【Abstract】 Objective To explore the biomechanical properties of a new intramedullary controlled dynamicnail ing (ICDN). Methods Ten pairs of specimens of adult femurs, with the age of 18 to 55 years, were divided into twogroups (groups A1 and B2, n=10). The length of the specimens was (438 ± 10) mm , and the external diameter was (26.4 ± 1.5) mm. The specimens of the two groups were osteotomized transversely after the biomechanical test. ICDNs and GK nails were randomly implanted into the femurs, respectively (groups A2 and B2). Torsional, bending and axial compressive tests were made in each group, and the effect of dynamic compression between the fracture fragments was tested. Results The resistance to compression of groups A1, B1, A2 and B2 were (0.19 ± 0.18) × 106, (0.22 ± 0.12) × 106, (1.67 ± 0.68) × 106 and (0.86 ± 0.32) × 106 N/mm, respectively. There was statistically significant difference between groups A2 and B2 (P lt; 0.01). The bending stiffnesses of coronal section of groups A1, B1, A2 and B2 were (0.94 ± 0.25) × 103, (1.10 ± 0.21) × 103, (0.70 ± 0.22) × 103, (0.64 ± 0.21) × 103 N/mm, respectively. The bending stiffness of sagittal plane of groups A1, B1, A2 and B2 were (1.06 ± 0.26) × 103, (0.96 ± 0.25) × 103, (0.67 ± 0.25) × 103, (0.61 ± 0.18) × 103 N/mm, respectively. There were no statistically significant differences between groups A1 and B1 or between groups A2 and B2 (P gt; 0.05). When the torque was 5 Nm, the torsional stiffness of groups A1, B1, A2 and B2 were (4.00 ± 2.54), (4.76 ± 1.93), (0.50 ± 0.63), (0.35 ± 0.31) Nm/°, respectively. When the torque was8 Nm, the torsional stiffness of groups A1, B1, A2 and B2 were (4.30 ± 3.27), (3.94 ± 2.01), (0.42 ± 0.52), (0.36 ± 0.18) Nm/°, respectively. There were statistically significant differences between groups A1 and A2 or between groups B1 and B2 (P lt; 0.05), and no statistically significant difference between between groups A2 and B2 (P gt; 0.05). The average maximal pressure generated between the fracture fragments which were fixed with ICDN was 21.6 N, and the pressure between the fracture fragments which were fixed with GK nail ing could not be tested. Conclusion The design of ICDN conforms to the special anatomical structure of the femur. ICDN could provide a completely different structure, a different fixation principal and a more balancedfixation than GK nail. ICDN incorporates the flexible and rigid fixation, which is l ikely to be the trend of the fracture fixation.
Objective To investigate the change of immunologic gene expression in cases of colorectal cancer with liver metastasis. Methods The total RNAs were extracted from tumor tissues of original lesions in 16 patients with colorectal cancer， DNA microarray was used to examine the change of immunologic gene expression in colorectal cancer patients with or without liver metastasis. Results Compared with samples without liver metastases， the expressions of 11 immunologic genes obviously down-regulated in the tumor tissues of colorectal cancer patients with liver metastasis， including：carboxypeptidase D；Fc fragment of IgE， high affinityⅠreceptor for gamma polypeptide；Fc fragment of IgG， low affinityⅢa receptor （CD16a）；free fatty acid receptor 2；interleukin 2 receptor gamma；protein tyrosine phosphatase receptor type C；complement factor B；major histocompatibility complex， classⅡ， DM alpha；major histocompatibility complex， classⅡ， DM beta；major histocompatibility complex， classⅡ， DQ alpha 1；granzyme B. The functions involved the growth and activation of immunologic cell， signal transduction， cell apoptotic， cell factors， receptors， complement， apoptotic， and immunogenicity of tumor cell. Conclusions Down-regulation of a various of immunologic gene expression in colorectal cancer patients with liver metastasis inhibits the function of immunology， and tumor cells escaped the destruction of immunology system results in metastasis.
Objective To analyze the impact of ivaroxaban on hidden blood loss and blood transfusion rate after primary total knee arthroplasty (TKA) by comparing with the use of low molecular weight heparin. Methods Between December 2009 and January 2011, the clinical data from 90 patients undergoing primary TKA were retrospectively analyzed. At 12 hours after operation, 45 patients were given ivaroxaban (10 mg/d) in the trial group and low molecular weight heparin injection (0.4 mL/d) in the control group for 14 days, respectively. There was no significant difference in gender, age, disease duration, or range of motion between 2 groups (P gt; 0.05). Results The operation time was (92.32 ± 23.13) minutes in the trial group and (89.81 ± 18.65) minutes in the control group, showing no significant difference (t=0.26, P=0.79). The hidden blood loss was (40.18 ± 14.85) g/L in the trial group and (34.04 ± 12.96) g/L in the control group, showing significant difference (t=2.09, P=0.00); the dominant blood loss was (30.60 ± 2.89) g/L and (28.85 ± 8.10) g/L respectively, showing no significant difference (t= 1.37, P=0.17). The blood transfusion rate was 73.33% (33/45) in the trial group and 55.56% (25/45) in the control group, showing no sigificant difference (χ2=3.10, P=0.08); the transfusion volume was (1.44 ± 1.09) U and (1.06 ± 1.17) U respectively, showing no significant difference (t=1.58, P=0.11). Stress ulcer occurred in 1 case of the trial group; symptomatic deep vein thrombosis of lower extremity and asymptomatic muscular venous thrombosis developed in 1 case and 4 cases of the control group respectively. Conclusion Ivaroxaban has effect on the hidden blood loss after primary TKA, which may increase postoperative blood loss and blood transfusion rate. The changes in hemoglobin should be monitored during the anticoagulant therapy, and the blood volume should be added promptly.
ObjectiveTo investigate the effectiveness of percutaneous double-segment lengthened sacroiliac screws internal fixation assisted by three-dimensional (3D) navigation technology in treatment of Denis type Ⅱ and Ⅲ sacral fractures. Methods A clinical data of 45 patients with the Denis type Ⅱ and Ⅲ sacral fractures admitted between January 2017 and May 2020 was retrospectively analyzed. There were 31 males and 14 females, with an average age of 48.3 years (range, 30-65 years). The pelvic fractures were all high energy injuries. According to the Tile classification standard, there were 24 cases of type C1, 16 cases of type C2, and 5 cases of type C3. The sacral fractures were classified as Denis type Ⅱ in 31 cases and type Ⅲ in 14 cases. The interval between injury and operation was 5-12 days (mean, 7.5 days). The lengthened sacroiliac screws were implanted in S1 and S2 segments respectively under the assistance of 3D navigation technology. The implantation time of each screw, the intraoperative X-ray exposure time, and the occurrence of surgical complications were recorded. After operation, the imaging reexamination was used to evaluate the screw position according to Gras standard and the reduction quality of sacral fractures according to Matta standard. At last follow-up, the pelvic function was scored with Majeed scoring standard. Results The 101 lengthened sacroiliac screws were implanted with the assisting of 3D navigation technology. The implantation time of each screw was 37.3 minutes on average (range, 30-45 minutes), and the X-ray exposure time was 46.2 seconds on average (range, 40-55 seconds). All patients had no neurovascular or organ injury. All incisions healed by first intention. The quality of fracture reduction was evaluated according to Matta standard as excellent in 22 cases, good in 18 cases, and fair in 5 cases, and the excellent and good rate was 88.89%. The screw position was evaluated according to Gras standard as excellent in 77 screws, good in 22 screws, and poor in 2 screws, and the excellent and good rate was 98.02%. All patients were followed up 12-24 months (mean, 14.6 months). All fractures healed and the healing time was 12-16 weeks (mean, 13.5 weeks). Pelvic function was evaluated according to Majeed scoring standard as excellent in 27 cases, good in 16 cases, fair in 2 cases, and the excellent and good rate was 95.56%. Conclusion Percutaneous double-segment lengthened sacroiliac screws internal fixation for the treatment of Denis type Ⅱ and Ⅲ sacral fractures is minimally invasive and effective. With the assistance of 3D navigation technology, the screw implantation is accurate and safe.
Objective To investigate the effectiveness of osteotomy of non-core weight-bearing area of the lateral tibial plateau, reduction, and internal fixation in the treatment of tibial plateau fractures involving posterolateral column collapse. Methods A clinical data of 23 patients with tibial plateau fractures involving posterolateral column collapse, who had undergone osteotomy of non-core weight-bearing area of the lateral tibial plateau, reduction, and internal fixation between January 2015 and June 2021, was retrospectively analyzed. There were 14 males and 9 females with an average age of 42.6 years ranging from 26 to 62 years. The causes of injury included traffic accident in 16 cases, falling from height in 5 cases, and other injuries in 2 cases. According to Schatzker classification, there were 15 cases of type Ⅴ and 8 cases of type Ⅵ. The time from injury to operation was 4-8 days with an average of 5.9 days. The operation time, intraoperative blood loss, fracture healing time, and complications were recorded. The depth of articular surface collapse of posterolateral column and posterior inclination angle (PSA) of the tibial plateau were compared before operation and at 2 days and 6 months after operation; fracture reduction of tibial plateau fracture was evaluated by Rasmussen anatomic score. The recovery of knee function was evaluated by Hospital for Special Surgery (HSS) score at 2 days and 6 months after operation. Results All 23 patients were completed the operation successfully. The operation time was 120-195 minutes, with an average of 152.8 minutes; the intraoperative blood loss was 50-175 mL, with an average of 109.5 mL. All patients were followed up 12-24 months, with an average of 16.7 months. One patient had superficial wound infection after operation, and the incision healed after dressing change; primary healing of incision of other patients was obtained. The fracture healing time was 12-18 weeks, with an average of 13.7 weeks. No failure of internal fixation, varus and valgus deformity of the knee joint, and instability of the knee joint was found at last follow-up. One patient developed joint stiffness and the range of motion of the knee joint was 10°-100°; the range of motion of the knee joint of other patients was 0°-125°. At 2 days and 6 months after operation, the depth of articular surface collapse of posterolateral column, PSA, and Rasmussen anatomic scores significantly improved when compared with those before operation (P<0.05). There was no significant difference between the two postoperative time points (P>0.05). The HSS score at 6 months after operation was significantly higher than that at 2 days after operation (P<0.05). Conclusion For tibial plateau fractures involving posterolateral column collapse, reduction and internal fixation through osteotomy of non-core weight-bearing area of the lateral tibial plateau has the advantages of fully expose the posterolateral column fragment, good articular surface reduction, sufficient bone grafting, and fewer postoperative complications. It is beneficial to restore knee joint function and can be widely used in clinic.
Objective To summarize the latest developments in neurosurgical treatments for neurofibromatosis type 1 (NF1) and explore therapeutic strategies to provide comprehensive treatment guidelines for clinicians. Methods The recent domestic and international literature and clinical cases in the field of NF1 were reviewed. The main types of neurological complications associated with NF1 and their treatments were thorough summarized and the future research directions in neurosurgery was analyzed. Results NF1 frequently results in complex and diverse lesions in the central and peripheral nervous systems, particularly low-grade gliomas in the brain and spinal canal and paraspinal neurofibromas. Treatment decisions should be made by a multidisciplinary team. Symptomatic plexiform neurofibromas and tumors with malignant imaging evidence require neurosurgical intervention. The goals of surgery include reducing tumor size, alleviating pain, and improving appearance. Postoperative functional rehabilitation exercises, long-term multidisciplinary follow-up, and psychosocial interventions are crucial for improving the quality of life for patients. Advanced imaging guidance systems and artificial intelligence technologies can help increase tumor resection rates and reduce recurrence. Conclusion Neurosurgical intervention is the primary treatment for symptomatic plexiform neurofibromas and malignant peripheral nerve sheath tumors when medical treatment is ineffective and the lesions progress rapidly. Preoperative multidisciplinary assessment, intraoperative electrophysiological monitoring, and advanced surgical assistance devices significantly enhance surgical efficacy and safety. Future research should continue to explore new surgical techniques and improve postoperative management strategies to achieve more precise and personalized treatment for NF1 patients.
Objective To compare the biomechanical differences among the five internal fixation modes in treatment of Day type Ⅱ crescent fracture dislocation of pelvis (CFDP), and find an internal fixation mode which was the most consistent with mechanical principles. Methods Based on the pelvic CT data of a healthy adult male volunteer, a Day type Ⅱ CFDP finite element model was established by using Mimics 17.0, ANSYS 12.0-ICEM, Abaqus 2020, and SolidWorks 2012 softwares. After verifying the validity of the finite element model by comparing the anatomical parameters with the three-dimensional reconstruction model and the mechanical validity verification, the fracture and dislocated joint of models were fixed with S1 sacroiliac screw combined with 1 LC-Ⅱ screw (S1+LC-Ⅱ group), S1 sacroiliac screw combined with 2 LC-Ⅱ screws (S1+2LC-Ⅱ group), S1 sacroiliac screw combined with 2 posterior iliac screws (S1+2PIS group), S1 and S2 sacroiliac screws combined with 1 LC-Ⅱ screw (S1+S2+LC-Ⅱ group), S2-alar-iliac (S2AI) screw combined with 1 LC-Ⅱ screw (S2AI+LC-Ⅱ group), respectively. After each internal fixation model was loaded with a force of 600 N in the standing position, the maximum displacement of the crescent fracture fragments, the maximum stress of the internal fixation (the maximum stress of the screw at the ilium fracture and the maximum stress of the screw at the sacroiliac joint), sacroiliac joint displacement, and bone stress distribution around internal fixation were observed in 5 groups. Results The finite element model in this study has been verified to be effective. After loading 600 N stress, there was a certain displacement of the crescent fracture of pelvis in each internal fixation model, among which the S1+LC-Ⅱ group was the largest, the S1+2LC-Ⅱ group and the S1+2PIS group were the smallest. The maximum stress of the internal fixation mainly concentrated at the sacroiliac joint and the fracture line of crescent fracture. The maximum stress of the screw at the sacroiliac joint was the largest in the S1+LC-Ⅱ group and the smallest in the S2AI+LC-Ⅱ group. The maximum stress of the screw at the ilium fracture was the largest in the S1+2PIS group and the smallest in the S1+2LC-Ⅱ group. The displacement of the sacroiliac joint was the largest in the S1+LC-Ⅱ group and the smallest in the S1+S2+LC-Ⅱ group. In each internal fixation model, the maximum stress around the sacroiliac screws concentrated on the contact surface between the screw and the cortical bone, the maximum stress around the screws at the iliac bone concentrated on the cancellous bone of the fracture line, and the maximum stress around the S2AI screw concentrated on the cancellous bone on the iliac side. The maximum bone stress around the screws at the sacroiliac joint was the largest in the S1+LC-Ⅱ group and the smallest in the S2AI+LC-Ⅱ group. The maximum bone stress around the screws at the ilium was the largest in the S1+2PIS group and the smallest in the S1+LC-Ⅱ group. Conclusion For the treatment of Day type Ⅱ CFDP, it is recommended to choose S1 sacroiliac screw combined with 1 LC-Ⅱ screw for internal fixation, which can achieve a firm fixation effect without increasing the number of screws.
Objective To compare the effectiveness of O-arm navigation and C-arm navigation for guiding percutaneous long sacroiliac screws in treatment of Denis type Ⅱ sacral fractures. Methods A retrospective study was conducted on clinical data of the 46 patients with Denis type Ⅱ sacral fractures between April 2021 and October 2022. Among them, 19 patients underwent O-arm navigation assisted percutaneous long sacroiliac screw fixation (O-arm navigation group), and 27 patients underwent C-arm navigation assisted percutaneous long sacroiliac screw fixation (C-arm navigation group). There was no significant difference in gender, age, causes of injuries, Tile classification of pelvic fractures, combined injury, the interval from injury to operation between the two groups (P>0.05). The intraoperative preparation time, the placement time of each screw, the fluoroscopy time of each screw during placement, screw position accuracy, the quality of fracture reduction, and fracture healing time were recorded and compared, postoperative complications were observed. Pelvic function was evaluated by Majeed score at last follow-up. Results All operations were completed successfully, and all incisions healed by first intention. Compared to the C-arm navigation group, the O-arm navigation group had shorter intraoperative preparation time, placement time of each screw, and fluoroscopy time, with significant differences (P<0.05). There was no significant difference in screw position accuracy and the quality of fracture reduction (P>0.05). There was no nerve or vascular injury during screw placed in the two groups. All patients in both groups were followed up, with the follow-up time of 6-21 months (mean, 12.0 months). Imaging re-examination showed that both groups achieved bony healing, and there was no significant difference in fracture healing time between the two groups (P>0.05). During follow-up, there was no postoperative complications, such as screw loosening and breaking or loss of fracture reduction. At last follow-up, there was no significant difference in pelvic function between the two groups (P>0.05). Conclusion Compared with the C-arm navigation, the O-arm navigation assisted percutaneous long sacroiliac screws for the treatment of Denis typeⅡsacral fractures can significantly shorten the intraoperative preparation time, screw placement time, and fluoroscopy time, improve the accuracy of screw placement, and obtain clearer navigation images.