BACKGROUND: There are various kinds of design methods about preoperative osteotomy of ankylosing spondylitis with kyphosis, but each has their own errors and limitations. A convenient, precise and available method needs to bedeveloped.OBJECTIVE: To compare the clinical efficacy of two different preoperative osteotomy designs using paper-cut andphotoshop software for ankylosing spondylitis with kyphosis.METHODS: Thirty-nine patients suffering ankylosing spondylitis with kyphosis undergoing osteotomy in the Departmentof Spinal Surgery, Affiliated Hospital of Yan'an University between June 2009 and January 2015 were enrolled, andrandomly allotted to paper-cut (n=19) and photoshop (n=20) groups, followed by the preoperative osteotomy design,respectively. All patients were followed for 12-40 months to compare the postoperative osteotomy angle error andcorrection efficacy at the last follow-up between groups.RESULTS AND CONCLUSION: (1) The postoperative osteotomy angle error in the photoshop group was significantly smaller than that in the paper-cut group (P < 0.05). (2) At the last follow-up, the key parameters of sagittal spine and pelvis (sagittal vertical axis, Cobb angle and pelvic tilt) showed significant differences between groups (P < 0.05). (3) The Oswestry disability index and Scoliosis Research Society-22 questionnaire scores in the photoshop group weresignificantly superior to those in the paper-cut group at the last follow-up (P < 0.05), while the visual analog scale scoresdid not differ significantly between groups (P > 0.05). (4) To conclude, compared with the osteotomy design usingtraditional paper-cut splice, the photoshop software can achieve a smaller osteotomy angle error and better postoperative balance of spinal sagittal plane, thus providing precise osteotomy for surgeons to obtain proper correction.

Objective To introduce the application of 3D printing individualized plastic guide plate in the treatment of pelvic and acetabular fracture and to evaluate its application value.Methods From June 2016 to April 2017,the clinical data of eleven adult patients with pelvic and acetabular fracture was analyzed retrospectively.The pelvic CT scan was performed before operation to obtain the original data.Three-dimensional reconstruction performed by mimics 17.0 software with the data and the fracture reduction performed on the software.3D printing individualized plastic guide plate was designed and made to guide the pre-implantation plate bending and shaping.The pre implantation plate bending was completed according to the plastic guide.Postoperative Matta imaging score was used to evaluate fracture reduction,while the function of the hip joint was assessed by the Harris scores.Results All the operations were successfully completed.There were no adverse complications during or after the operation.Anatomical reduction was performed in 10 cases and functional reduction in 1 case.The excellent and good rate of Matta scores was 90.9%,excellent in 7 cases,good in 3 cases,fair in 1 case and no poor case.The excellent rate of Harris scores was 81.8%,excellent in 6 cases, good in 3 cases,fair in 2 cases and no poor case.Conclusion In the treatment of pelvic and acetabular fracture,the application of 3D printing individualized plastic guide plate may not only make mode simple and feasible and save time and materials,but also simplify the operation,reduce the difficulty of operation and hold satisfactory clinical effect.

Objective To introduce the method of using hollow pull screw insertion for the suprapubic fracture with 3D printing navigation template and to evaluate its clinical effect.Methods From March 2016 to August 2017,eighteen cases of suprapubic ramus fractures treated with hollow lag screw fixation in the Department of Orthopedics of Yanan University Affiliated Hospital were retrospectively collected was collected.Before operation,the thin slice CT scan of pelvis was used to get raw data,and the mimics17.0 software was used to reconstruction the model,to design and make the personalized navigation template assisting the suprapubic fractures surgery.The navigation template was printed out pre-operatively,and the nail was inserted via the assisted by the template intra-operatively.After the operation,the fracture reduction was evaluated by Matta imaging scores and the pelvis function was evaluated by Majeed scores.Results All the operations were successfully completed.The Matta scores were excellent in 11 cases,good in 6 cases,and fair in 1 case.The Majeed scores were excellent in 13 cases,good in 3 cases,and fair in 2 cases.Conclusion 3D Printing navigation template assisted the placement of the hollow screw on the suprapubic fracture could provide personalized treatment,reduce the difficulty of operation and satisfy the clinical effect.

Objective To investigate the clinical value of 3D printing technique in the treatment of adult displaced clavicle fracture.Methods The clinical data of forty adult patients with displaced clavicle fracture treated in Yan' an University Affiliated Hospital from January 2016 to December 2016 were retrospectively collected.According to different surgical methods,the patients were divided into group A and group B,with 20 cases in each group.The group A received the CT scan of the uninjured lateral clavicle before operation to obtain the original data.The mimics 17.0 software was used to perform 3D reconstruction and to generate the affected side mirror model.The 3D printer was introduced to print the affected mirror model.According to the model of preoperative planning,minimally invasive surgery was performed under model guidance.The group B(20 cases)was underwent minimally invasive surgery via conventional C arm fluoroscopy.The operation time,blood loss,fluoroscopy times and postoperative hospital stay in the two groups were recorded.The VAS scores of shoulder joint pain and Neer score of shoulder joint function at 3 days after operation and the last follow-up were recorded.Results All patients received postoperative follow-up for nearly 6 months.The operation time of the two groups were(35.8±11.6)min and(50.1+15.5)min(t=3.303,P=0.002),the intraoperative blood loss were(38.4±9.3)ml and(60.3±10.2)ml(t=7.095,P=0.000), respectively,the fluoroscopy times of the two groups were(5.2±1.6)times and(9.7±2.1)times(t=7.622,P=0.000)respectively,the postoperative hospitalization stay were(6.7±0.5)d and(7±0.6)d(t=1.717,P=0.093),the differences were statistically different.The VAS scores of shoulder joint pain and Neer score of shoulder joint function at 3 days after operation and the last follow-up in both two groups were improved significantly than those in preoperative(P<0.05),while there were no significant differences in the two scores between the two groups(P>0.05).Conclusion 3D printing technique assisting minimally invasive surgery for displaced clavicle fractures in adults has the advantages of shorter operation time,less intraoperative blood loss and less fluoroscopy.The clinical follow-up Results are satisfactory.

Objective To explore the clinical application value of percutaneous kyphoplasty ( PKP ) under the guidance of G arm X ray machine in the treatment of osteoporotic vertebral compression fracture (OVCF). Methods The medical records of eighty-two patients (94 vertebral bodies) with OVCF treated with PKP were collected retrospectively. Thirty-nine cases ( 44 vertebral bodies ) were guided by G-arm X-ray machine to implement PKP,which were recorded as G-arm group. Forty-three cases (50 vertebral bodies) were guided by C-arm X-ray machine to carry out PKP,which were recorded as C-arm group. The operation time, intraoperative fluoroscopy times, bone cement leakage cases, preoperative and postoperative anterior height of injured vertebrae,Cobb angle of injured vertebrae,visual analogue scale scores and Oswestry disability index of the two groups were recorded. Results There was significant difference in operation time and intraoperative fluoroscopy times between the G-arm group and C-arm group (the operation time:(31. 6±5. 2) vs. (45. 8±6. 7) min,the intraoperative fluoroscopy times: (9. 5±2. 3) times vs. (18. 7±3. 5) times,t=-10. 64,-13. 91,P<0. 05) ,while there was no significant difference in the number of bone cement leakage ( P>0. 05) . Compared postoperative and preoperative anterior height of injured vertebrae, Cobb angle of injured vertebrae, visual analogue scale scores and Oswestry disability index scores of G-arm group and C-arm group respectively, the differences were significant ( t=-3. 41 vs. -3. 28, 6. 67 vs. 7. 66, 26. 63 vs. 25. 75 and 10. 41 vs. 11. 90, P<0. 05). There was no significant difference between the two groups (P>0. 05). Conclusion The treatment of OVCF with PKP guided by G-arm X-ray machine could significantly shorten operation time, reduce the intraoperative fluoroscopy times and the operative difficulty,and increase operation safety than PKP guided by traditional C-arm X-ray machine.

Objective To compare the clinical effects of G-arm X-ray machine and C-arm X-ray machine in percutaneous kyphoplasty (PKP) for osteoporotic vertebral compression fracture (OVCF) of thoracolumbar spine.Methods The clinical data of ninety-five patients with thoracolumbar OVCF treated with PKP from May 2016 to August 2017 in Yanan University Affiliated Hospital were retrospectively analyzed.They were divided into two groups according to the different guiding fluoroscopy methods used during the operation.Forty-six cases in G arm group completed PKP under the guidance of G arm X-ray machine,Forty-nine cases in C arm group completed PKP under the guidance of C arm X-ray machine.The operation time,fluoroscopy times,cement leakage cases,the height of injured vertebral leading edge,Cobb angle of kyphosis,visual analogue score and Oswestry dysfunction index were recorded before and after operation,and the related indexes were analyzed and compared.Results Two groups of patients were successfully completed surgery,no complications of vascular and nerve injury.The operation time and fluoroscopy times in G arm group were less than those in C arm group (operation time:(29.6±4.5) min vs.(42.5±5.3) min,and fluoroscopy times in G arm group:(9.1±2.0) vs.(16.9±3.2));the difference was statistically significant (t =-12.747,12.870,P＜ 0.01).Postoperative height of injured vertebral leading edge(G arm group (22.3±5.3) mm),C arm group (22.4±5.1) mm),kyphosis Cobb angle (G arm group (9.2±3.8)°,C arm group (9.3±3.7) o),visual analogue score (G arm group (2.1±0.7)points,C arm group (2.2±0.9) points),Oswestry dysfunction index (G arm group (21.3±8.5) points,C arm group(21.5 ± 8.3)points),compared with preoperative(the hight of injured vertebral leading edge of G arm group (18.2 ±5.3) mm,C arm group (18.4±5.2) mm,Cobb angle of injured vertebra G arm group (15.7±4.4) °,C arm group (15.9±4.3) °,visual analogue score of G arm group (7.8± 1.2) points,C arm group (7.7± 1.1) points,Oswestry dysfunction index score of G arm group(41.2±8.3)points,C arm group (41.5±8.2) points),the difference was statistically significant (t =-3.709,-3.844,-7.582,-8.144,27.827,27.088,11.360,11.999,P＜0.01),but there was no significant difference between the two groups (P ＞0.05).Conclusion Using G-arm X-ray machine to assist PKP in the treatment of thoracolumbar spine OVCF can effectively shorten the operation time,reduce the intraoperative fluoroscopy time,and the clinical effect is satisfactory.

Portal vein embolization （PVE） can induce atrophy of the embolized lobe and compensatory regeneration of the non-embolized lobe. However， due to inadequate regeneration of future liver remnant （FLR） after PVE， some patients remain unsuitable for hepatectomy after PVE. In recent years， liver venous deprivation （LVD）， which combines PVE with hepatic vein embolization （HVE）， has induced enhanced FLR regeneration. Compared with associating liver partition and portal vein ligation for staged hepatectomy （ALPPS）， LVD triggers faster and more robust FLR regeneration， with lower incidence rate of postoperative complications and mortality rate. By reviewing related articles on LVD， this article introduces the effectiveness of LVD and analyzes the differences and safety of various technical paths， and it is believed that LVD is a safe and effective preoperative pretreatment method.