Percutaneous internal fixation with the monoplanar pedicle screws in the treatment of multilevel thoracolumbar fractures: a case series of 6 cases

Percutaneous internal fixation with the monoplanar pedicle screws in the treatment of multilevel thoracolumbar fractures: a case series of 6 cases | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Help Center Sign In Submit a Preprint Cite Share Download PDF Article Percutaneous internal fixation with the monoplanar pedicle screws in the treatment of multilevel thoracolumbar fractures: a case series of 6 cases Xianglong Li, Yongfeng Zhang, Hao Liu, Shuang Xu, Lidong Li, Beiyu Chen, and 2 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-4696595/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Fixed-axis screw and polyaxial screw exposed many disadvantages in the treatment of multiple thoracolumbar fractures. This is the first report on the treatment of multiple thoracolumbar fractures with percutaneous axial monoplanar pedicle screw. Six patients with multiple vertebral fractures were treated with monoplanar pedicle screw implantation and distraction reduction under general anesthesia. The height correction of injured vertebrae, T11-L2 kyphosis angle, Visual Analogue Scale (VAS) and Oswestry Disability Index (ODI) scores were measured before and after operation to evaluate the effectiveness of surgical treatment. All patients underwent smooth surgery, with an average operation time of 117.5 minutes and an average intraoperative blood loss of 71.7 ml. All patients were able to walk with the aid of a waist brace on the 3rd postoperative day and discharged on the 4th postoperative day. Low back pain symptoms were significantly relieved after operation. VAS score, ODI dysfunction index, the height correction of injured vertebrae, T11-L2 kyphosis angle and LL were all satisfactorily corrected immediately after surgery, and satisfactory results were maintained at 6 and 12 months after surgery. All patients received minimally invasive removal of internal fixation at the original surgical incision during 12–14 months after surgery, and the injured vertebrae were well reduced without significant height loss of the injured vertebrae. The use of percutaneous monoplanar pedicle screws for the treatment of multiple thoracolumbar fractures is a minimally invasive technique with satisfactory long-term reduction effect. Health sciences/Diseases/Trauma Health sciences/Health care/Fracture repair multilevel thoracolumbar fractures percutaneous internal fixation minimally invasive monoplanar pedicle screw Figures Figure 1 Figure 2 Figure 3 Figure 4 INTRODUCTION The continuous or discontinuous multiple fractures of thoracolumbar segment are relatively rare types of spinal fractures, mostly caused by violent external forces. The reported morbidity varies greatly, accounting for 1.6%-23.8% of spinal fractures 1–3 . There is currently no optimal treatment for this fracture. Although percutaneous kyphoplasty (PKP) or percutaneous vertebroplasty (PVP) can relieve pain in the early stage of surgery 4,5 and restore quality of life, multi-segment bone cement injection will increase the risk of fracture in adjacent segments in the future, and this non-biological healing method is especially not suitable for young and middle-aged patients. Traditional open surgery is also commonly considered options, but extensive dissection of soft tissue inevitably results in extensive scarring of muscle tissue. 6 By contrast, with the percutaneous pedicle screw technique, only blunt separation through the muscle space is required to complete the screw placement, which can reduce soft tissue injury and achieve a certain reduction effect. However, the traditional pedicle screws in the treatment of multiple vertebral fractures are limited by such factors as limited reduction ability, the loss of the correction height and difficulty of implanting the rod. Monoplanar percutaneous pedicle screw is a new minimally invasive vertebral fracture treatment system that our team has participated in the design and development. This system has been successfully applied in the surgical treatment of single vertebral compression fracture by our team in the early stage, achieving satisfactory reduction and long-term efficacy. 7, 8 However, this system has not been attempted for multilevel thoracolumbar fractures. The present study is the first to report 6 cases of multilevel thoracolumbar vertebral fractures (total 14 fracture vertebras) treated with monoplanar pedicle screws. The patients were followed up at 3 days, 6 months, and 12 months after surgery, and the follow-up imaging results and functional scores were analyzed. MATERIALS AND METHODS Patient Selection 6 patients with multiple thoracolumbar fractures in authors’ spine center from 2019 to 2021 were retrospectively analyzed. Criteria for inclusion: ( 1 ) Spinal fractures caused by trauma in patients aged 18–60 years; ( 2 ) Imaging suggested multilevel thoracolumbar fractures; ( 3 ) Fracture time was less than one week. Exclusion criteria : ( 1 ) Patients with neurological impairment requiring open surgery for spinal decompression;( 2 ) Patients with severe osteoporosis with bone mineral density (BMD) T≤ -3.5; ( 3 ) Patients whose condition is too serious to receive surgical treatment; ( 4 ) patients complicated with other organ injuries; ( 5 ) Patients with pathological fracture. According to the imaging examination results at admission, the 6 patients had a total of 14 injured vertebra, and the AO classification of fracture was all Type A (6 vertebras were A1, 8 vertebras were A3). According to the TLICS score: 5 vertebras' score was ≤ 3, 4 vertebras' score was 4, 5 vertebras' score was ≥ 5 (Fig. 1 ). This is a retrospective study, and the informed consent waiver for the whole study was granted by Ethics Committee of Xijing Hospital (The Fourth Military Medical University, Xi’an, Shaanxi Province, China). In addition, all cases in this study were clinically treated according to the internationally accepted AO classification and TLICS spinal fracture scoring principles Clinical data collection All patients underwent anteroposterior and lateral lumbar X-ray, lumbar CT scan and three-dimensional reconstruction, lumbar MRI examination, bone mineral density detection, and measurement of the pedicle width of the vertebral body requiring screw placement upon admission. Routine preoperative examination was performed to exclude surgical contraindications. Operative time, intraoperative blood loss and hospital stays were collected. VAS score and ODI dysfunction index were followed up before and after surgery (3 days, 6 months and 12 months) to evaluate the efficacy of the patients. 9 Relevant clinical data were collected and analyzed according to the examination of X ray, including kyphosis of T11-L2, lumbar lordosis (LL) and the percentage of the vertebral body height (VBH). 1, 10–12 VBH = A / [(B + C)/2 ] x 100%. A, the height of anterior edge of injured vertebra; B, the anterior edge height of the upper vertebral body of the injured vertebra (in discontinuous segmental fractures) or the anterior edge height of the adjacent normal vertebral body at the headend of the fractured segment (in continuous segmental fractures); C, the anterior edge height of the lower vertebral body of the injured vertebra (in discontinuous segmental fractures) or the anterior edge height of the adjacent normal vertebra at the distal end of the fractured segment (in continuous segmental fractures). Statistical analysis SPSS Statistics software version 23 was used for statistical analysis of the data. The continuous variable data were expressed as means ± standard deviation, and repeated measure analysis of variance was adopted. P < 0.05 was considered statistically significant. Surgical procedure In this study, the fractured vertebral bodies of the 6 patients were all concentrated in the range of L1-4, hence the internal fixation segments were all within the range of T12-L5. A patient with compression fractures of L1 and L3 vertebral bodies (Fig. 2 A, B, C) required for percutaneous reduction of L1 and L3 was taken as an example to describe the surgical procedures: firstly, after general anesthesia, the patient was in prone position with the abdomen suspended, and postural reduction was carried out through weight and appropriate back spine press. Secondly, the patient's position was adjusted so that the vertebral body of the surgical segment was in the standard anteroposterior position in X-ray fluoroscopy. 13 The pedicle projection was marked on the body surface according to the X-ray fluoroscopy and routine disinfection was performed. Thirdly, According to the conventional percutaneous pedicle screw placement method, 13 bilateral monoplannar pedicle screw placement of T12, L2 and L4 was completed under C-arm guidance. The extension arm of the screw tail remains in place (Fig. 2 D). The movement direction of the screw tail was adjusted to keep in the axial plane by rotating the extension arm. Fourthly, The two titanium rods were prebent to an appropriate radian in vitro according to preoperative measurement of patient’s pelvic incidence (PI) value, then passed through the Wiltse muscle spatial and placed in the extension arm of the bilateral screw tail in sequence. While the titanium rod was pressed into the screw tail with a rotary press, all nuts were screwed into the screw tails (didn't lock), and the radian of the titanium rod was used to restore the lumbar lordosis preliminarily (Fig. 2 E). Fifthly, the nut of L4 was locked on one side, and the distraction forceps was placed between L4 and L2 screw tail extension arms (Fig. 2 F) to reduce L3 vertebral body with appropriate force, then the nut of ipsilateral L2 was locked. The distraction forceps was then placed between the T12 and L2 screw tail extension arm to reduced L1 vertebral body, and the T12 nut was locked. The distraction reduction was performed on the opposite side in the same way, and the nuts were locked. After the C-arm fluoroscopy confirmed satisfactory reduction of the fractured vertebral body and good internal fixation position, the screw tail extension arms were removed, and the wound was closed. Postoperative routine prevention of infection, analgesia and anti-osteoporosis treatment were performed. RESULTS A total of 6 eligible patients were included in this study, including 4 males and 2 females, with an average age of 43 years (rang, 23–58 years), an average time from injury to surgery of 4 days (rang, 1–7 days), an average operation time of 117.5 minutes, and an average intraoperative blood loss of 71.7ml. All patients were hospitalized for 5 days, and all patients were able to walk with the assistance of a lumbar brace on the third day after surgery. All patients wore a thoracolumbar brace for 3 months after surgery. The mean follow-up time was 13.3 months (rang, 12–14 months). All patients showed significant improvement in postoperative pain symptoms, with VAS scores of 6.3 points, 3 points, 0.2 points and 0.2 points before surgery, 3 days after surgery, 6 months after surgery and 12 months after surgery, respectively. The daily living ability was significantly improved. The mean value of ODI dysfunction index was 93.8% before surgery, 76.5% 3 days after surgery, 21.3% 6 months after surgery, and 6.2% 12 months after surgery. The ODI value decreased significantly after surgery. The clinical outcomes are summarized in Table 1 . Table 1 The parameters of patients before and after operation Case 1 Case 2 Case 3 Case 4 Case 5 Case 6 Mean Operation time (min) 110 120 110 100 135 130 117.5 Blood loss (ml) 50 50 80 100 50 100 71.7 Hospital stay (days) 5 5 5 5 5 5 5.0 VAS Pre-operation 7 7 6 6 7 5 6.3 3 day post-op. 3 4 3 3 3 2 3.0 6 months post-op. 1 0 0 0 0 0 0.2 12 months post-op. 0 0 0 1 0 0 0.2 ODI (%) Pre-operation 98 94 93 91 91 96 93.8 3 day post-op. 70 68 76 78 87 80 76.5 6 months post-op. 22 18 16 20 25 27 21.3 12 months post-op. 8 6 0 7 7 9 6.2 Kyphosis (T11 - L2) Pre-operation 18° 12° 11° 13 9° 16° 13.2° 3 day post-op. 1° 3° 3° 0° 0° 2° 1.5° 6 months post-op. 0° 2° 1° 1° 0° 2° 1.0° 12 months post-op. 1° 0° 0° 4° 0° 4° 1.5° LL Pre-operation 21° 31° 29° 39° 41° 39° 33.3° 3 days post-op. 43° 51° 39° 43° 40° 49° 44.2° 6 months post-op. 45° 56° 28° 45° 48° 52° 45.7° 12 months post-op. 46° 54° 37° 44° 49° 48° 46.3° ODI, Oswestry Disability Index. The postoperation X-ray showed significant reduction of all injured vertebrae (Fig. 3 ). The average VBH of 14 injured vertebrae before surgery was 79.0%, and the VBH at 3 days, 6 months and 12 months after surgery was 95.6%, 93.3% and 93.1%, respectively (Fig. 4 ). Among them, the VBH of three injured vertebrae reached more than 97% after reduction, and the VBH of the one injured vertebrae with the worst reduction recovered to 85.0%. Compared with 3 days after surgery, the reduction height of injured vertebrae lost 2.5% on average at 12 months after surgery. Six patients had varied degrees of T11-L2 kyphosis before surgery. Kyphosis angle averaged 13.2° (rang, 9° -18 °), which decreased to 1.5° three days after surgery, 1.0° six months after surgery, and 1.5° twelve months after surgery. The reconstruction of lumbar lordosis angle was satisfied in 6 patients, the mean value of LL before surgery was 33.3°, which increased to 44.2° three days after surgery, 45.7° six months after surgery, and 46.3° twelve months after surgery. All the patients were re-examined during 12–14 months after surgery, and the fracture recovered well without fracture or loosening of internal fixation, and the internal fixation were removed in the 6 patients. The clinical outcomes are summarized in Table 1 . DISCUSSION Multilevel thoracolumbar fractures are usually caused by high-energy injuries, and the number of fractured vertebrae is ≥ 2, which presents new challenges for traditional surgical methods and internal fixation instruments. Traditional open surgery, with the long surgical incision and heavy damage, usually cause intractable back pain because that the paraspinal muscles are stripped twice in the process of implantation and removal of internal fixation. 14 Percutaneous minimally invasive internal fixation has the advantages of smaller trauma and faster healing. 11, 15 In 1982, Margrel reported the treatment of spinal fractures with percutaneous fixed-axis pedicle screws, providing a minimally invasive and effective treatment for biological healing of spinal fractures. 16 However, existing methods for the treatment of multiple thoracolumbar fractures face substantial difficulties, due to the difficulty of setting the rod with fixed-axial screw and the reduction height loss with the multi-axial screw. 11, 17 The monoplanar pedicle screw is based on the fixed-axial screw, and the screw tail is limited to swing only in the axial plane, so it has the following advantages: 1.The screw tail can swing in the axial plane, which overcomes the disadvantage of the titanium rod implantation difficulty of the fixed-axis screw. 2. The tail of the screw has no moving angle in the sagittal plane, which overcomes the disadvantage of the poor reduction effect of multi-axis screw in sagittal position. The height loss rate of vertebral body was lower than that of multi-axial screw. 3. The arc of rod can be used to recover the height of the injured vertebra by locking the screw cap because of no swing angle in the sagittal plane. For patients with multiple thoracolumbar fractures, the main objectives of surgery are to recover the injured vertebra height as far as possible, restore normal lumbar lordosis and correct thoracolumbar kyphosis. We used this set of tools for the reduction of injured vertebrae in three main steps: 1.The patient was placed in the prone position after general anesthesia, and the abdomen was suspended and pressed moderately to achieve preliminary reduction. Especially for the patients with osteoporosis, the reduction of the position can avoid the surgical risks such as the loosening of the nail path caused by the severe prying force of the surgical instrument. 2. Using a rotary press to force the titanium rod with prebent radian into the tail slot. Schwab et al. reported that the LL = PI ± 9°, 18, 19 and upper lumbar lordosis accounts for approximately 33% of the entire lumbar lordosis. 20, 21 Therefore, careful preoperative measurement of PI is required for different patients, and the curvature of the titanium rod is also depending on this parameter. In order to obtain better reduction effect and lumbar lordosis angle, the curvature of the rod can be increased by 0–10° on the basis of the calculated ideal angle. 17, 22 For patients with osteoporosis, there is no need to increase the curvature of the bending rod because of the pursuit of anatomical reduction of the vertebral body, so as not to cause loosening of the screw path. 3. If the height recovery of the injured vertebrae is still not satisfactory after the above two reduction procedures are completed, the final reduction of the injured vertebrae can be carried out using the distraction forceps. However, it is still recommended that the first two steps should be used for the reduction of injured vertebrae, and the force of prying should not be too large for the reduction of the third step, especially for patients with osteoporosis. In this report, all patients were successfully completed percutaneous titanium rod implantation with 3 groups of screws spanning 5 vertebral bodies. However, in our experience, rod placement is very difficult if the length exceeds 5 vertebras. In addition, there was no fracture of internal fixation in 6 patients during the whole follow-up period. We speculated that the use of screws with a diameter of 6.5 mm and rod with a diameter of 6.0 mm could meet the stress intensity requirements of this type of operation. More detailed biomechanical and stress analyses will be conducted in the future to further clarify the safety of this procedure. In conclusion, compared with open surgery, percutaneous screw fixation across the injured vertebrae has fewer traumas. The patients can moved to the ground 3 days after the operation, and has good reduction effect of the injured vertebrae, which can significantly reduce the occurrence of thoracolumbar kyphosis and prevent back pain in the later stage. This also makes patients with TLICS score of 4–5 be confident to choose surgical treatment, avoid long-term bed immobility, long-term separation from society and work. Therefore, monoplanar pedicle screws have a good prospect in the treatment of multiple thoracolumbar fractures. CONCLUSION The use of percutaneous monoplanar pedicle screws is a minimally invasive technique, and overcome the disadvantages, loss of the correction height of the injured vertebra and difficulty of implanting the rod. It can be very useful for the treatment of multiple thoracolumbar fractures. Declarations CONFLICT OF INTEREST The authors have nothing to disclose. Author Contribution Xianglong Li and Yongfeng Zhang were responsible for this study design, surgical operation and manuscript writing. Hao Liu, Shuang Xu, Lidong Li and Beiyu Chen performed the data collecting, statistical analysis, patient follow-up. Zhe Wang and Tan Ding review the study proposal and fund this research. All authors read and approved the final manuscript. Acknowledgement No Data Availability The datasets used and/or analysed in this study are available from the corresponding authors upon reasonable request References Wang HW, Xiang Q, Li CQ, et al. Multiple-level noncontiguous spinal fractures: difference between the young and the elderly. J Spinal Disord Tech 2013;26: E272-E276. Korres DS, Boscainos PJ, Papagelopoulos PJ, et al. Multiple level noncontiguous fractures of the spine. Clin Orthop Relat Res 2003;411:95–102. Takami M, Okada M, Enyo Y, et al. Noncontiguous double-level unstable spinal injuries. Eur J Orthop Surg Traumatol 2017;27:79–86. Jaffray DC, Eisenstein SM, Balain B, et al. Early mobilisation of thoracolumbar burst fractures without neurology: a natural history observation. Bone Joint J 2016;98-B: 97–101. Wittenberg RH, Hargus S, Steffen R, et al. Noncontiguous unstable spine fractures. Spine (Phila Pa 1976) 2002;27: 254–7. Sharif S, Shaikh Y, Yaman O, et al. Surgical Techniques for Thoracolumbar Spine Fractures: WFNS Spine Committee Recommendations. Neurospine 2021; 18: 667–80. Ye B, Yan M, Zhu HY, et al. Novel Screw Head Design of Pedicle Screw for Reducing the Correction Loss in the Patients With Thoracolumbar Vertebral Fractures. Spine (Phila Pa 1976) 2017;42:E379-E384. Zhang SL, Yan M, Ding ZY, et al. Effect of indirect decompression with minimally invasive percutaneous uniplanar pedicle screw on canal encroachment rate and vertebral height in thoracolmbar fracture. 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Acta Neurochir (Wien) 2015;157:831–6. Pannu CD, Farooque K, Sharma V, et al. Minimally invasive spine surgeries for treatment of thoracolumbar fractures of spine: A systematic review. J Clin Orthop Trauma 2019;10(Suppl 1):S147-S155. Magerl FP. External Skeletal Fixation of the Lower Thoracic and the Lumbar Spine. Clin Orthop Relat Res 1984;189:125–41. Ni WF, Huang YX, Chi YL, et al. Percutaneous pedicle screw fixation for neurologic intact thoracolumbar burst fractures. J Spinal Disord Tech 2010;23:530–7. Schwab F, Lafage V, Patel A, et al. Sagittal Plane Considerations and the Pelvis in the Adult Patient. Spine (Phila Pa 1976) 2009;34:1828–33. Savarese LG, Menezes-Reis R, Bonugli GP, et al. Spinopelvic sagittal balance: what does the radiologist need to know? Radiol Bras 2020;53:175–84. Guo JM, A.Li MJ. Relationship between Low Back Pain and Lumbar Lordosis and Sacral Inclination in Adult People. Journal of practical orthopaedics 2007;13: 577–9. Nakipoğlu GF, Karagöz A, Ozgirgin N. The Biomechanics of the Lumbosacral Region In Acute And Chronic Low Back Pain Patients. Pain Physician 2008; 11: 505–11. Yang M, Zhao QP, Hao DJ, et al. Comparison of clinical results between novel percutaneous pedicle screw and traditional open pedicle screw fixation for thoracolumbar fractures without neurological deficit. Int Orthop 2019;43:1749–54. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. 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Also discoverable on Platform About Our Team In Review Editorial Policies Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-4696595","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":344889033,"identity":"3304db4a-3219-4c59-81ba-357989038d26","order_by":0,"name":"Xianglong Li","email":"","orcid":"","institution":"the Second Affiliated Hospital of Xi’an Medical University","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Xianglong","middleName":"","lastName":"Li","suffix":""},{"id":344889034,"identity":"c7cb09ff-61a0-470a-943b-8943bfa0c01b","order_by":1,"name":"Yongfeng Zhang","email":"","orcid":"","institution":"Xijing Hospital","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Yongfeng","middleName":"","lastName":"Zhang","suffix":""},{"id":344889035,"identity":"2133d977-97dd-47bc-93ac-16ef0f5370cc","order_by":2,"name":"Hao Liu","email":"","orcid":"","institution":"PLA Lushan Rehabilitation and Recuperation Center","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Hao","middleName":"","lastName":"Liu","suffix":""},{"id":344889036,"identity":"fe1c4a99-90f2-4abc-9354-bbbd34a83037","order_by":3,"name":"Shuang Xu","email":"","orcid":"","institution":"Affiliated Hospital of Southwest Medical University","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Shuang","middleName":"","lastName":"Xu","suffix":""},{"id":344889037,"identity":"5698903e-68ed-4163-ae6a-86079fb00102","order_by":4,"name":"Lidong Li","email":"","orcid":"","institution":"Affiliated Hospital of Southwest Medical University","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Lidong","middleName":"","lastName":"Li","suffix":""},{"id":344889038,"identity":"a685dc2e-1a49-4426-a4dd-3e0dbf03a76d","order_by":5,"name":"Beiyu Chen","email":"","orcid":"","institution":"Xijing Hospital","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Beiyu","middleName":"","lastName":"Chen","suffix":""},{"id":344889039,"identity":"d083368b-4091-40b1-8be7-82c779ab9a34","order_by":6,"name":"Zhe Wang","email":"","orcid":"","institution":"Xijing Hospital","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Zhe","middleName":"","lastName":"Wang","suffix":""},{"id":344889041,"identity":"be3bbfce-7e68-4ff2-840a-1cd6013ffc17","order_by":7,"name":"Tan Ding","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAvklEQVRIiWNgGAWjYDCCAwwGDAwVchAOD1FajoG0nDEmVQtjGyla+O43b5PmnWcQrTsjgfHB2zYGeXNCWiSPsZVJ824zyN12I4HZcG4bg+HOBgJaDI7xmAG1/AFpYZPmbWNIMDhAlJY5YFvYf5OgpQGshY2ZKC2Sx9KKLeccA2o587BZcs45CcMNhLTwHT688cabGqCW48kHP7wps5EnaAsQsEhBooOxAUhIEFYPBMwffxClbhSMglEwCkYsAADstkFwyJ4NzwAAAABJRU5ErkJggg==","orcid":"","institution":"Xijing Hospital","correspondingAuthor":true,"submittingAuthor":false,"prefix":"","firstName":"Tan","middleName":"","lastName":"Ding","suffix":""}],"badges":[],"createdAt":"2024-07-06 11:44:43","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-4696595/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-4696595/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":64388034,"identity":"6ede6ad4-a07b-4efa-925f-4e1b51d176a5","added_by":"auto","created_at":"2024-09-12 12:44:43","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":844036,"visible":true,"origin":"","legend":"\u003cp\u003ePreoperative MRI and X-ray of the patient. A total of 14 vertebral fractures were found in 6 patients, with the fracture sites indicated by arrows in the order A-F.\u003c/p\u003e","description":"","filename":"image1.png","url":"https://assets-eu.researchsquare.com/files/rs-4696595/v1/c3345b3a30e243cdcdaabe4a.png"},{"id":64386480,"identity":"151ae8b1-30ad-445c-9b1e-896a6df66957","added_by":"auto","created_at":"2024-09-12 12:36:44","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":1075221,"visible":true,"origin":"","legend":"\u003cp\u003ePreoperative imaging and intraoperative procedures. Preoperative imaging (A-C); The extension arm of the screw tail remains in place (D); the screw tail has no swing angle in the sagittal plane, so the angle δ is always 90° (E); the reduction was performed by distraction forceps (F).\u003c/p\u003e","description":"","filename":"image2.png","url":"https://assets-eu.researchsquare.com/files/rs-4696595/v1/9e03b877bcf283b208063f17.png"},{"id":64386477,"identity":"ddcf763c-3191-4c48-91d7-beed614d3466","added_by":"auto","created_at":"2024-09-12 12:36:43","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":926897,"visible":true,"origin":"","legend":"\u003cp\u003eTaking one of the patients for example, X-ray showed height variations of the injured vertebrae before and 12 months after operation.\u003c/p\u003e","description":"","filename":"image3.png","url":"https://assets-eu.researchsquare.com/files/rs-4696595/v1/c3f159d002a8734b40a223cf.png"},{"id":64386479,"identity":"e3770c00-3452-44aa-96fe-be4d68717ab7","added_by":"auto","created_at":"2024-09-12 12:36:44","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":573284,"visible":true,"origin":"","legend":"\u003cp\u003e(A-F) X-ray showed satisfactory reduction of the fractured vertebral body in 6 patients, kyphosis of the thoracolumbar junction disappeared, and LL recovered well 12-14 months after operation (corresponding to A-F in Fig. 1). (G)The height variations of 14 fractured vertebras before and after surgery in this study. The value is expressed as Means ± SD. *Indicates \u003cem\u003eP\u003c/em\u003e \u0026lt; 0.05 when compared with pre-operation.\u003c/p\u003e","description":"","filename":"image4.png","url":"https://assets-eu.researchsquare.com/files/rs-4696595/v1/39bc6cf9b3a21313d0f42bc4.png"},{"id":90764762,"identity":"901fcbee-b144-4316-bab7-269ea58c0002","added_by":"auto","created_at":"2025-09-07 17:46:34","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":4919182,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-4696595/v1/7e373b7a-2be2-4a18-91da-4fc96bb7103e.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Percutaneous internal fixation with the monoplanar pedicle screws in the treatment of multilevel thoracolumbar fractures: a case series of 6 cases","fulltext":[{"header":"INTRODUCTION","content":"\u003cp\u003eThe continuous or discontinuous multiple fractures of thoracolumbar segment are relatively rare types of spinal fractures, mostly caused by violent external forces. The reported morbidity varies greatly, accounting for 1.6%-23.8% of spinal fractures\u003csup\u003e1\u0026ndash;3\u003c/sup\u003e. There is currently no optimal treatment for this fracture. Although percutaneous kyphoplasty (PKP) or percutaneous vertebroplasty (PVP) can relieve pain in the early stage of surgery \u003csup\u003e4,5\u003c/sup\u003e and restore quality of life, multi-segment bone cement injection will increase the risk of fracture in adjacent segments in the future, and this non-biological healing method is especially not suitable for young and middle-aged patients. Traditional open surgery is also commonly considered options, but extensive dissection of soft tissue inevitably results in extensive scarring of muscle tissue.\u003csup\u003e6\u003c/sup\u003e By contrast, with the percutaneous pedicle screw technique, only blunt separation through the muscle space is required to complete the screw placement, which can reduce soft tissue injury and achieve a certain reduction effect. However, the traditional pedicle screws in the treatment of multiple vertebral fractures are limited by such factors as limited reduction ability, the loss of the correction height and difficulty of implanting the rod.\u003c/p\u003e \u003cp\u003e Monoplanar percutaneous pedicle screw is a new minimally invasive vertebral fracture treatment system that our team has participated in the design and development. This system has been successfully applied in the surgical treatment of single vertebral compression fracture by our team in the early stage, achieving satisfactory reduction and long-term efficacy.\u003csup\u003e7, 8\u003c/sup\u003e However, this system has not been attempted for multilevel thoracolumbar fractures. The present study is the first to report 6 cases of multilevel thoracolumbar vertebral fractures (total 14 fracture vertebras) treated with monoplanar pedicle screws. The patients were followed up at 3 days, 6 months, and 12 months after surgery, and the follow-up imaging results and functional scores were analyzed.\u003c/p\u003e"},{"header":"MATERIALS AND METHODS","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003ePatient Selection\u003c/h2\u003e \u003cp\u003e6 patients with multiple thoracolumbar fractures in authors\u0026rsquo; spine center from 2019 to 2021 were retrospectively analyzed. Criteria for inclusion: (\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e) Spinal fractures caused by trauma in patients aged 18\u0026ndash;60 years; (\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e) Imaging suggested multilevel thoracolumbar fractures; (\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e) Fracture time was less than one week. Exclusion criteria : (\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e) Patients with neurological impairment requiring open surgery for spinal decompression;(\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e) Patients with severe osteoporosis with bone mineral density (BMD) T\u0026le; -3.5; (\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e) Patients whose condition is too serious to receive surgical treatment; (\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e) patients complicated with other organ injuries; (\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e) Patients with pathological fracture. According to the imaging examination results at admission, the 6 patients had a total of 14 injured vertebra, and the AO classification of fracture was all Type A (6 vertebras were A1, 8 vertebras were A3). According to the TLICS score: 5 vertebras' score was \u0026le;\u0026thinsp;3, 4 vertebras' score was 4, 5 vertebras' score was \u0026ge;\u0026thinsp;5 (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). This is a retrospective study, and the informed consent waiver for the whole study was granted by Ethics Committee of Xijing Hospital (The Fourth Military Medical University, Xi\u0026rsquo;an, Shaanxi Province, China). In addition, all cases in this study were clinically treated according to the internationally accepted AO classification and TLICS spinal fracture scoring principles\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec4\" class=\"Section2\"\u003e \u003ch2\u003eClinical data collection\u003c/h2\u003e \u003cp\u003eAll patients underwent anteroposterior and lateral lumbar X-ray, lumbar CT scan and three-dimensional reconstruction, lumbar MRI examination, bone mineral density detection, and measurement of the pedicle width of the vertebral body requiring screw placement upon admission. Routine preoperative examination was performed to exclude surgical contraindications.\u003c/p\u003e \u003cp\u003eOperative time, intraoperative blood loss and hospital stays were collected. VAS score and ODI dysfunction index were followed up before and after surgery (3 days, 6 months and 12 months) to evaluate the efficacy of the patients.\u003csup\u003e9\u003c/sup\u003e Relevant clinical data were collected and analyzed according to the examination of X ray, including kyphosis of T11-L2, lumbar lordosis (LL) and the percentage of the vertebral body height (VBH). \u003csup\u003e1, 10\u0026ndash;12\u003c/sup\u003e VBH\u0026thinsp;=\u0026thinsp;A / [(B\u0026thinsp;+\u0026thinsp;C)/2 ] x 100%. A, the height of anterior edge of injured vertebra; B, the anterior edge height of the upper vertebral body of the injured vertebra (in discontinuous segmental fractures) or the anterior edge height of the adjacent normal vertebral body at the headend of the fractured segment (in continuous segmental fractures); C, the anterior edge height of the lower vertebral body of the injured vertebra (in discontinuous segmental fractures) or the anterior edge height of the adjacent normal vertebra at the distal end of the fractured segment (in continuous segmental fractures).\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec5\" class=\"Section2\"\u003e \u003ch2\u003eStatistical analysis\u003c/h2\u003e \u003cp\u003eSPSS Statistics software version 23 was used for statistical analysis of the data. The continuous variable data were expressed as means\u0026thinsp;\u0026plusmn;\u0026thinsp;standard deviation, and repeated measure analysis of variance was adopted. P\u0026thinsp;\u0026lt;\u0026thinsp;0.05 was considered statistically significant.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec6\" class=\"Section2\"\u003e \u003ch2\u003eSurgical procedure\u003c/h2\u003e \u003cp\u003eIn this study, the fractured vertebral bodies of the 6 patients were all concentrated in the range of L1-4, hence the internal fixation segments were all within the range of T12-L5. A patient with compression fractures of L1 and L3 vertebral bodies (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eA, B, C) required for percutaneous reduction of L1 and L3 was taken as an example to describe the surgical procedures: firstly, after general anesthesia, the patient was in prone position with the abdomen suspended, and postural reduction was carried out through weight and appropriate back spine press. Secondly, the patient's position was adjusted so that the vertebral body of the surgical segment was in the standard anteroposterior position in X-ray fluoroscopy.\u003csup\u003e13\u003c/sup\u003e The pedicle projection was marked on the body surface according to the X-ray fluoroscopy and routine disinfection was performed. Thirdly, According to the conventional percutaneous pedicle screw placement method,\u003csup\u003e13\u003c/sup\u003e bilateral monoplannar pedicle screw placement of T12, L2 and L4 was completed under C-arm guidance. The extension arm of the screw tail remains in place (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eD). The movement direction of the screw tail was adjusted to keep in the axial plane by rotating the extension arm. Fourthly, The two titanium rods were prebent to an appropriate radian in vitro according to preoperative measurement of patient\u0026rsquo;s pelvic incidence (PI) value, then passed through the Wiltse muscle spatial and placed in the extension arm of the bilateral screw tail in sequence. While the titanium rod was pressed into the screw tail with a rotary press, all nuts were screwed into the screw tails (didn't lock), and the radian of the titanium rod was used to restore the lumbar lordosis preliminarily (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eE). Fifthly, the nut of L4 was locked on one side, and the distraction forceps was placed between L4 and L2 screw tail extension arms (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eF) to reduce L3 vertebral body with appropriate force, then the nut of ipsilateral L2 was locked. The distraction forceps was then placed between the T12 and L2 screw tail extension arm to reduced L1 vertebral body, and the T12 nut was locked. The distraction reduction was performed on the opposite side in the same way, and the nuts were locked. After the C-arm fluoroscopy confirmed satisfactory reduction of the fractured vertebral body and good internal fixation position, the screw tail extension arms were removed, and the wound was closed. Postoperative routine prevention of infection, analgesia and anti-osteoporosis treatment were performed.\u003c/p\u003e \u003c/div\u003e"},{"header":"RESULTS","content":"\u003cp\u003eA total of 6 eligible patients were included in this study, including 4 males and 2 females, with an average age of 43 years (rang, 23\u0026ndash;58 years), an average time from injury to surgery of 4 days (rang, 1\u0026ndash;7 days), an average operation time of 117.5 minutes, and an average intraoperative blood loss of 71.7ml. All patients were hospitalized for 5 days, and all patients were able to walk with the assistance of a lumbar brace on the third day after surgery. All patients wore a thoracolumbar brace for 3 months after surgery. The mean follow-up time was 13.3 months (rang, 12\u0026ndash;14 months). All patients showed significant improvement in postoperative pain symptoms, with VAS scores of 6.3 points, 3 points, 0.2 points and 0.2 points before surgery, 3 days after surgery, 6 months after surgery and 12 months after surgery, respectively. The daily living ability was significantly improved. The mean value of ODI dysfunction index was 93.8% before surgery, 76.5% 3 days after surgery, 21.3% 6 months after surgery, and 6.2% 12 months after surgery. The ODI value decreased significantly after surgery. The clinical outcomes are summarized in Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eThe parameters of patients before and after operation\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"8\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eCase 1\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eCase 2\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eCase 3\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eCase 4\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003eCase 5\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003eCase 6\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c8\"\u003e \u003cp\u003eMean\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eOperation time (min)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e110\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e120\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e110\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e100\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e135\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e130\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e117.5\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eBlood loss (ml)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e50\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e50\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e80\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e100\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e50\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e100\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e71.7\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eHospital stay (days)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e5.0\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"8\" nameend=\"c8\" namest=\"c1\"\u003e \u003cp\u003e\u003cb\u003eVAS\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePre-operation\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e6.3\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e3 day post-op.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e3.0\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e6 months post-op.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e0.2\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e12 months post-op.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e0.2\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"8\" nameend=\"c8\" namest=\"c1\"\u003e \u003cp\u003e\u003cb\u003eODI (%)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePre-operation\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e98\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e94\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e93\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e91\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e91\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e96\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e93.8\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e3 day post-op.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e70\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e68\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e76\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e78\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e87\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e80\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e76.5\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e6 months post-op.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e22\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e18\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e16\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e20\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e25\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e27\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e21.3\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e12 months post-op.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e6.2\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"8\" nameend=\"c8\" namest=\"c1\"\u003e \u003cp\u003e\u003cb\u003eKyphosis (T11 - L2)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePre-operation\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e18\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e12\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e11\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e13\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e9\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e16\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e13.2\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e3 day post-op.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e3\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e2\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e1.5\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e6 months post-op.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e2\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e1.0\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e12 months post-op.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e4\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e4\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e1.5\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"8\" nameend=\"c8\" namest=\"c1\"\u003e \u003cp\u003e\u003cb\u003eLL\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePre-operation\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e21\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e31\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e29\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e39\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e41\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e39\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e33.3\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e3 days post-op.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e43\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e51\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e39\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e43\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e40\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e49\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e44.2\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e6 months post-op.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e45\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e56\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e28\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e45\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e48\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e52\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e45.7\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e12 months post-op.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e46\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e54\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e37\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e44\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e49\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e48\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e46.3\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"8\"\u003eODI, Oswestry Disability Index.\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eThe postoperation X-ray showed significant reduction of all injured vertebrae (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e). The average VBH of 14 injured vertebrae before surgery was 79.0%, and the VBH at 3 days, 6 months and 12 months after surgery was 95.6%, 93.3% and 93.1%, respectively (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e). Among them, the VBH of three injured vertebrae reached more than 97% after reduction, and the VBH of the one injured vertebrae with the worst reduction recovered to 85.0%. Compared with 3 days after surgery, the reduction height of injured vertebrae lost 2.5% on average at 12 months after surgery. Six patients had varied degrees of T11-L2 kyphosis before surgery. Kyphosis angle averaged 13.2\u0026deg; (rang, 9\u0026deg; -18 \u0026deg;), which decreased to 1.5\u0026deg; three days after surgery, 1.0\u0026deg; six months after surgery, and 1.5\u0026deg; twelve months after surgery. The reconstruction of lumbar lordosis angle was satisfied in 6 patients, the mean value of LL before surgery was 33.3\u0026deg;, which increased to 44.2\u0026deg; three days after surgery, 45.7\u0026deg; six months after surgery, and 46.3\u0026deg; twelve months after surgery. All the patients were re-examined during 12\u0026ndash;14 months after surgery, and the fracture recovered well without fracture or loosening of internal fixation, and the internal fixation were removed in the 6 patients. The clinical outcomes are summarized in Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e.\u003c/p\u003e"},{"header":"DISCUSSION","content":"\u003cp\u003eMultilevel thoracolumbar fractures are usually caused by high-energy injuries, and the number of fractured vertebrae is \u0026ge;\u0026thinsp;2, which presents new challenges for traditional surgical methods and internal fixation instruments. Traditional open surgery, with the long surgical incision and heavy damage, usually cause intractable back pain because that the paraspinal muscles are stripped twice in the process of implantation and removal of internal fixation.\u003csup\u003e14\u003c/sup\u003e Percutaneous minimally invasive internal fixation has the advantages of smaller trauma and faster healing. \u003csup\u003e11, 15\u003c/sup\u003e In 1982, Margrel reported the treatment of spinal fractures with percutaneous fixed-axis pedicle screws, providing a minimally invasive and effective treatment for biological healing of spinal fractures.\u003csup\u003e16\u003c/sup\u003e\u003c/p\u003e \u003cp\u003eHowever, existing methods for the treatment of multiple thoracolumbar fractures face substantial difficulties, due to the difficulty of setting the rod with fixed-axial screw and the reduction height loss with the multi-axial screw.\u003csup\u003e11, 17\u003c/sup\u003e The monoplanar pedicle screw is based on the fixed-axial screw, and the screw tail is limited to swing only in the axial plane, so it has the following advantages: 1.The screw tail can swing in the axial plane, which overcomes the disadvantage of the titanium rod implantation difficulty of the fixed-axis screw. 2. The tail of the screw has no moving angle in the sagittal plane, which overcomes the disadvantage of the poor reduction effect of multi-axis screw in sagittal position. The height loss rate of vertebral body was lower than that of multi-axial screw. 3. The arc of rod can be used to recover the height of the injured vertebra by locking the screw cap because of no swing angle in the sagittal plane.\u003c/p\u003e \u003cp\u003eFor patients with multiple thoracolumbar fractures, the main objectives of surgery are to recover the injured vertebra height as far as possible, restore normal lumbar lordosis and correct thoracolumbar kyphosis. We used this set of tools for the reduction of injured vertebrae in three main steps: 1.The patient was placed in the prone position after general anesthesia, and the abdomen was suspended and pressed moderately to achieve preliminary reduction. Especially for the patients with osteoporosis, the reduction of the position can avoid the surgical risks such as the loosening of the nail path caused by the severe prying force of the surgical instrument. 2. Using a rotary press to force the titanium rod with prebent radian into the tail slot. Schwab et al. reported that the LL\u0026thinsp;=\u0026thinsp;PI\u0026thinsp;\u0026plusmn;\u0026thinsp;9\u0026deg;, \u003csup\u003e18, 19\u003c/sup\u003e and upper lumbar lordosis accounts for approximately 33% of the entire lumbar lordosis.\u003csup\u003e20, 21\u003c/sup\u003e Therefore, careful preoperative measurement of PI is required for different patients, and the curvature of the titanium rod is also depending on this parameter. In order to obtain better reduction effect and lumbar lordosis angle, the curvature of the rod can be increased by 0\u0026ndash;10\u0026deg; on the basis of the calculated ideal angle.\u003csup\u003e17, 22\u003c/sup\u003e For patients with osteoporosis, there is no need to increase the curvature of the bending rod because of the pursuit of anatomical reduction of the vertebral body, so as not to cause loosening of the screw path. 3. If the height recovery of the injured vertebrae is still not satisfactory after the above two reduction procedures are completed, the final reduction of the injured vertebrae can be carried out using the distraction forceps. However, it is still recommended that the first two steps should be used for the reduction of injured vertebrae, and the force of prying should not be too large for the reduction of the third step, especially for patients with osteoporosis.\u003c/p\u003e \u003cp\u003eIn this report, all patients were successfully completed percutaneous titanium rod implantation with 3 groups of screws spanning 5 vertebral bodies. However, in our experience, rod placement is very difficult if the length exceeds 5 vertebras. In addition, there was no fracture of internal fixation in 6 patients during the whole follow-up period. We speculated that the use of screws with a diameter of 6.5 mm and rod with a diameter of 6.0 mm could meet the stress intensity requirements of this type of operation. More detailed biomechanical and stress analyses will be conducted in the future to further clarify the safety of this procedure. In conclusion, compared with open surgery, percutaneous screw fixation across the injured vertebrae has fewer traumas. The patients can moved to the ground 3 days after the operation, and has good reduction effect of the injured vertebrae, which can significantly reduce the occurrence of thoracolumbar kyphosis and prevent back pain in the later stage. This also makes patients with TLICS score of 4\u0026ndash;5 be confident to choose surgical treatment, avoid long-term bed immobility, long-term separation from society and work. Therefore, monoplanar pedicle screws have a good prospect in the treatment of multiple thoracolumbar fractures.\u003c/p\u003e"},{"header":"CONCLUSION","content":"\u003cp\u003eThe use of percutaneous monoplanar pedicle screws is a minimally invasive technique, and overcome the disadvantages, loss of the correction height of the injured vertebra and difficulty of implanting the rod. It can be very useful for the treatment of multiple thoracolumbar fractures.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e \u003ch2\u003eCONFLICT OF INTEREST\u003c/h2\u003e \u003cp\u003eThe authors have nothing to disclose.\u003c/p\u003e \u003c/p\u003e\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eXianglong Li and Yongfeng Zhang were responsible for this study design, surgical operation and manuscript writing. Hao Liu, Shuang Xu, Lidong Li and Beiyu Chen performed the data collecting, statistical analysis, patient follow-up. Zhe Wang and Tan Ding review the study proposal and fund this research. All authors read and approved the final manuscript.\u003c/p\u003e\u003ch2\u003eAcknowledgement\u003c/h2\u003e\u003cp\u003eNo\u003c/p\u003e\u003ch2\u003eData Availability\u003c/h2\u003e\u003cp\u003eThe datasets used and/or analysed in this study are available from the corresponding authors upon reasonable request\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eWang HW, Xiang Q, Li CQ, et al. Multiple-level noncontiguous spinal fractures: difference between the young and the elderly. J Spinal Disord Tech 2013;26: E272-E276.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKorres DS, Boscainos PJ, Papagelopoulos PJ, et al. Multiple level noncontiguous fractures of the spine. Clin Orthop Relat Res 2003;411:95\u0026ndash;102.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eTakami M, Okada M, Enyo Y, et al. Noncontiguous double-level unstable spinal injuries. Eur J Orthop Surg Traumatol 2017;27:79\u0026ndash;86.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eJaffray DC, Eisenstein SM, Balain B, et al. Early mobilisation of thoracolumbar burst fractures without neurology: a natural history observation. Bone Joint J 2016;98-B: 97\u0026ndash;101.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eWittenberg RH, Hargus S, Steffen R, et al. Noncontiguous unstable spine fractures. Spine (Phila Pa 1976) 2002;27: 254\u0026ndash;7.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSharif S, Shaikh Y, Yaman O, et al. Surgical Techniques for Thoracolumbar Spine Fractures: WFNS Spine Committee Recommendations. Neurospine 2021; 18: 667\u0026ndash;80.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eYe B, Yan M, Zhu HY, et al. Novel Screw Head Design of Pedicle Screw for Reducing the Correction Loss in the Patients With Thoracolumbar Vertebral Fractures. Spine (Phila Pa 1976) 2017;42:E379-E384.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eZhang SL, Yan M, Ding ZY, et al. Effect of indirect decompression with minimally invasive percutaneous uniplanar pedicle screw on canal encroachment rate and vertebral height in thoracolmbar fracture. Orthopaedics 2020; 11: 513\u0026ndash;7.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eFairbank JC, Pynsent PB. The Oswestry Disability Index. Spine (Phila Pa 1976) 2000;25:2940\u0026ndash;52.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eJanik TJ, Harrison DD, Cailliet R, et al. Can the Sagittal Lumbar Curvature be Closely Approximated by an Ellipse? J Orthop Res 1998;16:766\u0026ndash;70.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eWang HW, Zhou Y, Li CQ, et al. Comparison of Open Versus Percutaneous Pedicle Screw Fixation Using the Sextant System in the Treatment of Traumatic Thoracolumbar Fractures. Clin Spine Surg 2017;30: E239-E246.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMumford J, Weinstein JN, Spratt KF, et al. Thoracolumbar burst fractures. The clinical efficacy and outcome of nonoperative management. Spine (Phila Pa 1976) 1993;18:955\u0026ndash;70.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eDahdaleh NS, Smith ZA, Hitchon PW. Percutaneous Pedicle Screw Fixation for Thoracolumbar Fractures. Neurosurg Clin N Am 2014;25: 337\u0026thinsp;\u0026ndash;\u0026thinsp;46.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003e\u0026Ouml;kten Aİ, Gezercan Y, \u0026Ouml;zsoy KM, et al. Results of treatment of unstable thoracolumbar burst fractures using pedicle instrumentation with and without fracture-level screws. Acta Neurochir (Wien) 2015;157:831\u0026ndash;6.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003ePannu CD, Farooque K, Sharma V, et al. 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Radiol Bras 2020;53:175\u0026ndash;84.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eGuo JM, A.Li MJ. Relationship between Low Back Pain and Lumbar Lordosis and Sacral Inclination in Adult People. Journal of practical orthopaedics 2007;13: 577\u0026ndash;9.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eNakipoğlu GF, Karag\u0026ouml;z A, Ozgirgin N. The Biomechanics of the Lumbosacral Region In Acute And Chronic Low Back Pain Patients. Pain Physician 2008; 11: 505\u0026ndash;11.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eYang M, Zhao QP, Hao DJ, et al. Comparison of clinical results between novel percutaneous pedicle screw and traditional open pedicle screw fixation for thoracolumbar fractures without neurological deficit. Int Orthop 2019;43:1749\u0026ndash;54.\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"multilevel thoracolumbar fractures, percutaneous internal fixation, minimally invasive, monoplanar pedicle screw","lastPublishedDoi":"10.21203/rs.3.rs-4696595/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-4696595/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eFixed-axis screw and polyaxial screw exposed many disadvantages in the treatment of multiple thoracolumbar fractures. This is the first report on the treatment of multiple thoracolumbar fractures with percutaneous axial monoplanar pedicle screw. Six patients with multiple vertebral fractures were treated with monoplanar pedicle screw implantation and distraction reduction under general anesthesia. The height correction of injured vertebrae, T11-L2 kyphosis angle, Visual Analogue Scale (VAS) and Oswestry Disability Index (ODI) scores were measured before and after operation to evaluate the effectiveness of surgical treatment. All patients underwent smooth surgery, with an average operation time of 117.5 minutes and an average intraoperative blood loss of 71.7 ml. All patients were able to walk with the aid of a waist brace on the 3rd postoperative day and discharged on the 4th postoperative day. Low back pain symptoms were significantly relieved after operation. VAS score, ODI dysfunction index, the height correction of injured vertebrae, T11-L2 kyphosis angle and LL were all satisfactorily corrected immediately after surgery, and satisfactory results were maintained at 6 and 12 months after surgery. All patients received minimally invasive removal of internal fixation at the original surgical incision during 12\u0026ndash;14 months after surgery, and the injured vertebrae were well reduced without significant height loss of the injured vertebrae. The use of percutaneous monoplanar pedicle screws for the treatment of multiple thoracolumbar fractures is a minimally invasive technique with satisfactory long-term reduction effect.\u003c/p\u003e","manuscriptTitle":"Percutaneous internal fixation with the monoplanar pedicle screws in the treatment of multilevel thoracolumbar fractures: a case series of 6 cases","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-09-12 12:36:39","doi":"10.21203/rs.3.rs-4696595/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"7516a42e-628f-41cb-91a9-4fc2e88f4f5a","owner":[],"postedDate":"September 12th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[{"id":36550778,"name":"Health sciences/Diseases/Trauma"},{"id":36550779,"name":"Health sciences/Health care/Fracture repair"}],"tags":[],"updatedAt":"2025-09-07T17:38:25+00:00","versionOfRecord":[],"versionCreatedAt":"2024-09-12 12:36:39","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-4696595","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-4696595","identity":"rs-4696595","version":["v1"]},"buildId":"zQwnuV7TCBrMSSSToR1PI","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}