoaxial reduction plate-III (TARP-III) operation, decompression procedure with deep grinding guided by computer aided design-rapid prototyping (CAD-RP), screw placement technique with CAD-RP guide plate and extensile approach surgery were performed. RESULTS: The average follow-up period was 24 months. Among 54 cases, 48 cases achieved immediate anatomic reduction completely and 6 cases almost achieved anatomical reduction. All the compressed spinal cords were decompressed sufficiently. The decompression rate was 86.0% and the improvement rate of nerve function was 77.8%. Two cases suffered postoperative intracranial infection. CONCLUSION: Some cases of complicated atlantoaxial dislocation can be effectively treated by using TARP-III operation, decompression procedure with deep grinding guided by CAD-RP, individualized screw placement technique with CAD-RP guide plate and extensile approach surgery.

[Treatment of tuberculosis in craniovertebral junction].

OBJECTIVE: To investigate the method of treating tuberculosis in the craniovertebral junction and its effectiveness. METHODS: The clinical data of 18 patients with tuberculosis in the craniovertebral junction between July 2010 and January 2019 was analyzed retrospectively. There were 14 males and 4 females, aged 21 months to 75 years (median, 35 years). The disease duration ranged from 2 weeks to 60 months (median, 4 months), and the affected segment was C 0-C 3. Preoperative visual analogue scale (VAS) score was 6.7±1.5 and the Japanese Orthopaedic Association (JOA) score was 16.1±1.8. The American Spinal Cord Injury Association (ASIA) grading system was applied to classify their neurological functions, according to which there were 6 cases of grade D and 12 cases of grade E. Among 18 patients, 4 patients underwent conservative treatment, 1 patient removed tuberculosis via transoral approach, 1 patient removed tuberculosis via posterior cervical approach, and 12 patients removed tuberculosis via transoral approach immediately after posterior cervical (atlantoaxial or occipitalcervical) fusion and internal fixation. The VAS score, ASIA grading, and JOA score were applied to evaluate effectiveness. X-ray film, CT, and MRI were taken after treatment to evaluate the tubercular recurrence, cervical stability, and bone healing. RESULTS: All the patients were followed up 3 to 42 months (median, 12 months). At 3 months after treatment, the VAS score was 1.7±1.0, showing significant difference when compared with preoperative score ( t=15.000, P=0.000); and the JOA score was 16.7±1.0, showing no significant difference when compared with preoperative score ( t=1.317, P=0.205). According to ASIA grading, 6 patients with grade D before treatment had upgraded to grade E after treatment, while the remaining patients with grade E had no change in grading. The imaging examinations showed the good stability of the cervical spine. All patients had complete tuberculosis resection and no recurrence, and the patients who underwent internal fixation via posterior cervical approach achieved atlantoaxial or occipitalcervical bone fusion. CONCLUSION: On the premise of regular chemotherapy, if there is no huge abscess causing dysphagia or dyspnea, atlantoaxial instability, and neurological symptoms, patients can undergo conservative treatment. If not, however, the transoral approach can be used to completely remove the tuberculosis lesion in the craniovertebral junction. One-stage debridement via transoral approach combined with posterior cervical fusion and internal fixation can achieve satisfactory effectiveness.

[An application of posterior cervical and transoral approaches to treating primary malignant osseous tumors in craniovertebral junction].

OBJECTIVE: To investigate the surgical method for primary malignant osseous tumors in the craniovertebral junction (CVJ) and its effectiveness. METHODS: The clinical data of 7 patients with primary malignant osseous spinal tumors in CVJ, which collected between September 2010 and April 2019, were retrospectively analyzed. There were 5 males and 2 females, aged 23 to 75 years (median, 56 years). All patients were diagnosed as chordoma in 4 cases, plasmacytoma in 2 cases, and fibrosarcoma in 1 case. The disease duration ranged from 0.7 to 36.0 months, with an average of 12.2 months. Lesion location: 1 case of C 0, 1, 3 cases of C 2, 1 case of C 1, 2, 1 case of C 2, 3, and 1 case of C 0-2. Preoperative visual analogue scale (VAS) score was 6.7±2.1, the Japanese Orthopaedic Association (JOA) score was 15.6±2.4. According to American Society of Spinal Cord Injury (ASIA) grading system, there was 1 case of grade C, 1 case of grade D, and 5 cases of grade E. According to Enneking stage of spinal malignant tumor, there was 1 case of stage ⅠB, 2 cases of stage ⅡB, and 4 cases of stage Ⅲ. According to Weinstein-Boriani-Biagini (WBB) stage, there was 1 case of 5-8/A-D, 1 case of 4-9/A-D, 1 case of 6-7/B-D, 1 case of 6-7/A-D, 2 cases of 1-12/A-D, and 1 case of 3-10/A-D. All these patients were treated with tumor extended resection, bone graft fusion, and internal fixation via posterior cervical approach, as well as tumor (stage Ⅰ or stage Ⅱ) boundary resection via transoral or submandibular approach. Meanwhile, anterior reconstructive fusion was procedured with bone grafting Cage needed to place the internal fixation. RESULTS: The operation time was 307-695 minutes (mean, 489.57 minutes), and the intraoperative blood loss was 400-2 000 mL (mean, 1 107.14 mL). There was no intraoperative injury in vertebral artery and spinal cord or any related postoperative complications, including incision infection, intracranial infection, and pulmonary infection. All the patients were followed up 3-57 months (mean, 21 months). Postoperative X-ray film and CT showed that the internal fixation screw was firm and in a satisfactory position, and the bone graft was fused at 3-6 months after operation. Symptoms such as neck pain, limb numbness, and fatigue relieved to different degrees after operation. At 3 months after operation, the VAS score improved to 1.7±0.8 ( t=7.638, P=0.000); while the JOA score improved to 16.1±1.5, but no significant difference was found when compared with preoperative score ( t=1.549, P=0.172). According to ASIA grading system, 1 patient with grade C had upgraded to grade D after operation, while the remaining patients had no change. There were 4 cases of recurrence after operation, in which those patients were with high malignancy of tumors before the first surgery. Their tumors also affected a wide range of slope or surrounding soft tissues and could not be completely removed. Among the 4 cases, 1 patient underwent transoral tumor removal operation again, while the other 3 cases gave up further treatment. There was no recurrence among the remaining 3 cases. CONCLUSION: Primary malignant osseous tumors in the CVJ can be completely exercised via means of trabsoral or submandibular approach. Meanwhile the anterior reconstruction can be achieved by placing special Cage specimen. These two methods together with postoperative adjuvant treatments such as radiotherapy and chemotherapy can improve the survival time of patients and reduce tumor recurrence.

[An observation on risk of infection in treatment of craniovertebral junction disorders by transoral approach operation].

OBJECTIVE: To study the changes of bacterial flora after a series of preoperative oral disinfection and the postoperative recovery of patients with craniovertebral junction disorders who were treated with transoral approach operations. And to provide a theoretical basis for the prevention of postoperative complications such as infection. METHODS: The clinical data of 20 cases with craniovertebral junction disorders and treated with transoral approach operations between October 2009 and May 2010 were analyzed. There were 8 males and 12 females, aged 2-66 years (median, 34.5 years). According to the classification of American Spinal Injury Association (ASIA)，there were 4 cases of grade B, 8 of grade C, 6 of grade D, and 2 of grade E. The Japanese Orthopedic Association (JOA) score was 10.3±3.0. The mucosa samples of the posterior pharyngeal wall were sent for bacteria culture. These samples were collected by sterile cotton swabs at four crucial points including 3 days before operation/before gargling (T1), 3 days after continuous gargling by chlorhexidine acetate/after anesthesia intubation on the day of operation (T2), after intraoperative cleaning and washing of the mouth (T3), and after intraoperative iodophor immersion for 5-10 minutes (T4). The microflora was stained by means of smear and further counted after an investigation by microscope. The ASIA classification and the JOA scores were applied to evaluate the postoperative nerve function of the patients. A regular reexamination of cervical vertebra with X-ray film, CT, and MRI was conducted after operation to evaluate the reduction of atlantoaxial dislocation, internal fixation position, bone graft fusion, inflammatory lesion, and tumor resection in the craniovertebral junction. RESULTS: After a series of oral disinfection, the mucosa of the posterior pharyngeal wall of all the patients was in a sterile state, which was considered as type Ⅰ incision. All these 20 patients were treated with successful operations, without any intraoperative injury in vertebral artery and spinal cord, or any postoperative complications such as plate loosening, incision infection, or intracranial infection. All the patients were followed up 3-23 months, with an average of 5.15 months. The symptoms such as neck pain, limb numbness and weakness, neural symptoms, etc. were improved to different degrees after operation. The JOA score was improved to 13.4±1.9 at 3 months after operation, showing significant difference when compared with preoperative score ( t=8.677, P=0.000); and the atlantoaxial joints had been fused. At last follow-up, the ASIA grades were improved when compared with those before operation. CONCLUSION: It is safe and effective to cut the posterior pharyngeal muscle layer and implant internal fixation by means of transoral approach in the treatment of craniovertebral junction disorders.

Management of pediatric patients with irreducible atlantoaxial dislocation: transoral anterior release, reduction, and fixation.

OBJECTIVE: Although transoral atlantoaxial reduction plate (TARP) surgery has been confirmed to be safe and effective for adults who have irreducible atlantoaxial dislocation (IAAD) with or without basilar invagination or upper cervical revision surgery, it is rarely used to treat these disorders in children. The authors of this study aimed to report on the use of the anterior technique in treating pediatric IAAD. METHODS: In this retrospective study, the authors identified 8 consecutive patients with IAAD who had undergone surgical reduction at a single institution in the period between January 2011 and June 2104. The patients consisted of 5 males and 3 females. Three had os odontoideum, 2 had basilar invagination, and the other 3 experienced atlantoaxial rotatory fixed dislocation (AARFD). They were all treated using transoral anterior release, reduction, and fusion with the TARP. Preoperative and postoperative CT scans and MR images were obtained. American Spinal Injury Association (ASIA) Impairment Scale grades were determined. RESULTS: All symptoms were relieved in all 8 patients but to varying degrees. Intraoperative loose reduction and fixation of C1-2 were achieved in one stage. The 4 patients with preoperative neurological deficits were significantly improved after surgery, and their latest follow-ups indicated that their ASIA Impairment Scale grades had improved to E. Postoperative pneumonia occurred in 1 patient but was under complete control after anti-infective therapy and fiber optic-guided sputum suction. CONCLUSIONS: One-stage transoral anterior release, reduction, and fixation is an effective, reliable, and safe means of treating pediatric IAAD. The midterm clinical results are satisfactory, with the technique eliminating the need for interval traction and/or second-stage posterior instrumentation and fusion.

[Application of posterior approach for atlantoaxial subdural extramedullary nerve sheath tumors].

OBJECTIVE: To investigate the procedure and effectiveness of posterior approach for operation of atlantoaxial subdural extramedullary nerve sheath tumors. METHODS: Between January 2012 and March 2017, 9 patients with atlantoaxial subdural extramedullary nerve sheath tumors were treated, including 7 males and 2 females, aged 25-62 years (mean, 45.4 years). There were 8 cases of neurinoma and 1 case of neurofibroma. The tumors were located at C1 in 1 case and C1, 2 in 8 cases. The disease duration ranged from 5 to 120 months, with an average of 45.9 months. The neural function was rated as grade D in 8 cases and grade E in 1 case according to the American Spinal Injury Association (ASIA) grading system. The Japanese Orthopaedic Association (JOA) score was 12.8±2.5. All patients underwent posterior cervical surgery. The laminae were replanted and fixed in 2 cases. The atlantoaxial or occipitocervical axis was not fixed in all patients. RESULTS: The operation time was 90-343 minutes, with an average of 179.2 minutes. The intraoperative blood loss was 50-1 000 mL, with an average of 335.6 mL. No relevant complication occurred after operation. All patients were followed up 6-21 months (mean, 11.1 months). The postoperative X-ray films showed the good stability of the cervical spine. All patients had complete tumor resection and no recurrence. The replanted laminae achieved fusion and the internal fixation was firm. According to ASIA grading system, 3 patients of preoperative ASIA grade D had upgraded to grade E at 3 months after operation, while the remaining patients had no change in grading. The JOA score was 15.1±1.4 at 6 months after operation, which was significantly improved when compared with that before operation (t=4.221, P=0.003). CONCLUSION: The atlantoaxial subdural extramedullary nerve sheath tumor (including the ventral tumor) can be removed completely via posterior approach. The axis lamina can be replanted and fixed with the small titanium plate or lamina screw when necessary, and the atlantoaxial or occipitocervical fixation was not needed.