BACKGROUND:Upper lumbar spinal stenosis is a multifactorial degenerative disorder of the spine.For narrowing of the spinal canal in the upper lumbar region(L1-L4),surgical decision-making is particularly complex.Existing minimally invasive surgeries each have their own advantages and limitations.Currently,there are few reports on biomechanical comparison and finite element analysis of different surgical methods for the treatment of high lumbar spinal stenosis.OBJECTIVE:To analyze the biomechanical impact of endoscopic unilateral laminotomy for bilateral decompression,transforaminal endoscopic lumbar decompression,and cross-overtop decompression in the treatment of upper lumbar spinal stenosis using endoscopy,and to verify the reliability and effectiveness of these three surgical techniques in treating upper lumbar spinal stenosis,providing a biomechanical basis for clinical decision-making.METHODS:The CT images of the lumbar spine of a healthy volunteer were selected,and the finite element model M0 of the normal lumbar L1-L5 segments was established using Mimics,Geomagic,Solid works,and Ansys software.The L2-L3 segment,representing upper lumbar characteristics,was chosen.Based on this model,the surgical models for endoscopic unilateral laminotomy for bilateral decompression(M1),transforaminal endoscopic lumbar decompression(M2),and cross-overtop decompression(M3)were established.Using software,the changes in the range of motion of the entire lumbar segment and the maximum Von Mises stress of the intervertebral discs were simulated and evaluated for each group of models under six loading conditions:flexion,extension,left lateral bending,right lateral bending,left rotation,and right rotation.RESULTS AND CONCLUSION:(1)Compared with model MO,the range of motion in M1,M2,and M3 increased under all six conditions,with M1 showing a greater increase.(2)M1 and M2 demonstrated significant increases in range of motion under forward bending,extension,and right rotation,while the increase under other conditions remained below 7％.(3)Compared with model M3,model M1 exhibited slightly increased overall joint range of motion during extension and left bending,while no significant changes were observed in other aspects,and the L1-L5 lumbar segments did not reach an unstable state.(4)In model M1,the maximum Von Mises stress of the intervertebral discs increased most significantly under flexion and extension loading conditions.However,under left lateral bending,right lateral bending,left rotation,and right rotation loading conditions,the increase did not exceed 5％.(5)These findings suggest that due to the sagittal anatomical characteristics of the facet joints,the unilateral laminotomy for bilateral decompression technique,while decompressing,involves resection of more facet joints,which impacts overall segmental stability.The transforaminal endoscopic lumbar decompression technique is suitable for patients with foraminal stenosis but cannot achieve complete decompression for those with severe ventral central stenosis.The Cross-Overtop technique effectively enlarges the volume of the central canal and lateral recess,optimizing decompression,and shows unique advantages in treating upper lumbar spinal stenosis.

BACKGROUND:With changing lifestyles and aging,sagittal spinal imbalance has become a common orthopedic issue significantly affecting knee and pelvic function.Understanding the impact of sagittal spinal imbalance and its compensatory mechanisms is crucial for improving the clinical management of chronic pain.OBJECTIVE:To evaluate the alignment of the spine-pelvis-lower extremities using whole-body EOS imaging,analyze the correlation between spinal sagittal imbalance and knee joint parameters,and explore their compensatory mechanisms.METHODS:A total of 71 patients with chronic low back pain or patellofemoral pain who visited Department of Orthopedics,First Affiliated Hospital of Soochow University between January 1,2021 and December 31,2023 were included.Radiographic measurements were performed using whole-body EOS to determine pelvic tilt,pelvic incidence,lumbar lordosis,sagittal vertical axis,global tilt,hip-knee-angle,knee flexion angle,lateral distal femoral angle,and medial proximal tibial angle.Patients were classified into normal group(pelvic incidence-lumbar lordosis＜10°),compensated group(10°＜pelvic incidence-lumbar lordosis＜20°),and decompensated group(pelvic incidence-lumbar lordosis＞20°)based on the SRS-Schwab spinal deformity classification according to pelvic incidence-lumbar lordosis difference.The differences in radiographic parameters among the groups were analyzed.The differences in American Knee Society Knee Score and Oswestry Disability Index scores were compared among each group.Patients were divided into chronic low back pain group and non-chronic low back pain group,patellofemoral pain group and non-patellofemoral pain group based on clinical symptoms,and the relationship between radiographic parameter differences and clinical symptoms was analyzed.RESULTS AND CONCLUSION:(1)When pelvic incidence-lumbar lordosis was less than 20°,lateral distal femoral angle and medial proximal tibial angle tended to stabilize.When pelvic incidence-lumbar lordosis was greater than 20°,it showed a linear correlation with lateral distal femoral angle and medial proximal tibial angle,with lateral distal femoral angle increasing and medial proximal tibial angle decreasing with increasing pelvic incidence-lumbar lordosis values.(2)Compared with the normal group,the compensated group had significantly increased pelvic tilt(P＜0.01),while knee joint parameters hip-knee-angle and knee flexion angle showed no significant differences;the decompensated group showed significant increases in pelvic tilt(P＜0.01),and decreases in hip-knee-angle,and knee flexion angle(P＜0.01).Compared with the compensated group,the decompensated group showed a significant decrease in hip-knee-angle(P＜0.05),but had no significant differences in pelvic tilt and knee flexion angle.(3)Compared with the non-patellofemoral pain group,patients with patellofemoral pain had significant decreases in spinal lumbar lordosis,lateral distal femoral angle,and medial proximal tibial angle(P＜0.05)and a significant increase in pelvic incidence-lumbar lordosis(P＜0.05).(4)Patients with low back pain had significant differences in radiographic parameters compared with the non-chronic low back pain group(P＜0.05).(5)Compared with the normal group,both the compensated and decompensated groups showed a significant decrease in American Knee Society Knee Score scores and a significant increase in Oswestry Disability Index scores(P＜0.05).Compared with the compensated group,the decompensated group showed a significant decrease in American Knee Society Knee Score scores and a significant increase in Oswestry Disability Index scores(P＜0.05).(6)Pelvic incidence-lumbar lordosis values increased with age and were higher in females compared with males.(7)This study systematically reveals the spine and lower limbs play an important role in disease progression and clinical symptoms.Associated symptoms low back pain and patellofemoral pain are related to the stability of the spine-pelvis-lower extremity alignment.Furthermore,spinal sagittal imbalance is more severe in elderly and female patients.

BACKGROUND:With the development of the aging trend of society,the incidence of femoral neck fractures is increasing.Currently,the preferred surgical treatment is cannulated screw internal fixation.However,post-surgical femoral neck shortening occurs in some cases,resulting in impaired hip functionality.OBJECTIVE:To investigate the incidence of femoral neck shortening following the use of half-threaded cannulated screws for internal fixation in patients with femoral neck fractures,to analyze the effect on hip function,and to identify factors contributing to neck shortening.METHODS:A retrospective analysis was conducted on the medical records of 102 patients treated with half-threaded cannulated screws in an inverted triangle setup for femoral neck fractures at Affiliated Hai'an Hospital of Nantong University from January 2016 to January 2021.This group included 36 males and 66 females at the mean age of(57.2±7.7)years,with 34 cases of Garden type Ⅰ and Ⅱ fractures and 68 of Garden type Ⅲ and Ⅳ fractures.The mean bone mineral density value T was-2.8 SD.The Harris score was used to evaluate the hip function.During the follow-up period,the occurrence of femoral neck shortening was determined using X-ray imagery,and the factors influencing this shortening were examined using both univariate and multivariate regression analyses.RESULTS AND CONCLUSION:(1)Among the 102 patients with femoral neck fractures,30 patients developed femoral neck shortening,accounting for 29.4％.72 patients had no femoral neck shortening(70.6％).(2)The Harris score for patients experiencing neck shortening was significantly lower than that for patients without shortening(P＜0.05).(3)The study identified several factors associated with femoral neck shortening following the internal fixation of femoral neck fractures included age,gender,bone mineral density value T,preoperative Garden classification,and quality of reduction.These factors not only affect the shortening of the femoral neck after surgery,but are also directly related to the functional performance of the patient's hip joint.(4)Femoral neck shortening after surgery for femoral neck fracture is associated with various clinical parameters,especially the patient's age,gender,bone mineral density,preoperative classification,and accuracy of reduction during surgery.

BACKGROUND:The most common complication of traumatic femoral neck fractures after internal fixation is femoral head necrosis.Currently,many studies have reported on the risk factors that affect the occurrence and development of postoperative femoral head necrosis,but there is still a lack of tools to predict the risk of femoral head necrosis after internal fixation of femoral neck fractures.OBJECTIVE:To develop a predictive model that estimates the risk of femoral head necrosis shortly after patients with femoral neck fractures receive cannulated screw internal fixation.METHODS:A retrospective analysis reviewed clinical records of 172 patients who underwent cannulated screw internal fixation for femoral neck fractures at Department of Orthopedics of Mianyang Central Hospital from January 2013 to June 2023.Patients were categorized into two groups based on the presence or absence of femoral head necrosis within one year post-operation:the necrosis group and the non-necrosis group.Univariate analysis,Lasso regression,and multivariate Logistic regression techniques were employed to identify the determinants of femoral head necrosis.A nomogram prediction model was constructed using R language's"rms"package,version 4.0.The receiver operating characteristic curve was used to evaluate the discriminatory ability of the model.The Hosmer-Lemeshow test was used to evaluate the goodness of fit of the model,and the decision curve analysis was used to determine its clinical application benefits.Internal validation of the study was conducted using the Bootstrap method,involving 1 000 repeated samplings.To delve deeper into the primary factors influencing femoral head necrosis post-internal fixation of the femoral neck,this paper employed the SHAP method for data set analysis.RESULTS AND CONCLUSION:(1)The risk factors leading to femoral head necrosis in the short term after cannulated screw fixation of femoral neck fractures include:smoking,diabetes,Garden classification,fracture line location,reduction quality,age,and operation time.(2)The prediction model demonstrated robust performance,evidenced by an area under the curve of 0.940(95％Confidence Interval:0.903 to 0.977),indicating a high level of prediction accuracy.The model achieved a sensitivity of 90.2％and a specificity of 87.6％,indicating that its diagnostic performance was stable.The Hosmer-Lemeshow goodness-of-fit test yielded a chi-square value of 6.593 with a P-value of 0.581,confirming that the model's predictions closely align with the observed outcomes.(3)The calibration curve of the model also performed well,and its overall trend was very close to the ideal curve,further proving the high accuracy of the model.(4)The internal validation was carried out by the Bootstrap method with 1 000 repeated samplings,and the area under the curve of the model internal validation was still as high as 0.939,proving that the model had good stability.(5)Through the decision curve,it is found that within the probability threshold range of 1％to 92％,the model can obtain the maximum net benefit value.(6)The SHAP analysis results show that among the risk factors analyzed in this study,the location of the fracture line serves as the most significant predictor of femoral head necrosis following internal fixation with cannulated screws in femoral neck fractures,and subcapital fractures are extremely prone to femoral head necrosis after surgery.(7)It is concluded that the validated prediction model demonstrates strong discriminative power and reliability,offering practical clinical utility.It serves as a useful reference tool for short-term risk assessment of femoral head necrosis following internal fixation of femoral neck fractures.

BACKGROUND:Due to the complex movement of the scapula,which is a six-degree-of-freedom activity in three-dimensional space,it is difficult to measure it accurately using traditional methods.The image and model matching technology based on dual-plane X-ray is a three-dimensional measurement method that has gradually developed and matured in recent years.Two high-speed cameras are used to project and shoot from orthogonal directions.Compared with a single perspective,this method has advantages in observation range and reduction of out-of-plane errors,and is suitable for the study of scapula kinematics.OBJECTIVE:X-ray biplane and image-model registration technology were used to explore the differences in scapular kinematics between normal individuals and patients with rotator cuff tears,providing a basis for the treatment and rehabilitation of rotator cuff tear patients.METHODS:From April 2023 to January 2024,10 patients with normal shoulders and 10 patients with rotator cuff tears who met the inclusion criteria were enrolled from Guanghua Hospital Affiliated to Shanghai University of Traditional Chinese Medicine.The subjects underwent a shoulder CT scan to create a 3D model and a local scapular coordinate system.X-ray biplane images were taken during shoulder abduction with two C-arm machines.The 2D and 3D images were registered to compare scapular kinematic differences between the two groups at 0°,15°,30°,45°,60°,75°,and 90° of abduction,including scapular rotation angle and displacement distance.RESULTS AND CONCLUSION:(1)During shoulder abduction,the scapula of both groups showed upward rotation,but the upward rotation of the rotator cuff tear group was greater than that of the control group,and the difference was significant when the abduction was 30°-90°(P＜0.01).At the same time,the scapula internal rotation of both groups gradually increased,but the rotator cuff tear group was significantly greater than the control group when the abduction was 45°-90°(P＜0.01).In addition,the anteroposterior tilt of the scapula of the two groups was significantly different when the abduction was 15°-90°(P＜0.01).The scapula posterior tilt of the control group gradually increased during abduction,while the scapula of the rotator cuff tear group tilted forward except for a slight posterior tilt at 15°-30° abduction.(2)In terms of displacement,the upward displacement of the rotator cuff tear group was less than that of the control group during abduction,and the difference was significant at 15°-90°(P＜0.05),but there was no significant difference in lateral and anterior-posterior displacement between the two groups(P＞0.05).(3)Rotator cuff tear can cause scapular dyskinesis,characterized by increased upward rotation,internal rotation,and abnormal forward tilt during shoulder abduction.Identifying and addressing scapular dyskinesis is crucial for treating rotator cuff tear.

BACKGROUND:The local immune microenvironment plays an important regulatory role in the process of bone formation,and the immune system is intricately linked to the skeletal system.OBJECTIVE:To systematically review the promotion of bone regeneration from three aspects:immune cell regulation of microenvironment,regulation of immune response by small extracellular vesicles,and induction of immune response by bone biomaterials,and to elucidate the immune regulatory mechanisms involved in bone regeneration.METHODS:Relevant literature was retrieved from PubMed,CNKI,WanFang Database,and VIP Database,using the search terms of"osteoimmunology,immune microenvironment,small extracellular vesicles,bone regeneration,bone tissue repair,biomaterials,and tissue engineering"in English and Chinese.Repeat and irrelevant literature was screened and removed,and 92 articles that met the criteria were selected for intensive reading and review.RESULTS AND CONCLUSION:Multiple immune cells and bone cells are in the same microenvironment,and immune cells can regulate the differentiation and activity of bone cells,collectively forming an immune microenvironment that affects bone regeneration.Neutrophils can significantly reduce local inflammatory responses in the early stages of bone injury,creating a favorable microenvironment for bone regeneration.M1 macrophages can clear foreign bodies and reduce early inflammatory responses,while M2 macrophages can promote the expression of osteogenic markers and factors,playing an important role in the repair process of bone injury.B cells and T cells can directly or indirectly affect the generation and activity of osteoblasts and osteoclasts,regulate bone metabolism,and promote bone regeneration.Extracellular vesicles of small cells regulate the local immune microenvironment through paracrine secretion,promoting bone formation and angiogenesis at the site of bone injury.The metal ions,surface hydrophilicity,porosity,pore size,surface morphology,and surface roughness on the surface of biomaterials can directly regulate local immune responses,and have anti-inflammatory,angiogenic,and osteogenic effects,thereby accelerating bone regeneration.

BACKGROUND:With the development of the concept of minimally invasive surgery,lumbar posterior dynamic internal fixation has become the mainstream operation for the treatment of diseases caused by intervertebral disc degeneration.OBJECTIVE:To review the latest progress of lumbar posterior dynamic internal fixation in the treatment of lumbar degenerative diseases and postoperative intervertebral disc rehydration.METHODS:The relevant literature published in CNKI,WanFang,and PubMed databases from 2010 to 2025 was searched with the Chinese and English search terms"lumbar spine,dynamic internal fixation,intervertebral disc degeneration,Coflex system,Dynesys system,In-space system,PercuDyn system,intervertebral disc rehydration,crushing stress."By reading the articles,we eliminated the literature with little relevance to the article topic,poor quality and outdated content,and finally 65 articles were included for summary.RESULTS AND CONCLUSION:(1)Although the main surgical method for the treatment of disc degeneration is still the traditional open surgical method of implantation,posterior lumbar dynamic internal fixation has made great progress.(2)Posterior lumbar dynamic fixation can be divided into open dynamic fixation system and percutaneous dynamic fixation system.Each system can be divided into interspinous dynamic internal fixation system and pedicle dynamic internal fixation system according to the different fixation positions.According to the design of specific instruments and the differences of operation methods in the surgery,different operation methods have been derived.At present,the focus of research at home and abroad is on open dynamic internal fixation system.(3)Under the premise that the clinical effect of posterior lumbar dynamic internal fixation is better than that of traditional interbody fusion surgery,it can cause the rehydration phenomenon of postoperative lumbar intervertebral disc,and further improve the long-term postoperative efficacy of patients.

OBJECTIVE:Based on different algorithms of machine learning,the prediction model of lumbar disc herniation has become a trend and hot spot in the development of precision medicine.However,there is limited evidence on the reporting quality and methodological quality of prediction models of lumbar disc herniation outcomes using machine learning.This article is aimed to explore the performance of machine learning algorithms in predicting the prognosis of lumbar disc herniation by comprehensively analyzing the report quality and risk of bias of previous studies that developed and validated prognosis prediction models based on machine learning through a comprehensive literature search,in order to explore the performance of machine learning algorithms in predicting the prognosis of lumbar disc herniation.METHODS:The databases of CNKI,WanFang,VIP,SinOMED,PubMed,Web of Science,Embase,and The Cochrane Library were searched by computer.Studies on the use of machine learning to develop(and/or validate)prognostic prediction models for lumbar disc herniation were collected from the inception of the database to December 31,2023.Two researchers independently screened the literature,extracted data,and assessed the risk of bias of the included studies.The reporting quality and risk of bias of the included studies were assessed by the Multivariable Transparent Reporting of Predictive Models(TRIPOD)statement and the Predictive Model Risk of Bias Assessment Tool(PROBAST).The results of the evaluation were analyzed using descriptive statistics and visual charts.RESULTS:(1)A total of 23 articles were included,and the TRIPOD compliance of each study ranged from 11％to 87％,with a median compliance of 54％.The quality of reporting of titles,detailed descriptions of treatment measures,blinding of predictors,handling of missing data,details of risk stratification,specific procedures for enrollment,model interpretation,and model performance was mostly poor,with TRIPOD adherence rates ranging from 4％to 35％.(2)Of all included studies,61％had a high risk of bias and 39％had an unclear overall risk of bias.The area under the curve,accuracy,sensitivity and specificity were used to evaluate the performance of the model.The areas under the curve of 20 models were reported,ranging from 0.561 to 0.999.Three models reported the accuracy of the model,ranging from 82.07％to 89.65％.(3)Among all included studies,the statistical analysis domain was most often assessed as having a high risk of bias,mainly due to the small number of valid samples,the selection of predictors based on univariate analysis and the lack of calibration and discrimination assessment of the model in the study.CONCLUSION:These results indicate that machine learning can achieve good predictive ability in the development and validation of prognostic models for lumbar disc herniation.The commonly used algorithms include regression algorithm,support vector machine,decision tree,random forest,artificial neural network,naive Bayes and other algorithms.Reasonable algorithms combined with clinical practice can improve the accuracy of prognosis prediction of lumbar disc herniation.However,the reporting and methodological quality of prognosis prediction models based on machine learning are poor,the prediction performance of different models varies greatly,and the generalization and extrapolation of research models are unclear.There is an urgent need to improve the design,implementation and reporting of such studies.To promote the application of machine learning in the clinical practice of lumbar disc herniation prediction models,it is necessary to comprehensively consider various predictors related to the prognosis of the disease before modeling,and strictly follow the relevant standards of PROBAST tool during modeling.

BACKGROUND:The number of patients receiving total knee arthroplasty has been increasing globally each year.Pain management is a crucial aspect following total knee arthroplasty,as effective pain control can facilitate early mobilization,reduce complications,enhance patient satisfaction,and accelerate the rehabilitation process.OBJECTIVE:To construct a visual map of post-total knee arthroplasty pain,understand the international research status and trends in this field,and provide a reference for future studies.METHODS:Relevant research articles on post-total knee arthroplasty pain were retrieved from the CNKI,WanFang Data,and Web of Science core databases,covering the period from January 2000 to December 2023.The CiteSpace software(version 6.2.3)was used to analyze the annual publication output,authors,institutions,countries,keywords,and references.Utilizing R programming language(version 4.4.1),a database was established to create line charts and bar graphs.RESULTS AND CONCLUSION:(1)Our analysis included 3 796 publications,predominantly in Chinese(3 509 articles)with the remainder in English(287 articles).(2)The United States was the most productive country in English literature,with Harvard University leading institutional output.Guangzhou University of Chinese Medicine was the top publishing institution in Chinese literature.(3)Keyword clustering identified"quality of life,""phobia,"and"acupuncture"as emerging focal points in Chinese literature,while"satisfaction"and"psychological factors"were prominent in English literature over the past five years.Co-occurrence and clustering analysis revealed dense internal connections among institutions,authors,and publications,but sparse external collaborations.(4)The study's bias on visualization analysis may have introduced bias by excluding less influential papers.(5)Regarding research hotspots,domestic research emphasized the efficacy and exploration of analgesic methods,in contrast to international research that focused on pain mechanism subtyping and analgesic drug innovation.Future research is expected to trend towards traditional Chinese medicine for postoperative pain,multimodal analgesia,and the investigation and prevention of pain typing mechanisms.

BACKGROUND:The quadriceps strength of patients with osteoporosis and sarcopenia is significantly reduced,which can further reduce the function of the knee joint,affect the function of the lower limbs and even lead to a decrease in whole-body coordination.It is speculated that a reasonable quadriceps training program and personalized guidance are beneficial to the recovery of knee joint function in patients with osteoporosis and sarcopenia.OBJECTIVE:To observe the effect of short-term moderate-intensity resistance rehabilitation training on the mass and function of the quadriceps and knee joint function in patients with osteoporosis and sarcopenia.METHODS:Using the integrated physical examination and rehabilitation model,375 patients with osteoporosis and sarcopenia were screened at the Health Management Center of Shanghai Public Health Clinical Center.They underwent 12 weeks of combined/comprehensive exercise rehabilitation based on resistance exercise,including quadriceps resistance isotonic and isometric contraction training twice a week(3-5 sets each time,10-15 minutes per set)and aerobic exercise/balance exercise two or three times a week(30 minutes each time).Assessments and data collection were performed before rehabilitation training,12 weeks after rehabilitation training,and at follow-up 12 weeks after stopping rehabilitation training,mainly including knee joint range of motion and proprioception,quadriceps muscle strength,and cross-sectional area(magnetic resonance imaging results),pain,knee joint function(Hospital for Special Surgery score)and walking function("up-and-go"time and 6 m pace test results)as well as the patient's psychological status assessment.RESULTS AND CONCLUSION:All 375 patients completed 12 weeks of rehabilitation training and 12 weeks of follow-up without any adverse events.(1)Compared with before training,the patients' gait speed and knee range of motion increased significantly after 12 weeks of rehabilitation training(P＜0.01),the time of"stand-to-walk"decreased(P＜0.01),and the proprioception of the knee joint and the strength of the quadriceps femoris were significantly improved(P＜0.01);and at the follow-up visit 12 weeks after stopping training,the above indicators and functions of the patients were well maintained(P＞0.05).(2)Magnetic resonance imaging results showed that the effective cross-sectional area of the quadriceps femoris did not improve significantly after 12 weeks of rehabilitation training(P＞0.05);but the Hospital for Special Surgery score of knee joint function increased significantly(P＜0.01),and the visual analog pain scale score decreased significantly(P＜0.01),suggesting that this may be related to the improvement of quadriceps femoris quality by resistance rehabilitation training.(3)The results of the Hospital Anxiety and Depression Scale score showed that the anxiety and depression scores of the patients continued to decrease,both at 12 weeks of rehabilitation training and at 12 weeks after stopping training(P＜0.01).It is suggested that resistance rehabilitation training of the quadriceps can help patients with osteoporosis and sarcopenia to restore quadriceps muscle strength,increase range of motion,improve proprioception and joint stability,thereby enhancing knee joint function,reducing pain,improving depression and anxiety,and to a certain extent promoting the coordinated recovery of the musculoskeletal system.