Feasibility of a novel type of complex anterior cervical fixation by using Mimics software / 中国骨伤

OBJECTIVE@#To investigate the feasibility of mimics software in analyzing a new type of complex anterior cervical fixation -- anterior transpedicular screw fixation+zero notch internal fixation.@*METHODS@#From January 2021 to September 2022, 50 normal pedestrians who underwent cervical spine CT scanning were selected for C1-C7 segment scanning, including 27 males and 23 females, aged from 25 to 65 years old with an average of (46.0 ± 9.0) years old. The dicom format is exported and engraved into the CD, and use the mimics software to perform 3D reconstruction of each segment. A simulated screw is placed on the image according to the critical value of zero notch screw (head and tail angle 44°, internal angle 29°). The position of zero notch screw in each segment is observed to determine the feasibility of anterior transpedicular screw fixation plus zero notch internal fixation.@*RESULTS@#For the upper zero notch screws the three-dimensional images of the cervical spine across all 50 subjects within the C3-C7 segments demonstrated safe position, with no instances of intersection with ATPS. For the lower zero notch screw, in C3-C4 and C4-C5, 4 out of 50 subjects are in the safe position in the three-dimensional images of cervical vertebrae, and 46 cases could achieve secure screw placement when the maximum caudal angle is(32.3±1.9) ° and (36.1±2.2) °, respectively. In C5-C6 and C6-C7 segments, no lower zero notch screws intersected with ATPS, and all screws are in safe positions.@*CONCLUSION@#Lower cervical anterior pedicle screw fixation plus zero notch internal fixation can achieve successful nail placement through the selected entry point and position.

Radicular symptoms associated with extrapedicular screw placement / Sintomas radiculares associados com a colocação extrapedicular de parafusos / Síntomas radiculares asociados a la colocación de tornillos extrapediculares

ABSTRACT: Objective: Transpedicular fixation has rapidly evolved over the last 100 years. A common complication is screw misplacement which can lead to neurological deficits, vascular damage, or organ perforation. We intend to assess the correlation between screw misplacement and radicular symptoms through the Gertzbein scale. Methods: We conducted an observational longitudinal retrospective study on patients who underwent free-hand lumbar instrumentation surgery with fluoroscopy assistance. The patients were evaluated with postoperative CT scans, and screw positions were classified with the Gertzbein scale. Results: The initial sample included 99 patients who underwent surgery. Of the 317 screws placed, 201 did not show cortical damage, 105 screws exhibited variable invasion, and 11 screws displayed severe invasion. 96.5% screws were placed in the safe zone, with 8.6% of patients (n=5.0) exhibiting transitory weakness. 3.47% of screws (n=11) with severe invasion were seen in 7 patients of which two patients suffered from motor deficient and persistent radicular pain. Conclusion: It is of the utmost importance to pay attention to the precise insertion of the screws to minimize the risk of radicular manifestations. We recommend performing control CT scans after the procedure to ensure the correct insertion of the screws, and in case of finding a screw in a no-safe zone or Getsbein 3 position, considering screw repositioning due to high-risk neurologic damage is highly encouraged. Level of Evidence II; Observational Retrospective Study.

RESUMO: Objetivo: A fixação transpedicular evoluiu rapidamente nos últimos 100 anos, porém o deslocamento do parafuso é uma complicação comum que pode resultar em déficits neurológicos ou danos vasculares. Pretendemos correlacionar o deslocamento do parafuso com sintomas radiculares usando a escala de Gertzbein. Métodos: Conduzimos um estudo retrospectivo longitudinal observacional em pacientes submetidos à cirurgia de instrumentação lombar à mão livre com assistência de fluoroscopia. Os pacientes foram avaliados com tomografia computadorizada pós-operatória e as posições dos parafusos foram classificadas com a escala de Gertzbein. Resultados: A amostra inicial incluiu 99 pacientes. Dos 317 parafusos colocados, 201 não mostraram danos corticais, 105 exibiram invasão variável e 11 invasão severa. 96,5% dos parafusos foram colocados na zona segura, com 8,6% dos pacientes apresentando fraqueza transitório. 3,47% dos parafusos com invasão severa foram observados em 7 pacientes, dos quais 2 sofreram de deficiência motora e dor radicular persistente. Conclusão: É crucial prestar atenção à inserção precisa dos parafusos para minimizar o risco de manifestações radiculares. Recomendamos tomografias de controle para garantir a correta inserção dos parafusos e, se necessário, reposicionamento devido ao alto risco de dano neurológico. Nível de Evidência II; Estudo Observacional Retrospectivo.

RESUMEN: Objetivo: La fijación transpedicular ha evolucionado en los últimos 100 años. Una complicación común es el desplazamiento de tornillos, causante de déficits neurológicos o daños vasculares. Buscamos correlacionar el desplazamiento con síntomas radiculares mediante la escala de Gertzbein. Métodos: Se realizó un estudio observacional longitudinal retrospectivo de pacientes sometidos a cirugía de instrumentación lumbar a mano alzada asistida por fluoroscopia. Los pacientes fueron evaluados con tomografía computarizada postoperatoria y las posiciones de los tornillos se clasificaron con la escala de Gertzbein. Resultados: La muestra inicial incluyó 99 pacientes. De los 317 tornillos colocados, 201 no mostraron daño cortical, 105 mostraron invasión variable y 11 mostraron invasión severa. El 96,5% de los tornillos se colocaron en la zona segura, y el 8,6% de los pacientes mostraron debilidad transitoria. Se observó un 3,47% de tornillos con invasión grave en 7 pacientes, 2 de los cuales sufrieron discapacidad motora y dolor radicular persistente. Conclusión: Es crucial prestar atención a la inserción precisa de los tornillos para minimizar el riesgo de manifestaciones radiculares. Recomendamos la realización de tomografias de control para asegurar la correcta inserción de los tornillos y, en caso necesario, su recolocación debido al elevado riesgo de daño neurológico. Nivel de Evidencia II; Estudio Observacional Retrospectivo.

Lumbar arthrodesis in lateral single position: concepts, rational and clinical-functional results of 100 consecutive cases / Artrodese lombar em decúbito lateral único: conceitos, justificativas e resultados clínico-funcionais de 100 casos consecutivos / Artrodesis lumbar en posición lateral única: conceptos, justificaciones y resultados clínico-funcionales de 100 casos consecutivos

ABSTRACT Objective: Arthrodesis techniques such as anterior lumbar interbody fusion (ALIF) and lateral lumbar interbody fusion (LLIF) aim to reestablish physiological lordosis and minimize tissue damage to the paravertebral musculature. Supplementation with percutaneous pedicle screws is indicated in most cases, therefore, intraoperative changes in decubitus are necessary, generating costs and risks for the patient. This study aims to present concepts and results of a series of 100 cases of patients undergoing 360° fusion in lateral single position surgery (LSPS). Methods: retrospective analysis of databases collected between 2016 and 2021. Patients who underwent 360° fusion of the lumbar spine in single lateral decubitus to treat degenerative and infectious diseases were included. Cases with arthrodesis greater than 3 levels were excluded. Data collected include demographics, body mass index (BMI) and scores such as visual analog scale (VAS), EuroQOL 5D (EQ5D) and Oswestry disability index (ODI). Results: 100 patients were included in the study, submitted to LLIF and/or ALIF associated with percutaneous pedicle fixation. The lumbar VAS improved from 6.75 to 2.1 after 12 months, while the sciatica VAS started from 4.55 and reached 0.81 after one year. The EQ5D improved from 66.1 to 81.6 after the first year, while the ODI ranged from 28.54 to 14.18 in the same period. Conclusions: the clinical-functional results of the LSPS procedures are favorable and place the LSPS as an option to be studied, developed and practiced by spine surgery teams. Level of evidence: IV. Case series.

Resumo: Objetivo: Técnicas de artrodese como anterior lumbar interbody fusion (ALIF) e lateral lumbar interbody fusion (LLIF) tem como objetivos o reestabelecimento da lordose fisiológica e a mínima lesão tecidual da musculatura paravertebral. A suplementação com parafusos pediculares por via percutânea é indicada na maioria dos casos, sendo, portanto, necessárias mudanças de decúbito intraoperatórias, gerando custos e riscos para o paciente. Este estudo tem como objetivo apresentar conceitos e resultados de uma série de 100 casos de pacientes submetidos a fusão 360° em lateral single position surgery (LSPS). Métodos: análise retrospectiva de banco de dados coletados entre 2016 e 2021. Foram incluídos pacientes submetidos a fusão 360° da coluna lombar em decúbito lateral único para tratamento doenças degenerativas e infecciosas. Foram excluídos casos com artrodeses maiores que 3 níveis. Os dados coletados incluem demografia, índice de massa corpórea (IMC) e scores como visual analog scale (VAS), EuroQOL 5D (EQ5D) e Oswestry disability index (ODI). Resultados: 100 pacientes foram incluídos no estudo, submetidos a LLIF e/ ou ALIF associados a fixação pedicular percutânea. O VAS lombar apresentou melhora de 6,75 para 2,1 após 12 meses, já o VAS ciatalgia partiu de 4,55 e atingiu 0,81 após um ano. O EQ5D apresentou melhora de 66,1 para 81,6 após o primeiro ano, enquanto o ODI variou de 28,54 para 14,18 no mesmo período. Conclusões: os resultados clínico-funcionais dos procedimentos em LSPS se mostram favoráveis e a colocam o LSPS como uma opção a ser estudada, desenvolvida e praticada pelas equipes de cirurgia de coluna. Nível de evidência: IV. Série de casos.

Resumen: Objetivo: Las técnicas de artrodesis como la fusión intersomática lumbar anterior (ALIF) y la fusión intersomática lumbar lateral (LLIF) tienen como objetivo restablecer la lordosis fisiológica. La suplementación con tornillos pediculares percutáneos está indicada en la mayoría de los casos, por lo que son necesarios cambios en decúbito intraoperatorios, generando costos y riesgos para el paciente. Este estudio tiene como objetivo presentar conceptos y resultados de una serie de 100 casos de pacientes sometidos a fusión de 360° en cirugía de posición única lateral (LSPS). Métodos: análisis retrospectivo de bases de datos recolectadas entre 2016 y 2021. Se incluyeron pacientes que se sometieron a fusión de columna lumbar 360° en decúbito lateral y se excluyeron los casos con artrodesis mayores de 3 niveles. Los datos recopilados incluyen datos demográficos, índice de masa corporal (IMC) y puntajes como la escala analógica visual (VAS), EuroQOL 5D (EQ5D) y el índice de discapacidad de Oswestry (ODI). Resultados: 100 pacientes fueron incluidos en el estudio, sometidos a LLIF y/o ALIF asociados a fijación pedicular percutánea. La EVA lumbar mejoró de 6,75 a 2,1 a los 12 meses, mientras que la EVA de ciática partió de 4,55 y llegó a 0,81 al año. El EQ5D mejoró 66,1 a 81,6 después del primer año, mientras que el ODI varió 28,54 a 14,18 en el mismo período. Conclusiones: los resultados clínico-funcionales de los procedimientos de LSPS son favorables y a sitúan como una opción a ser estudiada, desarrollada y practicada por los equipos de cirugía de columna. Nivel de evidencia: IV. Series de casos.

Application of a new point contact pedicle navigation template as an auxiliary screw implant in scoliosis correction surgery / 中国修复重建外科杂志

OBJECTIVE@#To explore the effectiveness of a new point contact pedicle navigation template (referred to as "new navigation template" for simplicity) in assisting screw implantation in scoliosis correction surgery.@*METHODS@#Twenty-five patients with scoliosis, who met the selection criteria between February 2020 and February 2023, were selected as the trial group. During the scoliosis correction surgery, the three-dimensional printed new navigation template was used to assist in screw implantation. Fifty patients who had undergone screw implantation with traditional free-hand implantation technique between February 2019 and February 2023 were matched according to the inclusion and exclusion criteria as the control group. There was no significant difference between the two groups ( P>0.05) in terms of gender, age, disease duration, Cobb angle on the coronal plane of the main curve, Cobb angle at the Bending position of the main curve, the position of the apical vertebrae of the main curve, and the number of vertebrae with the pedicle diameter lower than 50%/75% of the national average, and the number of patients whose apical vertebrae rotation exceeded 40°. The number of fused vertebrae, the number of pedicle screws, the time of pedicle screw implantation, implant bleeding, fluoroscopy frequency, and manual diversion frequency were compared between the two groups. The occurrence of implant complications was observed. Based on the X-ray films at 2 weeks after operation, the pedicle screw grading was recorded, the accuracy of the implant and the main curvature correction rate were calculated.@*RESULTS@#Both groups successfully completed the surgeries. Among them, the trial group implanted 267 screws and fused 177 vertebrae; the control group implanted 523 screws and fused 358 vertebrae. There was no significant difference between the two groups ( P>0.05) in terms of the number of fused vertebrae, the number of pedicle screws, the pedicle screw grading and accuracy, and the main curvature correction rate. However, the time of pedicle screw implantation, implant bleeding, fluoroscopy frequency, and manual diversion frequency were significantly lower in trial group than in control group ( P<0.05). There was no complications related to screws implantation during or after operation in the two groups.@*CONCLUSION@#The new navigation template is suitable for all kinds of deformed vertebral lamina and articular process, which not only improves the accuracy of screw implantation, but also reduces the difficulty of operation, shortens the operation time, and reduces intraoperative bleeding.

Effectiveness of sagittal top compression reduction technique in treatment of thoracolumbar vertebral fractures / 中国修复重建外科杂志

OBJECTIVE@#To investigate the effectiveness of sagittal top compression reduction technique in the treatment of thoracolumbar vertebral fractures.@*METHODS@#A retrospective analysis was conducted on the clinical data of 59 patients with thoracolumbar vertebral fractures who met the selection criteria and were admitted between November 2018 and January 2022. Among them, 34 patients were treated with sagittal top compression reduction technique (top pressure group), and 25 patients were treated with traditional reduction technique (traditional group). There was no significant difference in baseline data between the two groups ( P>0.05), including gender, age, fracture segment, cause of injury, AO classification of thoracolumbar vertebral fractures, thoracolumbar injury classification and severity (TLICS) score, American Spinal Injury Association (ASIA) grading, surgical approach, preoperative vertebral body index, height ratio of the anterior margin of injured vertebra, injured vertebra angle, segmental kyphosis angle, visual analogue scale (VAS) score, and Oswestry disability index (ODI). The operation time, intraoperative blood loss, and incidence of complications between the two groups were recorded and compared. After operation, VAS score and ODI were used to evaluate effectiveness, and X-ray and CT examinations were performed to measure imaging indicators such as vertebral body index, height ratio of the anterior margin of injured vertebra, injured vertebra angle, and segmental kyphosis angle.@*RESULTS@#There was no significant difference in operation time and intraoperative blood loss between the two groups ( P>0.05). No complication such as dural sac, nerve root, or vascular injury was found during operation, and all incisions healed by first intention. Patients in both groups were followed up 6-48 months, with an average of 20.6 months. No loosening, breakage, or failure of internal fixation occurred during follow-up. The imaging indicators, VAS score, and ODI of the two groups significantly improved at 1 week and last follow-up when compared to preoperative ones ( P<0.05). At last follow-up, the VAS score and ODI further significantly improved when compared to 1 week after operation ( P<0.05). At 1 week after operation and last follow-up, the vertebral body index, segmental kyphosis angle, injured vertebra angle, and ODI in the top pressure group were significantly better than those in the traditional group ( P<0.05). There was no significant difference in VAS score and height ratio of the anterior margin of injured vertebra between the two groups at 1 week after operation ( P>0.05), but the two indicators in the top pressure group were significantly better than those in the traditional group at last follow-up ( P<0.05).@*CONCLUSION@#The treatment of thoracolumbar vertebral fractures with sagittal top compression reduction technique can significantly improve the quality of vertebral reduction, and is superior to traditional reduction techniques in relieving pain and improving spinal function.

Clinical application of percutaneous pedicle screw placement guided by ultrasound volume navigation combined with X-ray fluoroscopy: a prospective randomized controlled study / 中国修复重建外科杂志

OBJECTIVE@#To explore the feasibility and accuracy of ultrasound volume navigation (UVN) combined with X-ray fluoroscopy-guided percutaneous pedicle screw implantation through a prospective randomized controlled study.@*METHODS@#Patients with thoracic and lumbar vertebral fractures scheduled for percutaneous pedicle screw fixation between January 2022 and January 2023 were enrolled. Among them, 60 patients met the selection criteria and were included in the study. There were 28 males and 32 females, with an average age of 49.5 years (range, 29-60 years). The cause of injury included 20 cases of traffic accidents, 21 cases of falls, 17 cases of slips, and 2 cases of heavy object impact. The interval from injury to hospital admission ranged from 1 to 5 days (mean, 1.57 days). The fracture located at T 12 in 15 cases, L 1 in 20 cases, L 2 in 19 cases, and L 3 in 6 cases. The study used each patient as their own control, randomly guiding pedicle screw implantation using UVN combined with X-ray fluoroscopy on one side of the vertebral body and the adjacent segment (trial group), while the other side was implanted under X-ray fluoroscopy (control group). A total of 4 screws and 2 rods were implanted in each patient. The implantation time and fluoroscopy frequency during implantation of each screw, angle deviation and distance deviation between actual and preoperative planned trajectory by imaging examination, and the occurrence of zygapophysial joint invasion were recorded.@*RESULTS@#In terms of screw implantation time, fluoroscopy frequency, angle deviation, distance deviation, and incidence of zygapophysial joint invasion, the trial group showed superior results compared to the control group, and the differences were significant ( P<0.05).@*CONCLUSION@#UVN combined with X-ray fluoroscopy-guided percutaneous pedicle screw implantation can yreduce screw implantation time, adjust dynamically, reduce operational difficulty, and reduce radiation damage.

Comparison of screw placement guided by O-arm navigation and ultrasound volume navigation in minimally invasive transforaminal lumbar interbody fusion / 中国修复重建外科杂志

OBJECTIVE@#To compare the effectiveness of O-arm navigation and ultrasound volume navigation (UVN) in guiding screw placement during minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) surgery.@*METHODS@#Sixty patients who underwent MIS-TLIF surgery for lumbar disc herniation between June 2022 and June 2023 and met the selection criteria were included in the study. They were randomly assigned to group A (screw placement guided by UVN during MIS-TLIF) or group B (screw placement guided by O-arm navigation during MIS-TLIF), with 30 cases in each group. There was no significant difference in baseline data, including gender, age, body mass index, and surgical segment, between the two groups ( P>0.05). Intraoperative data, including average single screw placement time, total radiation dose, and average single screw effective radiation dose, were recorded and calculated. Postoperatively, X-ray film and CT scans were performed at 10 days to evaluate screw placement accuracy and assess facet joint violation. Pearson correlation and Spearman correlation analyses were used to observe the relationship between the studied parameters (average single screw placement time and screw placement accuracy grading) and BMI.@*RESULTS@#The average single screw placement time in group B was significantly shorter than that in group A, and the total radiation dose of single segment and multi-segment and the average single screw effective radiation dose in group B were significantly higher than those in group A ( P<0.05). There was no significant difference in the total radiation dose between single segment and multiple segments in group B ( P>0.05), while the total radiation dose of multiple segments was significantly higher than that of single segment in group A ( P<0.05). No significant difference was found in the accuracy of screw implantation between the two groups ( P>0.05). In both groups, the grade 1 and grade 2 screws broke through the outer wall of the pedicle, and no screw broke through the inner wall of the pedicle. There was no significant difference in the rate of facet joint violation between the two groups ( P>0.05). In group A, both the average single screw placement time and screw placement accuracy grading were positively correlated with BMI ( r=0.677, P<0.001; r=0.222, P=0.012), while in group B, neither of them was correlated with BMI ( r=0.224, P=0.233; r=0.034, P=0.697).@*CONCLUSION@#UVN-guided screw placement in MIS-TLIF surgery demonstrates comparable efficiency, visualization, and accuracy to O-arm navigation, while significantly reducing radiation exposure. However, it may be influenced by factors such as obesity, which poses certain limitations.

Effectiveness of one-stage posterior eggshell osteotomy and long-segment pedicle screw fixation for ankylosing spondylitis kyphosis combined with acute thoracolumbar vertebral fracture / 中国修复重建外科杂志

OBJECTIVE@#To explore the safety and effectiveness of one-stage posterior eggshell osteotomy and long-segment pedicle screw fixation in the treatment of ankylosing spondylitis kyphosis combined with acute thoracolumbar vertebral fracture.@*METHODS@#A clinical data of 20 patients with ankylosing spondylitis kyphosis combined with acute thoracolumbar spine fracture, who were treated with one-stage posterior eggshell osteotomy and long-segment pedicle screw fixation between April 2016 and January 2022, was retrospectively analyzed. Among them, 16 cases were male and 4 cases were female; their ages ranged from 32 to 68 years, with an average of 45.9 years. The causes of injury included 10 cases of sprain, 8 cases of fall, and 2 cases of falling from height. The time from injury to operation ranged from 1 to 12 days, with an average of 7.1 days. The injured segment was T 11 in 2 cases, T 12 in 2 cases, L 1 in 6 cases, and L 2 in 10 cases. X-ray film and CT showed that the patients had characteristic imaging manifestations of ankylosing spondylitis, and the fracture lines were involved in the anterior, middle, and posterior columns and accompanied by different degrees of kyphosis and vertebral compression; and MRI showed that 12 patients had different degrees of nerve injuries. The operation time, intraoperative bleeding, intra- and post-operative complications were recorded. The visual analogue scale (VAS) score and Oswestry disability index (ODI) were used to evaluate the low back pain and quality of life, and the American spinal cord injury association (ASIA) classification was used to evaluate the neurological function. X-ray films were taken, and local Cobb angle (LCA) and sagittal vertical axis (SVA) were measured to evaluate the correction of the kyphosis.@*RESULTS@#All operations were successfully completed and the operation time ranged from 127 to 254 minutes (mean, 176.3 minutes). The amount of intraoperative bleeding ranged from 400 to 950 mL (mean, 722.5 mL). One case of dural sac tear occurred during operation, and no cerebrospinal fluid leakage occurred after repair, and the rest of the patients did not suffer from neurological and vascular injuries, cerebrospinal fluid leakage, and other related complications during operation. All incisions healed by first intention without infection or fat liquefaction. All patients were followed up 8-16 months (mean, 12.5 months). The VAS score, ODI, LCA, and SVA at 3 days after operation and last follow-up significantly improved when compared with those before operation ( P<0.05), and the difference between 3 days after operation and last follow-up was not significant ( P>0.05). The ASIA grading of neurological function at last follow-up also significantly improved when compared with that before operation ( P<0.05), including 17 cases of grade E and 3 cases of grade D. At last follow-up, all bone grafts achieved bone fusion, and no complications such as loosening, breaking of internal fixation, and pseudoarthrosis occurred.@*CONCLUSION@#One-stage posterior eggshell osteotomy and long-segment pedicle screw fixation is an effective surgical procedure for ankylosing spondylitis kyphosis combined with acute thoracolumbar vertebral fracture. It can significantly relieve patients' clinical symptoms and to some extent, alleviate the local kyphotic deformity.

Analysis of the clinical effect of percutaneous pedicle screw fixation combined with transpedicular bone grafting in the treatment of thoracolumbar fracture / 中国骨伤

OBJECTIVE@#To investigate the clinical efficacy of percutaneous screw fixation combined with minimally invasive transpedicular bone grafting and non-bone grafting in the treatment of thoracolumbar fractures.@*METHODS@#From Janury 2021 to June 2022, 40 patients with thoracolumbar fracture were divided into the experimental group and the control group. There were 26 patients in the experimental group, including 21 males and 5 females with an aberage age of (47.3±12.3) years old, who underwent percutaneous pedicle screw fixation combined with transpedicular autogenous bone grafting. In the control group, 14 patients received percutaneous pedicle screw fixation only. including 7 makes and 7 females with an average age of (50.2±11.2) years old. The operative time, intraoperative blood loss, anterior height ratio of injured vertebrae, Cobb angle, visual analogue score (VAS), MacNab scores, loosening or broken of the implants. were compared and analyzed.@*RESULTS@#There was no significant difference in operation time, intraoperative blood loss, VAS and anterior height ratio of injured vertebrae between the two groups. Compared with the preoperative results, VAS and anterior height ratio of injured vertebrae were improved statistically(P<0.05). For Cobb angle of injured vertebra, there was no significant difference between the two groups before surgery (P=0.766). While at 1 week, 3 months and 12 months after surgery, there were statistically differences between the two groups (P values were 0.042, 0.007 and 0.039, respectively). The Cobb angle of injured vertebrae one year after operation was statistically decreased in both groups compared with that before surgery (P<0.001). One year after surgery, the excellent and good rate of Macnab scores was 96.15% in the experimental group and 92.86% in the control group, and there was no statistical differences between the two groups (P=0.648). There was one patient in the control group suffering superficial wound infection on the third day, which was cured by dressing change and anti-infection treatment. There were no postoperative screw loosening and broken in both groups.@*CONCLUSION@#The two surgical methods have the advantages of less trauma, less pain and quicker recovery, which can restore the height of the injured vertebra, reconstruct the spinal sequence and reduce the fracture of the vertebral body. Transpedicular autogenous bone grafting can increase the stability of the fractured vertebra and maintain the height of the vertebra better after surgery, thus reducing the possibility of complications such as kyphosis, screw loosening and broken.

Treatment of spinal burst fractures with pedicle screw fixation at high altitude area / 中国骨伤

OBJECTIVE@#According to the characteristics of spinal burst fractures in high-altitude areas and the local medical conditions, to explore the clinical efficacy of short-segment fixation with pedicle screws combined with screw placement in injured vertebrae in the treatment of thoracolumbar burst fractures.@*METHODS@#From August 2018 to December 2021, 12 patients with single-vertebral thoracolumbar burst fractures without neurological symptoms were treated with injured vertebral screw placement technique, including 7 males and 5 females;aged 29 to 54 years old, with an average of(42.50±7.95) years old;6 cases of traffic accident injury, 4 cases of high fall injury, 2 cases of heavy object injury;2 cases of T11, 4 cases of T12, 3 cases of L1, 2 cases of L2, and 1 case of L3. In the operation, screws were first placed in the upper and lower vertebrae of the fracture, pedicle screws were placed in the injured vertebra, and connecting rods were installed, and the fractured vertebral body was reset by positioning and distraction. Visual analogue scale (VAS) and Japanese Orthopedic Association (JOA) scoring were used to evaluate the changes in pain and quality of life of patients, and the kyphotic correction rate and correction loss rate of the injured segment were measured by X-ray.@*RESULTS@#All operations were successful without significant intraoperative complications. All 12 patients were followed up, the duration ranged from 9 to 27 months, with an mean of (17.75±5.79) months. VAS at 3 days after operation was significantly higher than that at admission (t=6.701, P=0.000). There was significant difference in JOA score between 9 months after operation and at admission (t=5.085, P=0.000). Three days after operation, Cobb angle was (4.42±1.16)°, and the correction rate was (82±5)% compared with (25.67±5.71)° at admission. Cobb angle was (5.08±1.24) °at 9 months after operation, with a corrected loss rate of (16±13)%. No loosening or breakage of internal fixation was found.@*CONCLUSION@#Under the high-altitude hypobaric and hypoxic environment, the effect of the operation should be ensured while reducing the trauma. The application of the technique of placing screws on the injured vertebra can effectively restore and maintain the height of the injured vertebra, with less bleeding and shorter fixed segments, which is an effective method.

Percutaneous pedicle screw fixation combined expandable tubular retractor in the treatment of spinal metastases / 北京大学学报(医学版)

OBJECTIVE@#To investigate the effectiveness of percutaneous pedicle screw fixation combined expandable tubular retractor in the treatment of patients with spinal metastases.@*METHODS@#In the study, 12 patients of spinal metastases treated with percutaneous pedicle screw fixation combined expandable tubular retractor in our hospital were retrospectively reviewed between June 2017 and October 2019. Among the 12 patients, 9 were males and 3 were females; the median age was 62.5 years [(65.1±2.9) years]. The decompression segment of 7 patients was located at the lower thoracic spine (including 1 patient with incomplete paraplegia) and the decompression segment of 5 patients was located at the lumbar spine; Tomita score was 6.0±0.6. Perioperative data of the patients were reviewed. Visual analog scale (VAS score), Karnofsky score, and Eastern Cooperative Oncology Group (ECOG) score were compared before and after surgery. The patient's survival, adjuvant treatment, and internal fixation failure were observed in the follow-up period.@*RESULTS@#All the 12 patients had a successful operation with percuta-neous pedicle screw fixation combined expandable tubular retractor. The average operative time, blood loss, and blood transfused of the patients were (247.0±14.6) min, (804.2±222.3) mL and (500.0±100.0) mL, respectively. The average amount of drainage was (240.8±79.3) mL. Drainage tubes were pulled out early postoperative [(3.2±0.3) d], allowing early mobilization. The patients discharged (7.8±0.8) d postoperative. All the patients were followed up for 6-30 months, and the average overall survival time was (13.6±2.4) months. During the follow-up period, 2 patients experienced screw displacement, the internal fixation was stable after conservative treatment and no revision surgery was performed. The VAS of the patients was 7.1±0.2 before surgery, which decreased to 2.3±0.1 and 2.8±0.4 at 3 and 6 months after surgery (P < 0.05). The Karnofsky score of the patients was 59.2±1.9 before surgery, which increased to 75.0±1.9 and 74.2±3.1 at 3 and 6 months after surgery (P < 0.05). The ECOG of the patients was 2.3±0.2 before surgery, which decreased to 1.7±0.1 and 1.7±0.2 at 3 and 6 months after surgery (P < 0.05).@*CONCLUSION@#For selected patients with spinal metastases, minimally invasive surgical treatment of spinal metastases (percutaneous pedicle screw internal fixation combined with expandable tubular retractor) can effectively relieve the clinical symptoms and improve the quality of life, with satisfactory clinical outcome.

Treatment of stage Ⅱ-Ⅲ Kümmell disease with robot-assisted bone cement-augmented pedicle screw fixation / 中国骨伤

OBJECTIVE@#To evaluate the early clinical efficacy of robot-assisted percutaneous short-segment bone cement-augmented pedicle screw fixation in the treatment of stageⅡ-Ⅲ Kümmell disease.@*METHODS@#The clinical data of 20 patients with stageⅡ-Ⅲ Kümmell's disease who underwent robot-assisted percutaneous bone cement-augmented pedicle screw fixation between June 2017 and January 2021 were retrospectively analyzed. There were 4 males and 16 females, aged from 60 to 81 years old with an average age of (69.1±8.3) years. There were 9 cases of stageⅡand 11 cases of stage Ⅲ, all of which were single vertebral lesions, including 3 cases of T11, 5 cases of T12, 8 cases of L1, 3 cases of L2, and 1 case of L3. These patients did not exhibit symptoms of spinal cord injury. The operation time, intraoperative blood loss, and complications were recorded. The position of pedicle screws and the filling and leakage of bone cement in gaps were observed using postoperative CT 2D reconstruction. The data of the visual analogue scale (VAS), Oswestry disability index (ODI), kyphosis Cobb angle, wedge angle of the diseased vertebra, and anterior and posterior vertebral height on lateral radiographs were statistically analyzed preoperatively, 1 week postoperatively, and at the final follow-up.@*RESULTS@#Twenty patients were followed up for 10 to 26 months, with an average follow-up of (16.0±5.1) months. All operations were successfully completed. The surgical duration ranged from 98 to 160 minutes, with an average of (122±24) minutes. The intraoperative blood loss ranged from 25 to 95 ml, with an average of (45±20) ml. There were no intraoperative vascular nerve injuries. A total of 120 screws were inserted in this group, including 111 screws at grade A and 9 screws at grade B according to the Gertzbein and Robbins scales. Postoperative CT indicated that the bone cement was well-filled in the diseased vertebra, and cement leakage occurred in 4 cases. Preoperative VAS and ODI were (6.05±0.18) points and (71.10±5.37)%, respectively, (2.05±0.14) points and (18.57±2.77)% at 1 week after operation, and (1.35±0.11) points and (15.71±2.12) % at final follow-up. There were significant differences between postoperative 1 week and preoperative, and between final follow-up and postoperative 1 week(P<0.01). Anterior and posterior vertebral height, kyphosis Cobb angle, and wedge angle of the diseased vertebra were(45.07±1.06)%, (82.02±2.11)%, (19.49±0.77) °, and (17.56±0.94) ° preoperatively, respectively, (77.00±0.99)%, (83.04±2.02)%, (7.34±0.56) °, and (6.15±0.52) ° at 1 week postoperatively, and (75.13±0.86)%, (82.39±0.45)%, (8.38±0.63) °, and (7.09±0.59) ° at the final follow-up.@*CONCLUSION@#Robot-assisted percutaneous short-segment bone cement-augmented pedicle screw fixation demonstrates satisfactory short-term efficacy in treating stageⅡ-Ⅲ Kümmell's disease as an effective minimally invasive alternative. However, longer operation times and strict patient selection criteria are necessary, and long-term follow-up is required to determine its lasting effectiveness.

O-arm real-time guidance in cervical pedicle screw fixation / 中国骨伤

OBJECTIVE@#To explore the technical aspects of the accuracy of cervical pedicle screw placement with O-arm guidance.@*METHODS@#The clinical data of 21 patients who underwent cervical pedicle screw fixation by O-arm real-time guidance from December 2015 to January 2020 were analyzed retrospectively. There were 15 males and 6 females, aged from 29 to 76 years old with an average of (45.3±11.5) years. The postoperative CT scan was utilized to evaluate the placement of the pedicle screw and classified according to the Gertzbein and Robbins classification.@*RESULTS@#A total of 132 pedicle screws were implanted in 21 patients, 116 at C3-C6 and 16 at C1 and C2. According to Gertzbein & Robbins classification, the overall breach rates were found to be 11.36% (15/132) with 73.33% (11 screws) Grade B, 26.67% (4 screws) Grade C, and no Grade D or E screw breaches. There were no pedicle screw placement related complications at final follow-up.@*CONCLUSION@#The application of O-arm real-time guidance technology can make cervical pedicle screw placement reliable. High accuracy and better intra-operative control can increase surgeon's confidence in using cervical pedicle instrumentation. Considering the high-risk nature of anatomical area around cervical pedicle and the possibility of catastrophic complications, the spine surgeon should have sufficient surgical skills, experience, ensures stringent verification of the system, and never relies solely on the navigation system.

Posterior cervical pedicle screw rod short-segment internal fixation for the treatment of atlantoaxial fracture and dislocation / 中国骨伤

OBJECTIVE@#To investigate the clinical efficacy of posterior cervical pedicle screw short-segment internal fixation for the treatment of atlantoaxial fracture and dislocation.@*METHODS@#The clinical data of 60 patients with atlantoaxial vertebral fracture and dislocation underwent surgery between January 2015 and January 2018 were retrospectively analyzed. The patients were divided into study group and control group according to different surgical methods. There were 30 patients in study group, including 13 males and 17 females, with an average age of (39.32±2.85) years old, were underwent short-segment internal fixation with posterior cervical pedicle screws. There were 30 patients in control group, including 12 males and 18 females, with an average age of (39.57±2.90) years old, were underwent posterior lamina clip internal fixation of the atlas. The operation time, intraoperative blood loss, postoperative ambulation time, hospitalization time and complications between two groups were recorded and compared. The pain visual analogue scale(VAS), Japanese Orthopedic Association(JOA) score of neurological function, and fusion status were evaluated between two groups.@*RESULTS@#All patients were followed up for at least 12 months. The study group was better than control group in operation time, intraoperative blood loss, postoperative off-bed activity time, and hospital stay (P=0.000). One case of respiratory tract injury occurred in study group. In control group, 2 cases occurred incision infection, 3 cases occurred respiratory tract injury, and 3 cases occurred adjacent segmental joint degeneration. The incidence of complications in study group was lower than that in control group (χ2=4.705, P=0.030). At 1, 3, 7 days after operation, VAS of study group was lower than that of control group(P=0.000). At 1, 3 months after operation, JOA score of study group was higher than that of control group(P=0.000). At 12 months after operation, all the patients in the study group achieved bony fusion. In control group, there were 3 cases of poor bony fusion and 3 cases of internal fixation fracture, the incidence rate was 20.00%(6/30). The difference between two groups was statistically significant (χ2=4.629, P=0.031).@*CONCLUSION@#Posterior cervical short-segment pedicle screw fixation for atlantoaxial fracture and dislocation has the advantages of less trauma, shorter operation time, fewer complications, and less pain, and can promote the recovery of nerve function as soon as possible.

Herniation of intervertebral disc into thoracolumbar fracture vertebral body leads to malunion of fracture and decrease of intervertebral space height / 中国骨伤

OBJECTIVE@#To analyze the clinical characteristics of intervertebral disc tissue injury and herniation into the vertebral body in thoracolumbar fracture on fracture healing, vertebral bone defect volume and intervertebral space height.@*METHODS@#From April 2016 to April 2020, a total of 140 patients with thoracolumbar single vertebral fracture combined with upper intervertebral disc injury treated with pedicle screw rod system reduction and internal fixation in our hospital. There were 83 males and 57 females, aged from 19 to 58 years old, with an average age of (39.33±10.26) years old. All patients were followed up regularly 6 months, 12 months and 18 months after surgery. The patients with injured intervertebral disc tissue not herniated into the fractured vertebral body were the control group, and the patients with injured intervertebral disc and herniated into the fractured vertebral body were the observation group. By detecting the thoracolumbar AP and lateral X-ray films, CT and MRI of the thoracolumbar segment at different follow-up time, calculate the changes of the wedge angle of the fractured vertebral body, the sagittal kyphosis angle and the height of the superior adjacent intervertebral space, the changes of the fracture healing and bone defect volume after the reduction of the vertebral body, and the changes of the intervertebral disc degeneration grade. The prognosis was evaluated by visual analogue scale(VAS) and Oswestry disability index(ODI). Finally, the differences of the above results among different groups were comprehensively analyzed.@*RESULTS@#All the patients had normal wound healing without complications. A total of 87 patients received complete follow-up data, at least 18 months after internal fixation. Thoracolumbar AP and lateral X-ray films showed that 18 months after the reduction and internal fixation operation, the vertebral wedge angle, sagittal kyphosis angle and the height of the upper adjacent intervertebral space in the observation group were greater than those in the control group(P<0.05). CT scanning showed that the deformity of the fracture healed 12 months after the vertebral body reduction in the observation group and formed a "cavity" of bone defect connected with the intervertebral space, and its volume was significantly increased compared with that before (P<0.05). MRI scanning showed that the degeneration rate of injured intervertebral discs in the observation group was more serious than that in the control group 12 months after operation(P<0.05). However, there was no significant difference in VAS and ODI score at each time.@*CONCLUSION@#Herniation of injured intervertebral disc tissue hernias into the fractured vertebral body leads to increased bone resorption defect volume around the fracture and forms a malunion "cavity" connected with the intervertebral space. This may be the main reason for the change of vertebral wedge angle, the increase of sagittal kyphosis angle and the decrease of intervertebral space height after removal of internal fixation devices.

The Influence of Thread Tap Mismatch on Pedicle Screw Pullout Strength / A influência da incompatibilidade do macho de rosca na resistência à extração do parafuso pedicular

Abstract Objective We aimed to study the "in vitro" pullout strength of SpineGuard/Zavation Dynamic Surgical Guidance Z-Direct Screw (DSG Screw, SpineGuard Inc, Boulder, Colorado, USA), a screw designed to be inserted using a direct insertion technique. Methods Dynamic Surgical Guidance Screws of 5.5 and 6.5 mm were introduced into polyurethane blocks with a density of 10 PCF (0,16g/cm3). According to the experimental group, screws were inserted without pilot hole, with pilot without tapping, undertapping and line-to-line tapping. Screw pullout tests were performed using a universal test machine after screw insertion into polyurethane blocks. Results Screws inserted directly into the polyurethane blocks without pilot hole and tapping showed a statistically higher pullout strength. Insertion of the screw without tapping or with undertapping increases the pullout screw strength compared with lineto-line tapping. Conclusion Dynamic Surgical Guidance Screw showed the highest pullout strength after its insertion without pilot hole and tapping.

Resumo Objetivo Nosso objetivo foi estudar a resistência à extração "in vitro" do parafuso SpineGuard/Zavation Dynamic Surgical Guidance Z-Direct (Parafuso DSG Guia Cirúrgico Dinâmico, SpineGuard Inc, Boulder, Colorado, USA), um parafuso projetado para ser inserido utilizando a técnica de inserção direta. Métodos Os parafusos DSG de 5,5 e 6,5 mm foram introduzidos em blocos de poliuretano com densidade de 10 PCF (0,16g/cm3). De acordo com o grupo experimental, os parafusos foram inseridos sem um orifício piloto, com um orifício piloto sem o macheamento, com macheamento e com macheamento linha a linha. Os testes de extração do parafuso foram realizados em uma máquina de teste universal, após a inserção do parafuso em blocos de poliuretano. Resultados Os parafusos inseridos diretamente nos blocos de poliuretano sem o orifício piloto e o macheamento mostraram uma resistência à extração estatisticamente maior. A inserção do parafuso sem o macheamento ou com o macho de menor diâmetro aumenta a resistência à extração do parafuso em comparação com o macheamento linha a linha. Conclusão O parafuso DSG apresentou a maior resistência à extração após a inserção sem o orifício piloto e o macheamento.

A case-control study of minimally invasive transforaminal interbody fusion with the assistance of robot and traditional fluoroscopy in the treatment of single-space lumbar disc herniation / 中国骨伤

OBJECTIVE@#To compare the safety and nail placement accuracy of fluoroscopy-assisted and robot-assisted minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) in the treatment of single-space lumbar disc herniation.@*METHODS@#The clinical data of 52 patients with single-space lumbar disc herniation treated by MIS-TLIF from March 2019 to February 2020 were retrospectively analyzed. Among them, 24 patients were treated by robot-assisted MIS-TLIF(group A) and 28 patients were treated by fluoroscopy-assisted MIS-TLIF (group B). The intraoperative blood loss, operation time, intraoperative fluoroscopy times, preoperative and postoperative visual analogue scale(VAS), Japanese Orthopaedic Association(JOA) scores and operation-related complications were recorded in two groups. Gertzbein-Robbins grade according to CT scan was used to evaluate the nail placement after operation. Grade A and B were evaluated as satisfactory nail placement, and grade C, D, and E were evaluated as error placement. Babu's method was used to evaluate the screw's invasion to the superior articular process.@*RESULTS@#The operation time, intraoperative blood loss and intraoperative fluoroscopy times in group A were less than those in group B(P<0.05).VAS and JOA scores of all patients at the final follow-up were significantly improved compared with those before operation(P<0.05), but there was no statistically significant difference between the groups(P>0.05). There were 96 and 112 screws in group A and group B, respectively. Three days after operation, according to the Gertzbein-Robbins grade to evaluate the nail placement accuracy, there were 90 screws of grade A, 5 of grade B, 1 of grade C, no grade D and E in group A;there were 84 screws of grade A, 16 of grade B, 8 of grade C, 4 of grade D, no grade E in group B;the difference between two groups was statistically significant(Z=-3.709, P=0.000). The satisfactory rate of screw placement in group A was 98.96% (95/96), and that of group B was 89.29% (100/112), the difference between two groups was statistically significant (χ2=8.254, P=0.004). Three days after operation, the invasion of superior facet joints by pedicle screws was evaluated according to Babu's method, including 90 screws in grade 0, 4 in grade 1, 2 in grade 2, and 0 in grade 3 in group A;86 in grade 0, 12 in grade 1, 10 in grade 2 and 4 in grade 3 in group B, and the difference was statistically significant(Z=-3.433, P=0.001). There were no serious spinal cord, nerve and vascular injuries and other operation-related complications caused by screw implantation failure in both groups. All patients were followed up from 6 to 12(9.06±1.60) months. The neurological symptoms improved well after operation. During the follow-up period, there was no recurrence of symptoms, loosening or breakage of the internal fixation.@*CONCLUSION@#Compared with the traditional fluoroscopy-assisted MIS-TLIF, the spinal robot-assisted MIS-TLIF not only has more minimally invasive and safer, but also has higher accuracy in nail placement, lower incidence of upper articular process invasion, and more accurate decompression targets, which can be used for minimally invasive treatment of single-space lumbar disc herniation.

Accuracy and safety of robot assisted pedicle screw placement / 中国骨伤

OBJECTIVE@#To investigate the accuracy and safety of pedicle screw placement assisted by orthopedic robot and C-arm fluoroscopy.@*METHODS@#The clinical data of 36 patients with spinal diseases underwent surgical treatment from January 2019 to August 2020 was retrospectively analyzed. Among them, 18 cases were implanted pedicle screws assisted by orthopaedic robot(observation group), including 12 males and 6 females, aged from 16 to 61 years with an average of (38.44±3.60) years;there were 1 case of adolescent scoliosis, 1 case of spinal tuberculosis, 7 cases of lumbar spondylolisthesis, 4 cases of thoracic fracture and 5 cases of lumbar fracture. Another 18 cases were implanted pedicle screws assisted by C-arm fluoroscopy(control group), including 10 males and 8 females, aged from 18 to 58 years with an average of (43.22±2.53) years;there were 1 case of adolescent scoliosis, 6 cases of lumbar spondylolisthesis, 6 cases of thoracic fracture and 5 cases of lumbar fracture. The intraoperative fluoroscopy times, nail placement time and postoperative complications were recorded in two groups. CT scan was performed after operation. The Gertzbein-Robbins standard was used to evaluate the accuracy of pedicle screw placement which was calculated.@*RESULTS@#The number of intraoperative fluoroscopy in observation group was(6.89±0.20) times, which was significantly higher than that in control group(14.00±0.18)times(P<0.05). The placement time of each screw in observation group was(2.56±0.12) min, which was significantly different from that in control group(4.22±0.17) min (P<0.05). One case of incision infection occurred in control group after operation, and recovered after active dressing change. During the follow-up period, no serious complications such as screw loosening and fracture occurred in two groups, and there was no significant difference in complications between two groups(P>0.05). A total of 107 screws were placed in observation group, including 101 screws in class A, 4 in class B, 2 in class C, 0 in class D and 0 in class E, the accuracy rate of pedicle screw placement=[(number of screws in class A+B) / the number of all screws placed in the group] ×100%=98.1%(105/107); and a total of 104 screws were placed in control group, including 90 screws in class A, 4 in class B, 5 in class C, 5 in class D and 0 in class E, the accuracy rate of pedicle screw implantation=[(number of screws in class A+B/the number of all screws placed in the group]×100%=90.3% (94/104); there was significant difference between two groups (P<0.05).@*CONCLUSION@#Orthopaedic robot assisted pedicle screw placement has the advantages of less fluoroscopy times, shorter screw placement time and higher accuracy, which can further improve the surgical safety and has a broad application prospect in the orthopaedic.

Treatment of ankylosing spondylitis with thoracolumbar fractures by robot-assisted internal fixation in lateral decubitus position / 中国骨伤

OBJECTIVE@#To explore the effect of robot-assisted internal fixation in lateral decubitus position for the treatment of ankylosing spondylitis (AS) complicated with thoracolumbar fractures.@*METHODS@#The clinical data of 26 patients with ankylosing spondylitis complicated with thoracolumbar fractures treated from January 2018 to June 2020 was retrospectively analyzed. According to different surgical methods, these patients were divided into observation group and control group. There were 8 patients in observation group, which were treated with robot-assisted percutaneous screw fixation in lateral decubitus position, including 4 males and 4 females, aged form 55 to 85 years old with an mean of (66.25±9.42) years, the course of disease was (4.00±0.76) days on average, 2 cases were T11 fracture, 2 cases were T12, 3 cases were L1 and 1 case was L2. And there were 18 patients in control group, which were treated with conventional percutaneous screw fixation in prone position, including 6 males and 12 females, aged from 48 to 81 years old with a mean of (61.22±9.53) years, the course of disease was (4.11±0.83) days on average, 2 cases were T10 injury, 3 cases were T11, 4 cases were T12, 7 cases were L1, and 2 cases were L2. The intraoperative blood loss, operation time, position time and postoperative neurological complications were compared between two groups. Postoperative visual analogue scale (VAS) at 1d and 3 months, and Oswestry Disability Index (ODI) before and 3 months after operation were observed. According to Gertzbein-Robbins standard to evaluate the accuracy of pedicle screw placement.@*RESULTS@#There was no nerve injury due to pedicle screw placement in both groups. The intraoperative blood loss in observation group and control group was (34.13±4.61) ml and (78.17±22.02) ml, operation time was(92.13±9.82) min and (106.22±11.55) min, position time was(10.00±2.14) min and (15.17±2.66) min, the differences was statistically significant(P<0.05);VAS of the two groups were (2.38±0.52) points and (4.56±0.98) points one day after surgery, respectively, with statistically significant differences (P<0.05), while VAS and ODI three months after surgery showed no statistically significant differences (P>0.05). The screw accuracy was 96.88%(62/64) in observation group and 81.48%(88/108) in control group, the difference was statistically significant(P<0.05).@*CONCLUSION@#Robot-assisted internal fixation in lateral decubitus position for the treatment of ankylosing spondylitis complicated with thoracolumbar fractures can shorten the position time and operation time, significantly improve the accuracy of internal fixation screw placement, relieve the early postoperative pain, reduce intraoperative blood loss and postoperative complications, and facilitate the fast track rehabilitation of patients.

Application of spinal surgical robots in minimally invasive surgery for thoracolumbar fracture / 中国骨伤

OBJECTIVE@#To evaluate the safety and accuracy of Renaissance robot navigation system in minimally invasive surgery for thoracolumbar fracture.@*METHODS@#The clinical data of patients with thoracolumbar fracture who underwent posterior minimally invasive pedicle screw internal fixation from July 2016 to July 2019 was retrospectively analyzed. And the patients were divided into robot group and artificial group. Robot navigation assisted screw placement was used in robot group, and traditional unarmed screw placement was used in artificial group. There were 20 patients in robot group, including 13 males and 7 females, aged from 23 to 69 years old with an average of(45.05±11.81)years old, one case was T11 fracture, 2 cases were T12, 10 cases were L1, 6 cases were L2 and 1 case was L3. There were 20 patients in artificial group, including 11 males and 9 females, aged from 26 to 65 years old with an average of(43.40±11.22)years old, 2 cases were T11 fractures, 7 cases were T12, 10 cases were L1, and 1 case was L3. The numbers of fluoroscopy, operation time and intraoperative blood loss were observed. The screw position was evaluated by Neo method.@*RESULTS@#A total of 126 screws were implanted in robot group and 124 screws were implanted in artificial group. The operation time, fluoroscopy times, intraoperative blood loss were(115.75±14.26) min, (7.95±0.89) times and (132.50±29.36) ml in robot group and (129.50±10.50) min, (14.40±2.56) times and(182.50±23.14) ml in artificial group, respectively, there was significant difference between the groups(P<0.05). According to Neo classification method, there were 122 screws at grade 0, 4 screws at grade 1 in robot group, and there were 108 screws at grade 0, 9 screws at grade 1 and 7 screws at grade 2 in artificial group. The accuracy of the robot group was better than that of artificial group(P<0.05).@*CONCLUSION@#Compared with free hand screw placement, Renaissance robot navigation system can effectively improve the accuracy of pedicle screw placement, reduce the number of fluoroscopy times and intraoperative blood loss, thereby improving the safety of operation.