Objectives:To analyze the correlation between cervical spine postures and different types of odontoid fractures when injured in different directions of violence using finite element method.Methods:Based on the experience of establishing the finite element model of the upper cervical vertebrae in the early stage,and verified as effective through literature published abroad and in vitro experiments,different positions of the cervical spine(neutral position,flexion position,extension position,lateral bending position,and rotation position)were preset on the established three-dimensional nonlinear finite element model of the normal occip-ital-atlantoaxial complex,and an acceleration of 8m/s2 was applied in each direction of violence[anterior,pos-terior,lateral,top(vertical downward)].The von Mises stress values in different regions of different types(An-derson and D'Alonzo type)of odontoid process fractures were calculated,and stress contour maps were ex-tracted.Results:When subjected to anterior violence,the maximum von Mises stress values were generated in an extension position,with stress concentration in the vertebral body of the axis(Type Ⅲ)(0.41MPa).When subjected to posterior violence,the maximum von Mises stress values were generated when the cervical vertebrae were in a flexion position,with stress concentration in the odontoid process base(Type Ⅱ)(0.52MPa)and the vertebral body of the axis(Type Ⅲ)(0.55MPa).When subjected to lateral violence,the maximum von Mises stress values were generated when the cervical vertebrae were in a flexion position,with stress concen-tration in the odontoid process base(Type Ⅱ)(0.51MPa)and the vertebral body of the axis(Type Ⅲ)(0.43MPa).When subjected to vertical downward violence,the stress values in each body position increased significantly,the stress at the tip of the odontoid process(Type Ⅰ)in the flexion position reached 0.99MPa,the stress at the base of the odontoid process(Type Ⅱ)in the lateral flexion position reached 1.16MPa,and the stress at the axis vertebral body(Type Ⅲ)in the rotational position was 0.85MPa.Conclusions:When the upper cervi-cal spine is in a flexion position and receives a vertically downward force,it is prone to odontoid process tip fractures(Type Ⅰ);When the upper cervical spine is in a flexion position and receives a posterior or lateral force,or when it is in a lateral bending position and receives a vertically downward force,it is prone to odontoid process base fractures(Type Ⅱ);When the upper cervical spine is in a flexion position and receives a posterior force,or when it is in a rotational position and receives a vertically downward force,it is prone to axis vertebral body fractures(Type Ⅲ).

Objectives:To investigate the clinical efficacies of endoscopic cross-overtop decompression(Cross-overtop)and endoscopic unilateral laminotomy bilateral decompression(Endo-ULBD)in the treatment of severe lumbar spinal stenosis.Methods:A retrospective study was conducted on the patients with single-level severe lumbar spinal stenosis admitted and treated with Cross-overtop decompression(30 cases)and En-do-ULBD(30 cases)in our hospital between July 2021 and December 2022.There were 37 male cases and 23 female cases.The average age of the Cross-overtop group was 66.2±8.8 years,and the average age of the Endo-ULBD group was 71.4±8.7 years.The patients were followed up at 1 week,3 months,6 months,and≥ 12 months(final)after operation.Clinical outcomes were assessed using the visual analog scale(VAS)score,Oswestry disability index(ODI),and Japanese Orthopaedic Association(JOA)scores.The sagittal diameter of the affected spinal canal was measured to evaluate central canal expansion.Postoperative excellent and good rate of efficacy were determined using the MacNab criteria at 12 months'or the final follow-up.Results:All 60 patients completed follow-up with a duration ranging from 12 to 25 months.Both groups showed significant improvements in VAS scores for low back and leg pain and ODI at each follow-up interval compared to the previous assessment.The Cross-overtop group demonstrated a greater expansion rate(5.08％)of the sagittal di-ameter of the central canal at the affected level compared to the Endo-ULBD group(1.59％),with statistically significant differences(P＜0.05).At postoperative 12-month or final follow-up,MacNab evaluation revealed an excellent and good rate of 90.0％in the Cross-overtop group and 83％in the Endo-ULBD group.Conclusions:Cross-overtop decompression is one of the minimally invasive endoscopic surgical techniques for treating severe lumbar spinal stenosis,which is safe and effective with distinct advantages.

Objectives:To investigate the mechanism of insulin-like growth factor 1(IGF-1)in mediating intervertebral disc cell aging through regulating the activity of the silent information regulator sirtuin 1(SIRT1).Methods:The intervertebral disc tissues of eight-week old female Spargue Dawley(SD)rats were dissected,from which annulus fibrosus(AF)cells were isolated and cultured in vitro.The effects of IGF-1 on the aging of AF cells were studied by β-galactosidase(SA-β-Gal)staining,cell proliferation assays,and cell migration experiments,in exposure to different concentrations of recombinant rat IGF-1(0,1,10,50,100ng/mL)in culture.The molecular mechanism of IGF-1 on AF cells was further explored by Western blot analysis.Results:After treatment with exogenous IGF-1 at different concentrations,SA-β-Gal staining and western blot results showed that IGF-1 promoted AF cell aging in a concentration-dependent manner.The CCK-8 analysis showed that low concentrations of IGF-1 significantly induced AF cell proliferation.Transwell assay results showed that low concentrations of IGF-1 profoundly enhanced the migratory capability of AF cells,whereas IGF-1 at high concentrations demonstrated no significant effect on AF cell migration.Western blot results showed that IGF-1 could downregulate the expression of SIRT1 and elevate the acetylation of p53.Conclusions:IGF-1 can promote AF cell aging though inhibiting SIRT1 expression and activity.

Objectives:To analyze the mechanical properties of the personalized artificial vertebral body of 3D-printed poly etheretherketone(PEEK)matrix composites after implantation and its effect on adjacent tissues using finite element analysis.Methods:The CT scan data of a healthy male volunteer was extracted for 3D reconstruction,the finite element model of the lumbar spine(L1-L5)was constructed,and the ranges of motion of different lumbar vertebrae segments in various motion states were simulated,after that,the effectiveness of the finite element model was verified by comparing with the research data in previous studies.The total en bloc spondylectomy(TES)was simulated to remove the L3 vertebral body and adjacent intervertebral discs,and a personalized artificial vertebral body was designed based on the design principles of artificial vertebral body and was fixed to the adjacent lumbar segments using a posterior approach with a titanium alloy rod-screw system.The interior of the artificial vertebral body was designed as honeycomb structures with densities of 30％,50％,and 70％.PEEK/hydroxylaptite(HA)composite materials were selected as the external shell of the personalized lumbar artificial vertebral body,and PEEK/carbon fiber(CF)materials were used as the internal filler.The forces and moments of each vertebral body in the upright,forward bending,backward extension,lateral bending and rotation states were obtained through the Vicon Nexus system,and as the boundary con-ditions of finite element analysis,the appropriate size of the bone graft hole and the thickness of the shell were selected,and then the inside of the artificial vertebral body was filled with hexagonal honeycombs of different densities.The models of young and middle-aged and elderly groups were established by changing the elastic modulus of cortical bone and cancellous bone,and the finite element simulation was carried out on the models.The maximum stress values of the artificial vertebral body,fixation system and adjacent upper and lower endplates under different motion states,and the stress occlusion rate of the artificial vertebral body were analyzed to evaluate the performance of the artificial vertebral body.Results:The maximum stress value of artificial vertebral body(42.25MPa)was lower than the yield strength of PEEK/HA(65MPa),and the maximum stress value of internal honeycomb(26.38MPa)was lower than the yield strength of PEEK/CF(90MPa);The maximum stress value of rod-screw system(271.75MPa)was lower than the yield strength of titanium alloy(900MPa),and the maximum stress value of the endplate on adjacent endplate(7.87MPa)was lower than the yield strength of cartilage endplate(50MPa).The stress occlusion rate of artificial vertebral body with 30％honeycomb density in the middle-aged and elderly group was the lowest.Conclusions:The 3D-printed personalized artificial vertebral body of PEEK matrix composite can complete the structure reconstruction of lumbar spine well after TES with good biomechanical stability.

Objectives:To investigate the efficacy and safety of staged three-column osteotomy(S-3CO)with posterior column connection preserved in the corrective surgery for scoliosis.Methods:The clinical data of 18 patients(7 males and 11 females,11.8±7.7 years old,followed up for 37.5±12.4 months)with scoliosis treated with S-3CO in our hospital from January 2015 to December 2022 were retrospectively analyzed(S-3CO group).The Cobb angle of the main curve,the horizontal distance between C7 and central sacral vertical line(C7-CSVL)and the sagittal vertical axis(SVA),regional Cobb angle(RCA),regional kyphosis angle(RKA)of the patients in the S-3CO group were collected and compared before operation and at the final follow-up.The complications were analyzed.15 patients with scoliosis who received the traditional three-column osteotomy(3CO)technique during the same period were analyzed(3CO group).There were no statistical difference between the two groups in age,gender,osteotomy grade,and number of fixed segments(P＞0.05).The operative time and the blood loss volume were compared between the two groups.Results:The preoperative Cobb angle of the main curve was 66.7°±23.9°,RCA was 35.3°±6.7°,and RKA was 25.2°±14.2° of the patients in the S-3CO group.The final follow-up Cobb angle of the main curve was 25.7°±13.3°,RCA was 17.6°±6.3°,and RKA was 12.6°±10.6°.The differences in the values between the final follow-up and preoperation were significantly different(P＜0.05).The preoperative C7-CSVL and SVA were 27.9±14.5mm and 29.0±8.7mm,respectively,and 12.7±5.5mm and 17.4±5.6mm respectively at the final follow-up,with statistical differences(P＜0.05).A total of 3 patients in S-3CO group had neuromonitoring alarms during the operation,and 1 of whom had postoperative neurological complication,which was recovered from grade 2 to grade 4 in muscle strength of the right lower limb at 2 years follow-up after conservative treatment.The operative time of S-3CO group was significantly shorter than that of the 3CO group(358.3±140.2min vs 416.3±121.2min,P＜0.05),and the blood loss volume was significantly less than that of the 3CO group(850.0±359.3mL vs 977.3±236.4mL,P＜0.05).Conclusions:By preserving part of the posterior column connection,S-3CO can achieve sufficient local correction and improve the overall corrective efficiency of scoliosis.Preserving the connection and protection of the posterior structure during osteotomy reduces the risk of neurologic injury.

Objectives:To retrospectively review the clinical data from multiple centers of patients diagnosed with spinal tuberculosis,and identify key indicators that reflect the disease's characteristics and clinical man-agement to propose a novel classification system for spinal tuberculosis;To summarize the surgical treatment methods and outcomes of patients with complete data who were followed up for more than 1 year for surgical efficacy evaluation.Methods:The clinical data of 358 spinal tuberculosis patients diagnosed and treated at multiple centers between January 2007 and December 2022 were collected and analyzed.The patients aged 35.5±28.9 years old,and were consisted of 189 males and 169 females.There were 346 cases of active spinal tuberculosis and 12 cases of inactive tuberculosis.The distribution of lesion sites included cervical spine in 37 cases,cervicothoracic spine in 24 cases,thoracic spine in 126 cases,thoracolumbar spine in 79 cases,lumbar spine in 63 cases,and lumbosacral spine in 29 cases.The number of affected vertebrae per lesion was 3.1±1.9(ranged from 1 to 12).Clinical manifestations included pain,limited mobility,fever,elevated erythrocyte sedimentation rate,destruction and absorption of vertebrae and intervertebral discs,cold abscesses,and sequestra.Among the patients,256 patients exhibited concomitant kyphotic deformities,and 66 patients presented with varying degrees of spinal cord or nerve dysfunction.Using expert panel discussions and opin-ion surveys,indicators that reflect the characteristics of spinal tuberculosis were identified and subjected to correlation analysis with the degrees of kyphosis.Based on these findings,a new comprehensive classification system(ASM classification)grounded in key indicators was designed and then re-evaluated and tested for reli-ability.In parallel,the clinical data of 117 patients with over one year of postoperative follow-up and com-plete records were collected,and the surgical efficacy was assessed according to visual analogue scale(VAS)score for pain,examination of spinal cord or nerve function,and measurement of Cobb angle of kyphosis as well as evaluation of graft fusion conditions on X-ray and CT.Results:The expert discussions confirmed that pathological stage,lesion location,number of affected vertebrae,and the presence of kyphotic deformity and spinal cord or nerve dysfunction were key indicators in the diagnosis and treatment of spinal tuberculosis;Other indicators such as the extent of vertebral destruction,segmental instability,and the number and size of sequestra and cold abscesses were found to be less specific.Correlation analysis demonstrated a significant association between kyphotic deformity and factors such as disease duration,lesion location,affected segment,and spinal cord or nerve involvement(P＜0.05).Based on the validation results,a new comprehensive classifica-tion system was proposed.The spinal tuberculosis was categorized into two main types based on lesion activi-ty,the active spinal tuberculosis(type Ⅰ)and inactive spinal tuberculosis(type Ⅱ).Type Ⅰ was further divid-ed into four subtypes:type A-early-stage spinal tuberculosis,type B-progressive spinal tuberculosis,type C-special type including skip lesions,and type D-spinal appendage tuberculosis;Type Ⅱ was divided into two subtypes:type A-deformity-stable type,type B-deformity-progressive type.Additionally,the four key indicators-lesion location,number of affected vertebrae,presence and degree of kyphotic deformity,and spinal cord or nerve impairment were included as auxiliary indicators.Reliability analysis showed that the new classification system had good consistency and reproducibility.Among the 117 patients with over one year of postoperative follow-up and complete records,12 with cervical tuberculosis underwent anterior ap-proach surgery,104 patients with lesions below the cervicothoracic junction underwent posterior-only surgery,and 1 thoracolumbar case underwent additional debridement of a cold abscess via a small contralateral ab-dominal incision during posterior surgery.Follow-up results revealed:VAS score was 1.9±0.3(1-3),kyphotic Cobb angle was 15.61°±8.44°(4°-40°);The patients with abnormal spinal cord nerve function were fully recov-ered to normal at the final follow-up,and the above-mentioned indicators were improved with statistically significant differences comparing with the preoperative values(P＜0.05);111 patients were clinically cured and bony fused on CT images;6 patients experienced tuberculosis recurrence,among which,5 failed in internal fixation due to graft non-fusion and underwent re-operation.Conclusions:The new classification system(ASM)effectively captures the clinical characteristics of spinal tuberculosis and facilitates diagnosis,treatment plan-ning,and clinical communication.For patients with spinal tuberculosis below the cervicothoracic junction,a purely posterior surgical approach also represents an advantageous treatment option.

Objectives:To investigate the clinical efficacy of occipitocervical fusion with the occipital screw-rod-multiaxial screw internal fixation system in treating"sandwich"deformity with atlantoaxial disloca tion.Methods:A retrospective analysis was conducted on 62 patients who underwent posterior reduction,bone graft fusion,and occipitocervical internal fixation for"sandwich"deformity with atlantoaxial dislocation from January 2017 to January 2023.There were 19 males and 43 females,aged 51.1±23.5 years(29-72 years).The patients were divided into two groups based on the different fixation methods of the occipital screws used in the two types of occipitocervical internal fixation systems:group A of 38 patients utilized the occipital screw-rod-multiaxial screw system,consisting of 12 males and 26 females,aged 50.9±24.8 years(29-72 years),and the imaging findings revealed brainstem or cervical spinal cord compression in 30 cases,syringomyelia in 6 cases,and Chiari malformation in 2 cases;And group B of 24 cases utilized the occipital plate-rod-multiaxial screw system,consisting of 7 males and 17 females,aged 51.4±22.4 years(32-69 years),and the imaging findings revealed brainstem or cervical spinal cord compression in 16 cases,syringomyelia in 6 cases,and Chiari malformation in 2 cases.Group A was followed up for 36.5±11.8 months and Group B was followed up for 36.1±9.8 months.No statistically significant differences were observed between the two groups in terms of age,sex,imaging findings,or surgery style(P＞0.05).A comparison was performed between the groups regarding intraoperative blood loss,operative time,follow-up period,and complication rates.Clini-cal outcomes were evaluated preoperatively and at the final follow-up using the neck pain visual analog scale(VAS)score,neck disability index(NDI),and Japanese Orthopaedic Association(JOA)score.The cross-sectional and sagittal bone fusion area of the graft site,atlantodental interval(ADI),space available for cord(SAC),clivus canal angle(CCA),and cervico-medullary angle(CMA)were measured preoperatively,1 week postoperatively,and at the final follow-up in both groups.Results:Group A and group B weren't significantly different in intraoperative blood loss(362.4±89.1mL vs 345.1±93.8mL,P＞0.05)and operative time(144.8±35.6min vs 143.7±36.2min,P＞0.05).In group B,rod fractures occurred in 2 cases and loss of reduction was observed in 3 cases,whereas the remaining patients maintained stable screw-rod fixation.Neither group experienced severe complications such as spinal cord injury or cerebrospinal fluid leakage.Both groups demonstrated statistically significant differences between preoperative NDI,VAS,JOA scores and those measured at the final follow-up(P＜0.05),while no statistically significant differences existed between the two groups at the same time points(P＞0.05).Statistically significant differences were observed between preoperative and postoperative(1-week and final follow-up)measurements for ADI,SAC,CCA and CMA in both groups(P＜0.05),while no significant in-tergroup differences were found at corresponding time points(P＞0.05).In group A,the cross-sectional area and the sagittal area of the graft site were 385.44±84.51mm2 and 290.28±1 10.41mm2 in postoperative 1 week,and 267.06±66.13mm2 and 204.54±83.85mm2 at the final follow-up;which in group B were 442.61±76.85mm2 and 267.21±104.63mm2 in postoperative 1 week,and 172.43±37.37mm2 and 124.87±48.10mm2 at final follow-up.Comparisons between groups revealed no statistically significant differences in either cross-sectional or sagittal graft areas at 1 week postoperatively(P＞0.05),however,significant differences were observed at the final fol-low-up(P＜0.05)for both parameters between the two groups.Conclusions:The occipital screw-rod-multiaxial screw internal fixation system presents comparable restoration effects to the occipital plate-rod-multiaxial screw system in treating"sandwich"deformity with atlantoaxial dislocation.It exhibits satisfactory implant fusion postoperatively and achieves reliable occipitocervical fixation.

Objectives:To investigate the short-term effect of soft endoscope-assisted single-segment cervical artificial disc replacement(ADR)in the treatment of cervical spondylosis.Methods:A retrospective analysis was conducted on the clinical data of 24 cases of cervical spondylosis treated with soft endoscope-assisted single-segment ADR in our hospital from June 2023 to May 2024,of which,8 cases were male and 16 cas-es were female,aged 25 to 68 years old(47.0±11.9 years old).There were 7 cases of cervical spondylotic radiculopathy,14 cases of cervical spondylotic myelopathy,and 3 cases of mixed cervical spondylosis.All of the patients were with single-segment lesions,including 2 cases of C3/4,6 cases of C4/5,12 cases of C5/6,and 4 cases of C6/7.The length of surgical incision,intraoperative bleeding,operative time,postoperative drainage,hospitalization time and complications were recorded;Prevertebral soft tissue edema was evaluated;Japanese Orthopaedic Association(JOA)score was assessed for cervical spine motor function,and visual analog scale(VAS)score was evaluated for neck and shoulder pain on 1d before surgery,at 1 week after surgery,1 month and 3 months after surgery.Results:Surgery was successfully completed in all patients,and no com-plications such as spinal cord/nerve root injury or cerebrospinal fluid leakage were detected during the opera-tion.Operative time was 34-123min(66.6±20.8min),length of surgical incision was 2.5-3cm(2.6±0.2cm),intra-operative bleeding volume was 5-50mL(19.6±12.6mL),postoperative drainage volume was 0-60mL(13.5±18.8mL),and postoperative hospitalization time was 3-8d(5.1±1.6d).No postoperative complications such as cervical subcutaneous hematoma and dysphagia were observed.Postoperative imaging revealed no significant prevertebral soft tissue edema.The postoperative VAS and JOA scores were significantly improved at all time points compared with the preoperative values(P＜0.05).The overall efficacy was assessed according to the im-provement rate of JOA score at 3 months after surgery:12 cases were excellent,12 cases were good,and the rate of excellent and good was 100％(24/24).Conclusions:Soft endoscope-assisted single-segment ADR for the treatment of cervical spondylosis is small in trauma and short in operative time,which has certain clinical application prospects.

Objectives:To analyze the causes and clinical characteristics of re-operative surgery of patients with high lumbar intervertebral space height(hIVSH),and to clarify the effect of hIVSH restoration on clinical results and lumbar-pelvic alignment.Methods:Clinical data from 42 patients who underwent re-operative surgery with high intervertebral cages(≥ 14mm)placement in our hospital from January 2014 to November 2024 were collected.The patients included 23 males and 19 females,aged 41-85 years old(59.5±8.6 years old).23 patients undergone re-operation at the original segment were included in the original segment re-operation group(group A);19 patients who were re-operated due to adjacent segment degeneration(ASD)were included in the adjacent segment re-operation group(group B).The time interval between re-operation and the previous surgery,preoperative and final follow-up visual analogue scale(VAS)score and Japanese Orthopaedic Association(JOA)score were collected and analyzed.In group B,the intervertebral space height(IVSH),fusion area of the previous fusion segment,range of motion of the previous surgical segment,Pfirrmann grades of the intervertebral disc at the re-operative segment,pelvic inclination(PI),pelvic tilt(PT),and lumbar lordosis(LL)were measured.Group B was further divided into the hIVSH group(group B1,full restoration of IVSH)and the low IVSH group(group B2,incomplete restoration of IVSH)based on whether the IVSH was fully restored in the previous fusion segment.The above parameters were thereby compared.Results:The re-operations were all completed successfully in 42 cases.Herein,36 cases(85.7％)were the second surgeries,5 cases(11.9％)were the third surgeries,and 1 case(2.4％)was the fourth surgery.A total of 54 lower lumbar segments were re-operated,including 17 at L3/4(31.5％),30 at L4/5(55.6％),and 7 at L5/S1(12.9％).The time interval between surgeries in group B1 was 9.55±3.47 years,which was longer than that in group B2(4.55±3.62 years)and group A(3.29±5.36 years).The follow-up period was 0.25-11 years(6.24±2.96 years).At the final follow-up,VAS and JOA scores were significantly improved in groups A,B1,and B2 compared with preoperative scores(P＜0.05);Group B2 was higher in VAS score(P＜0.05)and lower in JOA score(P＜0.01)than group A before operation,and was lower in JOA score than group A at final follow-up(P＜0.05).B1 group was lower in JOA score than group A before operation(P＜0.02).There was no significant difference in fusion area in previous operated segment between groups B1 and B2(1.26±0.30cm2 vs 1.13±0.15cm2,P＞0.05)or range of motion(5.22°±1.97° vs 3.93°±1.79°,P＞0.05).However,the Pfirrmann grades of intervertebral disc degeneration was better in group B1 than group B2.There was no significant difference in PI,PT,or LL between groups B1 and B2 preoperatively and postoperatively(P＞0.05).Nonetheless,preoperative LL in group B1(46.57°±5.61°)was significantly greater than group B2(40.08°±6.5°)(P＜0.05).Conclusions:Complete restoration of hIVSH does not significantly affect interbody fusion or segmental stability.However,it helps to improve LL which results in better Pfirrmann grade of adjacent segment.

Objectives:To investigate the clinical outcomes of unilateral biportal endoscopy assisted unilateral laminotomy for bilateral decompression(ULBD)in the treatment of lumbar spinal stenosis under local anesthe-sia,and to compare the anesthetic effects of single-stage and two-stage local anesthesia.Methods:A retro-spective analysis was conducted on the data of 106 patients with lumbar spinal stenosis who underwent uni-lateral biportal endoscopy assisted ULBD treatment under local anesthesia in our hospital from January 2022 to June 2023.There were 51 males and 55 females,aged 55-83(66.7±14.5)years old,with the following le-sion segments:17 cases at L3-4,36 cases at L4-5,and 53 cases at L5-S1.Schizas classification:25 cases of grade B,36 cases of grade C,and 45 cases of grade D.Among them,52 patients underwent single-stage local anesthesia and were included in the single anesthesia group(Group A),while 54 patients received two-stage local anesthesia and were included in the two-stage local anesthesia group(Group B).There were no statistically significant differences in age,gender ratio,body mass index(BMI),surgical segments,Schizas classification and American Society of Anesthesiologists(ASA)classification between the two groups of patients.The perioperative complications,operative time,as well as the visual analogue scale(VAS)score,oxygen saturation,mean arterial pressure,heart rate in both groups before surgery(T1),during exposure(T2),during traction of the nerve root(T3),and immediately after surgery(T4)were recorded;The VAS scores for low back pain and leg pain,as well as the Oswestry disability index(ODI),were compared between the two groups before and after surgery.The MacNab assessment criteria were used to evaluate the overall postoperative efficacy of the patients at the final follow-up.Results:All patients successfully completed the operation.Two cases had dural tear,but no dural repair was performed;Five cases had mild headache,which disappeared after symptomatic treatment;Four cases had increased lower limb pain and numbness compared to pre-operative conditions,which were treated with symptomatic treatment for swelling reduction,and the symptoms alleviated or disappeared 3-5d after surgery;All incisions healed in stage Ⅰ.During the operation,the vital signs remained stable throughout and no unexpected incidents occurred.There was no statistical difference between group A and group B in operative time(101.9±17.3min vs.103.6±15.9min,P＞0.05).No statistically significant difference was observed in VAS scores,mean arterial pressure and heart rate between the two groups at T1 and T2(P＞0.05).At T3 and T4,the VAS scores,mean arterial pressure and heart rate of group A were significantly higher than those of group B(P＜0.05).At each time point after surgery,the VAS scores and ODI of the two groups improved significantly compared with those before surgery(P＜0.05),but there was no statistically significant difference between the two groups at the same time point(P＞0.05).At the final follow-up,31 cases in group A were excellent,14 cases were good,and 7 cases were fair,with an excellent and good rate of 86.5％;36 cases in group B were excellent,13 cases were good,and 5 cases were fair,with an excellent and good rate of 90.7％.There was no statistically significant difference in the excellent and good rate between the two groups(P＞0.05).Conclusions:The unilateral biportal endoscopy technique under local anesthesia for ULBD in the treatment of lumbar spinal canal stenosis can achieve good clinical efficacy,and two-stage local anesthesia provides a superior analgesic effect compared to single-stage local anesthesia.This method holds significant clinical application value,particularly for patients with lumbar spinal canal stenosis accompanied by complex comorbidities and at high risk for general anesthesia.