Improved unilateral puncture PVP based on 3D printing technology for the treatment of osteoporotic vertebral compression fracture / 中国骨伤

OBJECTIVE@#To investigate the clinical effect of unilateral percutaneous vertebroplasty (PVP) combined with 3D printing technology for the treatment of thoracolumbar osteoporotic compression fracture.@*METHODS@#A total of 77 patients with thoracolumbar osteoporotic compression fractures from October 2020 to April 2022 were included in the study, all of which were vertebral body compression fractures caused by trauma. According to different treatment methods, they were divided into experimental group and control group. Thirty-two patients used 3D printing technology to improve unilateral transpedicle puncture vertebroplasty in the experimental group, there were 5 males and 27 females, aged from 63 to 91 years old with an average of (77.59±8.75) years old. Forty-five patients were treated with traditional bilateral pedicle puncture vertebroplasty, including 7 males and 38 females, aged from 60 to 88 years old with an average of(74.89±7.37) years old. Operation time, intraoperative C-arm X-ray times, anesthetic dosage, bone cement injection amount, bone cement diffusion good and good rate, complications, vertebral height, kyphotic angle (Cobb angle), visual analogue scale(VAS), Oswestry disability index (ODI) and other indicators were recorded before and after surgery, and statistically analyzed.@*RESULTS@#All patients were followed up for 6 to 23 months, with preoperative imaging studies, confirmed for thoracolumbar osteoporosis compression fractures, two groups of patients with postoperative complications, no special two groups of patients' age, gender, body mass index (BMI), time were injured, the injured vertebral distribution had no statistical difference(P>0.05), comparable data. Two groups of patients with bone cement injection, bone cement dispersion rate, preoperative and postoperative vertebral body height, protruding after spine angle(Cobb angle), VAS, ODI had no statistical difference(P>0.05). The operative time, intraoperative fluoroscopy times and anesthetic dosage were statistically different between the two groups(P<0.05). Compared with the traditional bilateral puncture group, the modified unilateral puncture group combined with 3D printing technology had shorter operation time, fewer intraoperative fluoroscopy times and less anesthetic dosage. The height of anterior vertebral edge, kyphosis angle (Cobb angle), VAS score and ODI of the affected vertebrae were statistically different between two groups at each time point after surgery(P<0.05).@*CONCLUSION@#In the treatment of thoracolumbar osteoporotic compression fractures, 3D printing technology is used to improve unilateral puncture PVP, which is convenient and simple, less trauma, short operation time, fewer fluoroscopy times, satisfactory distribution of bone cement, vertebral height recovery and kyphotic Angle correction, and good functional improvement.

Development and clinical application of a new transverse process retractor based on computer-aided design and 3D printing technology / 中国骨伤

OBJECTIVE@#To manufacture a new type of transverse process retractor by using computer-aided design(CAD) combined with 3D printing technology and investigate its clinical application effect.@*METHODS@#A new type of transverse protrusion retractor was developed by CAD combined with 3D printing technology. From September 2018 to September 2019, the new transverse process retractor was applied in clinic. Sixty patients with lumbar single segment lesions who needed treatment by pedicle screw fixation, bone grafting and interbody fusion were divided into new transverse process retractor group and control group, with 30 cases in each group. There were 14 males and 16 females in new type transverse process retractor group, the age was (68.0±4.3) years old on average; lesion segment of 8 cases were L3,4, 9 cases were L4,5, 13 cases were L5S1;5 cases of lumbar disc herniation, 20 cases of lumbar spinal stenosis, 5 cases of degenerative lumbar spondylolisthesis;new transverse process retractor was used to pedicle screw placement. While there were 15 males and 15 females in control group, with an average age of (69.2±4.5) years old;lesion segment of 8 cases were L3,4, 10 cases were L4,5, 12 cases were L5S1;5 cases of lumbar disc herniation, 21 cases of lumbar spinal stenosis, 4 cases of degenerative lumbar spondylolisthesis;the traditional lamina retractor was used for soft tissue pulling and finished pedicle screw placement by freehand. The length of surgical incision, the time required for inserting a single screw, fluoroscopy times, the times of adjusting the positioning needle or screw in insertion process, and the visual analogue scale (VAS) of surgical incision 72 hours after operation were compared between two groups.@*RESULTS@#Using CAD and 3D printing technology, a new type of transverse protrusion retractor was developed quickly. The length of surgical incision, the time required for inserting a single screw, fluoroscopy time, and the times of adjusting the positioning needle or screw in insertion process in new transverse process retractor group were less than those in control group(P<0.05). There was no significant difference in VAS of lumbar incision pain at 72 hours after operation between two groups(P>0.05).@*CONCLUSION@#Using CAD combined with 3D printing technology to develop a new transverse protrusion retractor has the advantages of convenient design, short development cycle and low cost. It provides a new idea for the research and development of new medical devices. The new transverse process retractor has the advantages of easy operation, reliable fixation, less damage to paravertebral muscle, convenient pedicle screw placement, reducing fluoroscopy time and so on.

3D printing technology assisted the preoperative planning and application value in adult kyphoscoliosis deformity / 中国骨伤

OBJECTIVE@#To explore the application value of 3D printing technology in preoperative surgery plan and intraoperative auxiliary operation for adult kyphoscoliosis deformity.@*METHODS@#The clinical data of 12 adult patients with kyphoscoliosis deformity treated from September 2017 to January 2019 were retrospectively analyzed. There were 3 males and 9 females, aged from 21 to 63 years old with an average of (47.67±13.32) years old. Among them, 4 cases were congenital kyphoscoliosis, 2 cases were old tuberculosis thoracolumbar kyphosis ; 2 cases were idiopathic kyphoscoliosis, 4 cases were degenerative kyphoscoliosis. The CT scan data of the patient's spine was imported into Mimics17.0 software to establish the three dimensional model of the spine, and the spine model was produced by 3D printer. Using the spine model simulated operation, preoperative surgery program planning and formulated a precise surgery, and further analysed postoperative imaging parameters improvement. All the patients were followed up for more than 1 year. Before and after operation and at the last follow-up, the scoliosis Cobb angle, maximum kyphosis Cobb angle, and coronal plane balance (distance between C 7 plumbline and center sacral vertical line, CPL-CSVL), sagittal plane balance (sagittal vertical axis, SVA), pelvic parameters and other related imaging parameters were measured to further evaluate its orthopedic effect.@*RESULTS@#Twelve patients with spine deformity were treated with different osteotomy and internal fixation fusion methods under the guidance of a 1∶1 spine model (pedicle screw placement of 4 patients with severe deformity were assisted by pedicle screw guide plates), nail placement and osteotomy have good effects, no major tissue damage such as blood vessels, nerves and spinal cord during and after surgery, no complications such as cerebrospinal fluid leakage and infection. Preoperative Cobb angle of scoliosis was (56.5±22.5) °, Cobb angle of kyphosis was (65.2±19.5) °, C PL-CSVL was (45.8±16.9) mm, SVA was (48.7±25.4) mm. Postoperative at 4 weeks, Cobb angle of scoliosis was (20.8±11.5) °, and Cobb angle of kyphosis was (22.0±6.6) °, with correction rates of (65.1±9.7)% and (64.6± 10.6)%, respectively ; C PL-CSVL was (22.3±8.9) mm, and SVA was (23.3±13.1) mm, all of which were significantly improved compared with preoperative results. The mean follow-up time was (18.5±7.9) months in 12 patients. At the last follow-up, the Cobb angles of scoliosis and kyphosis were (22.2±10.8) ° and (23.6±7.7) °, respectively, C PL-CSVL was (23.5±10.8) mm, and SVA was (24.7±12.5) mm. The results were statistically significant compared preoperative (0.05).@*CONCLUSION@#The 3D print model can visually and clearly show the vertebral morphology and structure of adult kyphoscolisis and its spatial relationship with the adjacent vertebrae, blood vessels, and nerves, which provides a good and intuitive stereoscopic anatomical structure observation for the individualization of the surgical plan. Pre-simulation of operations to determine the internal fixation, fusion segment and osteotomy orthopedic way, may to provide a reference for actual clinical surgery, and can improve the accuracy and safety of surgery.