Objective:To observe the morphological characteristics of L 4, 5 facet joints in patients with degenerative lumbar spondylolisthesis (DLS) of different spinopelvic types based on Roussouly classification. Methods:We retrospectively analyzed 142 patients with DLS who visited the department of orthopaedics in the Affiliated Hospital of Southwest Medical University from August 2018 to May 2022. There were 33 males aged 65.0±10.7 years and 109 females aged 61.8±9.6 years. The following morphological parameters of the L 4, 5 facet joint were measured on the CT images: facet joint angle (FJA), pedicle facet angle (PFA), facet joint tropism (FT) and facet joint osteoarthritis (OA) degree; the sacral slope (SS), lumbar lordosis (LL) and percentage of L 4 slip distance (SDP) were measured on preoperative standing neutral lumbar radiographs. According to the Roussouly classification, the patients were divided into four groups (type I, type II, type III, and type IV). The differences of morphological parameters of the facet joints and SDP were compared among the four groups, and the correlation between the FJA and PFA was analyzed. Results:There were 142 patients, including 28 type I, 50 type II, 43 type III, and 21 type IV according to the Roussouly classification. The SDPs of type I, type II, type III, and type IV were 19.1%±3.4%, 18.6%±3.9%, 21.7%±3.9%, 25.0%±2.4%, respectively. Except for types I and II, there were statistically significant differences in pairwise comparison among all other types ( P<0.05). The FJAs in type I and type II (31.4°±6.3°, 35.2°±6.8°) were larger than those in type III (28.4°±5.6°) and type IV (23.4°±4.5°), and the FJA in type III was larger than that in type IV. Conversely, the FJA in type I was smaller than that in type II. These differences were statistically significant ( P<0.05). The PFAs in type I and type II (113.9°±4.9°, 111.3°±5.6°) were smaller than those in type III (116.3°±4.4°) and type IV (121.8°±3.5°), and the PFA in type III was smaller than that in type IV, while, the PFA in type I was larger than that in type II. These differences were statistically significant ( P<0.05). The degree of OA in both type I and type II was lower than that in type III and type IV, with statistically significant differences ( P<0.05). However, there were no statistically significant differences in the degree of OA between type I and type II and between type III and type IV ( P> 0.05). Additionally, there were no statistically significant differences ( F=0.40, P=0.752) in the FT values among type I, type II, type III, and type IV (5.8°±2.3°, 5.6°±2.4°, 6.1°±1.8°, 5.9°±1.9°). Pearson correlation analysis showed that FJA was negatively correlated with PFA ( r=-0.68, P<0.001). Conclusion:In the slip segment of DLS, the facet joint morphology was part of the joint configuration in different spinopelvic types, not just the result of joint remodeling after DLS. Morphological characteristics of the facet joints and DLS interacted with each other.

Objective:To delineate the morphological features of pedicle-facet joints in lumbar spondylolysis patients, correlating these with spinopelvic parameters to explore their mechanisms and clinical implications.Methods:This study enrolled 121 patients with L 5 spondylolysis (IS group), 108 with L 4, 5 degenerative spondylolisthesis (DS group), and 100 with normal L 4, 5 but L 5S 1 lumbar disc herniation (NL group), who underwent radiography and multislice spiral CT from May 2020 to January 2023. Parameters including vertebral slip percentage (SP) and spinopelvic alignments, such as sacral slope and lumbar lordosis, were quantified using standing lateral lumbar radiographs. Morphological parameters of the L 4 and L 5 facet joints were measured on 3D reconstructed lumbar CT images, including the facet joint angle (FJA), pedicle-facet joint angle (PFA), facet joint osteoarthritis (OA), and facet joint tropism (FT). Results:The analysis revealed significant variances in SS and LL among the groups ( F=21.910, P<0.001; F=22.439, P<0.001). The IS group exhibited the highest SS and LL, followed by the DS and NL groups. Morphological assessments showed the largest L 4 FJA in the IS group, with progressive decreases in the DS and NL groups ( F=344.791, P<0.001). Conversely, L 4 PFA was greatest in the DS group ( F=193.725, P<0.001). Notably, L 4 OA was markedly more severe in the DS group compared to IS and NL groups ( H=467.925, P<0.001), with no significant disparity between IS and NL groups ( P>0.05). Correlation analyses within each cohort highlighted a negative association of sacral slope and lumbar lordosis with facet joint angles, yet a positive correlation with pedicle-facet joint angles both with statistical significance ( P<0.05). Furthermore, L 4 facet joint angles were consistently smaller than those at L 5, and L 4 pedicle-facet joint angles were larger than L 5 ( P<0.05). Osteoarthritis at L 5 was more pronounced in the IS group compared to L 4 ( Z=7.043, P<0.001), a trend inversely observed in the DS group ( Z=11.868, P<0.001), while the NL group showed no significant osteoarthritic variance between levels ( Z=0.556, P=0.578). Conclusion:Patients with lumbar spondylolysis demonstrate elevated sacral slope and lumbar lordosis, indicative of increased localized biomechanical stress in the lumbar spine. These alterations in the morphology of the pedicle-facet joints highlight the distinctive structural adaptations and potential strain distributions within this cohort.

BACKGROUND:Hyperuricemia is a common metabolic disease,and the main clinical manifestation of patients with hyperuricemia is the formation of uric acid crystals leading to gout.Previous studies have only reported that uric acid crystals lead to intervertebral disc degeneration,but there are fewer studies on the correlation between hyperuricemia and intervertebral disc degeneration. OBJECTIVE:To retrospectively analyze the characteristics of intervertebral disc degeneration in patients with hyperuricemia and the correlation between serum uric acid level and intervertebral disc degeneration. METHODS:A retrospective analysis was performed in all patients diagnosed with intervertebral disc degeneration admitted at the Department of Orthopedics,the Affiliated Hospital of Southwest Medical University from January 2021 to December 2022.There were 97 hyperuricemia patients in the hyperuricemia group and 194 non-hyperuricemia patients in the control group according to sex and age in a ratio of 1:2.Blood uric acid test results were collected,and Pfirrmann scoring was performed for the degree of disc degeneration in patients based on the whole spinal MRI images.The difference in the degree of disc degeneration between the two groups was compared,and the correlation between the serum uric acid level and the degree of intervertebral disc degeneration was analyzed. RESULTS AND CONCLUSION:The Pfirrmann score in the hyperuricemia group was higher than that in the control group,and the total number of disc degeneration in the hyperuricemia group was also significantly higher than that in the control group(P<0.05).Spearman correlation analysis showed that the degree of disc degeneration in male patients was positively correlated with serum uric acid level at many spinal segments in the hyperuricemia group(C3/4:r=0.317,C4/5:r=0.333,C5/6:r=0.309,L2/3:r=0.443,P<0.05);the degree of disc degeneration in female patients was also positively correlated with serum uric acid level(C3/4:r=0.354,C4/5:r=0.388,C6/7:r=0.312,T7/8:r=0.282,T9/10:r=0.305,T11/12:r=0.277,L4/5:r=0.319,L5-S1:r=0.367,P<0.05).In the control group,there was no significant correlation between the degree of disc degeneration and serum uric acid level in male and female patients(P>0.05).To conclude,in patients with hyperuricemia,the higher serum uric acid level indicates the more serious intervertebral disc degeneration.Therefore,hyperuricemia is one of the risk factors for intervertebral disc degeneration.

Objective To propose a classification method for ultrasound images of pedicle screw canals based on radiomics analysis,and to evaluate the integrity of the screw canal.Methods With thoracolumbar spine specimens from 4 fresh cadavers,50 pedicle screw canals were pre-established and ultrasound images of the canals were acquired.A total of 2 000 images(1 000 intact and 1 000 damaged canal samples)were selected.The dataset was randomly divided in a 4∶1 ratio using 5-fold cross-validation to form training and testing sets(consisting of 1 600 and 400 samples,respectively).Firstly,the optimal radius of the region of interest was identified using the Otsu's thresholding method,followed by feature extraction using pyradiomics.Principal component analysis and the least absolute shrinkage and selection operator algorithm were employed for dimensionality reduction and feature selection,respectively.Subsequently,3 machine learning models(support vector machine[SVM],logistic regression,and random forest)and 3 deep learning models(visual geometry group[VGG],ResNet,and Transformer)were used to classify the ultrasound images.The performance of each model was evaluated using accuracy.Results With a region of interest radius of 230 pixels,the SVM model achieved the highest classification accuracy of 96.25%.The accuracy of the VGG model was only 51.29%,while the accuracies of the logistic regression,random forest,ResNet,and Transformer models were 85.50%,80.75%,80.17%,and 75.18%,respectively.Conclusion For ultrasound images of pedicle screw canals,the machine learning model performs better than the deep learning model as a whole,and the SVM model has the best classification performance,which can be used to assist physicians in diagnosis.

BACKGROUND:Osteoporotic vertebral fractures are the most common complication in patients with osteoporosis.As a new imaging technique,spine magnetic resonance imaging(MRI)is much more sensitive than X-ray film in the diagnosis of osteoporotic vertebral fractures.However,total spine MRI is costly and takes a long time to scan.Therefore,there is no consensus on whether all patients with osteoporotic vertebral fractures need to undergo total spine MRI scan and which patients need to undergo total spine MRI. OBJECTIVE:To analyze the distribution characteristics of vertebral fractures and explore their clinical significance by observing the whole spine MRI data of osteoporotic vertebral fractures patients. METHODS:Data of cases and MRI images of all patients diagnosed with fresh osteoporotic vertebral fractures who visited the Department of Orthopedics,Affiliated Hospital of Southwest Medical University from August 2018 to September 2022 were retrospectively analyzed.903 patients were included in the study based on inclusion and exclusion criteria.General information(age,gender,and body mass index),medical history characteristics(duration of illness,history of trauma surgery,percussion pain area,and pain score)were collected.The characteristics of vertebral fractures were analyzed through whole spine magnetic resonance imaging.Firstly,based on the number of vertebral fractures in patients,they were divided into the single vertebral fracture group(484 cases)and the multi-vertebral fracture group(419 cases),and the differences were analyzed between the two groups.Then,based on whether the farthest interval between the fractured vertebrae was greater than or equal to 5,the multi vertebral fracture group was further divided into two subgroups.Among them,Group A(the farthest interval between the fractured vertebrae was less than 5)contained 306 cases;Group B(with the farthest interval between fractured vertebral bodies greater than 5)included 113 cases.The differences were analyzed between two subgroups. RESULTS AND CONCLUSION:(1)Among 903 patients,419 patients(46.4%)had more than two fractured vertebrae.There were 654 patients(72.4%)with thoracolumbar fractures,and 54 patients(6%)with fractures in the thoracic plus lumbar region and the entire thoracic to lumbar region.In group B,96.5%of patients had multiregional percussion pain.(2)Compared with the patients in the single vertebral fracture group and the multi-vertebral fracture group,there were significant differences in bone mineral density,whether the medical history was greater than or equal to 1 month,the history of low energy injury,and the distribution and number of axial percussion pain areas in the spine during physical examination between the two groups(P<0.05).Age,gender,body mass index,whether there was underlying disease,pain visual analog scale score,whether there was a history of elderly thoracolumbar fracture,and whether there was a history of thoracolumbar surgery,and the number of fractured vertebrae had no statistical significance(P>0.05).(3)There were statistically significant differences between the Groups A and B in bone mineral density,the distribution and quantity of percussion pain area,and the history of low energy injury(P<0.05).There were no significant differences in age,gender,history of old fractures,visual analog scale score,body mass index,whether the medical history was longer than or equal to 1 month,history of underlying diseases,and history of thoracolumbar surgery between the two groups(P>0.05).(4)Patients with multiple low-energy trauma history,history of more than 1 month,multiple percussion pain,and the lower bone mineral density should be alert to the occurrence of multiple vertebral fracture and jump fracture.We recommend the whole spinal MRI for these patients.