A new fixator for spine was designed to restore the stability of spine in improving the treatment of thoraco-lumbar dislocation. This instrument was composed of six nails, two longitudinal connecting rods and two transverse connecting rods. On the surface of the nails, there were furrows engraved, instead of screw thread. It fixed the spine through pedicle of vertebra from the posterior approach. The fixed vertebrae were limited between two vertebrae. From 1989 th 1995, twelve patients with fracture-dislocation of thoraco-lumbar spine were reduced with this instrument. After four years follow-up, it showed that the deformity was corrected and the spine firmly fixed. Compared with Dick’s screws, it had the following advantages such as simple manipulation, increased strergth of nails and minimal damage to tissue during operation.
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.
Objective To explore the effectiveness of percutaneous pedicle screw fixation on the indirect reduction of posterosuperior fracture fragment in the thoraculumbar burst fractures. Methods Patients with thoracolumbar fractures treated in the Fourth People’s Hospital of Zigong from September 2017 to September 2019 were collected retrospectively. All patients were treated with percutaneous pedicle screw fixation. The main observation indexes before operation, 3 days after operation and 1 year after operation were compared, including the height ratio of the anterior margin of fractured vertebra, the inversion angle of posterosuperior fracture fragment, the fragment displacement, the occupancy rate of spinal canal, the Cobb angle of kyphosisat, Visual Analogue Scale (VAS) and Oswestry Disability Index (ODI). Results A total of 38 patients were included. All patients were followed up for more than 1 year. During the follow-up period, there were no complications such as nerve injury, incision infection, internal fixation loosening or fracture. The operation time was (91.7±10.4) min, the amount of intraoperative bleeding was (94.3±19.5) mL, and the length of surgical incision was (9.3±1.8) cm. The height ratio of the anterior margin of fractured vertebra, the inversion angle of posterosuperior fracture fragment, the fragment displacement, the occupancy rate of spinal canal, the Cobb angle of kyphosisat 3 days after operation were significantly improved compared with those before operation (P<0.05); the height ratio of the anterior margin of fractured vertebra, the occupancy rate of spinal canal, and the Cobb angle of kyphosisat 1 year after operation were also significantly improved compared with those before operation (P<0.05); the height ratio of the anterior margin of fractured vertebra and the occupancy rate of spinal canalat 1 year after operation were significantly improved than those 3 days after operation (P<0.05), but the Cobb angle of kyphosis 1 year after operation was significantly lost than that 3 days after operation (P<0.05). The VAS score and ODI index 3 days and 1 year after operation were significantly improved compared with those before operation (P<0.05), and the VAS score and ODI index 1 year after operation were improved compared with those 3 days after operation (P<0.05). Conclusion The percutaneous pedicle screw fixation can effectively reduce the retropulsed bone fragment indirectly and restore the Cobb angle of kyphosis of the thoraculumbar burst fractures without neurological deficit, and at the same time reduce the operation time and surgical trauma.
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.
Objective To evaluate lumbar laminotomy and replantation in prevention of spinal unstability and peridural adhesion after laminectomy.Methods From February 1995 to March 2001,a total of 169 patients(96 males, 73 females,aged 22-63) with lesions in the lumbar vertebral canals underwent surgery, in which the lesions were removed afterlaminectormy and then the excised laminae were replanted. Results The follow-up for 5-9 years showed that all the patients had no complications after the lesions were removed. According to the evaluation criteria formulated by WANG Yongti，81 patients had an excellent result, 67 had a good result, 19 had a fair result, and2 had a poor result. 87.6% of the patients obtained quite satisfactory results.The X-ray films demonstrated that the replanted laminae obtained bony healing and the spine was stable. The CT scanning demonstratedthat the canals were enlarged with a smooth and glossy interior. Conclusion Lumbar laminotomy and replantation is reasonable in design and convenient in performance, which can be promoted as a basic operation in spinal surgery.
To evaluate the method and effectiveness of anterior focus clearance with autograft bone fusion and internal fixation in treating of adjacent multivertebral tuberculosis in one-stage. Methods Between March 2007 and September 2009, 8 cases of thoracic vertebra tuberculosis were treated. Of 8 cases, 6 were male and 2 were female, aged 32 years on average (range, 20-42 years). The disease duration ranged from 8 to 14 months (mean, 10.2 months). Affected vertebrae included thoracic vertebrae in 35 cases and lumbar vertebrae in 11 cases; 5 vertebrae were involved in 4 cases, 6 vertebrae in 3 cases, and 8 vertebrae in 1 case. According to Frankel classification, there were 2 cases of grade C, 4 cases of grade D, and 2 cases of grade E. All patients had different kyphosis with the Cobb angle of (25.1 ± 6.6)°. All patients received antituberculous therapy 4-6 weeks preoperatively; after complete clearance lesions, autograft bone fusion and internal fixation were performed, and then antituberculous therapy was given for 18 months. Results All incisions healed by first intention. Eight patients were followed up 18-48 months (mean, 29 months). According to JIN Dadi et al. criterion, 7 cases recovered after first operation, 1 case of relapsed tuberculosis with sious was cured after re-focus clearance. The Cobb angle was (19.5 ± 4.2)° at 7 days after operation and was (22.3 ± 3.6)° at last follow-up, showing significant differences when compared with the preoperative value (P lt; 0.05). The nerve function of all cases were classified as Frankel grade E. CT scan showed bone graft fusion at 6-8 months after operation. No loosening or displacement of grafted bone and internal fixation occurred during follow-up. Conclusion The treatment of adjacent multivertebral tuberculosis by anterior focus clearance, intervertebral autograft, and internal fixation in one-stage is effective. Anterior bone fusion and internal fixation in one-stage can correct kyphosis effectively and rebuild spinal stabil ity, so it is a good choice for surgical treatment of adjacent multivertebral tuberculosis.
Objective To review the current development of the dynamic stabilization devices and their biomechanics as well as clinical application.Methods The related biomedical research papers at home and abroad were consulted and analyzed Results There were obvious advances in the theoretic foundation and the clinical application in treatment of the degenerative lumbar disorders with the dynamic stabilization devices, especially with the nonfusion dynamic stabilization devices. Conclusion The effectiveness of the dynamic stabilization devices have attracted more and more biomedical researchers, especially the posterior dynamic stabilization device, which has provided a new approach to treatment of the degenerative lumbar disorders.
Objective To study the properties of the xenogeneic deproteinized cancellous bone used as a scaffold in the bone tissue engineering andits application to the spinal fusion of the lumbar intertransverse process in agoat. Methods The deproteinized bone was derived from an adult pig’s femoral cancellous bone through the physical and chemical treatments. Its morphological features, constituting components, and biomechanical properties were examined by the scanning electron microscopy, X-ray diffraction analysis, and mechanical experimental instrument. The cell-material complex was observed under the inverted phase contrast microscope to evaluate the adhesion and the growth of the osteoblasts. The experimental model of the spinal fusion of the lumbar intertransverse process was produced in 12 male goats aged 6-8 months, which were divided into two groups. In Group A, the tissue engineered bone constructed by thexenogeneic deproteinized cancellous bone, the recombinant human bone morphogenetic protein 2, and the mesenchymal stem cells was used for the spinal fusion; however, in Group B the autoilium was used. The samples were harvested at 4, 8 and 12 weeks postoperatively, and a series of examinations were performed, including the radiography and the histomorphological assay. Results The deproteinized cancellous bone had a natural pore network system, with an aperture ranging in size from 200 to 500 μm, containing a main organic material ofcollagen and the inorganic material of hydroxyapatite. So, the deproteinized cancellous bone had a good mechanical strength and a good histocompatibility. In Group A, the X-ray examination at different timepoints postoperatively showed that at 4 weeks,the bridging areas of all the fusion sites were not clear, especially on the internal side; at 8 weeks, the upper and lower bridged parts had a narrowed gap, with formation of much continuous bony callus; at 12 weeks, a complete fusion occurred. In the early stage, the material density was slightly lowerin Group A than in Group B, but at 12 weeks the density was almost the same in both the groups. Histological examination in the transplant area showed that at 4 weeks in Group A there was a new bone formation in a multipoint way; at 8 weeks, a “sandwichshaped” new bone wascrossed with the transplanting materials; and at 12 weeks, a medullary cavity was remodeled and a new cancellous bone was formed. The osteogenic process of thetissue engineered bone constructed by the xenogeneic deproteinized cancellous bone scaffold was almost the same as the autoilium osteogenesis. Conclusion The xenogeneic deproteinized cancellous bone is a good material in the bone tissue engineering, which can be used as an osteogenesis scaffold andprovide a stable environment for revascularization and osteoblastic differentiation.
ObjectiveTo explore the effectiveness of nano-hydroxyapatite/polyamide-66 (n-HA/PA66) Cage in interbody fusion for degenerative lumbar scoliosis.MethodsA retrospective analysis was designed and conducted for 43 patients, who underwent posterior decompression and n-HA/PA66 Cage interbody fusion with correction of deformity between January 2013 and June 2016. Eighteen cases were single-level fusion (single-level group) and 25 cases were double-level fusion (double-level group). There was no significant difference in gender, age, body mass index, direction of convex, degree of apical rotation, fusion level, the number of osteoporotic patients, pre-operative intervertebral height of fusion segments, coronal Cobb angle, visual analogue score (VAS), and modified Oswestry Disability Index (ODI) between 2 groups (P>0.05). The operation time, intraoperative blood loss, postoperative drainage, hospital stay, and complications of the operation were recorded. Modified ODI, VAS score, and MacNab criteria were adopted to assess clinical outcomes. Radiographic indexes, including intervertebral height of fusion segments, coronal Cobb angle, disc insertion depth, and the bone graft fusion rate, were also evaluated.ResultsThere was no significant difference in operation time, intraoperative blood loss, postoperative drainage, and hospital stay between 2 groups (P>0.05). All patients were followed up 18-62 months (mean, 30.9 months). Wound complications, postoperative delirium, and Cage retropulsion occurred in 4 cases (2 cases in single-level group, 2 cases in double-level group), 1 case of single-level group, and 1 case of double-level group, respectively. The intervertebral height of fusion segments after operation significantly improved compared with preoperative ones in both groups (P<0.05). At last follow-up, the intervertebral height in double-level group was superior to which in single-level group (P<0.05). The coronal Cobb angles after operation significantly improved compared with preoperative ones (P<0.05), and no significant difference was found between 2 groups at each time point (P>0.05). The disc insertion depth showed no significant difference between different time points after operation in 2 groups (P>0.05) and between 2 groups at each time point after operation (P>0.05). Bony fusion was obtained in all patients at last follow-up. The VAS score and modified ODI after operation in both groups were superior to those before operation (P<0.05). The VAS score in double-level group was higher than that in single-level group (P<0.05) at last follow-up, and no significant difference was found in VAS score and modified ODI between 2 groups at other time points (P>0.05). According to the MacNab criteria, the excellent and good rates at last follow-up were 94.4% and 84.0% in single-level group and double-level group, respectively.ConclusionThe n-HA/PA66 Cage can effectively restore and maintain the disc height of fusion segment, normal sequence, and biomechanical stability of the spine, and gain favorable effectivenss for degenerative lumbar scoliosis. And double-level fusion is superior to single-level fusion in maintaining disc height of fusion segment.
Objective To compare the clinical outcomes of posterior lumbar interbody fusion（PLIF） using simple cage alone fusion with pedicle screw fixationand autogenous bone grafting and cage fusion with pedicle screw fixation in adult spondylolisthesis. Methods From March 2003 to March 2004，Twenty-seven patients with lumbar spondylolisthesis were divided in two groups. In group A, 15 patients were treated by PLIF using simple cage alone fusion with pedicle screw fixation, including 4 males and 11 females, aging 53-68 years. Isthmic defectswere located at L4 in 9 cases, at L5 in 6 cases. Four patients were smokers.Thepreoperative mean disc space height was 5.4±2.3 mm, the mean percentage of slip was 36.8％±7.2%. In group B, 12 patients were treated by PLIF using autogenous bone grafting and cage fusion with pedicle screw fixation, including 3 males and 9 females, aging 56 years. Isthmic defects were located at L4 in 8 cases, atL5 in 4 cases. Five patients were smokers. The preoperative mean disc space height was 5.7±2.5 mm, the mean percentage of slip was 37.8%±6.2%. Two groupswere compared in the amount of blood loss, duration of hospitalization, back pain, radiating pain, fusion rate, the intervertebral disc space height, the postoperative degree of slip and the fusion rate. Results All patientswere followed up for 24-38 months. The mean follow-up was 29(24-36) months in group A and26(24-38) months in group B. There were no statistically significant differences infollow-up period, age,sex, the location of isthmic defects, smoking, the preoperative disc space height and the percentage of slip between two groups (Pgt;0.05).There were no statistically significant differences in the amount of blood loss, the duration of hospitalization, the fusion time between two groups(Pgt;0.05). But there were statistically significant differences in the back pain score, the radiating pain score and the fusion rate between two groups(Plt;0.05).Thepo stoperative disc space height and the degree of slip of the last follow-up were5.8±2.2 mm and 25.6％±7.2% in group A, 6.2±2.5 mm and 24.1％±7.4 % ingroupB, showing statistically significant difference (Plt;0.05). Conclusion The PLIF using autogenous bone grafting and cage fusion with pedicle screw fixations ismore beneficial to improving the fusion rate and preventing longterm instabilities than simple cage alone fusion with pedicle screw fixation in adult spondylolisthesis.