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Objective:To investigate the effects of different particle sizes on the collagen structure of demineralized bone matrix (DBM) and the effectiveness of dry ice as an irradiation protectant in the procedure of gamma irradiation.Methods:DBM samples with different particle sizes (0.5-1.0 mm, 1.2-2.8 mm, 3.3-4.7 mm and 5.7-7.0 mm) were prepared, and sterilized with several doses of gamma irradiation (0 kGy, 15 kGy and 25 kGy) at room temperature. Additionally, another group of DBM samples were sterilized with 25 kGy gamma irradiation with protective agent. Changes in surface and characteristics of collagen were observed by using scanning electron microscope (SEM), Sodium dodecyl sulfatepolyacrylamide gel electrophoresis (SDS-PAGE), differential scanning calorimetry (DSC) and carbonyl content.Results:The color of collagen extract indicated that oxidative damage is directly related to irradiation dose. SEM showed that the gamma irradiation caused collagen structure disorder and fiber breakage. As the irradiation doses increased, the damage area significantly increased. When the particle size increased, the damage area tended to decrease. The DSC showed that the thermal denaturation temperature of 5.7-7 mm, 3.3-4.7 mm, 1.2-2.8 mm and 0.5-1.0 mm were 142.8℃, 97.3℃,84.3℃ and 83.9℃, respectively. The differences of the thermal denaturation temperatures among the four particle sizes were statistically significant ( F=0.560, P=0.650). Collagen structure was destroyed by gamma irradiation, resulting in a decrease in collagen molecular weight. While, large particle DBM had a tendency to resist radiation damage. There was a significant difference on the contents of carbonyl in collagen from same particle sizes of DBM with different irradiation dose. The carbonyl content gradually decreased with the increase of particle size, but the difference was not statistically significant ( F=0.560, P=0.650). Conclusion:The gamma irradiation and collagen oxidative damage have obvious dose-response relationship. With the increase of gamma irradiation dose, the degree of collagen damage increases. The sizes of DBM could affect the sensitivity of collagen to gamma irradiation. With the decrease of particle sizes, DBM particles are more susceptible to gamma irradiation damage. Additionally, dry ice, as a radiation protection agent, has a certain degree protection effect against radiation.
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Objective:To observe the epidemiological characteristics of spinal metastases by retrospectively analyzing the medical records of multicenter spinal metastases in China.Methods:Patients with spinal metastases were identified from several clinical centers between January 2007 and July 2019. A total of 1 976 patients were included in this study, including 1 129 males (57.14%) and 847 females (42.86%). The mean age was 58.6±11.6 years (range 13-92 years). The demographic characteristics, primary tumor types, spinal involvement of each patient were summarized and their clinical indicators were obtained by consulting medical records, including: Frankel grade, visual analog scale (VAS), metastatic spinal cord compression (MSCC), Tokuhashi revised score, the spinal instability neoplastic score (SINS), Karnofsky performance status (KPS), and history of malignant tumors. Finally, the intervention influencing factors of patients undergoing surgical treatment were statistically analyzed.Results:The ratio of male to female in 1 976 spinal metastases was 1.33∶1. The median age was 59.0, and most patients (63.71%) were in the ages range of 50-69. The average age of female was younger than male, and the difference was statistically significant. The proportion of male patients over 60 years old was higher than females, and the difference was statistically significant. The most common primary tumor was lung cancer (n=730, 36.94%), followed by unknown origin (n=326, 16.50%), breast cancer (n=159, 8.05%), kidney cancer (n=120, 6.07%), gastrointestinal cancer (n=109, 5.52%), etc. The most common primary tumor was lung cancer in both males and females, followed by unknown origin in males and breast cancer in females. In the past 10 years, the proportion of unknown origin has decreased, and the proportion of breast cancer has increased. According to the Tomita score, 1 284 patients (64.98%) were rapid growth tumors, 211 patients (10.68%) were moderate growth tumors, and 481 patients (24.34%) were slow growth tumors. There were 730 patients (57.14%) in the subgroup of the number<3, the most level of which was lumbar vertebrae, with 368 patients (32.60%). The remaining 847 patients (42.86%) were included in the subgroup of the number≥3, the most level of which was multiple-level of spine, with 617 patients (72.85%). Among the 1 976 patients, spinal cord injury occurred in 50.76% of patients, in which 77.18% of patients developed moderate and above pain, 14.02% of patients appeared metastatic spinal cord compression, and only 28.95% of patients had a clear history of primary tumor. In terms of treatment, 34.92% of patients underwent surgery, 5.97% underwent radiotherapy on spinal metastases, 6.02% underwent chemotherapy, and 1.77% underwent targeted therapy. Preoperative Frankel grade, SINS, and Tokuhashi revised score were important factors affecting the surgical treatment of patients.Conclusion:This study describes the epidemiological characteristics of multicenter spinal metastases in detail, which could assist orthopedic surgeons to understand the clinical characteristics of spinal metastases and was of great significance on guiding the clinical diagnoses and scientific researches.
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Objective To identify prognostic factors ofmotorfunctionafter surgery of metastatic spinal cord compression (MSCC).Methods The clinical data of 681 patients with spinal metastases from January 2008 to December 2017 were retrospectively analyzed.According to inclusion and exclusion criteria,a total of 206 patients with spinal metastatic were included.Postoperative neurological function was assessed using Frankel classification.The influence of age,gender,preoperative status,number of spine metastases,location of spinal metastases,visceral metastases,bone metastases,primary tumor type,interval from symptom to surgery,time of developing motor deficits,interval from primary tumor diagnosis to MSCC,preoperativethe Eastern Cooperative Oncology Group performance status (ECOG-PS),Karnofsky Performance score (KPS) and surgical procedures on postoperative function outcomes were explored.Results 140 (68.0%) patients were able to walk postoperatively compared with 88 (42.7%) patients preoperatively.Moreover,in 89.8% of all patients,79 ambulatory patients maintained ambulation after treatment.The univariate analysis according to Ordered-logit model showed thatnumber of spine metastases,location of spinal metastases,preoperative ECOG-PS,preoperative KPS,interval from symptom to surgery and time of developing motor deficits were related with posttreatment motor functions.The multivariable analysis showed that number of spine metastases (OR=2.03;95%CI:1.12-3.33;P=0.04),preoperative ECOG-PS (OR=4.84;95%CI:2.42-8.15;P=0.038),interval from symptom to surgery (OR=3.78;95%CI:3.12-9.15;P=0.024),time of developing motor deficits(OR=2.75;95%CI:1.22-3.89;P=0.01) were independent prognostic factors for function outcomes.Conclusion 1-2 levels of metastasis,Interval from symptom to treatment ≥ 48 h,time of developing motor deficits ≥7 d,and ECOG-PS 1-2 can be considered as the most significant positive prognosticfactors for post-treatment ambulatory status.Spinal metastasis should have a higher priority,and immediate intervention should be started before the development of irreversible neurologic deficits.Increasing awareness of early symptoms and earlier screeningwith regular outpatient review might make a difference for patients with MSCC.Consequently,the identified prognostic factors can be considered as apreoperative assessment tool to predict the neurologic outcomeand guide clinical treatment for individual patients with MSCC.
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It is a great challenge for surgeons to make an individualized treatment plan and remove tumor accurately and completely for bone tumor patients.3D printing technique is one of the most effective methods when it comes to individualized and precise treatment in medical field.The distinctiveness and advantages of 3D printing technique can make up for the shortcomings of traditional treatments,and it also can greatly improve the level and accuracy of individualized diagnosis and treatment in bone tumor surgery.3D printing technique is usually used to make anatomical models for plan or simulation;surgical guides for drilling or osteotomy;customized implants or prostheses;models for trimming grafts and models for implants in bone tumor surgery.3D printing technique is helpful to reduce operation time and bleeding,decrease radiation exposure,reduce complications and recurrence,cut the costs,and improve the surgical accuracy and clinical outcome.Through the review of 3D printing technology in bone tumor surgery literature,we analyzed and evaluated the following aspects:surgical time,bleeding,radiation exposure,clinical outcome,complications,recurrence,accuracy and costs.And the included literatures were analyzed and summarized from the positions of bone tumor and the uses of 3D printing technique.The purpose of this study is to summarize the application of 3D printing technique in treating bone tumor patients,and to make surgeons learn more about 3D printing technique,investigate the potential advantages and the developing tendency of 3D printing technique,and develop the new ideas of 3D printing technique in bone tumor surgery.
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Objective To investigate the clinical value of segmental prosthesis in the repair of diaphyseal defect.Methods The clinical data and follow-up information of 40 patients who accepted segmental prosthesis reconstruction of long bone defects in limbs were collected from June 2010 to June 2017 in General Hospital of Jinan Military Commanding and Tianjin Hospital.The parameters for outcome evaluation including general information,surgical complications,Musculoskeletal Tumor Society (MSTS) functional score,survival and prostheses status were analyzed.Results Forty patients were underwent segmental prosthesis surgery,including 18 males and 22 females,with a median age of 64 years and the age range of 13-83 years.The surgery was performed on 28 cases of femur,8 cases of humerus,3 cases of tibia,and 1 cases of ulna.There were 5 cases of primary tumor,3 cases of multiple myeloma and 32 cases of metastatic tumor of bone,in which lung cancer,breast cancer,kidney cancer,liver cancer and colorectal cancer are common.Pathological fracture of surgical site occurred in 32 cases.The average osteotomy length was 93.5 mm.The shortest osteotomy was 60 mm and the longest osteotomy was 190 mm.The average operation time was 104.6 minutes.The median bleeding volume was 600 ml.The least bleeding was 200 ml and the most bleeding was 2 800 ml.The patients median survival time was 8.5 months from 3 to 79 months.The prosthesis median survival time was 8 months from 3 to 79 months.According to the Henderson tumor prosthesis complications classification,there were 3 cases of type Ⅰ including 2 cases of incision delayed healing and 1 case of radial nerve paralysis.There was 1 case of type Ⅱ with humeral prosthesis aseptic loosening.There was 1 case of type Ⅲ with angulation deformity between femoral prosthesis force line and biological force line.There were 2 cases of type Ⅴ with tumor recurrence followed by amputation.The limb function score of MSTS was 20.4±4.1 points.Except for two patients with tumor recurrence and amputation,38 patients got stable prosthesis function until the death or follow-up cut-off.The similar tendency of patients survival curve and prosthesis survival curve indicated that survival was the main factor affecting postoperative prosthesis survivorship.Although the use rate of humeral plate (4/8,50.0%) was higher than that of femoral plate (5/28,17.9%),the difference was not statistically significant (F=3.426,P=0.064).The results of statistical analysis of complications showed that the type of tumor was an independent risk factor for complications (x2=7.446,P=0.024).The postoperative complications rate of primary tumor was significantly higher than that of multiple myeloma and bone metastasis.Patients with no complications have better limb function after surgery (F=9.709,P=0.003).Multivariate linear regression analysis showed that age,tumor type,preoperative pathologic fracture,surgery,osteotomy length did not affect limb functions after operation.The longer survival time mean better limb function (t=4.228,P=0.000).Conclusion Segmental prosthesis is a reliable method for the repair of bone metastases with defects.Combined with bone plate fixation,it can effectively reduce the occurrence of prosthetic complications.
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Objective To evaluate the prognostic factors of spinal metastases by recursive partitioning analysis (RPA)and establish a decision tree model that can guide clinicians to select individualized treatment.Methods Between January 2011 and December 2015,three institutional databases were searched to identify 169 patients with metastatic spinal tumors underwent surgery.The ratio of male and female was 1.48:1 (102 males and 67 females).The average age was 59.2±11.1 years.One-hundred eighteen cases of patients were randomly selected as training samples and the remaining 51 cases were verified samples.Preoperative factors were collected and analyzed by RPA methods,including primary tumor,KPS score,Frankel grade,gender,age,visceral metastasis,bone metastasis,spinal metastasis,blood glucose,blood pressure,surgery site,symptoms,surgery interval,serum albumin level and other risk factors.Pearson's Chi-square test was performed to judge the segmentation point of the decision tree model.The decision tree model is built using the Chi-square automatic interaction detector (CHIAD) algorithm and sensitivity and specificity was automatically calculated.Results The median postoperative survival time was 12.6±1.2 months [95%CI(10.1,15.0)].70% were randomly selected as the experimental group (118 cases),and 30% were the verification group (51 cases).The sensitivity was 96.9%.The specificity was 89.8%.The Kappa coefficient was 0.874 in the experimental group.The sensitivity was 95.4%.The specificity was 90.8%.The Kappa coefficient was 0.810 in the test group.The prognostic factors (weight from high to low) based on RPA were Frankel grade (F=8.132,P=0.005),the primary tumor and the KPS score (Equal,F=9.871,P=0.000 and F=1 1.945,P=0.003),serum albumin and movement time (Equal,F=7.566,P=0.018 and F=9.966,P=0.008).The decision tree model consists of 7 types.Survival time was 51 months,18 months,13 months,8 months,4 months,5 months,9 months in the class Ⅰ~Ⅶ,respectively.According to the difference of RPA survival time,the operation was classified as 3 grade.Total spinal resection was regarded as grade 1,including class Ⅰ and class Ⅱ,with an average survival time of over 18 months.Limited operation was regarded as grade 2,including class Ⅲ,Ⅴ and Ⅶ with survival time in 6-18 months.The conservative treatment was regarded as grade 3,including class Ⅳ and Ⅵ with the survival time was less than 6 months.Conclusion The decision tree model based on RPA for predicting the survival time of spinal metastases can not only identify the prognostic factors,but also classify and grade various prognostic factors;the decision tree model is simple and can guide clinicians to choose the best surgical plan by predicting the survival time.
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Tendon transplantation is one of the most commonly used procedures for patients with injured tendons.The materials used for tendon transplantation include the tendon autograft,tendon allograft,xenogenic tendon and artificial ligament.Of these,the allogeneic tendon has become more and more widely accepted because of the abundant donor source,absence of complications at donor sites and reduced operation time.However,it would meanwhile increase the risks of immunological rejection,disease transmission and delayed tendon-bone integration.A lot of studies have reported many processing technics to solve thementioned drawbacks of tendon allograft.Regarding to the immunological rejection,many approaches have been proposed including physical freezing (such as deep freezing,freeze drying and cryopreservation using the vitrification method) and chemical decellularization (such as deoxyguanosine culture solution,trinbutyl phosphate,chloroform / methyl alcohol,sodium dodecyl sulfate,95% ethanol and Triton X-100).Among the physical freezing methods,freeze-drying could remove the immunogenicity of tendon more effectively,but it also tends to cause damage to the mechanics,structure and histology of the tendon.And it is more likely to cause damage to tendon especially when the method is used in combination with irradiation sterilization.Deep freezing has less damage to the mechanical and histological characteristics of tendon,and this method is currently the mostcommonly used in clinical and scientific research.The vitrification preservation method has unique advantages in protecting thetendon mechanical properties and cell activity.It retains similar mechanical properties to fresh tendons.However,the complicated preparation procedures involved in this method,the high cost and the cytotoxicity of the cryoprotectant have always restrictedits application in actual production.Different chemical decellularization methods have their own advantages and disadvantages when used to reduce the immunogenicity of tendons.In order to achieve more thorough removal of cellular components in tendonswhile maximally retaining the structural and mechanical integrity of tendons,strict control on the concentration of the decellularizing agent and the treatment time is often required.