Morphometrics of T11-L5 Vertebrae in Jordanian Population: CT Scan-Based Study / Morfometría de las Vértebras T11-L5 en una Población Jordana: Estudio Basado en Tomografía Computarizada

SUMMARY: The study will provide information on the morphometrics of the vertebrae, which can be used to guide clinicians on the appropriate size of transpedicular screws to use in spine interventions among the Jordanian population and for comparative studies with other races. A retrospective analysis of normal CT scans of the lumbar and thoracolumbar areas was done. Linear and angular measurements of 336 vertebrae were collected for 25 males and 23 females. The results were compared between right and left and between both sexes. The L5 has the longest AVBH and the shortest PVBH in both sexes, it also, had the shortest and widest pedicle in both males and females. ratio of the AVBH to PVBH showed progressive increase in both sexes from T11 to L5. Similarly, the VBW increased progressively from the top to the bottom in both sexes, but it was significantly different between both sexes. The L1 was the most cranially oriented vertebrae in males while the L2 showed the most cranial orientation in females. Both sexes L5 was the most caudally oriented vertebrae. This study provides a database for vertebral morphometrics in the Jordanian population, there are slight differences between the right and left side in the upper studied vertebrae (T11-L2) and some measurement showed significant differences between males and females. These findings need to be taken into consideration when inserting pedicle screws.

Este estudio proporciona información sobre la morfometría de las vértebras, la cual puede ser utilizada por los médicos oara determinar el tamaño adecuado de los tornillos transpediculares a utilizar en intervenciones de columna en la población jordana y para estudios comparativos con otras grupos. Se realizó un análisis retrospectivo de tomografías computarizadas normales de las áreas lumbar y toracolumbar. Se recogieron medidas lineales y angulares de 336 vértebras de 25 hombres y 23 mujeres. Los resultados se compararon entre vértebras derechas e izquierdas y entre ambos sexos. La L5 tiene el AVBH más largo y el PVBH más corto en ambos sexos, también tenía el pedículo más corto y más ancho tanto en hombres como en mujeres. La relación de AVBH a PVBH mostró un aumento progresivo en ambos sexos de T11 a L5. De manera similar, el VBW aumentó progresivamente de arriba hacia abajo en ambos sexos, pero fue significativamente diferente entre ambos sexos. La L1 fue la vértebra más orientada cranealmente en los hombres, mientras que la L2 mostró la orientación más craneal en las mujeres. En ambos sexos L5 fue la vértebra más orientada caudalmente. Este estudio proporciona una base de datos para la morfometría vertebral en la población jordana, donde existen ligeras diferencias entre el lado derecho e izquierdo en las vértebras superiores estudiadas (T11-L2). Algunas mediciones mostraron diferencias significativas entre hombres y mujeres. Estos hallazgos deben tenerse en cuenta al insertar tornillos pediculares.

Pedículo Renal: Análisis de sus Variantes / Renal Pedicle: Analysis of their Variants

Testut & Latarjet (1980), Bouchet & Cuilleret (1986), Latarjet & Liard (2005) y Rouvière & Delmas (2005) describen las relaciones intrínsecas del pedículo renal (PR) a partir de dos planos coronales, siendo la PER el elemento que limita entre ambos. Trivedi et al. (2011) demostró relaciones entre los elementos del PR que no coinciden con las descripciones aportadas por dichos autores.Conocer las posibles variantes en las relaciones intrínsecas del PR es de suma importancia en prácticas quirúrgicas como el trasplante renal (García de Jalón Martínez et al., 2003; Batista Hernández et al., 2010). Por lo tanto, el objetivo del presente trabajo fue analizar las variables relaciones entre los elementos que conforman el PR en la región yuxtahiliar del riñón. Se estudiaron 23 PR, formolizados al 10 % y provistos por el Equipo de Disección de la Segunda Cátedra de Anatomía de la Universidad de Buenos Aires. Se clasificaron los PR en dos grupos. En el Grupo I, las afluentes de origen de la vena renal (AOVR) se hallaban en el mismo plano coronal. En el grupo II, las AOVR se encontraban en diferentes planos coronales. Cada grupo fue subdividido en distintos patrones. Los patrones I y II, de mayor incidencia, fueron asociados al grupo I y los patrones III, IV y V al grupo II. En el patrón I, las AOVR eran anteriores a la pelvis renal (PER) y posteriores a la arteria prepiélica (APP). En el patrón II, las AOVR eran anteriores a la PER y a la APP. Los patrones I y II conforman el grupo I y presentaron mayor número de incidencia en nuestra investigación. Existen también variantes que inciden con menor frecuencia que dichos patrones, estas comprenden el grupo II de la clasificación planteada en el presente trabajo.

SUMMARY: Testut & Latarjet (1980), Bouchet & Cuilleret (1986), Latarjet & Liard (2005) y Rouvière & Delmas (2005) describe the intrinsic relationships of the renal pedicle (PR) from two coronal planes, the renal pelvis (PER) being the element that limits between both. Trivedi et al. (2011) showed relationships between the elements of the RP that do not coincide with the descriptions provided by these authors. Knowing the possible variants in the intrinsic relationships of the RP is of the utmost importance in surgical practices such as renal transplantation (García de Jalón Martínez et al., 2003). Therefore, the objective of this study is to analyze the variable relationships between the elements that make up the RP in the juxtahilar region of the kidney. 23 RP were studied, formalized at 10 % and provided by the Dissection Team of the Second Chair of Anatomy of the University of Buenos Aires. PRs were classified into two groups. In Group I, the tributaries of origin of the renal vein (RVOA) were in the same coronal plane. In group II, the AOVRs were in different coronal planes. Each group was subdivided into different patterns. Patterns I and II, with the highest incidence, were associated with group I and patterns III, IV and V with group II. In pattern I, the VROA were anterior to the renal pelvis (PER) and posterior to the prepelvic artery (PPA). In pattern II, AOVRs were prior to PER and APP. Patterns I and II make up group I and presented a higher number of incidence in our investigation. There are also variants that occur less frequently than these patterns, these comprise group II of the classification proposed in this work.

Morphometric study and anatomical variation with its incidence of foramina transversaria on the lower cervical vertebrae / Estudio morfométrico y variación anatómica con la incidencia de forámenes transversos en las vértebras cervicales inferiores

SUMMARY: Anatomical variation of the foramina transversaria (FT) is associated with vertebral neurovascular symptoms and can cause complications after lower spine surgery, especially cervical pedicle screw (CPS) insertion. FT variation has been documented and classified in various populations, as this information can help increase cervical stability in subaxial vertebral surgery. Although the morphometry of the upper cervical spine in Thai populations has been reported, there have yet been no studies examining the features of FT. The FT of dried cervical spines (C3-C7; left and right side; n = 107, male = 53 and female = 54) were examined for morphological variation, and their anteroposterior (AP) and transverse (T) diameters were measured using a digital vernier caliper. Morphometric data and variations were compared by sex and lateral side. It was that the C3-C6 FT in both sexes were round, and the C7 FT was elliptical with an oblique right side. FT diameters did not differ significantly by sex except for the AP diameters of C6-C7 and for T diameters of C4 and C7. The left AP diameters of C3-C6 were significantly longer than the right, as were the T diameters of C4 and C7 FT. Additionally, T diameter was significantly longer than that of the AP, except that of the left C6 in male spines, which did not differ from the AP. Most FT examined were round. These findings should be considered in the provisional diagnosis of vertebral neurovascular symptoms caused by FT variation as well as that of neurovascular damage after cervical pedicle screw placement.

La variación anatómica del foramen transverso (FT) se asocia con síntomas neurovasculares vertebrales y puede causar complicaciones después de la cirugía de columna cervical inferior, especialmente la inserción de tornillos pediculares cervicales (TPC). La variación del FT se ha documentado y clasificado en varias poblaciones, ya que esta información puede ayudar a aumentar la estabilidad cervical en la cirugía vertebral subaxial. Aunque se ha informado sobre la morfometría de la columna cervical superior en poblaciones tailandesas, aún no se han realizado estudios que examinen las características de FT. Se examinó la variación morfológica del FT de vértebras cervicales secas (C3-C7; lado izquierdo y derecho; n = 107, hombres = 53 y mujeres = 54), y se midieron sus diámetros anteroposterior (AP) y transverso (T) usando un pie de metro digital. Se compararon datos morfométricos y variaciones por sexo y lado. Los FT de C3-a C6 en ambos sexos eran redondos, y el FT C7 era elíptico con el lado derecho oblicuo. Los diámetros del FT no difirieron significativamente por sexo excepto para los diámetros AP de C6- C7 y para los diámetros transversos de C4 y C7. Los diámetros AP izquierdos de C3-C6 eran significativamente más largos que los del lado derecho, al igual que los diámetros transversos de C4 y C7. Además, el diámetro transverso fue significativamente mayor que el AP, excepto el C6 izquierdo en las vértebras de hombres, que no difirió del AP. La mayoría de los FT examinados eran redondos. Estos hallazgos deben ser considerados en el diagnóstico provisional de síntomas neurovasculares vertebrales causados por la variación del FT, así como en el de daño neurovascular tras la colocación de tornillos pediculares cervicales.

A brief discussion of Glisson pedic-first approach in laparoscopic anatomical hepatectomy / 中华肝胆外科杂志

With the continuous in-depth understanding of liver anatomy and the progress of surgical techniques, laparoscopic hepatectomy has been developed rapidly, especially the laparoscopic anatomic hepatectomy has become the most commonly surgical method. The dissection and treatment of liver Glisson pedicle is the core techniques of laparoscopic anatomic hepatectomy. The Glisson hepatic pedicle approach has been widely used in open and laparoscopic anatomical hepatectomy, especially in laparoscopic hepatectomy. The possible advantages over the traditional approach are still under debate, and there is no standard surgical approach for pedicle dissection to date. This article introduces Glisson pedicle approach and the advantages and clinical application of laparoscopic anatomical hepatectomy with Glisson pedicle approach.

A clinical study of a novel manual screw placement based on anatomical study of the 7th cervical vertebra / 中华创伤骨科杂志

Objective:To evaluate the feasibility, accuracy, effectiveness and safety of a novel manual placement of cervical 7 pedicle screws via the posterior approach of cervicothoracic junction.Methods:A retrospective case series study was conducted to analyze the 35 patients with injury to the lower cervical spine or cervicothoracic junction who had been treated by a novel manual placement of cervical 7 pedicle screws at Department of Orthopedics, The First Affiliated Hospital of Zhengzhou University from March 2015 to July 2021. There were 16 males and 19 females, with an age of (52.7±13.2) years. The core of this placement was to determine the entry point of cervical 7 pedicle screws. After the intersection of the upper edge of the cervical 7 lamina and the medial edge of the superior articular process was recorded as point A while the intersection of the lateral edge of the inferior articular process and the lower edge of the transverse process as point B, the intersection of the outer and middle 1/3 of the AB line was taken as the screw entry point, with the screw placement angle perpendicular to the lamina line or slightly inclined from 30° to 40° to the head side and outward. The length, diameter and placement angle of the cervical 7 pedicle screws were recorded and compared postoperatively between the left and right sides to explore the feasibility of this novel manual placement. According to the Rampersaud method, the screw positions were graded 1 week and 6 months after operation to evaluate the accuracy of this manual placement. The visual analogue scale (VAS) and the Japanese Orthopaedic Association (JOA) score were compared between preoperation, 1 week and 6 months after operation to evaluate the effectiveness of this placement. The postoperative complications were counted to evaluate the safety of this method. Loosening, displacement and breakage of the screws were observed by CT scanning at 6 months after operation.Results:This case series was followed up for (9.8±1.7) months. There was no significant difference in the length, diameter or placement angle of the screws between the left and right sides ( P>0.05). A total of 66 cervical 7 pedicle screws were placed. There was no change in the screw position grading at 1 week or 6 months after surgery. Grade A was achieved in 64 screws, Grade B in 2 screws, and Grade C or D in none. The VAS scores before operation, 1 week and 6 months after operation were respectively 4.4±1.7, 3.8±1.0 and 1.1±1.1, and the JOA scores respectively 6.7±2.2, 13.2±1.5 and 15.3±1.2. The VAS and JOA scores at 1 week and 6 months after operation were significantly improved compared with the preoperative values ( P<0.05). The improvement rates in JOA at 1 week and 6 months after operation were 62.7%±13.3 % and 83.9%±11.6%, respectively. There were no complications related to the placement of cervical 7 pedicle screws; there was no wound hematoma or infection. No loosening, displacement or breakage of the screws was observed by the 6-month follow-up. Conclusion:The novel manual placement of cervical 7 pedicle screws via the posterior approach of cervicothoracic junction is feasible, accurate, effective and safe.

Percutaneous kyphoplasty through transverse pedicle approach for osteoporotic vertebral compression fractures / 中华创伤骨科杂志

Objective:To investigate the clinical efficacy of percutaneous kyphoplasty (PKP) through the transverse process-pedicle approach (TPPA) by comparing with PKP through the conventional transpedicle approach (CTA).Methods:A retrospective study was conducted to analyze the data of 101 patients with single-segment osteoporotic vertebral compression fracture (OVCF) who had been treated at Department of Spine Surgery, The Fourth Hospital of Wuhan from August 2020 to August 2021. There were 31 males and 70 females, with an age of (70.3±7.6) years. Their T values of bone mineral density averaged (-3.0±0.3). They were divided into a TPPA group of 52 cases in which PKP was performed through the TPPA and a CTA group of 49 cases in which PKP was performed through the CTA. The clinical efficacy was evaluated by comparing the 2 groups in terms of operation time, frequency of intraoperative fluoroscopy, excellent to good rate of bone cement distribution, rate of bone cement leakage, refractures, and visual analogue scale (VAS), Oswestry disability index (ODI) and Beck index at preoperation, 24 hours, 3 months and 6 months postoperation.Results:There was no significant difference in the preoperative general data between the 2 groups, showing they were comparable ( P>0.05). All the patients were followed up for (9.8±1.5) months. Operations were completed successfully in all patients with no complications like nerve injury or pedicle fracture. There were no significant differences in operation time, frequency of intraoperative fluoroscopy or rate of bone cement leakage between the 2 groups ( P>0.05). In the TPPA group, the excellent to good rate of bone cement distribution [92.3% (48/52)] was significantly higher than that in the CTA group [61.2% (30/49)], the VAS score [3.0 (2.0, 4.0)] and ODI (57.2±4.6) at 24 hours postoperation were significantly lower than those in the CTA group [4.0 (3.0, 4.0) and 59.2±5.3] ( P<0.05). There were no significant differences in VAS or ODI between the 2 groups at preoperation, 3 months or 6 months postoperation ( P>0.05). The VAS and ODI improved steadily within each group, showing significant differences between every 2 time points ( P<0.05). The Beck indexes [0.81 (0.69, 0.86) and 0.76 (0.67, 0.81)] at 24 hours and 6 months postoperation in the TPPA group were significantly higher than those in the CTA group [0.75 (0.71, 0.79) and 0.72 (0.68, 0.77)] ( P<0.05). The Beck indexes at 24 hours and 6 months postoperation improved significantly in all patients compared with the preoperative values ( P<0.05). Conclusions:In the treatment of OVCF with PKP, the TPPA shows the same surgical safety as CTA does, but leads to better cement distribution, better pain relief at immediate postoperation and an advantage in restoring and maintaining the height of the injured vertebral body.

Percutaneous vertebroplasty by percutaneous bi-level bilateral puncture for treatment of type ⅡA acute symptomatic osteoporotic thoracolumbar fractures with dense bone bands / 中华创伤骨科杂志

Objective:To evaluate the efficacy of percutaneous vertebroplasty (PVP) by percutaneous bi-level bilateral puncture in the treatment of type ⅡA acute symptomatic osteoporotic thoracolumbar fracture (ASOTLF) with dense bone bands.Methods:From March 2017 to March 2018, 65 patients (65 vertebrae) with type ⅡA ASOTLF with dense bone bands were treated at Department of Orthopaedic Trauma, Qingdao Central Hospital. They were 25 males and 40 females, with an age of (71.6±8.4) years. The time from injury to operation was (3.5±0.7) d. They were divided into 2 groups according to different treatments. In the observation group of 31 cases (31 vertebrae), PVP was conducted by percutaneous bi-level bilateral puncture; in the control group of 34 cases (34 vertebrae), PVP was conducted by percutaneous single-level bilateral puncture. The 2 groups were compared in terms of operation time, volume of polymethyl methacrylate injected, incidence of bone cement leakage, incidence of vertebral refracture, diffusive distribution of bone cement in the vertebral body, and visual analogue scale (VAS) and Oswestry dysfunction index (ODI) at postoperative 1 day and 6 months.Results:There was no significant difference in the preoperative general data between the 2 groups, showing comparability ( P>0.05). Operations were completed uneventfully in all the 65 patients. All the 65 patients were followed up for (8.2±1.2) months. There was no significant difference between the 2 groups in operation time, incidence of bone cement leakage or incidence of vertebral refracture for each vertebral body injured ( P>0.05). The volume of polymethyl methacrylate injected [(6.64±0.93) mL] and the excellent and good rate of diffusive distribution of bone cement in the vertebral body [87.1% (27/31)] in the observation group were significantly larger than those in the control group [(4.36±0.79) mL and 64.7% (22/34)] ( P<0.05). The VAS scores at postoperative 1 day and 6 months [2 (1, 2) and 1 (1, 2)] and ODIs at postoperative 1 day and 6 months (23.7%±1.6% and 18.8%±1.4%) in the observation group were significantly lower than those in the control group [2 (2, 3) and 2 (2, 2); 26.9%±4.2% and 22.1%±3.3%] ( P<0.05). The VAS scores and ODIs at postoperative 1 day and 6 months in all patients were significantly lower than those before operation ( P<0.05). Compression symptoms of the spinal cord and nerve root were observed in none of the patients. Conclusion:In the treatment of type ⅡA ASOTLF with dense bone bands, PVP by percutaneous bi-level bilateral puncture is more effective than the traditional PVP by percutaneous single-level bilateral puncture, and will not increase bone cement leakage or vertebral refracture.

Efficacy of O-arm combined with CT three-dimensional navigation system assisted versus manual screw placement in the treatment of lower cervical fracture and dislocation / 中华创伤杂志

Objective:To compare the clinical efficacies of O-arm combined with CT three-dimensional navigation system assisted screw placement versus manual screw placement in treating lower cervical fracture and dislocation.Methods:A retrospective cohort study was used to analyze the clinical data of 41 patients with lower cervical fracture and dislocation, who were treated in Honghui Hospital, Xi′an Jiaotong University from May 2021 to February 2022. The patients included 26 males and 15 females, aged 31.5-48.6 years [(41.5±15.0)years]. The injured segments were C 3 in 3 patients, C 4 in 12, C 5 in 13, C 6 in 10 and C 7 in 3. Nineteen patients were treated with cervical pedicle screws by O-shaped arm combined with CT three-dimensional navigation system (navigation group, 76 screws) and 22 by bare hands (traditional group, 88 screws). The total operation time, effective operation time, single nail placement time, single screw correction times, screw distance from anterior cortex, intraoperative blood loss, intraoperative fluoroscopic radiation dose, incision length and length of hospital stay were compared between the two groups, and the height of intervertebral space, Cobb angle, interbody slip distance and American Spinal injury Association (ASIA) grade were compared before operation and at 3 days after operation. Visual analogue score (VAS), Japanese Orthopedic Association (JOA) score, and neck dysfunction index (NDI) were evaluated before operation, at 3 days, 3 months after operation and at the last follow-up. Accuracy of screw placement and incidence of complications (adjacent facet joint invasion, infection, screw loosening) were detected as well. Results:All the patients were followed up for 11.1-13.9 months [(12.5±1.4)months]. The total operation time, intraoperative blood loss, intraoperative fluoroscopic radiation dose and incision length in the navigation group were more or longer than those in the traditional group (all P<0.05). The effective operation time, single nail placement time, single nail correction times and screw distance from anterior cortex in the navigation group were markedly less or smaller than those in the traditional group (all P<0.05). There was no significant difference in the length of hospital stay between the two groups ( P>0.05). There were significant improvements in the height of intervertebral space, Cobb angle and interbody slip distance between the two groups at 3 days after operation (all P<0.05). There was no significant difference in the height of intervertebral space, Cobb angle, interbody slip distance or ASIA grade between the two groups before operation or at 3 days after operation (all P>0.05). Compared with pre-operation, the VAS, JOA score and NDI were significantly improved in both groups at 3 days, 3 months after operation and at the last follow-up (all P<0.05), with further improvement with time. There was no significant difference in VAS between the two groups before operation or at 3 months after operation (all P>0.05), but it was markedly lower in the navigation group compared with the traditional group at 3 days after operation and at the last follow-up (all P<0.05). There were no significant differences in JOA score or NDI between the two groups before operation or at 3 days and 3 months after operation (all P>0.05), but both were lower in the navigation group compared with the traditional group at the last follow-up (all P<0.05). The accuracies of placement of grade 0 and grade 0+1 screws were 92.0% (70/76) and 96.6% (73/76) in the navigation group, respectively, which were markedly higher than 88.7% (78/88) and 93.5% (82/88) in the traditional group (all P<0.05). The rates of adjacent facet joint invasion of A, B, and C degrees were 71.2% (54/76), 28.8% (22/76) and 0% (0/76) in the navigation group, respectively, while the invasion rates were 60.5% (53/88), 32.3% (28/88) and 7.3% (7/88) in the traditional group ( P<0.05). No screw loosening was noted in the navigation group, but the screw loosening rate was 9.1% (8/88) in the traditional group ( P<0.01). Conclusion:Compared with manual screw placement, O-arm combined with CT three-dimensional navigation system assisted screw placement for lower cervical fracture and dislocation has the advantages of shorter effective operation time, quicker screw placement, stronger screw holding force, better cervical stability, slighter postoperative pain, higher screw placement accuracy, and lower facet joint invasion and screw loosening rates.

Anatomical analysis of C 7 pedicle screw implantation based on three-dimensional CT reconstruction model / 中华创伤杂志

Objective:To analyze the ideal entry parameters and entry points for C 7 pedicle screws based on three-dimensional CT reconstruction model. Methods:A retrospective case series study was used to analyze the cervical spine CT image data of 50 adult volunteers collected from April 2021 to March 2022 at Taizhou People′s Hospital Affiliated to Nanjing Medical University, including 25 males and 25 females; aged 20-67 years [(43.8±13.5)years]. No significant structural abnormalities were seen in the cervicothorax of all volunteers. First, the 50 CT images were imported into the medical engineering software Mimics 17.0 to reconstruct the three-dimensional C 7 model, and the C 7 pedicle screw diameter (PSD), pedicle screw length (PSL), sagittal angle (SA) and lateral angle (LA) were measured. Then, the anatomical markers, namely the lateral notch and the midpoint of the inferior edge of the C 6 articular process, were used to measure the horizontal distance between the midpoint of the inferior edge of the C 6 articular process and the ideal entry point (line segment A), and the horizontal and vertical distances between the lateral notch and the ideal entry point (line segments B and C). Finally, the lateral notch and the midpoint of the inferior edge of the C 6 articular process were used as markers to observe the distribution of entry points. The values of the above measured parameters were recorded and compared with each other to analyze the differences between different sides and genders. Intra-group correlation coefficients (ICC) were also used to assess intra- and inter-observer agreement. Results:All 100 pedicles from 50 C 7 models were accessed, with the PSD being (6.5±0.7)mm, PSL being (31.8±4.5)mm, SA being (89.8±8.8)°, LA being (31.0±6.7)°, line segment A being 0.9(-0.4, 2.1) mm, line segment B being (5.8±1.7)mm, and line segment C being (3.6±1.5)mm. All ideal entry points were located medial above the lateral notch; moreover, with the midpoint of the inferior edge of the C 6 articular process as a reference, 71 (71%) of the entry points were located laterally and 29 (29%) were located medially. The 12 mm area around the midpoint of the inferior edge of the C 6 articular process was divided into 6 sections, with 47% of the entry points being located within 2 mm lateral to the midpoint, 25% within 2 mm medial to the midpoint, 19% within 2-4 mm lateral to the midpoint, and only 9% within 50% lateral to the midpoint. The measured parameters were not significantly different between the left and right sides (all P>0.05). The PSD, SA, and line segment B in males were (6.8±0.7)mm, (92.0±8.2)°, and (6.3±1.6)mm, which were significantly greater than those in females [(6.2±0.6)mm, (87.5±8.0)°, and (5.3±1.6)mm] (all P<0.01). The remaining parameters were similar between two genders (all P>0.05). All measured parameters had high intra- and inter-observer agreement (ICC: 0.84-0.91), except for line segment A that had moderate intra- and inter-observer agreement (ICC: 0.46-0.63). Conclusions:For C 7 pedicle screw implantation, when the surface of the lateral mass is used as the reference plane, SA is approximately 90°; with reference to the lateral notch, all the ideal entry points are located medially above it; with reference to the midpoint of the inferior edge of the C 6 articular process, approximately 70% of the entry points are located laterally. There are no significant differences in the parameters between the different sides of screw implantation on pedicles. The measured parameters show high intra- and inter-observer agreement, except for line segment A.

Efficacy comparison of robot-assisted and free-hand long segment screw fixation combined with wedge osteotomy in the treatment of type IV chronic symptomatic osteoporotic thoracolumbar fractures / 中华创伤杂志

Objective:To compare the clinical efficacies of robot-assisted and free-hand long segment screw fixation combined with wedge osteotomy in the treatment of type IV chronic symptomatic osteoporotic thoracolumbar fractures (CSOVCFs).Methods:A retrospective cohort study was conducted to analyze the clinical data of 72 patients with type IV CSOVCFs who were admitted to Honghui Hospital of Xi′an Jiaotong University from May 2019 to December 2021, including 22 males and 46 females; aged 61-82 years [(71.2±12.3)years]. Fracture segments were located at T 11-T 12 in 37 patients and at L 1-L 2 in 31. A total of 32 patients were treated with robot-assisted long segment screw fixation combined with wedge osteotomy (robot group) and 36 with free-hand long segment screw fixation combined with wedge osteotomy (free-hand group). The operation time, intraoperative bleeding volume, dosage of radiation exposure, intraoperative needle adjustment, time of single pedicle screw placement and accuracy of pedicle screw placement were compared between the two groups. The kyphotic Cobb angle, sagittal vertical axis (SVA), thoracic kyphosis (TK), lumbar kyphosis (LL), visual analogue scale (VAS) and Oswestry disability index (ODI) were measured preoperatively, at 3 days postoperatively and at the last follow-up. The incidences of facet joint violation, deviation in guide needle placement, cerebrospinal leak and proximal junctional kyphosis (PJK) were observed. Results:All patients were followed up for 12-26 months [(18.2±5.1)months]. The operation time and time of single pedicle screw placement showed no significant differences between the two groups (all P>0.05). The intraoperative bleeding volume was (502.5±58.3)ml in the robot group, less than that in the free-hand group [(690.2±45.9)ml]. The dosage of radiation exposure was (32.6±10.8)μSv in the robot group, lower than that in the free-hand group [(48.6±15.2)μSv]. The intraoperative needle adjustment was (2.1±0.3)times in the robot group, higher than that in the free-hand group [(20.7±5.8)times], and the accuracy of pedicle screw placement was 99.7% in the robot group, less than that in the free-hand group (91.8%) (all P<0.01). Compared with pre-operation, the kyphotic Cobb angle, SVA, TK and LL were significantly improved in both groups at postoperative 3 days and at the last follow-up (all P<0.05). Compared with postoperative 3 days, the kyphotic Cobb angle, SVA and TK were increased at the last follow-up within the two groups, but with no significant differences (all P>0.05). Compared with postoperative 3 days, the LL was decreased within the two groups at the last follow-up, but with no significant differences (all P>0.05). The VAS and ODI in the two groups were significantly lower at postoperative 3 days and at the last follow-up when compared with those before operation (all P<0.05), and both values were significantly lower at the last follow-up than those at postoperative 3 days (all P<0.05). There were no significant differences in the VAS or ODI at all time points between the two groups (all P>0.05). The incidence of facet joint violation in the robot group was 1.6%, markedly lower than that in the free-hand group (9.6%) ( P<0.01). The incidences of deviation in guide needle placement, cerebrospinal leak and PJK showed no differences between the two groups (all P>0.05). Conclusion:For type IV CSOVCFs, the robot-assisted long segment screw fixation combined with wedge osteotomy can better reduce intraoperative blood loss, decrease radiation exposure, improve accuracy of pedicle screw placement, and reduce facet joint violation when compared with free-hand long segment screw fixation combined with wedge osteotomy.

Comparison of efficacy of O-arm assisted and free-hand pedicle screw placement in the treatment of AO type C thoracolumbar fracture / 中华创伤杂志

Objective:To compare the effect of O-arm assisted and free-hand pedicle screw placement in the treatment of AO type C thoracolumbar fracture.Methods:A retrospective cohort study was used to analyze the clinical data of 34 patients with type C thoracolumbar fracture admitted to Henan Provincial People′s Hospital from January 2018 to June 2021, including 23 males and 11 females; aged 42-63 years [(50.4±7.4)years]. The fracture was located at T 11 in 4 patients, T 12 in 10, L 1 in 12, L 2 in 6, T 11~12/L 1 in 1 and T 12/L 1 in 1. Posterior reduction and internal fixation was carried out for all patients, of whom 18 were treated with O-arm assisted pedicle screw placement (navigation group) and 16 with free-hand pedicle screw placement (free-hand group). The operation time, single screw placement time, intraoperative bleeding volume, operation mode and screw placement accuracy were compared between the two groups. The kyphotic Cobb angle, visual analogue score (VAS) and American Spinal Injury Association (ASIA) score were compared between the two groups before operation, at 1 week after operation, at 3 months after operation and at the last follow-up. Postoperative complications were observed. Results:All patients were followed up for 12-29 months [(16.8±6.1)months]. There was no significant difference between the two groups in the operation time, intraoperative bleeding volume and operation mode (all P>0.05). The single screw placement time was (9.4±1.6)minutes in navigation group, but was (10.8±1.5)minutes in free-hand group ( P<0.05). The screw placement accuracy was 97.4% in navigation group, but was 81.5% in free-hand group ( P<0.01). The kyphotic Cobb angle and VAS had no significant differences between the two groups before operation (all P>0.05). The kyphotic Cobb angle in navigation group and free-hand group was (4.3±1.1)° and (5.9±1.1)° at 1 week after operation, (4.4±1.2)° and (5.7±1.3)° at 3 months after operation, and (4.4±1.2)° and (6.8±0.9)° at the last follow-up, decreased significantly from that before operation [(21.8±3.1)°, (22.2±3.2)°] (all P<0.01). The kyphotic Cobb angle in navigation group was significantly lower than that in free-hand group at 1 week, 3 months after operation and at the last follow-up (all P<0.01). The VAS in navigation group and free-hand group was (3.2±0.7)points and (4.1±0.7)points at 1 week after operation, (2.4±0.6)points and (3.0±0.8)points at 3 months after operation, and (1.8±0.9)points and (2.6±0.7)points at the last follow-up, decreased significantly from that before operation [(8.4±0.8)points, (8.3±0.9)points] (all P<0.01). The VAS in navigation group was significantly lower than that in free-hand group at 1 week, 3 months after operation and at the last follow-up (all P<0.01). The ASIA score showed no significant difference within and between the two groups before operation, at 1 week, 3 months after operation and at the last follow-up (all P>0.05). Postoperative incision infection occurred in 1 patient in both groups ( P>0.05). Implant failure such as loosening or displacement was not observed in navigation group, and only occurred in 2 patients in free-hand group ( P>0.05). Conclusion:Compared with free-hand pedicle screw placement, O-arm assisted pedicle screw placement in the treatment of AO type C thoracolumbar fracture has advantages of rapid and accurate screw placement, good reduction and notable pain relief.

Efficacy of pedicle screws combined with vertebroplasty or intermediate screws for the treatment of osteoporotic thoracolumbar fracture: a Meta-analysis / 中华创伤杂志

Objective:To evaluate the efficacy between pedicle screws combined with vertebroplasty (PSV) and pedicle screws combined with intermediate screws (PSIS) for the treatment of osteoporotic thoracolumbar fracture (OTLF).Methods:PubMed, Cochrane Library, Web of Science, CNKI, VIP and Wanfang database were searched for all randomized controlled trial (RCT) or case-control trial (CCT) studies that comparing PSV and PSIS for the treatment of OTLF. Two reviewers independently screened the studies in the light of the inclusion and exclusion criteria, extracted data and evaluated the quality of the included studies. The Meta-analysis was performed using the RevMan 5.4 software. The subjects were divided into PSV group and PSIS group according to different treatment methods. Operation time, intraoperative blood loss, postoperative incision infection rate, postoperative short-, mid- and long-term visual analogue scale (VAS) score, postoperative short- and mid-term Oswestry disability index (ODI), hospitalization time, postoperative short-, mid- and long-term Cobb angle, postoperative short-, mid- and long-term anterior vertebral height ratio (VBH) and implant failure rate were compared between the two groups.Results:A total of 12 studies were enrolled for review, involving 870 subjects (433 in PSV group and 437 in PSIS group). The results showed insignificant difference between the two groups in operation time ( WMD=7.07, 95% CI -4.00, 18.13, P>0.05), intraoperative blood loss ( WMD=0.62, 95% CI -7.19, 8.43, P>0.05), postoperative incision infection rate ( OR=0.65, 95% CI 0.10, 4.08, P>0.05), postoperative short-term Cobb angle ( WMD=-0.19, 95% CI -0.43, 0.05, P>0.05) and postoperative short-term VBH ( WMD=0.91, 95% CI -1.30, 3.13, P>0.05). However, there was significant difference between the two groups in postoperative short-term VAS score ( WMD=-0.59, 95% CI -1.02, -0.15, P<0.05), mid-term VAS score ( WMD=-0.41, 95% CI -0.65, -0.16, P<0.05), long-term VAS score ( WMD=-0.51, 95% CI -0.59, -0.43, P<0.05), postoperative short-term ODI ( WMD=-6.26, 95% CI -9.65, -2.87, P<0.05), postoperative mid-term ODI ( WMD=-2.44, 95% CI -3.43, -1.45, P<0.05), hospitalization time ( WMD=-2.65, 95% CI -4.61, -0.68, P<0.05), postoperative mid-term Cobb angle ( WMD=-1.40, 95% CI -2.41, -0.39, P<0.05), postoperative long-term Cobb angle ( WMD=-1.06, 95% CI -1.59, -0.52, P<0.05), postoperative mid-term VBH ( WMD=3.06, 95% CI 1.31, 4.81, P<0.05), postoperative long-term VBH ( WMD=4.11, 95% CI 2.44, 5.77, P<0.05) and implant failure rate ( OR=2.06, 95% CI 0.11, 0.59, P<0.05). Conclusion:Compared with PSIS, PSV can not reduce the operation time, intraoperative blood loss and incision infection in the treatment of OTLF, but it can significantly relieve pain, improve function, decrease reduce hospitalization time, help to maintain Cobb angle and anterior vertebral height after operation, and reduce implant failure rate.

Application of measurement of pedicle parameters before L1 percutaneous vertebroplasty / 中国基层医药

Objective:The included angle of the outermost edge of the pedicle and the front edge of the central line of T12, L1, and L12 in the axial projection was compared before surgery (the incidence angle of the pedicle was set as α). A horizontal line passing through point C was made to cross the inner edge of the pedicle in the axial projection and the intersection point was designated as point D. The distance between point C and point D was compared among T12, L1, and L2. The advantages and feasibility of the measurement of these parameters for guiding puncture and bone cement injection in L1 percutaneous vertebroplasty were investigated.Methods:The clinical data of 91 patients with L1 osteoporotic vertebral compression fracture who underwent percutaneous vertebroplasty in The First People's Hospital of Chu Zhou from January 2018 to November 2021 were retrospectively analyzed. Axial α and CD of the L1 vertebral body and its adjacent vertebral bodies were measured. The amount of bone cement injected during the surgery, bone cement leakage rate, and pre- and post-surgery Visual Analogue Scale score were determined.Results:The α and CD of L1 in the axial projection were (20.43 ± 1.61)° and (5.37 ± 1.08) mm, respectively. Bone cement leakage rates of unilateral and bilateral approaches of L1 vertebral body were 35% and 12%, respectively, and there was a significant difference between the two approaches ( χ2 = 6.08, P < 0.05). There was no significant difference in the amount of bone cement injected during the surgery between unilateral and bilateral approaches of L1 ( P > 0.05). There was no significant difference in pre- and post-surgery Visual Analogue Scale scores between unilateral and bilateral approaches of L1 ( P > 0.05). Conclusion:The α and CD of L1 in the axial projection are smaller than those of other adjacent vertebral bodies, which is of great significance for selecting a puncture path and reducing bone cement leakage.

Analysis on optimal cut-off values for prediction of lumbar spinal stenosis using lumbar pedicle thickness / 中国基层医药

Objective:To investigate the optimal cut-off values for the prediction of lumbar spinal stenosis using lumbar pedicle thickness.Methods:The clinical data of 64 patients with lumbar spinal stenosis (patient group) admitted to Binzhou Center Hospital from November 2019 to April 2021 and 48 healthy volunteers (healthy control group) who concurrently received routine physical examination involving lumbar spine MRI examination in the same hospital were retrospectively analyzed. Lumbar pedicle thickness was measured on T 2 weighted images of the L 5 vertebral body in the axial projection. Lumbar pedicle thickness was compared between groups using the independent sample t-test. The relationship between lumbar pedicle thickness and age change was analyzed using a one-way analysis of variance. The efficacy of lumbar pedicle thickness in the diagnosis of lumbar spinal stenosis was evaluated using the receiver operating characteristic (ROC) curve, optimal cut-off values, sensitivity, specificity, and the area under the ROC curve. Results:There was no significant correlation between lumbar pedicle thickness and age change ( P > 0.05). Lumbar pedicle thickness of patients with lumbar spinal stenosis was significantly higher than that of healthy controls [(13.25 ± 1.73) mm vs. (8.54 ± 1.88) mm, t = 13.75, P < 0.05]. ROC curve results showed that the optimal cut-off value was 10.50 mm, with a sensitivity of 95.3% and a specificity of 85.4. The area under the ROC curve was 0.963 (95% CI 0.928-0.998). Conclusion:The increase in lumbar pedicle thickness is related to the increase in the incidence of lumbar spinal stenosis. Lumbar pedicle thickness is an accurate, objective, and clear morphological parameter for the prediction of lumbar spinal stenosis. Application of lumbar pedicle thickness to predict lumbar spinal stenosis is innovative and scientific.

Comparison of the clinical efficacy of percutaneous vertebroplasty and biopsy by unilateral and bilateral pedicle approaches for the treatment of vertebral metastasis / 中国医师进修杂志

Objective:To retrospectively compare the clinical efficacy of percutaneous vertebroplasty and biopsy by unilateral and bilateral pedicle approaches for the treatment of vertebral metastasis.Methods:From June 2020 to July 2022, a total of 82 patients with vertebral metastasis underwent percutaneous vertebroplasty and biopsy treated in Linyi Cancer Hospital were enrolled, 39 patients with 57 vertebral bodies were performed by unilateral pedicle approach (unilateral group) and 43 patients with 52 vertebral bodies were performed by bilateral pedicle approaches (bilateral group), used bone cement filling vertebral bodies after biopsy. The clinical efficacy and the positive rate of biopsy were compared between the two groups.Results:Both groups experienced significant pain relief in the Visual Analog Scale (VAS) score and improvement in the Oswestry Disability Index (ODI) score after operation ( P<0.05), but there were no significant differences between the two groups ( P>0.05). The operative time for a single vertebra, volume of bone cement in unilateral group were less than those in the bilateral group:(44.81 ± 13.01) min vs. (31.84 ± 11.87) min, (4.87 ± 0.92) ml vs. (4.18 ± 0.90) ml, there were significant differences ( P<0.05). There were no significant differences in the incidence of bone cement leakage and the positive rate of biopsy between both groups ( P>0.05). Conclusions:Percutaneous vertebroplasty and biopsy by unilateral and bilateral pedicle approaches are significant improvement for symptoms and functions of patients with vertebral metastasis. The clinical efficacy and the positive rate of biopsy are similar. But the former has easier operation procedure, shorter operative time and less volume of bone cement.

Application value of cystic plate approach for extrahepatic right hepatic pedicle dissection in minimally invasive anatomic liver resection / 中华消化外科杂志

Objective:To investigate the application value of cystic plate approach (CPA) for extrahepatic right hepatic pedicle dissection in minimally invasive anatomical hepatectomy (MIALR).Methods:The retrospective cohort study was conducted. The clinicopathological data of 42 patients with primary liver cancer who underwent laparoscopic right hemi-hepatectomy in Nanfang Hospital of Southern Medical University from August 2020 to August 2022 were collected. There were 36 males and 6 females, aged (55±13)years. Of the 42 patients, 25 cases undergoing CPA for extrahepatic right hepatic pedicle dissection were divided into the CPA group, and 17 cases undergoing traditional approach for extrahepatic right hepatic pedicle dissection were divided into the traditional approach group. Observation indicators: (1) surgical situations; (2) postoperative situations. Measurement data with normal distribution were represented as Mean± SD, and comparison between groups was conducted using the t test. Measurement data with skewed distribution were represented as M( IQR), and comparison between groups was conducted using the Mann-Whitney U test. Count data were described as absolute numbers, and comparison between groups was conducted using the chi-square test or Fisher exact probability. Comparison of ordinal data was conducted using the non‐parameter rank sum test. Results:(1) Surgical situations. All patients in the two groups underwent laparos-copic right hemi-hepatectomy successfully, with the surgical margin as negative. The operation time, volume of intraoperative blood loss, time of dissection of the targeted hepatic pedicle, cases under-going dissection of the trunk of right anterior hepatic pedicle and its operation time, cases under-going dissection of the trunk of right posterior hepatic pedicle and its operation time, cases with hepatic pedicle injury, cases with hepatic tissue injury, cases with dissection space as large and small were 150.00(130.00)minutes, 100.00(100.00)mL, 472.00(201.00)seconds, 10 and 366.00(94.75)seconds, 9 and 564.00(138.50)seconds, 2, 2, 25, 0 in patients of the CPA group, versus 140.00(113.00)minutes, 100.00(125.00)mL, 670.00(107.00)seconds, 8 and 663.00(136.00)seconds, 7 and 783.00(189.00)seconds, 8, 5, 2, 19 in patients of the traditional approach group. There were significant differences in the time of dissection of the targeted hepatic pedicle, time of dissection of the trunk of right anterior hepatic pedicle, time of dissection of the trunk of right posterior hepatic pedicle, hepatic pedicle injury, dissection space between the two groups ( Z=-4.809, -3.254, -3.188, χ2=6.493, 34.314, P<0.05) and there was no significant difference in the operation time, volume of intraoperative blood loss, dissection of the trunk of right anterior hepatic pedicle, dissection of the trunk of right posterior hepatic pedicle, hepatic tissue injury between the two groups ( Z=-0.282, -0.412, χ2=0.095, 0.002, 1.976, P>0.05). (2) Postoperative situations. There was no patient under-going postoperative hemorrhage in both of the two groups. The alanine transaminase (ALT), aspartate transaminase (AST), total bilirubin (TBil) and prothrombin time (PT) at postoperative day 3, cases with postoperative biliary fistula, pathological type of tumor (hepatocellular carcinoma, intrahepatic cholangiocarcinoma) were 68.00(48.50)U/L, 52.00(35.50)U/L, 28.30(12.35)mmol/L, 12.40(2.40)seconds, 2, 21, 4 in patients of the CPA group. The above indicators were 58.00(25.00)U/L, 41.00(19.50)U/L, 26.80(14.25)mmol/L, 12.50(2.95)seconds, 5, 15, 2 in patients of the traditional approach group. There was no significant difference in the ALT, AST, TBil, PT at postoperative day 3, postoperative biliary fistula between the two groups ( Z=-1.218, -1.488, -0.205, -0.320, χ2=1.976, P>0.05), and there was no significant difference in the pathological type of tumor between the two groups ( P>0.05). Conclusion:Application of CPA for extrahepatic right hepatic pedicle dissection in MIALR is safe and feasible.

Application value of cystic plate approach for extrahepatic right hepatic pedicle dissection in minimally invasive anatomic liver resection / 中华消化外科杂志

Objective:To investigate the application value of cystic plate approach (CPA) for extrahepatic right hepatic pedicle dissection in minimally invasive anatomical hepatectomy (MIALR).Methods:The retrospective cohort study was conducted. The clinicopathological data of 42 patients with primary liver cancer who underwent laparoscopic right hemi-hepatectomy in Nanfang Hospital of Southern Medical University from August 2020 to August 2022 were collected. There were 36 males and 6 females, aged (55±13)years. Of the 42 patients, 25 cases undergoing CPA for extrahepatic right hepatic pedicle dissection were divided into the CPA group, and 17 cases undergoing traditional approach for extrahepatic right hepatic pedicle dissection were divided into the traditional approach group. Observation indicators: (1) surgical situations; (2) postoperative situations. Measurement data with normal distribution were represented as Mean± SD, and comparison between groups was conducted using the t test. Measurement data with skewed distribution were represented as M( IQR), and comparison between groups was conducted using the Mann?Whitney U test. Count data were described as absolute numbers, and comparison between groups was conducted using the chi?square test or Fisher exact probability. Comparison of ordinal data was conducted using the non‐parameter rank sum test. Results:(1) Surgical situations. All patients in the two groups underwent laparoscopic right hemi-hepatectomy successfully, with the surgical margin as negative. The operative time, volume of intraoperative blood loss, time of dissection of the targeted hepatic pedicle, cases undergoing dissection of the trunk of right anterior hepatic pedicle and its operation time, cases undergoing dissection of the trunk of right posterior hepatic pedicle and its operation time, cases with hepatic pedicle injury, cases with hepatic tissue injury, cases with dissection space as large and small were 150.00(130.00)minutes, 100.00(100.00)mL, 472.00(201.00)seconds, 10 and 366.00(94.75)seconds, 9 and 564.00(138.50)seconds, 2, 2, 25, 0 in patients of the CPA group, versus 140.00(113.00)minutes, 100.00(125.00)mL, 670.00(107.00)seconds, 8 and 663.00(136.00)seconds, 7 and 783.00(189.00)seconds, 8, 5, 2, 19 in patients of the traditional approach group. There were significant differences in the time of dissection of the targeted hepatic pedicle, time of dissection of the trunk of right anterior hepatic pedicle, time of dissection of the trunk of right posterior hepatic pedicle, hepatic tissue injury, dissection space between the two groups ( Z=-4.809, -3.254, -3.188, χ2=6.493, 34.314, P<0.05) and there was no significant difference in the operation time, volume of intraoperative blood loss, dissection of the trunk of right anterior hepatic pedicle, dissection of the trunk of right posterior hepatic pedicle, hepatic tissue injury between the two groups ( Z=-0.282, -0.412, χ2=0.095, 0.002, 1.976, P>0.05). (2) Postoperative situations. There was no patient undergoing postoperative hemorrhage in both of the two groups. The alanine transaminase (ALT), aspartate transaminase (AST), total bilirubin (TBil) and prothrombin time (PT) at postoperative day 3, cases with postoperative biliary fistula, pathological type of tumor (hepatocellular carcinoma, intrahepatic cholangiocarcinoma) were 68.00(48.50)U/L, 52.00(35.50)U/L, 28.30(12.35)mmol/L, 12.40(2.40)seconds, 2, 21, 4 in patients of the CPA group. The above indicators were 58.00(25.00)U/L, 41.00(19.50)U/L, 26.80(14.25)mmol/L, 12.50(2.95)seconds, 5, 15, 2 in patients of the traditional approach group. There was no significant difference in the ALT, AST, TBil, PT at postoperative day 3, cases with postoperative biliary fistula between the two groups ( Z=-1.218, -1.488, -0.205, -0.320, χ2=1.976, P>0.05), and there was no significant difference in the pathological type of tumor between the two groups ( P>0.05). Conclusion:Application of CPA for extrahepatic right hepatic pedicle dissection in MIALR is safe and feasible.

Biomechanical Comparison of Internal Fixation by Traditional and Cortical Bone Trajectory Pedicle Screw / 医用生物力学

Objective To compare the effects of cortical bone trajectory ( CBT) and traditional trajectory ( TT)pedicle screw internal fixation on the range of motion (ROM) and rod system stress of normal and osteoporotic(OP) spines. Methods The L3-S1 finite element models of normal and OP spines were established. The screwrod system with two kinds of trajectory was used for internal fixation of the L4-5 segment, so as to simulate sixphysiological loads, namely, flexion, extension, left / right bending, left / right rotation. The effects of two internalfixation methods on ROMs and maximum equivalent stress of screws in normal and OP spines were compared.Results For both bone conditions, CBT and TT significantly reduced ROM of the fixed segment (L4-5) and theentire segment of lower lumbar spine ( L3-S1). However, the ROM decline of CBT group was slightly smaller than that of TT group, and their ROMs were similar under flexion and extension, but the ROM differences were significant under lateral bending and axial rotation. In addition, for both the normal and OP spine models, themaximum equivalent stress of screws in CBT group was significantly higher than that in TT group. Compared withTT group, the screw stress of CBT group in normal spine model under flexion and extension, lateral bending,axial rotation was increased by 27% , 268% and 58% , respectively. However, when CBT technique was used atthe same time, the OP spine model had a smaller screw stress distribution than the normal spine model.Conclusions Compared with TT technique, CBT technique can achieve higher screw stress under OP conditionand reduce screw stress concentration under normal bone condition. In addition, CBT slightly increases ROMs of each segment, which is conducive to recovery of spinal physiological function after surgery. Lateral bending and axial rotation can produce negative mechanical effects, and these two physiological loads should be avoided.

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 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.