1.Processing technology of calcined Magnetitum based on concept of QbD and its XRD characteristic spectra.
De-Wen ZENG ; Jing-Wei ZHOU ; Tian-Xing HE ; Yu-Mei CHEN ; Huan-Huan XU ; Jian FENG ; Yue YANG ; Xin CHEN ; Jia-Liang ZOU ; Lin CHEN ; Hong-Ping CHEN ; Shi-Lin CHEN ; Yuan HU ; You-Ping LIU
China Journal of Chinese Materia Medica 2025;50(9):2391-2403
Guided by the concept of quality by design(QbD), this study optimizes the calcination and quenching process of calcined Magnetitum and establishes the XRD characteristic spectra of calcined Magnetitum, providing a scientific basis for the formulation of quality standards. Based on the processing methods and quality requirements of Magnetitum in the Chinese Pharmacopoeia, the critical process parameters(CPPs) identified were calcination temperature, calcination time, particle size, laying thickness, and the number of vinegar quenching cycles. The critical quality attributes(CQAs) included Fe mass fraction, Fe~(2+) dissolution, and surface color. The weight coefficients were determined by combining Analytic Hierarchy Process(AHP) and the criteria importance though intercrieria correlation(CRITIC) method, and the calcination process was optimized using orthogonal experimentation. Surface color was selected as a CQA, and based on the principle of color value, the surface color of calcined Magnetitum was objectively quantified. The vinegar quenching process was then optimized to determine the best processing conditions. X-ray diffraction(XRD) was used to establish the characteristic spectra of calcined Magnetitum, and methods such as similarity evaluation, cluster analysis, and orthogonal partial least squares-discriminant analysis(OPLS-DA) were used to evaluate the quality of the spectra. The optimized calcined Magnetitum preparation process was found to be calcination at 750 ℃ for 1 h, with a laying thickness of 4 cm, a particle size of 0.4-0.8 cm, and one vinegar quenching cycle(Magnetitum-vinegar ratio 10∶3), which was stable and feasible. The XRD characteristic spectra analysis method, featuring 9 common peaks as fingerprint information, was established. The average correlation coefficient ranged from 0.839 5-0.988 1, and the average angle cosine ranged from 0.914 4 to 0.995 6, indicating good similarity. Cluster analysis results showed that Magnetitum and calcined Magnetitum could be grouped together, with similar compositions. OPLS-DA discriminant analysis identified three key characteristic peaks, with Fe_2O_3 being the distinguishing component between the two. The final optimized processing method is stable and feasible, and the XRD characteristic spectra of calcined Magnetitum was initially established, providing a reference for subsequent quality control and the formulation of quality standards for calcined Magnetitum.
X-Ray Diffraction/methods*
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Drugs, Chinese Herbal/chemistry*
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Quality Control
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Particle Size
2.Early results and indications of Stand-alone oblique lateral interbody fusion in lumbar lesions.
Zhong-You ZENG ; Xing ZHAO ; Wei YU ; Yong-Xing SONG ; Shun-Wu FAN ; Xiang-Qian FANG ; Fei PEI ; Shi-Yang FAN ; Guo-Hao SONG
China Journal of Orthopaedics and Traumatology 2025;38(5):454-464
OBJECTIVE:
To summarize the early clinical results and safety of Stand-alone OLIF application of lumbar lesions, and explored its surgical indications.
METHODS:
Total of 92 cases of lumbar spine lesions treated with Stand-alone OLIF at two medical centers from October 2014 to December 2018 were retrospectively analyzed, including 30 males and 62 females with an average age of (61.20±12.94) years old ranged from 32 to 83 years old. There were 20 cases of lumbar spinal stenosis, 15 cases of lumbar disc degeneration, 11 cases of lumbar degenerative spondylolisthesis, 6 cases of discogenic low back pain, 7 cases of giant lumbar disc herniation, 13 cases of primary lumbar discitis, 6 cases of adjacent vertebral disease after lumbar internal fixation surgery, and 14 cases of degenerative lumbar scoliosis. Pre-operative dual energy X-ray bone density examination 31 cases' T-values ranged from -1 to -2.4, 8 cases' T-values ranged from -2.5 to -3.5, and the rest had normal bone density. The number of fusion segments: 68 cases of single segment, 9 cases of two segment, 12 cases of three segment , and 3 cases of four segment. Fusion site:L1,2 1 case, L2,3 4 cases, L3,4 10 cases, L4,5 53 cases, L2,3-L3,4 3 cases, L3,4-L4,5 6 cases, L1,2L2,3L3,4 1 case, L1,2L3,4L4,5 1 case, L2,3L3,4L4,5 10 cases, L1,2L2,3L3,4L4,5 3 cases. The clinical results and imaging results of this group of cases were observed, as well as the complications.
RESULTS:
The surgical time ranged from 40 to 140 minutes with an average of (60.92±27.40) minutes. The intraoperative bleeding volume was 20 to 720 ml with an average of (68.22±141.60) ml. The patients had a follow-up period of 6 to 84 months with an average of (38.50±12.75) months. The height of the intervertebral space recovered from (9.23±1.94) mm in preoperative to (12.68±2.01) mm in postoperative, and (9.11±1.72) mm at the last follow-up, there was a statistically significant difference(F=6.641, P=0.008);there was also a statistically significant difference between the postoperative and preoperative height of the intervertebral space(t=9.27, P<0.000 1);and there was also a statistically significant difference (t=10.06, P<0.000 1) between the last follow-up and postoperative height of the intervertebral space. At the last follow-up, cage subsidence grading was as follows:level 0 in 69 cases (76 segments), levelⅠin 17 cases (43 segments), level Ⅱin 5 cases (14 segments), and level Ⅲ in 1 case (1 segment);according to the number of segments, normal subsidence accounts for 56.72%, abnormal subsidence accounts for 43.28%. Bone mineral desity of normal subsidence groups was -0.50±0.07 whinch was better than that the abnormal subsidence groups -2.10±0.43, and the difference was statistically significant(χ2=2.275, P=0.014). As well as there was a statistically significant difference in the patient's VAS of backache from (6.28±2.11) in preoperative to (1.48±0.59) in last follow-up(t=8.56, P<0.05). The ODI recovered from (36.30±7.52)% before surgery to (10.20±2.50)% at the last follow-up, with a statistically significant difference (t=7.79, P<0.000 1). Complications involved 4 cases of intraoperative vascular injury, 21 cases of endplate injury, and 4 cases of combined vertebral fractures. The incision skin has no necrosis or infection. There were 4 cases of left sympathetic chain injury, 4 cases of transient left hip flexion weakness, 2 cases of left thigh anterolateral numbness with quadriceps femoris weakness, and 1 case of incomplete intestinal obstruction;8 cases were treated with posterior pedicle screw fixation due to fusion cage settlement accompanied by stubborn lower back pain, and 6 cases were treated with fusion cage settlement and lateral displacement. According to the actual number of cases, there were 38 complications, with an incidence rate of 41.3%.
CONCLUSION
The application of Stand alone OLIF in lumbar spine disease fusion has achieved good early results, with obvious clinical advantages, but also there are high probability of complications. It is recommended to choose carefully. It is necessary to continuously summarize and gradually clarify and complete the surgical indications and specific case selection criteria.
Humans
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Male
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Female
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Middle Aged
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Spinal Fusion/methods*
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Lumbar Vertebrae/injuries*
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Aged
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Adult
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Retrospective Studies
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Aged, 80 and over
4.Targeting IRG1 in tumor-associated macrophages for cancer therapy.
Shuang LIU ; Lin-Xing WEI ; Qian YU ; Zhi-Wei GUO ; Chang-You ZHAN ; Lei-Lei CHEN ; Yan LI ; Dan YE
Protein & Cell 2025;16(6):478-483
5.Characteristics of abnormal coronary aorta origin in adults and cause analysis of missed diagnosis by transthoracic echocardiography
Si-Yang ZUO ; Sen LI ; You-Xiang KANG ; Xiao-Ling ZHAO ; Li-Xing WANG ; Rui CHEN ; Zhi-Yu FENG
Chinese Medical Equipment Journal 2024;45(1):71-75
Objective To analyze the characteristics of adult anomalous aortic origin of coronary artery(AAOCA)and the causes of missed diagnosis by transthoracic echocardiography(TTE)so as to facilitate TTE in diagnosing adult AAOCA.Methods A total of 37 adult patients with AAOCA diagnosed by non-invasive coronary CT angiography(CCTA)and/or invasive coronary angiography(ICA)were selected as research samples at some hospital from January 2019 to December 2022,and their clinical symptoms and the findings of 12-lead electrocardiogram,cardiac enzymes and TTE were summarized;the patients were typed according to the site of origin of coronary artery anomalies,and the causes for the missed diagnosis of TTE were eplored.Chi-square test was used to compare the differences in TTE missed diagnoses.Results Of the 37 patients,31 ones had no or only mild symptoms;most ones had negative results in terms of 12-lead electrocardiography,cardiac enzymes,changes in the size of the cardiac chambers,segmental ventricular wall motion abnormalities and left ventricular systolic function.The patients with anomalous origin of the right coronary artery from left sinus(ARCA-L)gained the largest proportion of 59.45%(22/37);21 patients were diagnosed with anomalous origin of coronary artery arising from the opposite sinus(ACAOS)in the two examinations of TTE,of whom there were 19 cases of ARCA-L,and the detection rate of ACAOS by TTE was 87.5%;all the 13 patients origins in branches and high-grade openings were missed by TTE.The detection rate of ACAOS by TTE was significantly higher than that of coronary artery anomalies originating in branches and in high openings,and the difference was statistically significant(21/24 vs 0/13,P<0.001).Conclusion Most adult AAOCA patients lack specificity in symptoms and related examination results.TTE has a high detection rate of ACAOS,while it is easy to miss the diagnosis of coronary artery anomalies originating from branches and high openings.Ultrasonographers have to identify false negative AAOCA by multi-section and multi-angle scanning and color Doppler flow imaging in order to reduce the rate of missed diagnosis.[Chinese Medical Equipment Journal,2024,45(1):71-75]
6.A study on the job preferences and heterogeneity of medical students from different birthplaces:A discrete choice experiment based on six hospitals in Beijing
Xin-Yan LI ; Yue ZHANG ; Yu-Xin SUN ; Xing LIN ; You-Li HAN
Chinese Journal of Health Policy 2024;17(1):51-59
Objective:To analysis the job preference and heterogeneity of medical students by distinguishing their birthplaces,and to provide reference for optimizing the management of primary health care resources.Methods:Using a cluster sampling method,an online survey of discrete choice experiment was conducted with 925 medical students from six teaching hospitals in Beijing,741 valid questionnaires were obtained,the effective recovery rate was 80.1%.The mixed logit model was used to perform regression analysis on six job attributes and estimate the willingness to pay.Results:There were significant differences in the choice of work location among medical students from different birthplaces.The subgroup results showed that compared to medical students from city,undergraduates from rural and county district preferred a work with sufficient career development opportunities.The results of undergraduate subgroup showed that undergraduates from rural district preferred a work with good environment than those from other birthplaces.Conclusion:There is heterogeneity in job preferences of medical students from different birthplaces.Policy makers should pay attention to the medical students'birthplace,also take the educational level into account to optimize the diversified job attributes,formulating targeted intervention to attract primary health care talents.
7.Analysis of Traditional Chinese Medicine Constitution Types of Nonspecific Low Back Pain and the Influencing Factors for the Thickness of Ligamentum Flavum
Zhou-Hang ZHENG ; Yu ZHANG ; Long CHEN ; Dong-Chun YOU ; Wei-Feng GUO ; Xing-Ming LIU ; Huan CHEN ; Rong-Hai WU
Journal of Guangzhou University of Traditional Chinese Medicine 2024;41(5):1103-1108
Objective To investigate the distribution of the traditional Chinese medicine(TCM)constitution types in the patients with nonspecific low back pain(NLBP)and to explore the correlation of the thickness of ligamentum flavum with the age,body mass index(BMI),gender,the presence of diabetes mellitus,and the grading of hypertension.Methods Sixty patients with NLBP admitted to Guangdong Second Traditional Chinese Medicine Hospital from January 2023 to June 2023 were selected as the study subjects.The TCM constitution types of the patients were identified,the thickness of the ligamentum flavum at lumbar vertebrae 4/5 segment(L4/5)disc level was measured by computerized tomography(CT)scanning,and the patients'age,genders,TCM constitution types,BMI,the presence or absence of diabetes mellitus,and hypertension grading were recorded.Correlation analysis and linear regression analysis were used for the exploration of the relevant influencing factors for the thickness of the ligamentum flavum of patients with NLBP.Results(1)The average thickness of ligamentum flavum in the 60 patients with NLBP was(2.60±0.72)mm.(2)The TCM constitutions of NLBP patients were classified into four types,of which blood stasis constitution was the most common,accounting for 21 cases(35.0%),followed by 19 cases(31.7%)of damp-heat constitution,12 cases(20.0%)of phlegm-damp constitution,and 8 cases(13.3%)of qi deficiency constitution.(3)The results of correlation analysis showed that BMI,gender,TCM constitution type and the presence or absence of diabetes mellitus had no influence on the thickness of ligamentum flavum in NLBP patients(P>0.05),while the age and hypertension grading had an influence on the thickness of ligamentum flavum(P<0.01).(4)The results of linear regression analysis showed that the age had an influence on the thickness of the ligamentum flavum(b = 0.034,t = 6.282,P<0.01),while the influence of the hypertension grading had no influence on the thickness of the ligamentum flavum(P>0.05).Conclusion The TCM constitution type of NLBP patients is predominated by blood stasis constitution,the thickness of ligamentum flavum is significantly affected by the age,and hypertension may be a potential factor affecting the thickness of ligamentum flavum.
8.Analysis of the causes of cage subsidence after oblique lateral lumbar interbody fusion
Zhong-You ZENG ; Ping-Quan CHEN ; Xing ZHAO ; Hong-Fei WU ; Jian-Qiao ZHANG ; Xiang-Qian FANG ; Yong-Xing SONG ; Wei YU ; Fei PEI ; Shun-Wu FAN ; Guo-Hao SONG ; Shi-Yang FAN
China Journal of Orthopaedics and Traumatology 2024;37(1):33-44
Objective To observe the cage subsidence after oblique lateral interbody fusion(OLIF)for lumbar spondylo-sis,summarize the characteristics of the cage subsidence,analyze causes,and propose preventive measures.Methods The data of 144 patients of lumbar spine lesions admitted to our hospital from October 2015 to December 2018 were retrospectively ana-lyzed.There were 43 males and 101 females,and the age ranged from 20 to 81 years old,with an average of(60.90±10.06)years old.Disease types:17 patients of lumbar intervertebral disc degenerative disease,12 patients of giant lumbar disc hernia-tion,5 patients of discogenic low back pain,33 patients of lumbar spinal stenosis,26 patients of lumbar degenerative spondy-lolisthesis,28 patients of lumbar spondylolisthesis with spondylolisthesis,11 patients of adjacent vertebral disease after lumbar internal fixation,7 patients of primary spondylitis in the inflammatory outcome stage,and 5 patients of lumbar degenerative scoliosis.Preoperative dual-energy X-ray bone mineral density examination showed 57 patients of osteopenia or osteoporosis,and 87 patients of normal bone density.The number of fusion segments:124 patients of single-segment,11 patients of two-seg-ment,8 patients of three-segment,four-segment 1 patient.There were 40 patients treated by stand-alone OLIF,and 104 patients by OLIF combined with posterior pedicle screw.Observed the occurrence of fusion cage settlement after operation,conducted monofactor analysis on possible risk factors,and observed the influence of fusion cage settlement on clinical results.Results All operations were successfully completed,the median operation time was 99 min,and the median intraoperative blood loss was 106 ml.Intraoperative endplate injury occurred in 30 patients and vertebral fracture occurred in 5 patients.The mean follow-up was(14.57±7.14)months from 6 to 30 months.During the follow-up,except for the patients of primary lumbar interstitial in-flammation and some patients of lumbar spondylolisthesis with spondylolisthesis,the others all had different degrees of cage subsidence.Cage subsidence classification:119 patients were normal subsidence,and 25 patients were abnormal subsidence(23 patients were grade Ⅰ,and 2 patients were grade Ⅱ).There was no loosening or rupture of the pedicle screw system.The height of the intervertebral space recovered from the preoperative average(9.48±1.84)mm to the postoperative average(12.65±2.03)mm,and the average(10.51±1.81)mm at the last follow-up.There were statistical differences between postop-erative and preoperative,and between the last follow-up and postoperative.The interbody fusion rate was 94.4%.The low back pain VAS decreased from the preoperative average(6.55±2.2 9)to the last follow-up(1.40±0.82),and there was statistically significant different.The leg pain VAS decreased from the preoperative average(4.72±1.49)to the final follow-up(0.60± 0.03),and the difference was statistically significant(t=9.13,P<0.000 1).The ODI index recovered from the preoperative av-erage(38.50±6.98)%to the latest follow-up(11.30±3.27)%,and there was statistically significant different.The complication rate was 31.3%(45/144),and the reoperation rate was 9.72%(14/144).Among them,8 patients were reoperated due to fusion cage subsidence or displacement,accounting for 57.14%(8/14)of reoperation.The fusion cage subsidence in this group had obvious characteristics.The monofactor analysis showed that the number of abnormal subsidence patients in the osteopenia or osteoporosis group,Stand-alone OLIF group,2 or more segments fusion group,and endplate injury group was higher than that in the normal bone mass group,OLIF combined with pedicle screw fixation group,single segment fusion group,and no endplate injury group,and the comparison had statistical differences.Conclusion Cage subsidence is a common phenomenon after 0-LIF surgery.Preoperative osteopenia or osteoporosis,Stand-alone OLIF,2 or more segments of fusion and intraoperative end-plate injury may be important factors for postoperative fusion cage subsidence.Although there is no significant correlation be-tween the degree of cage subsidence and clinical symptoms,there is a risk of cage migration,and prevention needs to be strengthened to reduce serious complications caused by fusion of cage subsidence,including reoperation.
9.Clinical Efficacy of"Triple-posture Positive Bone-setting"Chiropractic Manipulation Combined with Tongluo Huoxue Formula for the Treatment of Lumbar Spinal Stenosis of Qi Deficiency and Blood Stasis Type
Long CHEN ; Zhou-Hang ZHENG ; Yu ZHANG ; Meng-Shu WANG ; Zhao-Yuan ZHANG ; Wei-Feng GUO ; Huan CHEN ; Xing-Ming LIU ; Dong-Chun YOU ; Rong-Hai WU
Journal of Guangzhou University of Traditional Chinese Medicine 2024;41(6):1450-1456
Objective To observe the clinical efficacy of"triple-posture positive bone-setting"chiropractic manipulation combined with Tongluo Huoxue Formula for the treatment of lumbar spinal stenosis(LSS)with qi deficiency and blood stasis syndrome.Methods Sixty patients with LSS of qi deficiency and blood stasis type were randomly divided into trial group and control group,with 30 cases in each group.The trial group was treated with"triple-posture positive bone-setting"chiropractic manipulation(a chiropractic manipulation performed under the positive cooperation of the patients at three postures)combined with Tongluo Huoxue Formula,while the control group was treated with"triple-posture positive bone-setting"chiropractic manipulation combined with conventional western medicine.The course of treatment for the two groups covered 4 weeks.Before and after treatment,the patients of the two groups were observed in the changes of pain visual analogue scale(VAS)score,Japanese Orthopedic Association(JOA)score of lumbar function,Oswestry Disability Index(ODI)score,straight-leg raising test results and serum interleukin 6(IL-6)and C-reactive protein(CRP)levels.After treatment,the clinical efficacy and safety of the two groups were evaluated.Results(1)After 4 weeks of treatment,the total effective rate of the trial group was 96.67%(29/30)and that of the control group was 63.33%(19/30).The intergroup comparison(tested by Fisher's exact test)showed that the clinical efficacy of the trial group was significantly superior to that of the control group(P<0.05).(2)After treatment,the lumbar function indicators of pain VAS scores and ODI scores in the trial group were significantly lower(P<0.05),and the JOA scores were significantly higher than those before treatment(P<0.05),while in the control group,only the ODI scores were significantly lower than those before treatment(P<0.05).The intergroup comparison showed that the decrease of VAS and ODI scores and the increase of JOA scores in the trial group were significantly superior to those in the control group(P<0.05 or P<0.01).(3)After treatment,the Laseque s sign of the trial group was significantly improved compared with that before treatment(P<0.05),while no significant improvement was presented in the control group(P>0.05).The intergroup comparison showed that the improvement of Laseque's sign in the trial group was significantly superior to that in the control group(P<0.01).(4)After treatment,the levels of serum inflammatory factors of IL-6 and CRP in the two groups were lower than those before treatment(P<0.05),and the decrease of serum IL-6 level in the trial group was significantly superior to that in the control group(P<0.05),but CRP level in the two groups after treatment did not differ from that before treatment,no statistically significant difference was shown between the two groups after treatment,either(P>0.05).(5)The incidence of adverse reactions in the trial group was 6.67%(2/30)and that in the control group was 13.33%(4/30),and the intergroup comparison(by Fisher's exact test)showed that there was no significant difference between the two groups(P>0.05).Conclusion The therapeutic effect of"triple-posture positive bone-setting"chiropractic manipulation combined with Tongluo Huoxue Formula exert certain effect for the treatment of LSS patients with qi deficiency and blood stasis syndrome,and it has more obvious advantages in improving the lumbar function,promoting the rehabilitation of the patients,and lowering the level of serum inflammatory factors than"triple-posture positive bone-setting"chiropractic manipulation combined with conventional western medication.
10.Reasons and strategies of reoperation after oblique lateral interbody fusion
Zhong-You ZENG ; Deng-Wei HE ; Wen-Fei NI ; Ping-Quan CHEN ; Wei YU ; Yong-Xing SONG ; Hong-Fei WU ; Shi-Yang FAN ; Guo-Hao SONG ; Hai-Feng WANG ; Fei PEI
China Journal of Orthopaedics and Traumatology 2024;37(8):756-764
Objective To summarize the reasons and management strategies of reoperation after oblique lateral interbody fusion(OLIF),and put forward preventive measures.Methods From October 2015 to December 2019,23 patients who under-went reoperation after OLIF in four spine surgery centers were retrospectively analyzed.There were 9 males and 14 females with an average age of(61.89±8.80)years old ranging from 44 to 81 years old.The index diagnosis was degenerative lumbar intervertebral dics diseases in 3 cases,discogenie low back pain in 1 case,degenerative lumbar spondylolisthesis in 6 cases,lumbar spinal stenosis in 9 cases and degenerative lumbar spinal kyphoscoliosis in 4 cases.Sixteen patients were primarily treated with Stand-alone OLIF procedures and 7 cases were primarily treated with OLIF combined with posterior pedicle screw fixation.There were 17 cases of single fusion segment,2 of 2 fusion segments,4 of 3 fusion segments.All the cases underwent reoperation within 3 months after the initial surgery.The strategies of reoperation included supplementary posterior pedicle screw instrumentation in 16 cases;posterior laminectomy,cage adjustment and neurolysis in 2 cases,arthroplasty and neuroly-sis under endoscope in 1 case,posterior laminectomy and neurolysis in 1 case,pedicle screw adjustment in 1 case,exploration and decompression under percutaneous endoscopic in 1 case,interbody fusion cage and pedicle screw revision in 1 case.Visu-al analogue scale(VAS)and Oswestry disability index(ODI)index were used to evaluate and compare the recovery of low back pain and lumbar function before reoperation and at the last follow-up.During the follow-up process,the phenomenon of fusion cage settlement or re-displacement,as well as the condition of intervertebral fusion,were observed.The changes in in-tervertebral space height before the first operation,after the first operation,before the second operation,3 to 5 days after the second operation,6 months after the second operation,and at the latest follow-up were measured and compared.Results There was no skin necrosis and infection.All patients were followed up from 12 to 48 months with an average of(28.1±7.3)months.Nerve root injury symptoms were relieved within 3 to 6 months.No cage transverse shifting and no dislodgement,loosening or breakage of the instrumentation was observed in any patient during the follow-up period.Though the intervertebral disc height was obviously increased at the first postoperative,there was a rapid loss in the early stage,and still partially lost after reopera-tion.The VAS for back pain recovered from(6.20±1.69)points preoperatively to(1.60±0.71)points postoperatively(P<0.05).The ODI recovered from(40.60±7.01)%preoperatively to(9.14±2.66)%postoperatively(P<0.05).Conclusion There is a risk of reoperation due to failure after OLIF surgery.The reasons for reoperation include preoperative bone loss or osteoporosis the initial surgery was performed by Stand-alone,intraoperative endplate injury,significant subsidence of the fusion cage after surgery,postoperative fusion cage displacement,nerve damage,etc.As long as it is discovered in a timely manner and handled properly,further surgery after OLIF surgery can achieve better clinical results,but prevention still needs to be strengthened.

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