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Henao Romero S, Sierra Peña JA, Diaz Orduz RC, Berbeo-Calderon ME. Horizontal Gaze Assessment: An Extensive Narrative Review. World Neurosurg 2024; 187:e1011-e1016. [PMID: 38750886 DOI: 10.1016/j.wneu.2024.05.035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2024] [Accepted: 05/07/2024] [Indexed: 06/09/2024]
Abstract
OBJECTIVE Bipedalism was a significant milestone in the evolutionary development of Homo sapiens sapiens, influencing neocortical evolution and subsequent behavioral changes. Coordinated visual and sensory inputs are crucial for posture, environmental interaction, and surgical planning, with horizontal gaze being a pivotal parameter. This narrative review aims to explore various geometric measures used to assess horizontal gaze in patients, highlighting their applications in surgical planning. METHODS A literature review was conducted in indexed databases using Mesh terms like "Cervical Vertebrae" and "Visual Fields" along with keywords such as "horizontal gaze" and "sagittal spine parameters." Among 477 initially identified articles, 41 were selected for inclusion after rigorous filtering. RESULTS The most recognized method for assessing horizontal gaze is the Chin Brow Vertical Angle (CBVA), initially described in patients with ankylosing spondylitis. Clinical photography is employed as a tool for CBVA calculation, while other measures like McGregor slope and Slope of the Line of Sight have been considered as alternatives to CBVA. Each method presents its unique advantages and limitations. CONCLUSIONS This review highlights the need for further research into horizontal gaze measurement methods. Developing novel approaches to determine horizontal gaze can significantly enhance surgical planning and, consequently, improve patient outcomes. The ongoing exploration of these geometric measures offers promising prospects for advancing the field and optimizing patient care.
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Affiliation(s)
- Sara Henao Romero
- Department of Neurosurgery, Hospital Universitario San Ignacio, Pontificia Universidad Javeriana, Bogotá, Colombia; Neurosurgery research seedbed, Pontificia Universidad Javeriana, Bogotá, Colombia.
| | | | - Roberto Carlos Diaz Orduz
- Department of Neurosurgery, Hospital Universitario San Ignacio, Pontificia Universidad Javeriana, Bogotá, Colombia
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Kim DH, Hong JT, Hur JW, Kim IS, Lee HJ, Lee JB. Clinical and Radiological Outcomes in C2 Recapping Laminoplasty for the Pathologies in the Upper Cervical Spine. Neurospine 2024; 21:565-574. [PMID: 38955529 PMCID: PMC11224761 DOI: 10.14245/ns.2347270.635] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2023] [Revised: 01/31/2024] [Accepted: 02/09/2024] [Indexed: 07/04/2024] Open
Abstract
OBJECTIVE To evaluate C2 muscle preservation effect and the radiological and clinical outcomes after C2 recapping laminoplasty. METHODS Fourteen consecutive patients who underwent C2 recapping laminoplasty around C1-2 level were enrolled. To evaluate muscle preservation effect, the authors conducted a morphological measurement of extensor muscles between the operated and nonoperated side. Two surgeons measured the cross-sectional area (CSA) of obliquus capitis inferior (OCI) and semispinalis cervicis (SSC) muscle before and after surgery to determine atrophy rates (ARs). Additionally, we examined range of motion (ROM), sagittal vertical axis (SVA), neck visual analogue scale (VAS), Neck Disability Index (NDI), and Japanese Orthopaedic Association (JOA) score to assess potential changes in alignment and consequent clinical outcomes following posterior cervical surgery. RESULTS We measured the CSA of OCI and SSC before surgery, and at 6 and 12 months postoperatively. Based on these measurements, the AR of the nonoperated SSC was 0.1% ± 8.5%, the AR of the operated OCI was 2.0% ± 7.2%, and the AR of the nonoperated OCI was -0.7% ± 5.1% at the 12 months after surgery. However, the AR of the operated side's SSC was 11.2% ± 12.5%, which is a relatively higher value than other measurements. Despite the atrophic change of SSC on the operated side, there were no prominent changes observed in SVA, C0-2 ROM, and C2-7 ROM between preoperative and 12 months postoperative measurements, which were 11.8 ± 10.9 mm, 16.3° ± 5.9°, and 48.7° ± 7.7° preoperatively, and 14.1 ± 11.6 mm, 16.1° ± 7.2°, and 44.0° ± 10.3° at 12 months postoperative, respectively. Improvement was also noted in VAS, NDI, and JOA scores after surgery with JOA recovery rate of 77.3% ± 29.6%. CONCLUSION C2 recapping laminoplasty could be a useful tool for addressing pathologies around the upper cervical spine, potentially mitigating muscle atrophy and reducing postoperative neck pain, while maintaining sagittal alignment and ROM.
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Affiliation(s)
- Dong Hun Kim
- Department of Neurosurgery, Eunpyeong St. Mary’s Hospital, The Catholic University of Korea, Seoul, Korea
| | - Jae Taek Hong
- Department of Neurosurgery, Eunpyeong St. Mary’s Hospital, The Catholic University of Korea, Seoul, Korea
| | - Jung Woo Hur
- Department of Neurosurgery, Eunpyeong St. Mary’s Hospital, The Catholic University of Korea, Seoul, Korea
| | - Il Sup Kim
- Department of Neurosurgery, St. Vincent Hospital, The Catholic University of Korea, Suwon, Korea
| | - Ho Jin Lee
- Department of Neurosurgery, St. Vincent Hospital, The Catholic University of Korea, Suwon, Korea
| | - Jong Beom Lee
- Department of Neurosurgery, Chungbuk National University Hospital, Cheongju, Korea
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Olivares-Camacho JL, Olivares Peña JL, Cuevas-Hernández AA, Hernández-Alcázar EDJ, Jiménez-Ponce F. Analyzing results of cervical sagittal parameters in patients operated with polyetheretherketone cages without plate. JOURNAL OF CRANIOVERTEBRAL JUNCTION AND SPINE 2024; 15:230-235. [PMID: 38957757 PMCID: PMC11216644 DOI: 10.4103/jcvjs.jcvjs_35_24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2024] [Accepted: 03/27/2024] [Indexed: 07/04/2024] Open
Abstract
Study Design This was a retrospective longitudinal observational study. Purpose The purpose of this study was to analyze the results of cervical sagittal parameters on preoperative and postoperative lateral radiographs in anterior cervical discectomy and fusion (ACDF). ACDF is believed to change craniocervical parameters and thus cervical curvature using polyetheretherketone (PEEK) or titanium cages with or without self-locking as well as an anterior plate, the latter of which has not been shown to provide better clinical or radiological results. Overview of Literature Cervical spondylotic myelopathy (CSM) is a common degenerative pathology that can affect one or more levels and treatment has varied over time trying to maintain sagittal parameters within acceptable values where the ACDF is the main treatment. Materials and Methods The study was performed in patients with CSM who underwent anterior cervical discectomy, and their pre- and postoperative radiographs were analyzed using Surgimap software a few days before and 3 months after surgery. Results Fifteen files were included in the study. Statistically significant sagittal balance variables were observed in cervical lordosis (CL) with an increase of 4.73° (P = 0.019) and T1 slope (T1S)-CL with a decrease of -5.93° (P = 0.007). Conclusions CL and T1S-CL showed favorably modified values when performing ACDF using stand-alone PEEK cages without the need for self-blocking or an anterior plate.
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Affiliation(s)
| | - Jorge Luis Olivares Peña
- Department of Orthopaedic Surgery, Hospital Angeles Pedregal, Mexico City, Mexico
- Specialty Hospital ’’Dr. Antonio Fraga Mouret’’ of National Medical Center ’’La Raza’’, Mexico City, Mexico
| | - Aldo Adrián Cuevas-Hernández
- Higher School of Medicine of National Polytechnic Institute, Mexico City, Mexico
- Research Division, Hospital Angeles Pedregal, Mexico City, Mexico
| | - Edgar De Jesús Hernández-Alcázar
- Higher School of Medicine of National Polytechnic Institute, Mexico City, Mexico
- Research Division, Hospital Angeles Pedregal, Mexico City, Mexico
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Wang S, Shi J, Sun J. How cervical curvature changes after ACAF and ACDF: a radiological retrospective study. Neurosurg Rev 2023; 46:188. [PMID: 37523095 DOI: 10.1007/s10143-023-02049-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2023] [Revised: 06/02/2023] [Accepted: 06/10/2023] [Indexed: 08/01/2023]
Abstract
To assess changes in cervical curvature and demonstrate the feasibility of using ACAF technology to restore lordosis, imaging data from patients undergoing multilevel ACAF and ACDF surgeries were retrospectively analyzed. Forty-seven patients receiving multilevel ACAF and ACDF were included in the study. Total cervical curvature and anterior, middle, and posterior column curvature, spinal canal diameter, cervical range of motion, and surgical complications were measured and analyzed by non-parametric or chi-square tests before and after surgery. The Spearman correlation between imaging data was analyzed. Compared with ACDF, the operation time of the ACAF group was longer, the cervical motion was larger, the median and change value of the middle column curvature was larger, and the change value of the posterior column curvature was smaller (P < 0.05). The postoperative differences in cervical lordosis angle, vertebral canal diameter, and middle and posterior column curvature in the ACAF group were significantly greater than those in the ACDF group (p = 0.015). The expansion of vertebral canal diameter was significantly correlated with the difference in curvature between the middle and posterior columns (r = 0.523, P < 0.01), and the curvature of the anterior column was correlated with that of the middle and posterior columns (P < 0.05). The curvature change of the anterior column is closely related to the curvature change of the middle column and the posterior column. Compared with ACDF, ACAF expands the diameter and volume of the spinal canal by increasing the curvature of the middle column and reducing the anterior movement of the posterior column.
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Affiliation(s)
- Shunmin Wang
- Department of Orthopedic Surgery, Spine Center, Changzheng Hospital, Second Military Medical University No.415 Fengyang Road, Shanghai, 200003, People's Republic of China
- 910 Hospital of China Joint Logistics Support Force, 180 Garden Road, Fengze District, Quanzhou City, Fujian Province, People's Republic of China
| | - Jiangang Shi
- Department of Orthopedic Surgery, Spine Center, Changzheng Hospital, Second Military Medical University No.415 Fengyang Road, Shanghai, 200003, People's Republic of China.
| | - Jingchuan Sun
- Department of Orthopedic Surgery, Spine Center, Changzheng Hospital, Second Military Medical University No.415 Fengyang Road, Shanghai, 200003, People's Republic of China.
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Park MS, Moon SH, Kim YW, Lim JK, Jung JH, Kim TS, Reidler JS, Riew KD. The Effect of Cervical Fusion on Functional Sagittal Spinal Alignment Based on the Inflection Point: Case Series Study. Global Spine J 2023; 13:643-650. [PMID: 33719639 DOI: 10.1177/21925682211001795] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
Abstract
STUDY DESIGN A retrospective radiologic study. OBJECTIVE The inflection point is the disc space between a lordotic and kyphotic segment of spine. To our knowledge, there has been no study evaluating changes in functional sagittal alignment determined by inflection points after cervical fusion surgery. The purpose is to identify changes in functional sagittal alignment after cervical fusion as determined by functional segments between cervicothoracic and thoracolumbar inflection points. METHODS Standing radiographs of the sagittal whole spine were taken in 62 patients who underwent cervical fusion procedures. We identified cervicothoracic and thoracolumbar inflection points in the sagittal plane and measured Cobb angles of resulting "functional" cervical, thoracic, and lumbar segments. We also measured the C2 and T1 sagittal vertical axis (SVA) distance to S1 and the anatomic cervical lordosis, thoracic kyphosis, lumbar lordosis, spinopelvic parameters, and T1 sagittal slope. We compared the pre- and post-op values. RESULTS The functional cervical segment and T1 sagittal slope increased postoperatively. C2 and T1 SVA distance to S1 decreased postoperatively. In patients with a single level fusion or lower instrumented vertebra (LIV) proximal or equal to C6, functional cervical segment, and anatomic cervical lordosis increased postoperatively. In those with multiple level fusion or LIV distal or equal to C7, the C2 SVA distance to S1 decreased postoperatively. CONCLUSIONS After cervical fusion surgery, functional cervical sagittal parameters determined by the inflection point improve without changes in the anatomic sagittal parameters. Postoperative changes in functional sagittal parameters were affected by the number of fused levels and LIV.
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Affiliation(s)
- Moon Soo Park
- Department of Orthopaedic Surgery, Hallym University Dongtan Sacred Heart Hospital, Medical College of Hallym University, Gyeonggi-do, Republic of Korea
| | - Seong-Hwan Moon
- Department of Orthopaedic Surgery, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Young-Woo Kim
- Department of Orthopaedic Surgery, Hallym University Dongtan Sacred Heart Hospital, Medical College of Hallym University, Gyeonggi-do, Republic of Korea
| | - Jin Kyu Lim
- Department of Orthopaedic Surgery, Kangdong Sacred Heart Hospital, Hallym University College of Medicine, Seoul, Republic of Korea
| | - Jong Ho Jung
- Department of Orthopaedic Surgery, Hallym University Sacred Heart Hospital, Medical College of Hallym University, Gyeonggi-do, Republic of Korea
| | - Tae Soung Kim
- Department of Orthopaedic Surgery, Hallym University Dongtan Sacred Heart Hospital, Medical College of Hallym University, Gyeonggi-do, Republic of Korea
| | - Jay S Reidler
- Department of Orthopedic Surgery, Columbia University, NewYork-Presbyterian Och Spine Hospital, New York, NY, USA
| | - K Daniel Riew
- Department of Orthopedic Surgery, Columbia University, NewYork-Presbyterian Och Spine Hospital, New York, NY, USA
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Wang W, Xue C, Ma X, Feng H, Ma Z, Guan X, Chen X, Zhang X. Extension of decompression to C2 doesn't affect the spinal sagittal parameters compared with standard open-door laminoplasty. Medicine (Baltimore) 2022; 101:e32532. [PMID: 36595870 PMCID: PMC9794331 DOI: 10.1097/md.0000000000032532] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
We modified and extended laminoplasty to the upper cervical spine on patients with canal stenosis associated with upper cervical spinal ossified lesions. However, whether the extended decompression range of laminoplasty can cause further effects on cervical stability is rarely studied at present. A retrospective study to analyze the relationship between the surgical levels and cervical sagittal parameters effects was performed in patients with cervical spondylosis myelopathy who had undergone posterior cervical expansive open-door laminoplasty with/without extending to C2. In total, 64 patients were divided into 2 groups according to the surgical levels. Radiologic outcomes of occipito-cervical angle (C0-2 Cobb angle), CL C27 Cobb angle, cervical sagittal vertical alignment, T1-Slope (T1S), T1S minus CL (T1S-CL), spino-cranial angle and center of the sella turcica-C7 SVA (St-SVA) were evaluated on lateral X-rays of the cervical spine at pre-operation, post-operation, and 2-year follow-up. The patient's health-related quality of life was obtained including neck disability index, Japanese orthopaedic association scores, and visual analog scale. Changes in sagittal parameters were observed in both groups after surgery. T1S, cervical sagittal vertical alignment, and T1S-CL significantly increased and CL decreased in 2 groups of patients postoperative. After a 2-year follow-up period, the C0-2 Cobb angle was found to increase compared to preoperative records. In addition, there were no significant differences in spino-cranial angle and st-SVA between preoperative and 2 years follow-up measurements. Health-related quality of life was improved in both groups and was not significantly different. Herein, the parameters indicated a tilting forward of the lower cervical spine and a more lordotic upper cervical spine to maintain a horizontal gaze in patients. However, C2 to 7 laminoplasty was performed to achieve satisfactory clinical results without significantly changing the spinal sagittal parameters.
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Affiliation(s)
- Wenxuan Wang
- Third Hospital of Shanxi Medical University, Shanxi Bethune Hospital, Shanxi Academy of Medical Sciences, Tongji Shanxi Hospital, Taiyuan, China
| | - Chenhui Xue
- Third Hospital of Shanxi Medical University, Shanxi Bethune Hospital, Shanxi Academy of Medical Sciences, Tongji Shanxi Hospital, Taiyuan, China
| | - Xun Ma
- Third Hospital of Shanxi Medical University, Shanxi Bethune Hospital, Shanxi Academy of Medical Sciences, Tongji Shanxi Hospital, Taiyuan, China
- Department of Orthopedics, Shanxi Bethune Hospital, Shanxi Academy of Medical Sciences, Tongji Shanxi Hospital, Third Hospital of Shanxi Medical University, Taiyuan, China
- * Correspondence: Xun Ma, Third Hospital of Shanxi Medical University, Shanxi Bethune Hospital, Shanxi Academy of Medical Sciences, Tongji Shanxi Hospital, Taiyuan 030032, China (e-mail: )
| | - Haoyu Feng
- Department of Orthopedics, Shanxi Bethune Hospital, Shanxi Academy of Medical Sciences, Tongji Shanxi Hospital, Third Hospital of Shanxi Medical University, Taiyuan, China
| | - Zhuo Ma
- Department of Orthopedics, Shanxi Bethune Hospital, Shanxi Academy of Medical Sciences, Tongji Shanxi Hospital, Third Hospital of Shanxi Medical University, Taiyuan, China
| | - Xiaoming Guan
- Department of Orthopedics, Shanxi Bethune Hospital, Shanxi Academy of Medical Sciences, Tongji Shanxi Hospital, Third Hospital of Shanxi Medical University, Taiyuan, China
| | - Xu Chen
- Department of Orthopedics, Shanxi Bethune Hospital, Shanxi Academy of Medical Sciences, Tongji Shanxi Hospital, Third Hospital of Shanxi Medical University, Taiyuan, China
| | - Xin Zhang
- Third Hospital of Shanxi Medical University, Shanxi Bethune Hospital, Shanxi Academy of Medical Sciences, Tongji Shanxi Hospital, Taiyuan, China
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Lee JK, Hyun SJ, Yang SH, Kim KJ. Reciprocal Changes Following Cervical Realignment Surgery. Neurospine 2022; 19:853-861. [PMID: 36597620 PMCID: PMC9816596 DOI: 10.14245/ns.2249938.469] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Accepted: 11/28/2022] [Indexed: 12/27/2022] Open
Abstract
Over the last few decades, the importance of the sagittal plane and its contour has gained significant recognition. Through full-body stereoradiography, the understanding of compensatory mechanisms, and the concept of global balance and reciprocal change has expanded. There have been a few reports describing how cervical realignment surgery affects global spinal alignment (GSA) and global balance. Despite the research efforts, the concept of reciprocal change and global balance is still perplexing. Understanding the compensatory status and main drivers of deformity in a patient is vital because the compensatory mechanisms may resolve reciprocally following cervical realignment surgery. A meticulous preoperative evaluation of the whole-body alignment, including the pelvis and lower extremities, is paramount to appreciate optimal GSA in the correction of spinal malalignment. This study aims to summarize relevant literature on the reciprocal changes in the whole body caused by cervical realignment surgery and review recent perspectives regarding cervical compensatory mechanisms.
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Affiliation(s)
- Jae-Koo Lee
- Department of Neurosurgery, Spine Center, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam, Korea
| | - Seung-Jae Hyun
- Department of Neurosurgery, Spine Center, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam, Korea
| | - Seung Heon Yang
- Department of Neurosurgery, Spine Center, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam, Korea
| | - Ki-Jeong Kim
- Department of Neurosurgery, Spine Center, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam, Korea
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[Normative values of cervical sagittal alignment according to the whole spine balance: Based on 126 asymptomatic Chinese young adults]. BEIJING DA XUE XUE BAO. YI XUE BAN = JOURNAL OF PEKING UNIVERSITY. HEALTH SCIENCES 2022; 54. [PMID: 35950397 PMCID: PMC9385534 DOI: 10.19723/j.issn.1671-167x.2022.04.021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
OBJECTIVE To explore the normal distribution of cervical sagittal alignment and the relationship between cervical alignment and global spine balance in asymptomatic young adults. METHODS A cohort of 272 asymptomatic Chinese adults (including 161 males and 111 females, with an average age of (23.2±4.4) years, ranging from 18 to 45 years) were prospectively recruited from November 2011 to December 2014. The C0-C2 angle, disk angles from C2-C3 to C6-C7, vertebral angles from C3 to C7, T1 slope, thoracic kyphosis (TK), lumbar lordosis (LL), pelvic incidence (PI), sacral slope (SS), C2-C7 sagittal vertical axis (C2-C7SVA), center of gravity of head to C7SVA (CGH-C7SVA), C7-S1SVA were measured and statistically analyzed. All the subjects were categorized with the Roussouly classification and the cervical morphologies were evaluated as lordotic, straight, sigmoid or kyphotic. Spinal sagittal alignment parameters were compared between different sexes and Roussouly classifications with independent student t test, analysis of variance (ANOVA) or Chi-square test. Correlations between cervical sagittal alignment and global spine sagittal alignment were calculated using the Pearson and Spearman correlation coefficient. Linear regression analysis was performed. RESULTS Sixty-seven males and 59 females aged from 18 to 30 years old were included in the study. The mean value of C0-C7 was 26.0°±12.8°, composed of 15.2°±6.7° for C0-C2, 9.1°±12.1° for sum of disk angles from C2-C3 to C6-C7, and 1.4°±10.2° for sum of vertebral angles from C3 to C7. C2-C7SVA [(18.6±7.9) mm] and CGH-C7SVA [(22.9±12.3) mm]were offset ideally by C7-S1SVA [(-21.6±31.0) mm]. Males had a larger T1 slope (P < 0.05) and accordingly, a larger cervical lordosis C2-C7 (P < 0.01) and C0-C7 angle (P < 0.01) than females. Males had a smaller C7-S1SVA (P < 0.01) and accordingly, a smaller CGH-C7SVA (P=0.165) than females. Significant difference was found between cervical alignment of different Roussouly types (P < 0.01). In general, a larger LL was consistent with a set of larger TK, C2-C7angle, C0-C7 angle, and vice versa. There was no significant correlation between cervical morphology and the Roussouly classification (Chi-square=10.548, P=0.308). There was significant correlation between cervical alignment and T1 slope (P < 0.01), TK (P < 0.01). There was significant correlation between adjacent segmental angles from T1 slope up to C0-C2 angle (P < 0.05). CONCLUSION Normative values of each vertebral angle and disk angle were established. The cervical lordosis occurred mainly at C0-C2 and disk levels, which was influenced by parameters of other parts of the spine, such as T1 slope, TK and the Roussouly classification. There was significant correlation between adjacent disk angles.
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Divi SN, Karamian BA, Canseco JA, Chang M, Toci GR, Goyal DKC, Nicholson KJ, Mujica VE, Bronson W, Kaye ID, Kurd MF, Woods BI, Radcliff KE, Rihn JA, Anderson DG, Hilibrand AS, Kepler CK, Vaccaro AR, Schroeder GD. The Impact of Upper Cervical Spine Alignment on Patient-reported Outcome Measures in Anterior Cervical Decompression and Fusion. Clin Spine Surg 2022; 35:E539-E545. [PMID: 35302961 DOI: 10.1097/bsd.0000000000001310] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/22/2021] [Accepted: 02/02/2022] [Indexed: 11/26/2022]
Abstract
STUDY DESIGN This was a retrospective cohort study. OBJECTIVE To determine the extent to which the upper cervical spine compensates for malalignment in the subaxial cervical spine, and how changes in upper cervical spine sagittal alignment affect patient-reported outcomes. SUMMARY OF BACKGROUND DATA Previous research has investigated the relationship between clinical outcomes and radiographic parameters in the subaxial cervical spine following anterior cervical discectomy and fusion (ACDF). However, limited research exists regarding the upper cervical spine (occiput to C2), which accounts for up to 40% of neck movement and has been hypothesized to compensate for subaxial dysfunction. MATERIALS AND METHODS Patients undergoing ACDF for cervical radiculopathy and/or myelopathy at a single center with minimum 1-year follow-up were included. Radiographic parameters including cervical sagittal vertical axis, C0 angle, C1 inclination angle, C2 slope, Occiput-C1 angle (Oc-C1 degrees), Oc-C2 degrees, Oc-C7 degrees, C1-C2 degrees, C1-C7 degrees, and C2-C7 degrees cervical lordosis (CL) were recorded preoperatively and postoperatively. Delta (Δ) values were calculated by subtracting preoperative values from postoperative values. Correlation analysis as well as multiple linear regression analysis was used to determine relationships between radiographic and clinical outcomes. Alpha was set at 0.05. RESULTS A total of 264 patients were included (mean follow-up 20 mo). C2 slope significantly decreased for patients after surgery (Δ=-0.8, P =0.02), as did parameters of regional cervical lordosis (Oc-C7 degrees, C1-C7 degrees, and C2-C7 degrees; P <0.001, <0.001, and 0.01, respectively). Weak to moderate associations were observed between postoperative CL and C1 inclination ( r =-0.24, P <0.001), Oc-C1 degrees ( r =0.59, P <0.001), and C1-C2 degrees ( r =-0.23, P <0.001). Increased preoperative C1-C2 degrees and Oc-C2 degrees inversely correlated with preoperative SF-12 Mental Composite Score (MCS-12) scores ( r =-0.16, P =0.01 and r =-0.13, P =0.04). Cervical sagittal vertical axis was found to have weak but significant associations with Short Form-12 (SF-12) Physical Composite Score (PCS-12) ( r =-0.13, P =0.03) and MCS-12 ( r =0.12, P =0.05). CONCLUSION No clinically significant relationship between upper cervical and subaxial cervical alignment was detected for patients undergoing ACDF for neurological symptoms. Upper cervical spine alignment was not found to be a significant predictor of patient-reported outcomes after ACDF. LEVEL OF EVIDENCE Level III.
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Affiliation(s)
- Srikanth N Divi
- Department of Orthopaedic Surgery, Rothman Institute, Thomas Jefferson University, Philadelphia, PA
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Lee JK, Hyun SJ, Kim KJ. Odontoid Incidence: A Novel Cervical Parameter Influencing Cervical Alignment From Top to Bottom. Neurospine 2022; 19:463-471. [PMID: 35793937 PMCID: PMC9260555 DOI: 10.14245/ns.2244220.110] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Accepted: 06/07/2022] [Indexed: 11/29/2022] Open
Abstract
Objective By using angulation of the axis itself, this study aims to define and analyze odontoid incidence (OI) and odontoid tilt (OT) as novel cervical alignment parameters and investigate their correlations with cervical alignment.
Methods Novel and existing parameters were measured with whole-spine lateral plain radiographs and EOS images of 42 adults without cervical symptoms. The correlations of OI, OT, C2 slope (C2S), and T1 slope (T1S) were calculated.
Results The OI, OT, and C2S showed significant correlations with C2–7 angle (r = 0.43, r = -0.42, r = 0.62, respectively) and C0–2 angle (r = -0.33, r = 0.48, r = -0.61, respectively). OI, OT, T1S were independent predictors of the C2–7 angle in univariate regression analysis (adjusted-R2 = 0.17, R2 = 0.15, R2 = 0.28, respectively). OI, OT, and T1S were independent predictors in the multivariable regression analysis with estimated standardized coefficients of 0.36, -0.67, -0.69, respectively (adjusted- R2 = 0.80, p < 0.001). Regarding the C0–2 angle, OI and OT were independent predictors in the univariate regression analysis (adjusted-R2 = 0.08, R2 = 0.21, respectively).
Conclusion OI, OT, and C2S had significant correlations with cervical alignment. As the pelvic incidence, the OI is the only anatomical and constant parameter that could be used as a reference point related to the cervical spine from the rostral end. The study results may serve as baseline data for further studies on the alignment and balance of the cervical spine.
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Affiliation(s)
- Jae-Koo Lee
- Department of Neurosurgery, Spine Center, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam, Korea
| | - Seung-Jae Hyun
- Department of Neurosurgery, Spine Center, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam, Korea
- Corresponding Author Seung-Jae Hyun Department of Neurosurgery, Spine Center, Seoul National University Bundang Hospital, Seoul National University College of Medicine, 82 Gumi-ro 173beongil, Bundang-gu, Seongnam 13620, Korea
| | - Ki-Jeong Kim
- Department of Neurosurgery, Spine Center, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam, Korea
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Zhu C, Wang LN, Chen TY, Mao LL, Yang X, Feng GJ, Liu LM, Song YM. Sequential sagittal alignment changes in the cervical spine after occipitocervical fusion. World J Clin Cases 2022; 10:1172-1181. [PMID: 35211550 PMCID: PMC8855180 DOI: 10.12998/wjcc.v10.i4.1172] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/06/2021] [Revised: 11/13/2021] [Accepted: 12/31/2021] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND There are few studies regarding sequential changes in the sagittal alignment of the upper and lower cervical regions of the spine after occipitocervical fusion (OCF). In addition, no comparisons of cervical sagittal alignment (CSA) between patients with craniocervical junction disorders (CJDs) and normal populations have been reported.
AIM To compare the CSA of patients with CJDs with that of normal controls and investigate the sequential changes in the CSA of the upper and lower cervical spine after OCF.
METHODS Eighty-four patients who underwent OCF (OCF group) and 42 asymptomatic volunteers (control group) were included. Radiographic parameters, including the occipital to C2 angle (O-C2a), occipital and external acoustic meatus to axis angle (O-EAa), C2–7 angle (C2-7a), and pharyngeal inlet angle (PIA), were measured and compared pre- and postoperatively. The correlations among the parameters were analyzed using Pearson’s correlation test.
RESULTS The O-C2a and PIA of the OCF group were smaller than those of the control group, while their O-EAa and C2-7a values were larger than those of the normal controls. There were no significant differences in O-C2a, C2-7a, or PIA in the OCF group at baseline, 1 mo, or the final follow-up after surgery. The Pearson’s correlation results showed that there were significant correlations between the O-C2a and C2Ta, C2-7a, C2-7 sagittal vertical axis (SVA), and PIA at 1 mo after OCF surgery and between O-C2a and O-EAa, C2Ta, C2-7a, C2-7 SVA, and PIA at the final follow-up.
CONCLUSION Patients with CJDs have a more kyphotic upper CSA and a more lordotic lower CSA than normal controls. The effectiveness of OCF surgery in restoring CSA may be limited by the realignment of the craniocervical junction being neglected. The reduction in O-C2a after OCF surgery may increase C2-7a and decrease PIA.
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Affiliation(s)
- Ce Zhu
- Department of Orthopedics Surgery and Orthopedics Research Institute, West China Hospital of Sichuan University, Chengdu 610041, Sichuan Province, China
| | - Lin-Nan Wang
- Department of Orthopedics Surgery and Orthopedics Research Institute, West China Hospital of Sichuan University, Chengdu 610041, Sichuan Province, China
| | - Tai-Yong Chen
- Department of Orthopedics Surgery, The Second Affiliated Hospital of Zunyi Medical University, Zunyi 563000, Guizhou Province, China
| | - Li-Li Mao
- Department of Ultrasound, Hospital of Traditional Chinese Medicine Affiliated to Southwest Medical University, Luzhou 646000, Sichuan Province, China
| | - Xi Yang
- Department of Orthopedics Surgery and Orthopedics Research Institute, West China Hospital of Sichuan University, Chengdu 610041, Sichuan Province, China
| | - Gan-Jun Feng
- Department of Orthopedics Surgery and Orthopedics Research Institute, West China Hospital of Sichuan University, Chengdu 610041, Sichuan Province, China
| | - Li-Min Liu
- Department of Orthopedics Surgery and Orthopedics Research Institute, West China Hospital of Sichuan University, Chengdu 610041, Sichuan Province, China
| | - Yue-Ming Song
- Department of Orthopedics Surgery and Orthopedics Research Institute, West China Hospital of Sichuan University, Chengdu 610041, Sichuan Province, China
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Lee HJ, You ST, Sung JH, Kim IS, Hong JT. Analyzing the Significance of T1 Slope minus Cervical Lordosis in Patients with Anterior Cervical Discectomy and Fusion Surgery. J Korean Neurosurg Soc 2021; 64:913-921. [PMID: 34749484 PMCID: PMC8590907 DOI: 10.3340/jkns.2021.0011] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2021] [Accepted: 03/03/2021] [Indexed: 11/27/2022] Open
Abstract
Objective Accurate measurement of T1 slope (a component of T1s minus cervical lordosis [CL]) is often constrained by anatomical limitations. In this situation, efforts should be made to find the exact meaning of T1s-CL and whether there are any alternatives to it.
Methods We enrolled 117 patients who received two-level anterior cervical discectomy and fusion (ACDF). Occipital slope, C2 slope (C2s), C7 slope (C7s), T1, O-C2 angle (O-C2A), C2-7 angle (C2-7A), O-C7 angle (O-C7A), T1s-CL, C7-T1 angle (C7-T1A), and C2-7 sagittal vertical axis were measured. We determined 16° (T1s-CL) as the reference point for dividing subjects into the mismatch group and the balance group, and a comparative analysis was performed.
Results The mean value of C7-T1A was constantly maintained within 2.6° peri-operatively. In addition, C2s and T1s-CL showed the same absolute change (Δ|0.8|°). The mean values of T1s-CL of the mismatch and balance groups were 23.0° and 7.6°, respectively. The five factors with the largest differences between the two groups were as follows : C2s (Δ13.3°), T1s-CL (Δ15.4°), O-C2A (Δ8.7°), C2-7A (Δ14.7°), and segmental angle (Δ7.9°) before surgery. Only four factors showed statistically significant change between the two groups after ACDF : T1s-CL (Δ4.0° vs. Δ0.2°), C2s (Δ3.2° vs. Δ0.7°), O-C2A (Δ2.6° vs. Δ1.3°), C2-7A (Δ6.3° vs. Δ1.3°). A very strong correlation between T1s-CL and C2s was also found (r=|0.88–0.96|).
Conclusion C2s itself may be the essential key to represent T1s-CL. The amounts and directions of change of these two factors (T1s-CL and C2s) were also almost identical. The above phenomenon was re-confirmed once again through the correlation analysis.
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Affiliation(s)
- Ho Jin Lee
- Department of Neurosurgery, St. Vincent Hospital, College of Medicine, The Catholic University of Korea, Suwon, Korea
| | - Soon Tae You
- Department of Neurosurgery, St. Vincent Hospital, College of Medicine, The Catholic University of Korea, Suwon, Korea
| | - Jae Hoon Sung
- Department of Neurosurgery, St. Vincent Hospital, College of Medicine, The Catholic University of Korea, Suwon, Korea
| | - Il Sup Kim
- Department of Neurosurgery, St. Vincent Hospital, College of Medicine, The Catholic University of Korea, Suwon, Korea
| | - Jae Taek Hong
- Department of Neurosurgery, Eunpyeong St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea
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Clinical impact of 3-level anterior cervical decompression and fusion (ACDF) on the occipito-atlantoaxial complex: a retrospective study of patients who received a zero-profile anchored spacer versus cage-plate construct. EUROPEAN SPINE JOURNAL : OFFICIAL PUBLICATION OF THE EUROPEAN SPINE SOCIETY, THE EUROPEAN SPINAL DEFORMITY SOCIETY, AND THE EUROPEAN SECTION OF THE CERVICAL SPINE RESEARCH SOCIETY 2021; 30:3656-3665. [PMID: 34453599 DOI: 10.1007/s00586-021-06974-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Revised: 08/06/2021] [Accepted: 08/19/2021] [Indexed: 01/14/2023]
Abstract
PURPOSE To evaluate changes in the sagittal parameters of the occipito-atlantoaxial complex after three-level anterior cervical decompression and fusion (ACDF) and identify the influential factors by comparing ACDF with a zero-profile anchored spacer (ACDF-Z) versus a cage-plate construct (ACDF-P). METHODS The cohort comprised 106 patients who underwent three-level contiguous ACDF-Z or ACDF-P for cervical radiculopathy and/or myelopathy. Standing, flexion, and extension radiographs of cervical spine were obtained preoperatively, and 3 and 12 months postoperatively. The assessed cervical sagittal parameters were the platform angle of the axis, Cobb angle, and range of motion (ROM) of C2⁃7, C0⁃1, and C1⁃2. RESULTS In both the ACDF-Z and ACDF-P groups, the Cobb angle of the upper cervical spine decreased and the C0-1 ROM increased from preoperatively to 3 and 12 months postoperatively (P < 0.01). The alignment restoration was lost at 12 months compared with 3 months in the ACDF-Z group, but not in the ACDF-P group (P < 0.01). The ACDF-P group showed more loss of C2-7 ROM and more compensatory changes in C0-2 ROM than the ACDF-Z group (P < 0.05). CONCLUSION The Cobb angle decreased and ROM increased significantly as compensatory changes of the atlantooccipital or atlantoaxial joint after both types of ACDF, which may accelerate degeneration. The zero-profile anchored spacer had less impact on the occipito-atlantoaxial complex but was worse at maintaining the alignment restoration, which were contrary to the cage-plate construct. Surgeons should be aware of the impact of multi-level ACDFs on the occipito-atlantoaxial complex.
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Tang Y, Zhao W, Liu X, Yu M. Normative values of cervical sagittal alignment according to global spine balance: based on 126 asymptomatic Chinese young adults. EUROPEAN SPINE JOURNAL : OFFICIAL PUBLICATION OF THE EUROPEAN SPINE SOCIETY, THE EUROPEAN SPINAL DEFORMITY SOCIETY, AND THE EUROPEAN SECTION OF THE CERVICAL SPINE RESEARCH SOCIETY 2021; 30:2427-2433. [PMID: 34414472 DOI: 10.1007/s00586-021-06756-w] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2020] [Revised: 01/09/2021] [Accepted: 01/26/2021] [Indexed: 11/26/2022]
Abstract
PURPOSE To explore the normal distribution of cervical sagittal alignment and the relationship between cervical alignment and global spine balance in asymptomatic young adults. METHODS A total of 67 males and 59 females aged from 18 to 30 years old were recruited from 11/2011 to 12/2014. The C0-C2 angle, disk angles from C2-C3 to C6-C7, vertebral angles from C3 to C7, T1 slope, thoracic kyphosis (TK), lumbar lordosis, pelvic incidence, sacral slope, C2-C7 sagittal vertical axis (SVA), center of gravity of head to C7 SVA (CGH-C7SVA), C7-S1SVA were measured and statistically analyzed. The Roussouly classification was utilized. RESULTS Mean value of C0-C7 was 26.0° ± 12.8°, composed of 15.2° ± 6.7° for C0-C2, 9.1° ± 12.1° for sum of disk angles from C2-C3 to C6-C7, and 1.4° ± 10.2° for sum of vertebral angles from C3 to C7. C2-C7SVA (18.6 mm ± 7.9 mm) and CGH-C7SVA (22.9 mm ± 12.3 mm) were offset ideally by C7-S1SVA (-21.6 mm ± 31.0 mm). Significant difference was found between cervical alignment of different Roussouly types (p < 0.01). There was significant correlation between cervical alignment and T1 slope (p < 0.01), TK (p < 0.01). There was significant correlation between adjacent segmental angles from T1 slope up to C0-C2 angle (p < 0.05). CONCLUSION Normative values of each vertebral angle and disk angle were established. The cervical lordosis occurred mainly at C0-C2 and disk levels, which was influenced by parameters of other parts of the spine, such as T1 slope, TK and the Roussouly classification. There was significant correlation between adjacent disk angles. LEVEL OF EVIDENCE I Diagnostic: individual cross-sectional studies with the consistently applied reference standard and blinding.
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Affiliation(s)
- Yanchao Tang
- Department of Orthopaedics, Peking University Third Hospital, 49 North Garden Street, HaiDian District, Beijing, 100191, China
- Beijing Key Laboratory of Spinal Disease Research and Engineering, Beijing, China
- Research Center of Bone and Joint Precision Medicine, Ministry of Education, Beijing, China
| | - Wenkui Zhao
- Pain Medicine Center of Peking University Third Hospital, Beijing, China
| | - Xiaoguang Liu
- Department of Orthopaedics, Peking University Third Hospital, 49 North Garden Street, HaiDian District, Beijing, 100191, China
- Beijing Key Laboratory of Spinal Disease Research and Engineering, Beijing, China
- Research Center of Bone and Joint Precision Medicine, Ministry of Education, Beijing, China
- Pain Medicine Center of Peking University Third Hospital, Beijing, China
| | - Miao Yu
- Department of Orthopaedics, Peking University Third Hospital, 49 North Garden Street, HaiDian District, Beijing, 100191, China.
- Beijing Key Laboratory of Spinal Disease Research and Engineering, Beijing, China.
- Research Center of Bone and Joint Precision Medicine, Ministry of Education, Beijing, China.
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Lee HJ, Kim IS, Hong JT. Physiologic Cervical Alignment Change between Cervical Spine X-ray and Computed Tomography. J Korean Neurosurg Soc 2021; 64:784-790. [PMID: 34315198 PMCID: PMC8435648 DOI: 10.3340/jkns.2020.0320] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Accepted: 01/13/2021] [Indexed: 11/27/2022] Open
Abstract
Objective The purpose of this study was to investigate the correlations among various radiological parameters used to determine cervical alignment from cervical spine radiographs (X-CS) and cervical spine computed tomography (CT-CS), both within and between modalities.
Methods This study included 168 patients (≤60 years old) without a definite whole spine deformity who underwent CT-CS and X-CS. We measured occipital slope (O-s), C1 slope, C2 slope, C7 slope, sella turcica - C7 sagittal vertical axis (StC7-SVA), spinocranial angle, T1 slope, and C27-SVA. We calculated the O-C2 angle, O-C7 angle, and C2-7 angle from the measured parameters and conducted correlation analyses among multiple parameters.
Results The intrinsic correlation features among multiple cervical parameters were very similar for both X-CS and CT-CS. The two SVA parameters (C27-SVA and StC7-SVA) were mainly influenced by the upper cervical slope parameters (r=|0.13–0.74|) rather than the lower slope cervical parameters (r=|0.08–0.13|). The correlation between X-CS and CT-CS for each radiological parameter was statistically significant (r=0.26–0.44) except for O-s (r=0.10) and StC7-SVA (r=0.11).
Conclusion The correlation patterns within X-CS and CT-CS were very similar in this study. The correlation between X-ray and CT was statistically significant for most radiological parameters, and the correlation score increased when the horizontal gaze was consistently maintained. The lower cervical parameters were not statistically associated with translation-related parameters (C2-7 SVA and StC7-SVA). Therefore, the upper cervical segment may be a better predictor for determining head and neck translation.
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Affiliation(s)
- Ho Jin Lee
- Department of Neurosurgery, St. Vincent Hospital, College of Medicine, The Catholic University of Korea, Suwon, Korea
| | - Il Sup Kim
- Department of Neurosurgery, St. Vincent Hospital, College of Medicine, The Catholic University of Korea, Suwon, Korea
| | - Jae Taek Hong
- Department of Neurosurgery, Eunpyeong St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea
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Wang X, Meng Y, Liu H, Chen H, Wang B, Hong Y. Association of cervical sagittal alignment with adjacent segment degeneration and heterotopic ossification following cervical disc replacement with Prestige-LP disc. J Orthop Surg (Hong Kong) 2021; 28:2309499020968295. [PMID: 33169634 DOI: 10.1177/2309499020968295] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
PURPOSE Cervical sagittal balance plays important roles in transmitting the load of the head and maintaining global spinal balance. This study aimed to identify the association of cervical sagittal alignment with adjacent segment degeneration (ASD) and heterotopic ossification (HO) after Prestige-LP cervical disc replacement (CDR). METHODS We enrolled 132 patients who underwent one-level Prestige-LP CDR with 2-10 years of follow-up. Cervical sagittal alignment parameters, including the degree of C2-C7 lordosis (CL), functional spinal unit angle (FSUA), sagittal vertical axis (SVA),, and T1 slope (T1s), were measured. ASD and HO were evaluated at the last follow-up. Unpaired t tests and logistic regression analysis were used to identify the associations of cervical sagittal alignment with ASD and HO. RESULTS We found that patients who developed ASD showed significantly lower FSUA (2.1° vs. -1.4°, p < 0.001) and T1s values (28.4° vs. 25.5°, p = 0.029) after surgery. Similarly, the postoperative CL was significantly better in patients without ASD or HO (18.0° vs. 14.4°, p = 0.043). The decrease in the T1s at the last follow-up was significantly larger in the patients with ASD (-11.0° vs. -3.2°, p = 0.003), HO (-6.7° vs. -2.7°, p = 0.050), and ASD or HO (-7.0° vs. -0.8°, p < 0.001) than in those without ASD or HO. Multivariate logistic regression analysis showed that both the FSUA and T1s are associated with ASD and that the degree of CL is associated with postoperative complications. CONCLUSION The results imply that maintaining cervical sagittal alignment after Prestige-LP CDR is important.
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Affiliation(s)
- Xiaofei Wang
- Department of Orthopaedic Surgery, West China Hospital, Sichuan University, Sichuan, China
| | - Yang Meng
- Department of Orthopaedic Surgery, West China Hospital, Sichuan University, Sichuan, China
| | - Hao Liu
- Department of Orthopaedic Surgery, West China Hospital, Sichuan University, Sichuan, China
| | - Hua Chen
- Department of Orthopaedic Surgery, West China Hospital, Sichuan University, Sichuan, China
| | - Beiyu Wang
- Department of Orthopaedic Surgery, West China Hospital, Sichuan University, Sichuan, China
| | - Ying Hong
- Department of Operation Room, West China Hospital, Sichuan University, Sichuan, China.,West China School of Nursing, Sichuan University, Sichuan, China
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Wang Z, Xu JX, Liu Z, Li RY, Wang ZW, Chang HR, Ding WY, Yang DL. Spino cranial angle as a predictor of loss of cervical lordosis after laminoplasty in patients with cervical myelopathy. BMC Surg 2021; 21:291. [PMID: 34118924 PMCID: PMC8199803 DOI: 10.1186/s12893-021-01293-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Accepted: 06/07/2021] [Indexed: 01/24/2023] Open
Abstract
Background To explore the relationship between spino cranial angle (SCA) and loss of cervical lordosis (LOCL), and to determine whether SCA has the ability to predict LOCL for patients with cervical myelopathy. Methods A total of 68 consecutive patients with cervical myelopathy who received laminoplasty (LAMP) were selected to the current study. C2–C7 lordosis was defined as a representation of the cervical alignment. Alignment change > 0° was considered LOCL. Multiple linear regression analysis was applied to evaluate the association between LOCL and various sagittal parameters at preoperative, such as SCA, CL, T1s and cSVA. Linear regression analysis was applied to evaluate the relationships between LOCL and preoperative SCA in each subgroup. Results Patients were assigned to three groups depending on the quartile of preoperative SCA. The first quarter of patients were defined as the low SCA group, the last quarter were defined as the high SCA group and the middle half were defined as the middle SCA group. There was no statistically significant difference in age, sex and the type of OPLL among the three groups. Patients in the low SCA group showed more cervical lordosis before surgery and more LOCL after LAMP (p < 0.001). After linear regression analysis for SCA and LOCL, preoperative SCA was negatively correlated with LOCL in the low SCA group (r = − 0.857, p < 0.001) and high SCA group (r = − 0.515, p = 0.034). However, there was no significant correlation between preoperative SCA and LOCL in the middle SCA group (r = 0.027, p = 0.881). Conclusions Patients with lower SCA had more lordosis preoperatively and performed more LOCL after LAMP at 2 years of follow-up. Both too high or low preoperative SCA were negatively correlated with the degree of LOCL, while when the SCA fluctuates in a suitable range, it is easier to compensate for the changes of cervical sagittal alignment.
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Affiliation(s)
- Zheng Wang
- Department of Spinal Surgery, The Third Hospital of Hebei Medical University, 139 Ziqiang Road, Shijiazhuang, 050051, People's Republic of China
| | - Jia-Xin Xu
- Department of Spinal Surgery, The Third Hospital of Hebei Medical University, 139 Ziqiang Road, Shijiazhuang, 050051, People's Republic of China
| | - Zhen Liu
- Department of Spinal Surgery, The Third Hospital of Hebei Medical University, 139 Ziqiang Road, Shijiazhuang, 050051, People's Republic of China
| | - Ruo-Yu Li
- Department of Spinal Surgery, The Third Hospital of Hebei Medical University, 139 Ziqiang Road, Shijiazhuang, 050051, People's Republic of China
| | - Zhi-Wei Wang
- Department of Spinal Surgery, The Third Hospital of Hebei Medical University, 139 Ziqiang Road, Shijiazhuang, 050051, People's Republic of China
| | - Heng-Rui Chang
- Department of Spinal Surgery, The Third Hospital of Hebei Medical University, 139 Ziqiang Road, Shijiazhuang, 050051, People's Republic of China
| | - Wen-Yuan Ding
- Department of Spinal Surgery, The Third Hospital of Hebei Medical University, 139 Ziqiang Road, Shijiazhuang, 050051, People's Republic of China
| | - Da-Long Yang
- Department of Spinal Surgery, The Third Hospital of Hebei Medical University, 139 Ziqiang Road, Shijiazhuang, 050051, People's Republic of China.
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Park EJ, Chung S, Min WK. Reciprocal change of occipitocervical parameters after anterior cervical discectomy and fusion. Sci Rep 2021; 11:5744. [PMID: 33707621 PMCID: PMC7952897 DOI: 10.1038/s41598-021-85189-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2020] [Accepted: 02/23/2021] [Indexed: 12/03/2022] Open
Abstract
To evaluate the reciprocal changes in occipitocervical parameters according to the recovery of cervical lordosis (CL) after anterior cervical discectomy and fusion (ACDF) in patients with sagittal imbalance. Sixty-five cases that underwent ACDF were followed. They were divided according to the recovery of the CL: Group 1 (ΔCL > 5°, 30 cases) and Group 2 (ΔCL < 5°, 35 cases). The following parameters were measured: occiput-cervical inclination (OCI), CL, occiput-C2 angle (OC2A), distance between external occipital protuberance and spinous process of C2 (OC2D), distance between spinous processes of C2 and C7 (C27D), and shortest distance between the plumb line of C2 body and posterosuperior corner of C7 (C27SVA). Overall, all parameters changed significantly after ACDF. Preoperative CL and preoperative C27D showed a correlation with ΔCL. ΔCL was negatively correlated with ΔC27D and ΔC27SVA. In Group 1, CL increased from − 2.60 ± 1.88° to 11.57 ± 1.83°, OC2A decreased from 23.96 ± 2.05° to 19.87 ± 1.36°, OC2D increased from 82.96 ± 1.48 mm to 86.50 ± 1.81 mm, C27D decreased from 95.61 ± 2.66 mm to 87.01 ± 2.50 mm, and C27SVA decreased from 24.14 ± 2.20 mm to 17.06 ± 2.14 mm. In Group 2, only OCI decreased significantly after ACDF. ACDF can increase CL postoperatively in patients with cervical sagittal imbalance. Patients with significant CL recovery after ACDF showed a reciprocal change in occipitocervical parameters. (OC2A, OC2D).
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Affiliation(s)
- Eugene J Park
- Department of Orthopedic Surgery, Kyungpook National University Hospital, Kyungpook National University School of Medicine, (41944) 130 Dongdeok-ro, Jung-gu, Daegu, Republic of Korea
| | - Seungho Chung
- Department of Orthopedic Surgery, Kyungpook National University Hospital, Kyungpook National University School of Medicine, (41944) 130 Dongdeok-ro, Jung-gu, Daegu, Republic of Korea
| | - Woo-Kie Min
- Department of Orthopedic Surgery, Kyungpook National University Hospital, Kyungpook National University School of Medicine, (41944) 130 Dongdeok-ro, Jung-gu, Daegu, Republic of Korea.
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Lee SH, Hyun SJ, Jain A. Cervical Sagittal Alignment: Literature Review and Future Directions. Neurospine 2020; 17:478-496. [PMID: 33022153 PMCID: PMC7538362 DOI: 10.14245/ns.2040392.196] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Accepted: 08/13/2020] [Indexed: 12/26/2022] Open
Abstract
Cervical alignment as a concept has come to the forefront for spine deformity research in the last decade. Studies on cervical sagittal alignment started from normative data, and expanded into correlation with global sagittal balance, prognosis of various conditions, outcomes of surgery, definition and classification of cervical deformity, and prediction of targets for ideal cervical reconstruction. Despite the recent robust research efforts, the definition of normal cervical sagittal alignment and cervical spine deformity continues to elude us. Further, many studies continue to view cervical alignment as a continuation of thoracolumbar deformity and do not take into account biomechanical features unique to the cervical spine that may influence cervical alignment, such as the importance of musculature connecting cranium-cervical-thoracic spine and upper extremities. In this article, we aim to summarize the relevant literature on cervical sagittal alignment, discuss key results, and list potential future direction for research using the '5W1H' framework; "WHO" are related?, "WHY" important?, "WHAT" to evaluate and "WHAT" is normal?, "HOW" to evaluate?, "WHEN" to apply sagittal balance?, and "WHERE" to go in the future?
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Affiliation(s)
- Sang Hun Lee
- Department of Orthopaedic Surgery, Johns Hopkins University, School of Medicine, Baltimore, MD, USA
| | - Seung-Jae Hyun
- Department of Neurological Surgery, Seoul National University College of Medicine, Seoul, Korea
| | - Amit Jain
- Department of Orthopaedic Surgery, Johns Hopkins University, School of Medicine, Baltimore, MD, USA
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Ma J, Cheng Z, Jiang Z, Yuan J, Wang W, Long M, Zhang X. [Correlation analysis between C 7 slope and cervical sagittal parameters in short segment anterior cervical discectomy with fusion]. ZHONGGUO XIU FU CHONG JIAN WAI KE ZA ZHI = ZHONGGUO XIUFU CHONGJIAN WAIKE ZAZHI = CHINESE JOURNAL OF REPARATIVE AND RECONSTRUCTIVE SURGERY 2019; 33:877-882. [PMID: 31298007 PMCID: PMC8337420 DOI: 10.7507/1002-1892.201901065] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 01/14/2019] [Revised: 05/20/2019] [Indexed: 11/03/2022]
Abstract
OBJECTIVE To elucidate the relationship between preoperative C 7 slope (C 7S) and sagittal parameters in anterior cervical discectomy with fusion (ACDF) by imaging. METHODS A retrospective analysis of 54 patients (24 males and 30 females) with ACDF for cervical spondylosis between January 2012 and January 2017 was performed. The age ranged from 23 to 71 years (mean, 46.6 years). There were 29 cases of cervical spondylotic radiculopathy and 25 cases of cervical spondylotic myelopathy. The disease duration ranged from 3 to 48 months, with an average of 16.8 months. In the 55 patients, 44 were single-segment ACDF and 10 were double-segment ACDF. Sagittal parameters of cervical spine were measured on cervical X-ray films before operation and at last follow-up, including C 2-7 Cobb angle, C 2-7 sagittal vertical axis (C 2-7 SVA), C 7S, and segment Cobb angle (SCobb), and the changes of C 2-7 Cobb angle (the difference between the last follow-up and the preoperative angle) were calculated. Pearson correlation was used to analyze the correlation between the parameters before operation and at last follow-up. According to the preoperative median value of C 7S (15°), the patients were divided into group A (C 7S<15°) and group B (C 7S≥15°). The sagittal parameters before and after operation were compared between the two groups. RESULTS All the 54 patients were followed up 6-45 months (mean, 15.5 months). At last follow-up, C 7S, C 2-7 Cobb angle, C 2-7 SVA, and SCobb angle were significantly improved when compared with preoperative values ( P<0.05). Correlation analysis showed that the preoperative C 7S and SCobb angles were significantly correlated with C 2-7 Cobb angle and C 2-7 SVA ( P<0.05), but there was no significant correlation between C 7S and SCobb angle ( r=0.049, P=0.724). There was a significant correlation between C 7S, C 2-7 Cobb angle, and SCobb angle at last follow-up ( P<0.05), but there was no significant correlation between C 7S and SCobb angles and C 2-7 SVA ( P>0.05). According to the median value of preoperative C 7S, 28 patients in group A had C 7S of (11.82±3.60)°, while 26 patients in group B had C 7S of (20.77±4.09)°. There was no significant difference in gender and age between the two groups ( P>0.05). The preoperative C 2-7 Cobb angle and C 2-7 SVA in group A were significantly lower than those in group B ( P<0.05). There was no significant difference between preoperative SCobb angle and group B ( t=0.234, P=0.816). There were no significant differences in C 2-7 Cobb angle, C 2-7 SVA, and SCobb angle between group A and group B at last follow-up ( P>0.05). However, the change of C 2-7 Cobb angle in group A was significantly higher than that in group B ( t=2.321, P=0.024). CONCLUSION Preoperative C 7S≥15° group has more physiological lordosis before operation, but its postoperative cervical curvature changes less, while ACDF is more conducive to correct the preoperative C 7S<15 ° cervical curvature.
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Affiliation(s)
- Junfeng Ma
- Graduate School of Tianjin Medical University, Tianjin, 300070, P.R.China;Department of Spinal Surgery, Tianjin Union Medical Center, Tianjin, 300121, P.R.China
| | - Zhaojun Cheng
- Tianjin Universtity of Traditional Chinese Medicine, Tianjin, 300193, P.R.China
| | - Zehua Jiang
- Department of Spinal Surgery, Tianjin Union Medical Center, Tianjin, 300121, P.R.China
| | - Jianjun Yuan
- Department of Spinal Surgery, Tianjin Union Medical Center, Tianjin, 300121, P.R.China
| | - Wei Wang
- Graduate School of Tianjin Medical University, Tianjin, 300070, P.R.China
| | - Mingxing Long
- Graduate School of Tianjin Medical University, Tianjin, 300070, P.R.China
| | - Xueli Zhang
- Department of Spinal Surgery, Tianjin Union Medical Center, Tianjin, 300121,
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Affiliation(s)
- Jae Taek Hong
- Department of Neurosurgery, Eunpyeong St. Mary's Hospital, The Catholic University of Korea, 1021 Tongil-ro, Eunpyeong-gu, Seoul 03312, Korea
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Basques BA, Louie PK, Mormol J, Khan JM, Movassaghi K, Paul JC, Varthi A, Goldberg EJ, An HS. Multi- versus single-level anterior cervical discectomy and fusion: comparing sagittal alignment, early adjacent segment degeneration, and clinical outcomes. EUROPEAN SPINE JOURNAL : OFFICIAL PUBLICATION OF THE EUROPEAN SPINE SOCIETY, THE EUROPEAN SPINAL DEFORMITY SOCIETY, AND THE EUROPEAN SECTION OF THE CERVICAL SPINE RESEARCH SOCIETY 2018; 27:2745-2753. [PMID: 29946938 DOI: 10.1007/s00586-018-5677-y] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2018] [Revised: 06/05/2018] [Accepted: 06/19/2018] [Indexed: 12/31/2022]
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Siasios I, Winograd E, Khan A, Vakharia K, Dimopoulos VG, Pollina J. Cervical sagittal balance parameters after single-level anterior cervical discectomy and fusion: Correlations with clinical and functional outcomes. JOURNAL OF CRANIOVERTEBRAL JUNCTION AND SPINE 2018; 9:56-62. [PMID: 29755238 PMCID: PMC5934966 DOI: 10.4103/jcvjs.jcvjs_9_18] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Abstract
Background: Normal sagittal cervical alignment has been associated with improved outcome after anterior cervical discectomy and fusion (ACDF). Objective: The aim of this study is to identify alterations of cervical sagittal balance parameters after single-level ACDF and assess correlations with postoperative functionality. Methods: A retrospective chart review was performed between January 2010 and January 2014 to identify adult patients with no previous cervical spine surgery who underwent ACDF at any one level between C2 and C7 for the single-level degenerative disease. Tumor, infection, and trauma cases were excluded from the study. For the included cases, the following data were recorded preoperatively and 6 months–1 year after surgery: sagittal balance-marker measurements of the C1–C2 angle, C2–C7 angle, C7 slope, segmental angle at the operated level, and sagittal vertical axis (SVA) distance between C2 and C7, as well as the neck disability index and visual analog scale of pain. Results: The present study included 47 patients (average age: 51.2 years; range: 28–86 years). A moderate negative correlation between a smaller C2–C7 angle and the presence of right arm pain before treatment was found (P = 0.0281). Postoperatively, functionality scores significantly improved in all patients. C1–C2 angle increased with statistical significance (P = 0.0255). C2–C7 angle, segmental angle, C7 slope, and SVA C2–C7 distance did not change with statistical significance after surgery. C7 slope significantly correlated with overall cervical sagittal balance (P < 0.05). Conclusions: Single-level ACDF significantly increases upper cervical lordosis (C1–C2) without significantly changing lower cervical lordosis (C2–C7). The C7 slope is a significant marker of overall cervical sagittal alignment (P < 0.05).
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Affiliation(s)
- Ioannis Siasios
- Department of Neurosurgery, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, State University of New York, USA.,Department of Neurosurgery, Kaleida Health, Buffalo, New York, USA
| | - Evan Winograd
- Department of Neurosurgery, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, State University of New York, USA.,Department of Neurosurgery, Kaleida Health, Buffalo, New York, USA
| | - Asham Khan
- Department of Neurosurgery, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, State University of New York, USA.,Department of Neurosurgery, Kaleida Health, Buffalo, New York, USA
| | - Kunal Vakharia
- Department of Neurosurgery, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, State University of New York, USA.,Department of Neurosurgery, Kaleida Health, Buffalo, New York, USA
| | - Vassilios G Dimopoulos
- Department of Neurosurgery, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, State University of New York, USA.,Department of Neurosurgery, Kaleida Health, Buffalo, New York, USA
| | - John Pollina
- Department of Neurosurgery, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, State University of New York, USA.,Department of Neurosurgery, Kaleida Health, Buffalo, New York, USA
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Smith-Robinson procedure with and without Caspar plating as a treatment for cervical spondylotic myelopathy: A 26-year follow-up of 23 patients. EUROPEAN SPINE JOURNAL : OFFICIAL PUBLICATION OF THE EUROPEAN SPINE SOCIETY, THE EUROPEAN SPINAL DEFORMITY SOCIETY, AND THE EUROPEAN SECTION OF THE CERVICAL SPINE RESEARCH SOCIETY 2017; 26:1246-1253. [PMID: 28185064 DOI: 10.1007/s00586-017-4988-8] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2016] [Revised: 01/18/2017] [Accepted: 01/31/2017] [Indexed: 12/15/2022]
Abstract
PURPOSE The purpose of this study was to assess long-term follow-up data after anterior cervical decompression and fusion (ACDF) with and without Caspar plating (ACDF + PS) for the treatment of cervical spondylotic myelopathy (CSM) with special focus on functional outcome, pain, and repeat surgery for adjacent segment disease (ASD). METHOD Hospital records of 45 patients who were affected by CSM and underwent ACDF or ACDF + PS at least 17 years ago were reviewed. Information about diagnosis, surgical report, pre- and postoperative clinical process, and complications was analyzed. Clinical outcome was assessed using a standardized questionnaire including the Neck Disability Index (NDI), modified JOA-score, Odom's criteria, limitations in quality of life, and questions about the current neurological status and pain. RESULTS Twenty-three patients with a mean follow-up of 26 years were evaluated. ACDF was performed in nine and ACDF + PS in 14 patients, respectively. At follow-up 78.3% of patients were free of pain, 91.3% had no motor deficit, 73.9% had no sensory deficit, and 60.7% had no gait disturbance. The current mean NDI is 14% (range 2-44%), the mean modified JOA-score was 17.2 (range 15-18). According to Odom's criteria 78.3% of patients had clinical success. In four patients repeat surgery was indicated due to pseudarthrosis or symptomatic ASD (17.4%). CONCLUSIONS ACDF and ACDF + PS yield significant decrease in neck pain, a significant increase in sensorimotor function and a high rate of clinical success. Patients with preoperative gait disturbance completely recovered in about 60% of cases. Overall prevalence for ASD was 17.4% after 25 years.
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Dejaegher J, Walraevens J, van Loon J, Van Calenbergh F, Demaerel P, Goffin J. 10-year follow-up after implantation of the Bryan Cervical Disc Prosthesis. EUROPEAN SPINE JOURNAL : OFFICIAL PUBLICATION OF THE EUROPEAN SPINE SOCIETY, THE EUROPEAN SPINAL DEFORMITY SOCIETY, AND THE EUROPEAN SECTION OF THE CERVICAL SPINE RESEARCH SOCIETY 2016; 26:1191-1198. [PMID: 27904963 DOI: 10.1007/s00586-016-4897-2] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2016] [Revised: 11/02/2016] [Accepted: 11/23/2016] [Indexed: 12/30/2022]
Abstract
PURPOSE Cervical arthroplasty is being used as an alternative for cervical fusion, but long-term follow-up results have rarely been reported. In this paper, we present 10-year follow-up results after implantation of the Bryan Cervical Disc Prosthesis in a single center. METHODS 89 patients underwent implantation of a single-level Bryan Cervical Disc Prosthesis to treat radiculopathy and/or myelopathy. Clinical (Neurological Success, Neck Disability Index (NDI), Neck- and Arm-Pain, and SF-36) and radiological follow-up was prospectively organized up to 10 years after surgery. Adverse events and second surgeries were recorded and evaluated. RESULTS Ten-year follow-up data were available for 72 (81%) patients. Maintenance or improvement of the neurological state was seen in 89% of patients after 10-year follow-up. SF-36 PCS scores improved significantly at all follow-up points. SF-36 MCS improvement was significant at 4 and 6 year, but not at 8- and 10-year follow-up. Significant improvement for NDI, and Neck- and Arm-Pain scores was found for the subgroup of patients in whom these data were available. Mean angular motion of the prosthesis at 10-year follow-up was 8.6°. Mobility of the device, defined as >2° of angular motion, was reached in 81% of patients. During the study period, 21 patients (24%) developed new or recurrent radiculopathy or myelopathy, the majority of these being treated conservatively. Seven patients (8%) required 8 additional spine surgeries to treat persistent or recurrent symptoms. Of these, 2 patients (2%) were reoperated at the index level and at 5 (6%) an adjacent level. CONCLUSION In this study, favorable long-term clinical outcome after implantation of the Bryan Cervical Disc Prosthesis was seen, with the majority of prostheses remaining mobile after 10-year follow-up. However, still 6% of patients required adjacent level surgery.
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Affiliation(s)
- Joost Dejaegher
- Department of Neurosurgery, University Hospitals Leuven, Leuven, Belgium.
| | | | - Johannes van Loon
- Department of Neurosurgery, University Hospitals Leuven, Leuven, Belgium
| | | | - Philippe Demaerel
- Department of Radiology, University Hospitals Leuven, Leuven, Belgium
| | - Jan Goffin
- Department of Neurosurgery, University Hospitals Leuven, Leuven, Belgium
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