Objective To develop a deep learning system for CT images to assist in the diagnosis of thoracolumbar fractures and analyze the feasibility of its clinical application. Methods Collected from West China Hospital of Sichuan University from January 2019 to March 2020, a total of 1256 CT images of thoracolumbar fractures were annotated with a unified standard through the Imaging LabelImg system. All CT images were classified according to the AO Spine thoracolumbar spine injury classification. The deep learning system in diagnosing ABC fracture types was optimized using 1039 CT images for training and validation, of which 1004 were used as the training set and 35 as the validation set; the rest 217 CT images were used as the test set to compare the deep learning system with the clinician’s diagnosis. The deep learning system in subtyping A was optimized using 581 CT images for training and validation, of which 556 were used as the training set and 25 as the validation set; the rest 104 CT images were used as the test set to compare the deep learning system with the clinician’s diagnosis. Results The accuracy and Kappa coefficient of the deep learning system in diagnosing ABC fracture types were 89.4% and 0.849 (P<0.001), respectively. The accuracy and Kappa coefficient of subtyping A were 87.5% and 0.817 (P<0.001), respectively. Conclusions The classification accuracy of the deep learning system for thoracolumbar fractures is high. This approach can be used to assist in the intelligent diagnosis of CT images of thoracolumbar fractures and improve the current manual and complex diagnostic process.
ObjectiveTo investigate the effectiveness of retroperitoneal laparoscopic approach combined with anterolateral mini-incision for lumbar spine tuberculosis. MethodsA retrospective analysis was made on the cl inical data of 22 patients with lumbar spine tuberculosis undergoing focus clearance, fusion, and internal fixation by retroperitoneal laparoscopic approach combined with anterolateral mini-incision between June 2006 and June 2012. There were 14 males and 8 females, with an average age of 42.6 years (range, 26-57 years) and with a mean disease duration of 7.3 months (range, 3-10 months). There were 17 patients with single-level spinal tuberculosis (L1, 2 in 3, L2, 3 in 6, L3, 4 in 4, L4, 5 in 2, and L5 in 2) and 5 patients with double-level spinal tuberculosis (L1-3 in 2 and L2-4 in 3). The preoperative Cobb's angle of lumbar spine was 5-28° (mean, 20°). In 6 patients having compression symptom, 4 cases were rated as grade D and 2 as grade C according to Frankel classification. The operative time, intraoperative blood loss, and postoperative complications were recorded. At last follow-up, the neurologic function was assessed according to Frankel grade, the Cobb's angle after operation was measured on lumbar lateral X-ray film; the efficacy was evaluated according to Nakai criteria, and the fusion was evaluated according to Suk criteria. ResultsAll operations were successfully completed. The operation time was 110-250 minutes (mean, 140 minutes), and intraoperative blood loss was 120-280 mL (mean, 180 mL). The symptoms of femoral nerve injury and sympathetic nerve injury occurred in 1 case respectively and was relieved at 1-3 weeks after operation. All incisions healed by first intention. The patients were followed up 16-50 months (mean, 21 months). During the follow-up period, no loosening or breakage of implants and no tuberculosis recurrence were found. At last follow-up, the nerve function was recovered to grade E in the others except 1 case at grade D. The Cobb's angle was 2-16° (mean, 7.8°). According to Nakai criteria for efficacy evaluation, the results were excellent in 9 cases, good in 10 cases, and fair in 3 cases, with an excellent and good rate of 86.4%. The bony fusion rate was 95.5% (21/22) according to Suk criteria. ConclusionRetroperitoneal laparoscopic approach combined with anterolateral mini-incision for lumbar spine tuberculosis is a safe and effective approach with minimal invasion and less complications.
ObjectiveTo explore the effectiveness of pedicle screw fixation combined with non-fusion technology for the treatment of thoracolumbar fracture (AO type A) through Wiltse paraspinal approach. MethodsBetween March 2011 and December 2012, 35 cases of thoracolumbar fractures were treated with pedicle screw fixation combined with non-fusion technology by Wiltse paraspinal approach. There were 27 males and 8 females, aged from 19 to 51 years (mean, 39.7 years). The time from injury to operation varied from 3 to 15 days (mean, 5.9 days). The causes of injury were traffic accident in 17 cases, falling from height in 11 cases, and crush trauma in 7 cases. All fractures were single-segment fracture, including T8 in 1 case, T9 in 2 cases, T10 in 2 cases, T11 in 3 cases, T12 in 12 cases, L1 in 10 cases, L2 in 4 cases, and L3 in 1 case. According to AO classification, there were 17 type A1 fractures (compression fracture), 3 type A2 fractures (splitting fracture), and 15 type A3 fractures (burst fracture). Based on American Spinal Injury Association (ASIA) spinal cord injury grade, all cases were in grade E before operation. Perioperative parameters were recorded; the anterior vertebral height and kyphotic Cobb angle of vertebral bodies were measured before and after operation to evaluate the effect of correction. ResultsThe mean operating time was 74 minutes; the mean blood loss was 125 mL; and the mean drainage volume was 51 mL. Skin necrosis of incision occurred in 2 cases and was cured after dressing change; primary healing of incision was obtained in the others. All patients were followed up 15-24 months (mean, 17.3 months). No loosening or breakage of internal fixation was found. The internal fixator was removed at 12-19 months after operation (mean, 15 months). There were significant differences in Cobb's angle and anterior vertebral body height between before operation and immediately after operation, before internal fixator removal as well as at last follow-up (P < 0.05). There was no significant difference in anterior vertebral body height among the postoperative time points (P > 0.05). There was significant difference in Cobb's angle between immediately after operation and before internal fixator removal as well as at last follow-up (P < 0.05), but the difference was not significant between before internal fixator removal and at last follow-up (P > 0.05). The motion of fixed segment was restored after internal fixator removal. ConclusionIt is an effective method of pedicle screw fixation combined with non-fusion technology through Wiltse paraspinal approach for the treatment of thoracolumbar fracture (AO type A). The method has the advantages of simple operation and less trauma. It can effectively rebuild the height of vertebral body and correct kyphotic deformity.
Objective To investigate the effect of the sequence of intermediate instrumentation with long screws and distraction-reduction on mild to moderate thoracolumbar fractures treated by posterior open and short-segmental fixation. MethodsThe clinical data of 68 patients with mild to moderate thoracolumbar burst fractures who met the selection criteria between January 2016 and June 2019 were retrospectively analyzed. The patients were divided into group ISDRF (intermediate screws then distraction-reduction fixation, 32 cases) and group DRISF (distraction-reduction then intermediate screws fixation, 36 cases) according to the different operation methods. There was no significant difference between the two groups in age, gender, body mass index, fracture segment, cause of injury, and preoperative load-sharing classification score, thoracolumbar injury classification and severity score, vertebral canal occupational rate, back pain visual analogue scale (VAS) score, anterior height of fractured vertebra, and Cobb angle (P>0.05). The operation time, intraoperative blood loss, complications, and fracture healing time were recorded and compared between the two groups. The vertebral canal occupational rate, anterior height of fractured vertebra, kyphosis Cobb angle, and back pain VAS score before and after operation were used to evaluate the effectiveness. Results There was no significant difference in intraoperative blood loss and operation time between the two groups (P>0.05). No vascular or spinal nerve injury and deep infections or skin infections occurred in both groups. At 1 week after operation, the vertebral canal occupational rate in the two groups was significantly improved when compared with that before operation (P<0.05), no significant difference was found in the difference of vertebral canal occupational rate before and after operation and improvement between the two groups (P>0.05). The patients in both groups were followed up 18-24 months, with an average of 22.3 months. All vertebral fractures reached bone union at 6 months postoperatively. At last follow-up, there was no internal fixation failures such as broken screws, broken rods or loose screws, but there were 2 cases of mild back pain in the ISDRF group. The intra-group comparison showed that the back pain VAS score, the anterior height of fractured vertebra, and the Cobb angle of the two groups were significantly improved at each time point postoperatively (P<0.05); the VAS scores at 12 months postoperatively and last follow-up were also improved when compared with that at 1 week postoperatively (P<0.05). At last follow-up, the anterior height of fractured vertebra in the ISDRF group was significantly lost when compared with that at 1 week and 12 months postoperatively (P<0.05), the Cobb angle had a significant loss when compared with that at 1 week postoperatively (P<0.05); the anterior height of fractured vertebra and Cobb angle in DRISF group were not significantly lost when compared with that at 1 week and 12 months postoperatively (P>0.05). The comparison between groups showed that there was no significant difference in the remission rate of VAS score between the two groups at 1 week postoperatively (P>0.05), the recovery value of the anterior height of fractured vertebra in ISDRF group was significantly higher than that in DRISF group (P<0.05), the loss rate at last follow-up was also significantly higher (P<0.05); the correction rate of Cobb angle in ISDRF group was significantly higher than that in DRISF group at 1 week postoperatively (P<0.05), but there was no significant difference in the loss rate of Cobb angle between the two groups at last follow-up (P>0.05). ConclusionIn the treatment of mild to moderate thoracolumbar burst fractures with posterior short-segment fixation, the instrumentation of long screws in the injured vertebrae does not affect the reduction of the fracture fragments in the spinal canal. DRISF can better maintain the restored anterior height of the fractured vertebra and reduce the loss of kyphosis Cobb angle during the follow-up, indicating a better long-term effectiveness.
ObjectiveTo summarize the experience in management of occult cerebrospinal fluid leakage (CSFL) in posterior thoracolumbar surgeries, and to explore the best drainage duration, as well as to analyse the ways to reduce the risk of CSFL. MethodsA retrospective analysis was made on the clinical data of 26 patients with occult CSFL in posterior thoracolumbar surgeries between January 2011 and January 2013. There were 15 males and 11 females, with the average age of 48.7 years (range, 36-59 years). Headache occurred in 19 cases, and 5 cases had nausea with 3 cases also having vomiting after operation. Drainage tube unobstructed and no CSFL from the skin incision were observed in 23 cases at the postoperative 2nd day, and the drainage pipe clamp test was performed at the 3rd day. Twenty-one patients had no CSFL and were given extubation; 2 cases having CSFL were given extubation after conservative treatments for 10 days. Three patients had CSFL with ineffective conservative treatments at the postoperative 2nd day, then received reoperation, incision suture, and drainage. At the postoperative 3rd day, if no CSFL was observed, these patients were given extubation and stayed in bed for 3-5 days. ResultsAll incisions healed and the healing time was 7-15 days (mean, 8 days). No incision infection, persistent CSFL, and other complications occurred. After extubation, headache, nausea, vomiting, and other symptoms were alleviated immediately. All patients were followed up 12-24 months (mean, 16 months). MRI at the postoperative 6th month showed no subcutaneous epidural pseudocyst. ConclusionThe quality of suturing is the key factor to prevent occult CSFL in posterior thoracolumbar surgery. Under the premise of good suture quality, extubation can be given at the postoperative 3rd day. Before extubation, the drainage pipe clamp test can be performed to make sure no CSFL and to reduce the risk of CSFL from the surgical incision after extubation.
Objective To explore decompression strategies for lateral lumbar spinal stenosis under unilateral biportal endoscopy (UBE) assistance. Methods A clinical data of 86 patients with lateral lumbar stenosis treated with UBE-assisted intervertebral decompression between September 2022 and December 2023 was retrospectively analyzed. There were 42 males and 44 females with an average age of 63.6 years (range, 45-79 years). The disease duration ranged from 6 to 14 months (mean, 8.5 months). Surgical levels included L2, 3 in 3 cases, L3, 4 in 26 cases, L4, 5 in 42 cases, and L5, S1 in 15 cases. According to Lee’s grading system, there were 21 cases of grade 1, 37 cases of grade 2, and 28 cases of grade 3 for lumbar spinal stenosis. Based on the location of stenosis and clinical symptoms, the 33 cases underwent interlaminar approach, 7 cases underwent interlaminar approach with auxiliary third incision, 26 cases underwent contralateral inclinatory approach, and 20 cases underwent paraspinal approach; then, the corresponding decompression procedures were performed. Visual analogue scale (VAS) score was used to evaluate lower back/leg pain before operation and at 1 and 3 months after operation, while Oswestry disability index (ODI) was used to evaluate spinal function. At 3 months after operation, the effectiveness was evaluated using the modified MacNab evaluation criteria. The spinal stenosis and decompression were evaluated based on Lee’s grading system using lumbar MRI before operation and at 3 months after operation. ResultsAll procedures were successfully completed with mean operation time of 95.1 minutes (range, 57-166 minutes). Dural tears occurred in 2 cases treated with interlaminar approach with auxiliary third incision. All incisions healed by first intention. All patients were followed up 3-10 months (mean, 5.9 months). The clinical symptoms of the patients relieved to varying degrees. The VAS scores and ODI of lower back and leg pain at 1 and 3 months after operation significantly improved compared to preoperative levels (P<0.05), and the indicators at 3 months significantly improved than that at 1 month (P<0.05). According to the modified MacNab evaluation criteria, the effectiveness at 3 months after operation was rated as excellent in 52 cases, good in 21 cases, and poor in 13 cases, with an excellent and good rate of 84.9%. No lumbar instability was detected on flexion-extension X-ray films during follow-up. The Lee’s grading of lateral lumbar stenosis at 2 days after operation showed significant improvement compared to preoperative grading (P<0.05). ConclusionFor lateral lumbar spinal stenosis, UBE-assisted decompression of the spinal canal requires the selection of interlaminar approach, interlaminar approach with auxiliary third incision, contralateral inclinatory approach, and paraspinal approach based on preoperative imaging findings and clinical symptoms to achieve better effectiveness.
In the present study, a finite element model of L4-5 lumbar motion segment was established based on the CT images and a combination with image processing software, and the analysis of lumbar biomechanical characteristics was conducted on the proposed model according to different cases of flexion, extension, lateral bending and axial rotation. Firstly, the CT images of lumbar segment L4 to L5 from a healthy volunteer were selected for a three dimensional model establishment which was consisted of cortical bone, cancellous bone, posterior structure, annulus, nucleus pulposus, cartilage endplate, ligament and facet joint. The biomechanical analysis was then conducted according to different cases of flexion, extension, lateral bending and axial rotation. The results showed that the established finite element model of L4-5 lumbar segment was realistic and effective. The axial displacement of the proposed model was 0.23, 0.47, 0.76 and 1.02 mm, respectively under the pressure of 500, 1 000, 1 500 and 2 000 N, which was similar to the previous studies in vitro experiments and finite element analysis of other people under the same condition. The stress distribution of the lumbar spine and intervertebral disc accorded with the biomechanical properties of the lumbar spine under various conditions. The established finite element model has been proved to be effective in simulating the biomechanical properties of lumbar spine, and therefore laid a good foundation for the research of the implants of biomechanical properties of lumbar spine.
Objective To compare the surgical efficacy of different operating methods for treating old thoracolumbarfracture with spinal cord injury. Methods From September 2000 to March 2006, 34 cases of old thoracolumbar fractures with spinal cord injury were treated. Patients were divided into 2 groups randomly. Group A (n=18): anterior approach osteotomy, il iac bone graft and internal fixation were used. There were 10 males and 8 females with the age of 17-54 years. The apex level of kyphosis was T11 in 2 cases, T12 in 5 cases, L1 in 8 cases and L2 in 3 cases. The average preoperative Cobb angle of kyphosis was (36.33 ± 3.13)°, and the average preoperative difference in height between anterior and posterior of involved vertebra was (22.34 ± 11.61) mm. Neurological dysfunction JOA score was 10.44 ± 1.12. Group B (n=16): transpedicular posterior decompression and internal fixation were used. There were 8 males and 8 females with the age of 18-56 years. The apex level of kyphosis was T11 in 2 cases, T12 in 6 cases, L1 in 7 cases and L2 in 1 case. The preoperative Cobb angle of kyphosis was (38.55 ± 4.22)°, and the preoperative difference in height between anterior and posterior of involved vertebra was (20.61 ± 10.22) mm. Neurological dysfunction JOA score was 10.23 ± 2.23. Results All the patients were followed up for 9-46 months with an average of 13.5 months. Cobb angle was (12.78 ± 3.76)° in group A, which was improved by (24.23 ± 1.64)° campared to that of preoperation; and was (10.56 ± 4.23)° in group B, which was improved by (26.66 ± 1.66)°. JOA score was 14.21 ± 1.08 in group A, which wasimproved by 3.92 ± 1.33; and it was 13.14 ± 2.32 in group B, which was improved by 3.12 ± 1.95. The average postoperative difference between anterior height and posterior height of vertebral body in group A was (3.11 ± 1.06) mm, which was improved by (18.03 ± 2.14) mm; and it was (2.56 ± 1.33) mm in group B, which was corrected by (20.36 ± 3.78) mm. There were statistically significant differences in the above indexes between preoperation and postoperation in 2 groups (P lt; 0.01), but no significant differences between 2 groups (P gt; 0.05). In group A, pleural effusion occurred in 2 cases and local pulmonary collapse in 4 cases and intercostals neuralgia in 1 case. In group B, leakage of cerebrospinal fluid occurred in 3 cases. Conclusion Both anterior and posterior approach are capable of treating of the old thoracolumbar fracture with incomplete spinal cord injury and providing the satisfying result of deformation correction, neurological decompression and neurological functional recovery to a certain extent.
ObjectiveTo compare the effectiveness of short segmental pedicle screw fixation with and without fusion in the treatment of thoracolumbar burst fracture. MethodsA retrospective analysis was made on the clinical data of 57 patients with single segment thoracolumbar burst fractures, who accorded with the inclusion criteria between February 2012 and February 2014. The patients underwent posterior short segmental pedicle screw fixation with fusion in 27 cases (fusion group) and without fusion in 30 cases (non-fusion group). There was no significant difference in gender, age, cause of injury, time between injury and admission, fracture segment and classification, and neurologic function America Spinal Injury Association (ASIA) classification between 2 groups, which had the comparability (P > 0.05). The operative time, blood loss, and hospitalization days were compared between 2 groups. The height of the injured vertebra, the kyphotic angle, and the range of motion (ROM) were measured on the X-ray film. The functional outcomes were evaluated by using the Greenough low-back outcome score and the visual analogue scale (VAS) for back pain. The neurologic functional recovery was assessed by ASIA grade. ResultsThe operative time was significantly shortened and the blood loss was significantly reduced in the non-fusion group when compared with the fusion group (P < 0.05), but no significant difference was found in hospitalization days between 2 groups (P > 0.05). The patients were followed up for 2.0-3.5 years (mean, 3.17 years) in the fusion group and for 2-4 years (mean, 3.23 years) in the non-fusion group. X-ray films showed that 2 cases failed bone graft fusion, the fusion time was 12-17 weeks (mean, 15.6 weeks) in the other 25 cases. Complication occurred in 2 cases of the fusion group (1 case of incision deep infection and 1 case of hematoma at iliac bone donor site) and in 1 case of the non-fusion group (fat liquefaction); primary healing of incision was obtained in the others. The Cobb angle, the height of injured vertebrae showed no significant difference between 2 groups at pre-operation, immediate after operation, and last follow-up (P > 0.05). The ROM of injured vertebrae showed no significant difference between 2 groups at 1 year after operation (before implants were removed) (P > 0.05). The implants were removed at 1 year after operation in all cases of the non-fusion group, and in 11 cases of the fusion group. At last follow-up, the ROM of injured vertebrae in the non-fusion group was significantly higher than that in the fusion group (P < 0.05), but no significant difference was found in Greenough low-back outcome score, VAS score, and ASIA grade between 2 groups (P > 0.05). ConclusionFusion is not necessary when thoracolumbar burst fracture is treated by posterior short segmental pedicle screw fixation, which can preserve regional segmental motion, shorten the operative time, decrease blood loss, and eliminate bone graft donor site complications.