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Pizones J, Hills J, Kelly M, Yilgor C, Moreno-Manzanaro L, Perez-Grueso FJS, Kleinstück F, Obeid I, Alanay A, Pellisé F. Which sagittal plane assessment method is most predictive of complications after adult spinal deformity surgery? Spine Deform 2024:10.1007/s43390-024-00864-5. [PMID: 38607513 DOI: 10.1007/s43390-024-00864-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/14/2023] [Accepted: 03/16/2024] [Indexed: 04/13/2024]
Abstract
PURPOSE Different methods of sagittal alignment assessment compete for predicting adverse events after adult spinal deformity (ASD) surgery. We wanted to study which method provides greater benefit. METHODS Retrospective study of 391 patients operated for ASD, with > 6 instrumented levels, fused to the pelvis, and 2 years of follow-up. Three alignment methods were analyzed 6-week postoperatively: (1) Roussouly mismatch; (2) GAP score/GAP categories; (3) T4-L1-Hip axis. Binary logistic regression generated models that best predict the following adverse events: mechanical complications (MC): in general and isolated (PJK, PJF, rod breakage); reinterventions (in general and after MC); and readmissions. ROC/AUC analysis was also implemented. In a second regression round, we added different variables that were selected on univariate analysis-demographic, surgical, and radiographic-to complete the models. RESULTS The best predictor parameters in most models were T4-L1PA mismatch and GAP score; we could not prove a predictive ability of the Roussouly mismatch. The T4-L1PA mismatch best predicted general MC, PJK, PJK + PJF, and readmission, while the GAP score best predicted PJF and reinterventions (for MC and for any complication). However, the variance explained by these models was limited (Nagelkerke's R2 = 0.031-0.113), with odds ratios ranging from 1.070 to 1.456. ROC curves plotted an AUC between 0.57 and 0.70. Introducing additional variables (demographic, surgical, and radiographic) improved prediction in all the models (Nagelkerke's R2 = 0.082-0.329) and allowed predicting rod breakage. CONCLUSION The T4-L1-Hip axis and GAP score show potential in predicting adverse events, surpassing the Roussouly method. Despite partial efficacy in complication anticipation, recognizing postoperative sagittal alignment as a key modifiable risk factor, the crucial need arises to integrate diverse variables, both modifiable and non-modifiable, for enhanced predictive accuracy. LEVEL OF EVIDENCE Level IV.
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Affiliation(s)
- Javier Pizones
- Spine Unit, Department of Orthopedic Surgery, Hospital Universitario La Paz, Paseo de la Castellana 261, 28046, Madrid, Spain.
| | | | - Michael Kelly
- Rady Children Hospital San Diego, University of California, San Diego, CA, USA
| | - Caglar Yilgor
- Department of Orthopedics and Traumatology, Acibadem Mehmet Ali Aydinlar University, Istanbul, Turkey
| | - Lucía Moreno-Manzanaro
- Spine Unit, Department of Orthopedic Surgery, Hospital Universitario La Paz, Paseo de la Castellana 261, 28046, Madrid, Spain
| | | | - Frank Kleinstück
- Department of Orthopedics, Schulthess Klinik, Zurich, Switzerland
| | - Ibrahim Obeid
- Spine Surgery Unit, Pellegrin University Hospital, Bordeaux, France
| | - Ahmet Alanay
- Department of Orthopedics and Traumatology, Acibadem Mehmet Ali Aydinlar University, Istanbul, Turkey
| | - Ferran Pellisé
- Spine Surgery Unit, Hospital Universitario Vall d'Hebron, Barcelona, Spain
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Raganato R, Gómez-Rice A, Moreno-Manzanaro L, Escámez F, Talavera G, Aguilar A, Sánchez-Márquez JM, Fernández-Baíllo N, Perez-Grueso FJS, Kleinstück F, Alanay A, Obeid I, Pellisé F, Pizones J. What factors are associated with a better restoration of pelvic version after adult spinal deformity surgery? Spine Deform 2024:10.1007/s43390-024-00863-6. [PMID: 38589595 DOI: 10.1007/s43390-024-00863-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/10/2023] [Accepted: 03/13/2024] [Indexed: 04/10/2024]
Abstract
INTRODUCTION Poor restoration of pelvic version after adult spinal deformity (ASD) surgery is associated with an increased risk of mechanical complications and worse quality of life. We studied the factors linked to the improvement of postoperative pelvic version. MATERIALS AND METHODS This is a retrospective analysis of a prospective multicenter ASD database. Selection criteria were: operated patients having preoperative severe pelvic retroversion as per GAP score (Relative Pelvic Version-RPV < - 15°); panlumbar fusions to the pelvis; 2-year follow-up. Group A comprised patients with any postoperative improvement of RPV score, and group B had no improvement. Groups were compared regarding baseline characteristics, surgical factors, and postoperative sagittal parameters. Parametric and non-parametric analyses were employed. RESULTS 177 patients were studied, median age 67 years (61; 72.5), 83.6% female. Groups were homogeneous in baseline demographics, comorbidities, and preoperative sagittal parameters (p > 0.05). The difference in RPV improvement was 11.56º. Group A (137 patients) underwent a higher percentage of ALIF procedures (OR = 6.66; p = 0.049), and posterior osteotomies (OR = 4.96; p < 0.001) especially tricolumnar (OR = 2.31; p = 0.041). It also showed a lower percentage of TLIF procedures (OR = 0.45; p = 0.028), and posterior decompression (OR = 0.44; p = 0.024). Group A displayed better postoperative L4-S1 angle and relative lumbar lordosis (RLL), leading to improved sacral slope (and RPV), and global alignment (RSA). Group A patients had longer instrumentations (11.45 vs 10; p = 0.047) and hospitalization time (13 vs 11; p = 0.045). All postoperative sagittal parameters remained significantly better in group A through follow-up. However, differences between the groups narrowed over time. CONCLUSIONS ALIF procedures and posterior column osteotomies improved pelvic version postoperatively, and associated better L4-S1 and lumbar lordosis restoration, indirectly improving all other sagittal parameters. However, these improvements seemed to fade during the 2-year follow-up.
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Affiliation(s)
- Riccardo Raganato
- Spine Unit, Department of Orthopedic Surgery, Hospital Universitario La Paz, Paseo de la Castellana 261, 28046, Madrid, Spain
- Spine Research Unit, Vall d'Hebron Institute of Research, Barcelona, Spain
| | - Alejandro Gómez-Rice
- Spine Unit, Department of Orthopedic Surgery, Hospital Universitario Ramón y Cajal, Madrid, Spain
- Spine Research Unit, Vall d'Hebron Institute of Research, Barcelona, Spain
| | - Lucía Moreno-Manzanaro
- Spine Unit, Department of Orthopedic Surgery, Hospital Universitario La Paz, Paseo de la Castellana 261, 28046, Madrid, Spain
- Spine Research Unit, Vall d'Hebron Institute of Research, Barcelona, Spain
| | - Fernando Escámez
- Spine Unit, Department of Orthopedic Surgery, Hospital Universitario La Paz, Paseo de la Castellana 261, 28046, Madrid, Spain
- Spine Research Unit, Vall d'Hebron Institute of Research, Barcelona, Spain
| | - Gloria Talavera
- Spine Unit, Department of Orthopedic Surgery, Hospital Universitario La Paz, Paseo de la Castellana 261, 28046, Madrid, Spain
- Spine Research Unit, Vall d'Hebron Institute of Research, Barcelona, Spain
| | - Antonio Aguilar
- Department of Orthopedic Surgery, Hospital Virgen de las Nieves, Granada, Spain
- Spine Research Unit, Vall d'Hebron Institute of Research, Barcelona, Spain
| | - José Miguel Sánchez-Márquez
- Spine Unit, Department of Orthopedic Surgery, Hospital Universitario La Paz, Paseo de la Castellana 261, 28046, Madrid, Spain
- Spine Research Unit, Vall d'Hebron Institute of Research, Barcelona, Spain
| | - Nicomedes Fernández-Baíllo
- Spine Unit, Department of Orthopedic Surgery, Hospital Universitario La Paz, Paseo de la Castellana 261, 28046, Madrid, Spain
- Spine Research Unit, Vall d'Hebron Institute of Research, Barcelona, Spain
| | - Francisco Javier Sánchez Perez-Grueso
- Spine Unit, Department of Orthopedic Surgery, Hospital Universitario La Paz, Paseo de la Castellana 261, 28046, Madrid, Spain
- Spine Research Unit, Vall d'Hebron Institute of Research, Barcelona, Spain
| | - Frank Kleinstück
- Department of Orthopedics, Schulthess Klinik, Zurich, Switzerland
- Spine Research Unit, Vall d'Hebron Institute of Research, Barcelona, Spain
| | - Ahmet Alanay
- Department of Orthopedics and Traumatology, Acibadem Mehmet Ali Aydinlar University, Istanbul, Turkey
- Spine Research Unit, Vall d'Hebron Institute of Research, Barcelona, Spain
| | - Ibrahim Obeid
- Spine Surgery Unit, Pellegrin University Hospital, Bordeaux, France
- Spine Research Unit, Vall d'Hebron Institute of Research, Barcelona, Spain
| | - Ferran Pellisé
- Spine Surgery Unit, Hospital Universitario Vall d'Hebron, Barcelona, Spain
- Spine Research Unit, Vall d'Hebron Institute of Research, Barcelona, Spain
| | - Javier Pizones
- Spine Unit, Department of Orthopedic Surgery, Hospital Universitario La Paz, Paseo de la Castellana 261, 28046, Madrid, Spain.
- Spine Research Unit, Vall d'Hebron Institute of Research, Barcelona, Spain.
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Gessara A, Patel MS, Estefan M, Koch JEJ, Gutman N, Mardashti A, Shetaiwi A, Quraishi NA. Restoration of the sagittal profile according to the Roussouly classification reduces mechanical complications and revision surgery in older patients undergoing surgery for adult spinal deformity (ASD). Eur Spine J 2024; 33:563-570. [PMID: 37768339 DOI: 10.1007/s00586-023-07885-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2023] [Revised: 07/14/2023] [Accepted: 08/04/2023] [Indexed: 09/29/2023]
Abstract
PURPOSE The mechanical complications related to ASD remain a concern due to their morbidity and associated revision surgery. Restoration of each patient's Roussouly profile may reduce these. Our aim was to examine if the restoration of the Roussouly profile reduced these complications and revision rates in older patients operated for degenerative ASD. METHODS Retrospective analysis of a single-centre, 2-year minimum follow-up patient database. All patients undergoing corrective surgery (≥ 4 levels) for ASD were included with analysis of demographic data, operative records, restoration of Roussouly sagittal profile, mechanical complications and revision rates. Univariate and multivariate analysis was conducted. RESULTS Fifty-two patients were included (mean age was 72.3 years, average follow-up 56.3 months). Twenty-six patients had a "restored" profile (50%) and 26 an "unrestored" profile (50%). The incidence of mechanical complications was 7 (27%) and 23 (88%) for the restored and unrestored groups, respectively (p < 0.001). Revision rates were 4 (15.4%) and 18 (69.2%), respectively (p < 0.000), in the restored and unrestored profiles. Univariate analysis determined that profile restoration and BMI were associated with mechanical complications and revision surgery, whilst only the profile restoration status maintained its statistical power in multivariate analysis (p = 0.002 and p = 0.002, respectively). Age was not a significant factor in univariate analysis. The relative risk for mechanical failure and revision surgery was 5.6 times (CI 1.929-16.39) and 3.08 times (CI 1.642-5.734) greater if the profile was not restored. CONCLUSIONS Achieving each patient's ideal Roussouly profile is associated with a reduced incidence of mechanical complications and revision rates in the older population after surgery for degenerative ASD.
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Affiliation(s)
- Alan Gessara
- Queens Medical Centre, Centre for Spinal Studies and Surgery, Nottingham, UK.
| | | | - Martin Estefan
- Queens Medical Centre, Centre for Spinal Studies and Surgery, Nottingham, UK
| | - Jonathan E J Koch
- Queens Medical Centre, Centre for Spinal Studies and Surgery, Nottingham, UK
| | - Nadav Gutman
- Queens Medical Centre, Centre for Spinal Studies and Surgery, Nottingham, UK
| | - Ali Mardashti
- Queens Medical Centre, Centre for Spinal Studies and Surgery, Nottingham, UK
| | - Ali Shetaiwi
- Queens Medical Centre, Centre for Spinal Studies and Surgery, Nottingham, UK
| | - Nasir Ali Quraishi
- Queens Medical Centre, Centre for Spinal Studies and Surgery, Nottingham, UK
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Pan C, Bourghli A, Larrieu D, Boissiere L, Pizones J, Alanay A, PelIise F, Kleinstück F, Obeid I. Sagittal alignment of diverse mechanical complications following adult spinal deformity surgery. Eur Spine J 2024:10.1007/s00586-023-08126-0. [PMID: 38270602 DOI: 10.1007/s00586-023-08126-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2023] [Revised: 12/22/2023] [Accepted: 12/28/2023] [Indexed: 01/26/2024]
Abstract
PURPOSE To compare the sagittal alignment of patients with diverse mechanical complications (MCs) following adult spinal deformity (ASD) surgery with that of patients without MCs. METHODS A total of 371 patients who underwent ASD surgery were enrolled. The sagittal spinopelvic parameters were measured preoperatively and at the 6-month and last follow-up, and the global alignment and proportion (GAP) score was calculated. The subjects were divided into non-MC and MCs groups, and the MCs group was further divided into rod fracture (RF), screw breakage (SB), screw dislodgement (SD) and proximal junctional kyphosis (PJK) subgroups. RESULTS Preoperatively, the RF group had greater thoracolumbar kyphosis (TLK) and relative upper lumbar lordosis (RULL); the SB group had the largest pelvic incidence (PI) and lumbar lordosis (LL); the SD group had the least global sagittal imbalance; and the PJK group had the highest thoracic kyphosis (TK), TLK and RULL. At the last follow-up, the RF and SB groups featured a large PI minus LL (PI-LL), while the PJK group featured a prominent TK; all the MCs subgroups had sagittal malalignment and a higher GAP score, and the SB group had the most severe cases. Logistic regressions showed that the relative spinopelvic alignment (RSA) score was correlated with RF, SB and SD, while the RSA and age scores were associated with PJK. CONCLUSION Each patient with MCs had individual characteristics in the sagittal plane following ASD surgery, which may be helpful to understand the pathophysiology of poor sagittal alignment with its subsequent MCs and guide an eventual revision strategy.
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Affiliation(s)
- Changyu Pan
- Department of Spine Surgery, The Second Xiangya Hospital of Central South University, Digital Spine Research Institute, Changsha, 410011, Hunan, China.
| | - Anouar Bourghli
- Orthopedic and Spinal Surgery Department, Kingdom Hospital, P.O.Box 84400, 11671, Riyadh, Saudi Arabia
| | - Daniel Larrieu
- Clinique du Dos, Elsan Jean Villar Private Hospital, Bordeaux, France
| | - Louis Boissiere
- Clinique du Dos, Elsan Jean Villar Private Hospital, Bordeaux, France
| | - Javier Pizones
- Spine Surgery Unit, Hospital Universitario La Paz, Madrid, Spain
| | - Ahmet Alanay
- Spine Surgery Unit, Acibadem Maslak Hospital, Istanbul, Turkey
| | - Ferran PelIise
- Spine Surgery Unit, Hospital Universitario Vall Hebron, Barcelona, Spain
| | | | - Ibrahim Obeid
- Clinique du Dos, Elsan Jean Villar Private Hospital, Bordeaux, France
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Prost S, Charles YP, Ilharreborde B, Riouallon G, Pesenti S, Blondel B. Thoracolumbar Sagittal Shape Varies With Pelvic Morphology and Aging. Spine (Phila Pa 1976) 2023; 48:1726-1732. [PMID: 36745431 DOI: 10.1097/brs.0000000000004590] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Accepted: 11/02/2022] [Indexed: 02/07/2023]
Abstract
STUDY DESIGN Retrospective study of a multicenter prospective database. OBJECTIVE The objective of this study was to determine the organization and correlations between different spinal segments according to pelvic incidence (PI) and age. SUMMARY OF BACKGROUND DATA When planning surgery for the correction of adult spinal deformities, considering lumbar lordosis (LL) as a uniform segment is an approximation that can lead to planning errors. MATERIALS AND METHODS Radiographs of 1540 subjects were analyzed and divided into three PI groups: low <45, intermediate 45 to 60, high >60, and stratified by age (<45, 45-70, and >70 yr). The different segments of L1-L4 proximal lumbar lordosis (PLL), L4-S1 distal lumbar lordosis (DLL), and T10-L1 thoracolumbar junction (TLJ) were analyzed. RESULTS The mean age was 53.5 years (SD=17, minimum=20, maximum=93). There was a significant correlation between thoracic kyphosis T5-T12 and TLJ segment T10-L1 ( r =0.581, P <0.001). Only the L1-L4 PLL segment correlated with PI ( r =0.47, P <0.001). The T10-L1 TLJ segment was constant regardless of age or PI groups considered (mean=-8, SD=9). PLL did not vary with aging but differed according to PI. The DLL showed significant differences between age and PI groups but without a significant correlation between PI and DLL. CONCLUSIONS Pelvic morphology is known to determine the curvatures of the spine, however, the distribution of LL is not homogeneous. Our study provided a normative value reference and showed that T10-L1 is constant regardless of age or PI. LEVEL OF EVIDENCE III.
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Affiliation(s)
- Solène Prost
- AIx-Marseille University, APHM, CNRS, ISM, CHU Timone, Spine surgery, Marseille, France
| | | | - Brice Ilharreborde
- Pediatric Orthopedic Department, CHU Robert Debré, Paris University, Paris, France
| | | | - Sébastien Pesenti
- AIx-Marseille University, APHM, CNRS, ISM, CHU Timone, Spine surgery, Marseille, France
| | - Benjamin Blondel
- AIx-Marseille University, APHM, CNRS, ISM, CHU Timone, Spine surgery, Marseille, France
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Li Y, Qian BP, Qiu Y, Yu Y, Wang B. Orientation of Osteotomized Vertebrae in 2-Level Pedicle Subtraction Osteotomy Plays a Crucial Role in the Remodeling of Harmonious Sagittal Curve for Severe Thoracolumbar Kyphotic Deformity Caused by Ankylosing Spondylitis. Neurosurgery 2023; 93:128-136. [PMID: 36757186 DOI: 10.1227/neu.0000000000002390] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Accepted: 12/06/2022] [Indexed: 02/10/2023] Open
Abstract
BACKGROUND Few studies reported the remodeling of harmonious sagittal curve after 2-level pedicle subtraction osteotomy (PSO) for severe thoracolumbar kyphosis in ankylosing spondylitis (AS). OBJECTIVE To investigate how the orientation of osteotomized vertebrae (OV) affects the remodeling of harmonious sagittal curve in patients with AS undergoing 2-level PSO. METHODS Twenty-six patients treated with 2-level PSO were reviewed. Plumb lines of thoracic apex and lumbar apex, the superior/inferior endplate angle of OV, and OV tilt were measured. Patients with AS were grouped based on the postoperative lumbar lordotic apex (LLA, L3 or L4 vs L5 or others). RESULTS The level of thoracic kyphotic apex was positively correlated with that of superior OV postoperatively. Larger sacral slope, L1-L3 lordotic angle, and plumb lines of lumbar apex could be obtained in patients with LLA at L3 or L4, accompanied with larger superior endplate angle of OV and OV tilt of inferior OV ( P < .05). Besides, larger lumbar lordotic angle (LL) was observed in these patients (marginally significant, P = .057). For patients with relocated LLA at L5 or others, lower pelvic incidence was observed, accompanied with significant loss of correction ( P < .05) and worse Visual Analog Scale scores (marginally significant, P = .054) during follow-up. CONCLUSION Ventrally leaning inferior OV combined with dorsally leaning superior OV contributed to the most harmonious sagittal curve defined as thoracic kyphotic apex at T8 or above and LLA at L3 or L4. Sagittal curve with LLA at L5 could be acceptable in patients with more severe kyphosis, especially those with low pelvic incidence.
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Affiliation(s)
- Yao Li
- Division of Spine Surgery, Department of Orthopedic Surgery, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Nanjing, China
- Medical School of Nanjing University, Nanjing, China
| | - Bang-Ping Qian
- Division of Spine Surgery, Department of Orthopedic Surgery, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Nanjing, China
| | - Yong Qiu
- Division of Spine Surgery, Department of Orthopedic Surgery, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Nanjing, China
| | - Yang Yu
- Division of Spine Surgery, Department of Orthopedic Surgery, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Nanjing, China
| | - Bin Wang
- Division of Spine Surgery, Department of Orthopedic Surgery, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Nanjing, China
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Raganato R, Pizones J, Yilgor C, Moreno-Manzanaro L, Vila-Casademunt A, Sánchez-Márquez JM, Fernández-Baíllo N, Sánchez Pérez-Grueso FJ, Kleinstück F, Alanay A, Obeid I, Pellisé F. Sagittal realignment: surgical restoration of the global alignment and proportion score parameters: a subgroup analysis. What are the consequences of failing to realign? Eur Spine J 2023:10.1007/s00586-023-07649-w. [PMID: 37000217 DOI: 10.1007/s00586-023-07649-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 12/28/2022] [Revised: 02/18/2023] [Accepted: 03/09/2023] [Indexed: 04/01/2023]
Abstract
INTRODUCTION The Global Alignment and Proportion (GAP) score incorporates three domains directly modified with surgery (relative pelvic version-RPV, relative lumbar lordosis-RLL, lumbar distribution index-LDI) and one indirectly restored (relative spinopelvic alignment-RSA). We analyzed our surgical realignment performance and the consequences of domain-specific realignment failure on mechanical complications and PROMs. MATERIALS AND METHODS From an adult spinal deformity prospective multicenter database, we selected patients: fused to pelvis, upper instrumented vertebra at or above L1, and 2 years of follow-up. Descriptive, univariate and multivariate analyses were employed. RESULTS The sample included 333 patients. RLL-6w showed the highest success rate (58.3% aligned), but 16.5% of patients were classified in the "Severe hypolordosis" and "Hyperlordosis" subgroups. RPV-6w was the most challenging to realign, with 51.6% moderate or severe retroversion. Regarding RSA-6w, 21.9% had severe positive malalignment. Correct alignment of RPV-6w (p = 0.025) and RSA-6w (p = 0.002) proved to be protective factors against the development of mechanical complications. Severe pelvic retroversion (p = 0.026) and severe positive malalignment (p = 0.007) were risk factors for mechanical complications. RSA-6w "Severe positive malalignment" was associated with less improvement in PROMs: ∆ODI (8.83 vs 17.2; p = 0.011), ∆SRS-22 total (0.54 vs 0.87; p = 0.007), and ∆SF-36PCS (3.47 vs 7.76; p = 0.04); MCID for ODI (37.0 vs 55.5%; p = 0.023), and SRS-22 (40.8 vs 60.1%; p = 0.015); and PASS for ODI (17.6 vs 31.7%; p = 0.047). CONCLUSIONS RPV was the most underperformed modifiable parameter. Severe pelvic retroversion and severe positive malalignment influenced the occurrence of mechanical complications. Severe positive malalignment affected PROMs improvement.
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Affiliation(s)
- Riccardo Raganato
- Spine Unit, Department of Orthopedic Surgery, Hospital La Paz, Paseo de La Castellana 261, 28046, Madrid, Spain
| | - Javier Pizones
- Spine Unit, Department of Orthopedic Surgery, Hospital La Paz, Paseo de La Castellana 261, 28046, Madrid, Spain.
| | - Caglar Yilgor
- Department of Orthopedics and Traumatology, Acibadem Mehmet Ali Aydinlar University, Istanbul, Turkey
| | - Lucía Moreno-Manzanaro
- Spine Unit, Department of Orthopedic Surgery, Hospital La Paz, Paseo de La Castellana 261, 28046, Madrid, Spain
| | | | - José Miguel Sánchez-Márquez
- Spine Unit, Department of Orthopedic Surgery, Hospital La Paz, Paseo de La Castellana 261, 28046, Madrid, Spain
| | - Nicomedes Fernández-Baíllo
- Spine Unit, Department of Orthopedic Surgery, Hospital La Paz, Paseo de La Castellana 261, 28046, Madrid, Spain
| | | | - Frank Kleinstück
- Department of Orthopedics, Schulthess Klinik, Zurich, Switzerland
| | - Ahmet Alanay
- Department of Orthopedics and Traumatology, Acibadem Mehmet Ali Aydinlar University, Istanbul, Turkey
| | - Ibrahim Obeid
- Spine Surgery Unit, Pellegrin University Hospital, Bordeaux, France
| | - Ferran Pellisé
- Spine Surgery Unit, Hospital Universitario Vall d'Hebron, Barcelona, Spain
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Teli M, Umana GE, Palmisciano P, Lee MK, Clark SR, Soda C. Anterior To Psoas lumbar and lumbosacral combined with posterior reconstruction in Adult Spinal Deformity: A bicentric European study. Brain Spine 2023; 3:101718. [PMID: 37383431 PMCID: PMC10293315 DOI: 10.1016/j.bas.2023.101718] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Revised: 12/29/2022] [Accepted: 01/30/2023] [Indexed: 06/30/2023]
Abstract
Introduction Lateral lumbar fusion via the trans-psoas approach is popular in adult deformity reconstruction. To overcome its limitations (neurological damage to the plexus and lack of applicability to the lumbosacral junction), a modified anterior-to-psoas (ATP) approach has been described and used. Research question To investigate the results of ATP lumbar and lumbosacral fusion, in a cohort of adult patients treated with combined anteroposterior approaches for adult spinal deformity (ASD). Materials and methods ASD patients surgically treated at two tertiary spinal centres were followed up. Forty patients were treated with combined ATP and posterior surgery: 11 with open lumbar lateral interbody-fusions (lumbotomy LLIF) and 29 with lesser invasive oblique lateral interbody-fusions (OLIF). Preoperative demographics, aetiology, clinical characteristics, and spinopelvic parameters were comparable between the two cohorts. Results At a minimum 2-year follow-up, both cohorts showed significant improvements in patient reported outcome measures (PROMs), i.e. Visual Analogue Scale and Core Outcome Measures Index, as well as radiological parameters, with no significant differences based on the type of surgical approach. No significant differences were found in major (P = 0.457) and minor (P = 0.071) complications between the two cohorts. Discusson and conclusion Anterolateral lumbar interbody fusions, whether performed via a direct or oblique approach, proved to be safe and effective adjuvants to posterior surgery in patients with ASD. No significant complication differences were noted between techniques. In addition, the anterior-to-psoas approaches limited the risks of post-operative pseudoarthrosis by providing solid anterior support to lumbar and lumbosacral segments, demonstrating a positive impact on PROMS.
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Affiliation(s)
- Marco Teli
- Department of Neurosurgery, The Walton Centre NHS Trust, Liverpool, UK
- Department of Spinal Surgery, Rizzola Academy, Venice, Italy
| | | | | | - Maggie K. Lee
- Department of Neurosurgery, The Walton Centre NHS Trust, Liverpool, UK
| | - Simon R. Clark
- Department of Neurosurgery, The Walton Centre NHS Trust, Liverpool, UK
| | - Christian Soda
- Department of Neurosurgery, Hospital Borgo Roma, Verona, Italy
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Lopez Poncelas M, La Barbera L, Rawlinson JJ, Polly DW, Aubin CE. Influence of spinal lordosis correction location on proximal junctional failure: a biomechanical study. Spine Deform 2023; 11:49-58. [PMID: 36083462 DOI: 10.1007/s43390-022-00571-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Accepted: 08/13/2022] [Indexed: 10/14/2022]
Abstract
STUDY DESIGN Assessment of sagittal lordosis distribution on mechanical proximal junctional failure-related risks through computer-based biomechanical models. OBJECTIVE To biomechanically assess how lordosis distribution influences radiographical and biomechanical indices related to Proximal Junctional Failure (PJF). The "optimal" patient-specific targets to restore the sagittal balance in posterior spinal fusion are still not known. Among these, the effect of the lumbar lordosis correction strategy on complications such as PJF remain uncertain. METHODS In this computational biomechanical study, five adult spinal deformity patients who underwent posterior spinal fixation were retrospectively reviewed. Their surgery, first erect posture and flexion movement were simulated with a patient-specific multibody model. Three pedicle subtraction osteotomy (PSO) levels (L3, L4, and L5) were simulated, with consistent global lordosis for a given patient and pelvic tilt adjusted accordingly to the actual surgery. Computed loads on the anterior spine and instrumentation were analyzed and compared using Kruskal-Wallis statistical tests and Spearman correlations. RESULTS In these models, no significant correlations were found between the lordosis distribution index (LDI), PSO level and biomechanical PJF-related indices. However, increasing the sagittal vertical axis (SVA) and thoracolumbar junction angle (TLJ) and decreasing the sacral slope (SS) increased the bending moment sustained by the rods at the proximal instrumented level (r = 0.52, 0.57, - 0.56, respectively, p < 0.05). There was a negative correlation between SS and the bending moment held by the adjacent proximal segment (r = - 0.71, p < 0.05). CONCLUSION Based on these biomechanical simulations, there was no correlation between the lordosis distribution and PJF-associated biomechanical factors. However, increasing SS and flattening the TLJ, as postural adjustment strategies required by a more distal PSO, did decrease such PJF-related factors. Sagittal restoration and PJF risks remain multifactorial, and the use of patient-specific biomechanical models may help to better understand the complex interrelated mechanisms.
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Affiliation(s)
- Maeva Lopez Poncelas
- Department of Mechanical Engineering, Polytechnique Montréal, Downtown Station, P.O. Box 6079, Montreal, QC, H3C 3A7, Canada.,Research Center, Sainte-Justine University Hospital Center, 3175, Cote Sainte-Catherine Road, Montreal, QC, H3T 1C5, Canada
| | - Luigi La Barbera
- Department of Mechanical Engineering, Polytechnique Montréal, Downtown Station, P.O. Box 6079, Montreal, QC, H3C 3A7, Canada.,Research Center, Sainte-Justine University Hospital Center, 3175, Cote Sainte-Catherine Road, Montreal, QC, H3T 1C5, Canada.,Laboratory of Biological Structure Mechanics, Department of Chemistry, Materials and Chemical Engineering "Giulio Natta", Politecnico di Milano, Piazza Leonardo da Vinci, 32 20133, Milan, MI, Italy
| | - Jeremy J Rawlinson
- Department of Mechanical Engineering, Polytechnique Montréal, Downtown Station, P.O. Box 6079, Montreal, QC, H3C 3A7, Canada.,Spine Applied Research, Cranial and Spinal Technologies Medtronic, 18400 Pyramid Place, Memphis, TN, 38132, USA
| | - David W Polly
- Department of Orthopaedic Surgery, University of Minnesota, 2512 South 7th Street, Suite R200, Minneapolis, MN, 55455, USA
| | - Carl-Eric Aubin
- Department of Mechanical Engineering, Polytechnique Montréal, Downtown Station, P.O. Box 6079, Montreal, QC, H3C 3A7, Canada. .,Research Center, Sainte-Justine University Hospital Center, 3175, Cote Sainte-Catherine Road, Montreal, QC, H3T 1C5, Canada.
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Panico M, Bertoli M, Villa TMT, Galbusera F, Messori M, La Maida GA, Misaggi B, Gallazzi E. Does the anterior column realignment technique influences the stresses on posterior instrumentation in sagittal imbalance correction? A biomechanical, finite-element analysis of L5-S1 ALIF and L3-4 lateral ACR. Spine Deform 2023; 11:41-47. [PMID: 35999490 DOI: 10.1007/s43390-022-00567-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/23/2022] [Accepted: 07/30/2022] [Indexed: 10/15/2022]
Abstract
STUDY DESIGN Biomechanical finite-element study. OBJECTIVE To directly compare the biomechanical effects of two different techniques for sagittal plane correction of adult spine deformity based on the anterior longitudinal ligament (ALL) resection and use of hyperlordotic cages, namely, the anterior column realignment (ACR) in L3-4, and ALIF in L5-S1 in terms of primary stability and rod stresses using finite-element models. METHODS A finite-element model of the thoracolumbar spine was used to perform the analysis. Starting from this "intact" model, three further models were constructed through the insertion of spinal instrumentation, i.e., pedicle screws, rods and cages: 1) posterior instrumentation between T9 and S1 (referred to as "T9-S1"); 2) posterior instrumentation T9-S1 + Hyperlordotic (26°) ALIF cage in L5-S1 ("ALIF"); 3) posterior instrumentation T9-S1 + Hyperlordotic (30°) ACR cage in L3-4 ("ACR"). These models were studied by simulations applying, alternately, a pure moment of 7.5 Nm between the three planes of motion (flexion, extension, lateral bending, and bilateral axial rotation), uniformly distributed over the upper surface of the T9 thoracic vertebra. A total of 24 simulations were performed (6 per models). RESULTS All models presented a significant reduced ROM when compared to the intact model; the ROM reduction was higher both at L3-4 in the ACR model and at L5-S1 in the ALIF model. At L3-4, the ACR model had, in all cases, the lowest maximum values of Von Mises stresses on the rods, especially in flexion-extension. At L4-5, the ALIF model had the lowest stresses during flexion-extension and axial rotation, while the ACR model had the lowest stresses during lateral bending. At L5-S1, the ALIF model had, in all cases, the lowest stresses on the rods. CONCLUSIONS This finite-element study showed how both ACR at L3-4 and ALIF-ACR at L5-S1 are effective in restoring lumbar lordosis (LL), stabilizing the spine and reducing stress on posterior rods at the index level when compared to a simple fixation model. Interestingly, ALIF-ACR reduces rod stress even at L4-5 in flexion-extension and axial rotation, possibly due to a better distribution of LL, especially on the lower arch, while ACR reduces the stress at L4-5 in lateral bending, possibly thanks to the larger footprint of the cage that increases the area of contact with the lateral side of the endplates.
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Affiliation(s)
- Matteo Panico
- IRCCS Istituto Ortopedico Galeazzi, Milano, Italy.,Department of Chemistry, Materials and Chemical Engineering "Giulio Natta", Politecnico Di Milano, Milano, Italy
| | - Marco Bertoli
- Department of Chemistry, Materials and Chemical Engineering "Giulio Natta", Politecnico Di Milano, Milano, Italy
| | - Tomaso Maria Tobia Villa
- IRCCS Istituto Ortopedico Galeazzi, Milano, Italy.,Department of Chemistry, Materials and Chemical Engineering "Giulio Natta", Politecnico Di Milano, Milano, Italy
| | | | | | | | - Bernardo Misaggi
- U.O.C. Patologia Vertebrale E Scoliosi, ASST Gaetano Pini-CTO, Milano, Italy
| | - Enrico Gallazzi
- U.O.C. Patologia Vertebrale E Scoliosi, ASST Gaetano Pini-CTO, Milano, Italy.
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Shekouhi N, Vosoughi AS, Goel VK, Theologis AA. Does number of rods matter? 4-, 5-, and 6-rods across a lumbar pedicle subtraction osteotomy: a finite element analysis. Spine Deform 2022; 11:535-543. [PMID: 36484928 PMCID: PMC10147790 DOI: 10.1007/s43390-022-00627-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/07/2022] [Accepted: 11/26/2022] [Indexed: 12/13/2022]
Abstract
PURPOSE To assess biomechanics of a lumbar PSO stabilized with different multi-rod constructs (4-, 5-, 6-rods) using satellite and accessory rods. METHODS A validated spinopelvic finite element model with a L3 PSO was used to evaluate the following constructs: 2 primary rods T10-pelvis ("Control"), two satellite rods (4-rod), two satellite rods + one accessory rod (5-rod), or two satellite rods + two accessory rods (6-rod). Data recorded included: ROM T10-S1 and L2-L4, von Mises stresses on primary, satellite, and accessory rods, factor of safety yield stress, and force across the PSO surfaces. Percent differences relative to Control were calculated. RESULTS Compared to Control, 4-rods increased PSO flexion and extension. Lower PSO ROMs were observed for 5- and 6-rods compared to 4-rods. However, 4-rod (348.6 N) and 5-rod (343.2 N) showed higher PSO forces than 2-rods (336 N) and 6-rods had lower PSO forces (324.2 N). 5- and 6-rods led to the lowest rod von Mises stresses across the PSO. 6-rod had the maximum factor of safety on the primary rods. CONCLUSIONS In this finite element analysis, 4-rods reduced stresses on primary rods across a lumbar PSO. Although increased rigidity afforded by 5- and 6-rods decreased rod stresses, it resulted in less load transfer to the anterior vertebral column (particularly for 6-rod), which may not be favorable for the healing of the anterior column. A balance between the construct's rigidity and anterior load sharing is essential.
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Affiliation(s)
- Niloufar Shekouhi
- Engineering Center for Orthopedic Research Excellence (E-CORE), Departments of Bioengineering and Orthopaedic Surgery, University of Toledo, Toledo, OH, USA
| | - Ardalan S Vosoughi
- Engineering Center for Orthopedic Research Excellence (E-CORE), Departments of Bioengineering and Orthopaedic Surgery, University of Toledo, Toledo, OH, USA
| | - Vijay K Goel
- Engineering Center for Orthopedic Research Excellence (E-CORE), Departments of Bioengineering and Orthopaedic Surgery, University of Toledo, Toledo, OH, USA
| | - Alekos A Theologis
- Department of Orthopaedic Surgery, University of California-San Francisco (UCSF), 500 Parnassus Ave, MUW 3Rd Floor, San Francisco, CA, 94143, USA.
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12
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Platz U, Halm H, Thomsen B, Pecsi F, Köszegvary M, Bürger N, Berlin C, Quante M. Anterior Lumbar Interbody Fusion (ALIF) or Transforaminal Lumbar Interbody Fusion (TLIF) for Fusion Surgery in L5/S1 - What Is the Best Way to Restore a physiological Alignment? Z Orthop Unfall 2022; 160:646-656. [PMID: 34496423 DOI: 10.1055/a-1560-3106] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
STUDY DESIGN A retrospective single center cohort study with prospective collected data from an institutional spine registry. OBJECTIVES To determine whether restoration of lordosis L5/S1 is possible with both anterior lumbar interbody fusion (ALIF) and transforaminal lumbar interbody fusion (TLIF) and to find out which technique is superior to recreate lordosis in L5/S1. METHODS Seventy-seven patients with ALIF and seventy-nine with TLIF L5/S1 were included. Operation time, estimated blood loss), and complications were evaluated. Segmental lordosis L5/S1 and L4/5, overall lordosis, and proximal lordosis (L1 to L4) were measured in X-rays before and after surgery. Oswesery disability index and EQ-5D were assessed before surgery, and 3 and 12 months after surgery. RESULTS Mean operation time was 176.9 minutes for ALIF and 195.7 minutes for TLIF (p = 0.048). Estimated blood loss was 249.2 cc for ALIF and 362.9 cc for TLIF (p = 0.005). In terms of complications, only a difference in dural tears were found (TLIF 6, ALIF none; p = 0.014). Lordosis L5/S1 increased in the ALIF group (15.8 to 24.6°; p < 0.001), whereas no difference was noted in the TLIF group (18.4 to 19.4°; p = 0.360). Clinical results showed significant improvement in the Oswesery disability index (ALIF: 43 to 21.9, TLIF: 45.2 to 23.0) and EQ-5D (ALIF: 0.494 to 0.732, TLIF: 0.393 to 0.764) after 12 months in both groups, without differences between the groups. CONCLUSION ALIF and TLIF are comparable methods for performing fusion at L5/S1, with good clinical outcomes and comparable rates of complications. However, there is only a limited potential for recreating lordosis at L5/S1 with a TLIF.
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Affiliation(s)
- Uwe Platz
- UniversitätsCentrum für Orthopädie, Unfall- und Plastische Chirurgie, Universitätsklinikum Carl Gustav Carus, Dresden, Germany
| | - Henry Halm
- Wirbelsäulenchirurgie mit Skoliosezentrum, Schön Klinik Neustadt, Neustadt in Holstein, Germany
| | - Björn Thomsen
- Wirbelsäulenchirurgie mit Skoliosezentrum, Schön Klinik Neustadt, Neustadt in Holstein, Germany
| | - Ferenc Pecsi
- Klinik für Wirbelsäulenchirurgie, Schön Klinik Neustadt, Neustadt in Holstein, Germany
| | - Mark Köszegvary
- Wirbelsäulenchirurgie mit Skoliosezentrum, Schön Klinik Neustadt, Neustadt in Holstein, Germany
| | - Nina Bürger
- Wirbelsäulenchirurgie mit Skoliosezentrum, Schön Klinik Neustadt, Neustadt in Holstein, Germany
| | - Clara Berlin
- Wirbelsäulenchirurgie mit Skoliosezentrum, Schön Klinik Neustadt, Neustadt in Holstein, Germany
| | - Markus Quante
- Wirbelsäulenchirurgie mit Skoliosezentrum, Schön Klinik Neustadt, Neustadt in Holstein, Germany
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Wang J, Zhang Q, Liu F, Yuan H, Zhang Y, Wang X, Li J. Predicting the ideal apex of lumbar lordosis based on individual pelvic incidence and inflection point in asymptomatic adults. Front Surg 2022; 9:912357. [PMID: 36248369 PMCID: PMC9556969 DOI: 10.3389/fsurg.2022.912357] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Accepted: 09/06/2022] [Indexed: 11/26/2022] Open
Abstract
Objective The main aim of this study was to comprehensively explore the relationship among pelvic incidence (PI), inflection point (IP), and apex of lumbar lordosis (LLA), and establish a predictive formula for LLA based on individual PI and IP in asymptomatic Chinese adults. Methods A total of 385 asymptomatic adults with average age 38.3 ± 11.9 years (range 20–73 years) were recruited between November 2020 and October 2021. Full-spine, standing x-rays were then obtained from each participant. Next, the following sagittal parameters were measured: PI, IP, LLA, the horizontal offset between the plumb line of the lumbar apex and that of the posterosuperior corner of S1 (LASO), the upper lumbar lordosis (ULL) and lower lumbar lordosis (LLL), lumbar lordosis (LL), and thoracic kyphosis (TK). Moreover, the association among PI, IP, and the other sagittal parameters was evaluated, followed by linear regression analyses. A P-value of <0.05 was considered statistically significant. Results PI showed statistically significant correlations with LLA (rs = −0.629; P < 0.01), LASO (rs = 0.537; P < 0.01), LLL (rs = 0.788; P < 0.01), and LL (rs = 0.663; P < 0.01). On the other hand, IP also showed statistically significant correlations with LLA (rs = 0.671; P < 0.01), LASO (rs = −0.493; P < 0.01), LLL (rs = −0.402; P < 0.01), and LL (rs = −0.283; P < 0.01). The corresponding predictive formulae were displayed as follows: LLA = −0.03 * PI + 0.23 * IP + 14.45 (R2 = 0.669); LASO = 0.38 * PI−2.09 * IP + 53.62 (R2 = 0.460); and LLL = 0.58 * PI−0.88 * IP + 18.86 (R2 = 0.659). Conclusion The specific lumbar shape should be modulated by pelvic morphology and IP level. In addition, we established predictive formulae for ideal sagittal lumbar profile based on individual PI and IP, with the overarching goal of helping surgeons to better comprehend the regulatory mechanisms of the individual sagittal lumbar alignment, and design a precise and personalized corrective plan.
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Affiliation(s)
| | | | | | | | | | | | - Jing Li
- Correspondence: Xiaobin Wang ; Jing Li
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Yilgor C, Kindan P, Yucekul A, Zulemyan T, Alanay A. Osteotomies for the Treatment of Adult Spinal Deformities: A Critical Analysis Review. JBJS Rev 2022; 10:01874474-202205000-00010. [PMID: 35613311 DOI: 10.2106/jbjs.rvw.21.00226] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
» Spinal osteotomies are powerful deformity correction techniques that may be associated with serious complications. » The anatomical spinal osteotomy classification system proposes 6 grades of resection corresponding to different anatomic bone, disc, facet, and ligament interventions. » Surgeons should be aware of the nuances of 3-column osteotomies with regard to spinal level selection, construct composition, and posterior column reconstruction and closure techniques. » There is a global tendency toward avoiding 3-column osteotomies as much as possible because of the growing evidence regarding the effectiveness of posterior column osteotomies and halo-gravity traction.
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Affiliation(s)
- Caglar Yilgor
- Department of Orthopedics and Traumatology, Acibadem Mehmet Ali Aydinlar University School of Medicine, Istanbul, Turkey
| | - Peri Kindan
- Acibadem Mehmet Ali Aydinlar University School of Medicine, Istanbul, Turkey
| | - Altug Yucekul
- Department of Orthopedics and Traumatology, Acibadem Mehmet Ali Aydinlar University School of Medicine, Istanbul, Turkey
| | - Tais Zulemyan
- Comprehensive Spine Center, Acibadem University Maslak Hospital, Istanbul, Turkey
| | - Ahmet Alanay
- Department of Orthopedics and Traumatology, Acibadem Mehmet Ali Aydinlar University School of Medicine, Istanbul, Turkey
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Wang J, Zhang Q, Liu F, Yuan H, Zhang Y, Wang X, Li J. Restoring Theoretically Optimal Lumbar Lordosis Deduced from Pelvic Incidence and Thoracic Kyphosis has Advantages to Decrease the Risk of Postoperative Mechanical Complications in Adult Spinal Deformity. Front Surg 2022; 9:860564. [PMID: 35478724 PMCID: PMC9035901 DOI: 10.3389/fsurg.2022.860564] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2022] [Accepted: 03/25/2022] [Indexed: 11/13/2022] Open
Abstract
ObjectiveTo establish a regression formula for LL based on individual PI and TK in asymptomatic population aged over 50 years and evaluate its predictive power for the occurrence of postoperative mechanical complications in patients with adult spinal deformity (ASD).MethodsA total of 178 asymptomatic adults were recruited for the study. The association between LL and PI, LL and TK, was investigated to establish a predictive formula for ideal LL based on PI and TK. Additionally, 93 ASD patients undergoing posterior correction surgery were retrospectively analyzed. The absolute value of the gap between postoperative actual LL and theoretical LL was defined as ΔLL. Patients were classified into two groups depending on the presence or absence of mechanical complications. The demographic and radiological data of patients were compared between the two groups.ResultsA significant association was found between LL and PI (r = 0.599, P < 0.001), LL and TK (r = 0.523, P < 0.001). A novel formula was developed as follows: LL = 0.7*PI + 0.4*TK + 1 (R2 = 0.524). In the validation cohort, 29 patients developed mechanical complications. Postoperative ΔLL (12.5 ± 7.6° vs. 7.0 ± 5.4°, P = 0.001) significantly increased the incidence of mechanical complications. The most appropriate threshold of ΔLL for predicting mechanical complications was 9.8°. For patients whose ΔLL were <9.8° and >9.8°, the incidence of mechanical complications was 19.4% and 54.8%, respectively.ConclusionIdeal lumbar lordosis should be matched for PI and TK. The developed prediction formula for LL based on PI and TK in asymptomatic adults may help surgeons to understand the mechanisms of lumbar alignment generation and predict occurrence of mechanical complications after ASD surgery.
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Affiliation(s)
| | | | | | | | | | | | - Jing Li
- Correspondence: Xiaobin Wang Jing Li
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Pizones J, Perez-Grueso FJS, Moreno-Manzanaro L, Escámez F, Yilgor C, Vila-Casademunt A, Fernández-Baíllo N, Sánchez-Márquez JM, Obeid I, Kleinstück F, Alanay A, Pellisé F. Compensatory mechanisms recruited against proximal junctional kyphosis by patients instrumented from the thoracolumbar junction to the iliac. Eur Spine J 2021; 31:112-122. [PMID: 34750669 DOI: 10.1007/s00586-021-07042-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2021] [Revised: 10/12/2021] [Accepted: 10/18/2021] [Indexed: 10/19/2022]
Abstract
PURPOSE The compensatory mechanisms recruited by un-instrumented patients against sagittal imbalance are well documented. However, there is a lack of information regarding instrumented patients. MATERIAL AND METHODS We performed a retrospective analysis of data collected prospectively in a multicenter adult spinal deformity database. We included patients suffering PJK/PJF after (T8-L2) to iliac instrumentation with minimum two-year follow-up. We measured quantitative sagittal spinopelvic and qualitative sagittal distribution parameters in the immediate postoperative period (6w) and at the time of PJK/PJF appearance. We analyzed how these parameters changed comparing these two time points with univariate and multivariate logistic regression analyses. RESULTS A total of 69 patients were included. Two different patterns at PJK/PJF were found: 36 patients activated compensation (defined as an increase in pelvic retroversion (ΔRPV > 5º), and 33 did not (ΔRPV < 5º). The difference in behavior relied mostly on the amount of not surgically restored pelvic rotation at 6w (OR: 0.6; CI95%: 0.4-9.2; P = 0.017). Non-compensators had less rotation reserve (PTx100/PI = 33.9% vs 47.8%;P < 0.001) associated with worse 6w relative pelvic version and lower lumbar arc restoration, worse 6w relative sagittal alignment and GAP-score, compared with compensators (P < 0.001). Compensators' response was based on pelvic retroversion, causing lower lumbar arc decrease, lumbar apex caudal migration, and upper lumbar arc posterior inclination. Despite compensation, a thoracic kyphosis increase in both upper and lower arches gradually evolved into a PJK/PJF. Non-compensators did not react to PJK/PJF, which forced them into kyphosis from the lumbar apex and extending cranially, mainly throughout the upper thoracic arc. CONCLUSIONS In patients fused from the TL junction to the iliac, those having greater postoperative pelvic rotation reserve showed greater capacity to recruit compensatory mechanisms against PJK/PJF.
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Affiliation(s)
- Javier Pizones
- Department of Orthopedic Surgery, Spine Unit, Hospital Universitario La Paz, Paseo de la Castellana 261, 28046, Madrid, Spain.
| | | | - Lucía Moreno-Manzanaro
- Department of Orthopedic Surgery, Spine Unit, Hospital Universitario La Paz, Paseo de la Castellana 261, 28046, Madrid, Spain
| | - Fernando Escámez
- Department of Orthopedic Surgery, Spine Unit, Hospital Universitario La Paz, Paseo de la Castellana 261, 28046, Madrid, Spain
| | - Caglar Yilgor
- Department of Orthopedics and Traumatology, Acibadem Mehmet Ali Aydinlar University, Istanbul, Turkey
| | | | - Nicomedes Fernández-Baíllo
- Department of Orthopedic Surgery, Spine Unit, Hospital Universitario La Paz, Paseo de la Castellana 261, 28046, Madrid, Spain
| | - José Miguel Sánchez-Márquez
- Department of Orthopedic Surgery, Spine Unit, Hospital Universitario La Paz, Paseo de la Castellana 261, 28046, Madrid, Spain
| | - Ibrahim Obeid
- Spine Surgery Unit, Pellegrin University Hospital, Bordeaux, France
| | - Frank Kleinstück
- Department of Orthopedics, Schulthess Klinik, Zurich, Switzerland
| | - Ahmet Alanay
- Department of Orthopedics and Traumatology, Acibadem Mehmet Ali Aydinlar University, Istanbul, Turkey
| | - Ferran Pellisé
- Spine Surgery Unit, Hospital Universitario Vall d'Hebron, Barcelona, Spain
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Faundez AA, Tsoupras A, Le Huec JC. Rationale and techniques for Posterior Opening Wedge Osteotomy (POWO) in proximal junctional failure due to iatrogenic lumbar hyperlordosis. Orthop Traumatol Surg Res 2021; 107:102657. [PMID: 32778438 DOI: 10.1016/j.otsr.2020.04.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/15/2019] [Revised: 04/05/2020] [Accepted: 04/14/2020] [Indexed: 02/03/2023]
Abstract
Proximal junctional kyphosis (PJK) is a compensatory phenomenon in reaction to pathologic lumbar hyperlordosis. Inappropriate spinal curve harmony incurs risk of PJK. Postoperative failure of posterior instrumentation, with kyphosis resistant to revision surgery at the proximal junction, may be caused by excessive iatrogenic lumbar lordosis. The surgical attitude should be to decrease lumbar lordosis by posterior opening wedge osteotomy (POWO). We describe the rationale for POWO and surgical techniques at L3. The technique is illustrated by a case report at 24 months' follow-up. Based on rational analysis of the distribution of lordosis along the lumbar spine and of adaptation of the sitting position, POWO may be indicated to avoid PJK after revision surgery in adult spinal Deformation revision surgery.
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Affiliation(s)
- Antonio A Faundez
- Orthopaedic Surgery Division, Department of Surgery, Geneva University Hospitals, Hôpital La Tour Meyrin, 4, rue Perret-Gentil, 1211 Geneva, Switzerland.
| | - Andreas Tsoupras
- Orthopaedic Surgery Division, Department of Surgery, Geneva University Hospitals, Hôpital La Tour Meyrin, 4, rue Perret-Gentil, 1211 Geneva, Switzerland
| | - Jean-Charles Le Huec
- Polyclinique Bordeaux Nord, Centre Vertebra, 15, rue Boucher, 33000 Bordeaux, France
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Bari TJ, Heegaard M, Bech-Azeddine R, Dahl B, Gehrchen M. Lordosis Distribution Index in Short-Segment Lumbar Spine Fusion - Can Ideal Lordosis Reduce Revision Surgery and Iatrogenic Deformity? Neurospine 2021; 18:543-553. [PMID: 34610685 PMCID: PMC8497240 DOI: 10.14245/ns.2040744.372] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Accepted: 02/02/2021] [Indexed: 11/19/2022] Open
Abstract
OBJECTIVE The demand for spinal fusion is increasing, with concurrent reports of iatrogenic adult spinal deformity (flatback deformity) possibly due to inappropriate lordosis distribution. This distribution is assessed using the lordosis distribution index (LDI) which describes the upper and lower arc lordosis ratio. Maldistributed LDI has been associated to adjacent segment disease following interbody fusion, although correlation to later-stage deformity is yet to be assessed. We therefore aimed to investigate if hypolordotic lordosis maldistribution was associated to radiographic deformity-surrogates or revision surgery following instrumented lumbar fusion. METHODS All patients undergoing fusion surgery ( ≤ 4 vertebra) for degenerative lumbar diseases were retrospectively included at a single center. Patients were categorized according to their postoperative LDI as: "normal" (LDI 50-80), "hypolordotic" (LDI < 50), or "hyperlordotic" (LDI > 80). RESULTS We included 149 patients who were followed for 21 ± 14 months. Most attained a normally distributed lordosis (62%). The hypolordotic group had increased postoperative pelvic tilt (PT) (p < 0.001), pelvic incidence minus lumbar lordosis (PI-LL) mismatch (p < 0.001) and decreased global lordosis (p = 0.007) compared to the normal group. Survival analyses revealed a significant difference in revision surgery (p = 0.03), and subsequent multivariable logistic regression showed increased odds of 1-year revision in the hypolordotic group (p = 0.04). There was also a negative, linear correlation between preoperative pelvic incidence (PI) and postoperative LDI (p < 0.001). CONCLUSION In patients undergoing instrumented lumbar fusion surgery, hypolordotic lordosis maldistribution (LDI < 50) was associated to increased risk of revision surgery, increased postoperative PT and PI-LL mismatch. Lordosis distribution should be considered prior to spinal fusion, especially in high PI patients.
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Affiliation(s)
- Tanvir Johanning Bari
- Spine Unit, Department of Orthopedic Surgery, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark.,Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Martin Heegaard
- Spine Unit, Department of Orthopedic Surgery, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark.,Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Rachid Bech-Azeddine
- Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark.,Copenhagen Spine Research Unit (CSRU), Rigshospitalet, Glostrup, Denmark
| | - Benny Dahl
- Department of Orthopedics and Scoliosis Surgery, Texas Children's Hospital & Baylor College of Medicine, Houston, TX, USA
| | - Martin Gehrchen
- Spine Unit, Department of Orthopedic Surgery, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark.,Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
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Chou D. Commentary on "Modified Global Alignment and Proportion Scoring With Body Mass Index and Bone Mineral Density Analysis in Global Alignment and Proportion Score of Each 3 Categories for Predicting Mechanical Complications After Adult Spinal Deformity Surgery". Neurospine 2021; 18:492-494. [PMID: 34610680 PMCID: PMC8497246 DOI: 10.14245/ns.2142932.466] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Affiliation(s)
- Dean Chou
- Department of Neurosurgery, University of California San Francisco, San Francisco, CA, USA
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Bourghli A, Boissiere L, Chevillotte T, Huneidi M, Silvestre C, Abelin-Genevois K, Grobost P, Pizones J, Roussouly P, Obeid I. Radiographic outcomes and complications after L4 or L5 pedicle subtraction osteotomy for fixed sagittal malalignment in 102 adult spinal deformity patients with a minimum 2-year follow-up. Eur Spine J 2021. [PMID: 34586505 DOI: 10.1007/s00586-021-07008-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2021] [Revised: 08/13/2021] [Accepted: 09/22/2021] [Indexed: 10/20/2022]
Abstract
PURPOSE The objective of this retrospective study was to provide the radiographic outcomes and complications for pedicle subtraction osteotomy (PSO) performed at the low lumbar spine, i.e., L4 or L5 for ASD patients with fixed sagittal malalignment. METHODS ASD patients who underwent L4 or L5 PSO with a minimum 2-year follow-up were included. Preoperative and postoperative radiographs, and complications were collected. Radiographic analysis included lumbar lordosis (LL), pelvic incidence (PI), pelvic tilt (PT), thoracic kyphosis (TK), sagittal vertical axis (SVA), spinal lordosis (SL) ratio and global tilt (GT) on standing long-cassette radiographs. RESULTS A total of 102 patients from 2 spinal centers were analyzed. 66 patients underwent PSO at L4 and 36 patients at L5. From preoperatively to the final follow-up, significant improvements occurred in LL (from - 31° to - 52°), SVA (from 13 to 5 cm), and GT (from 44° to 27°) (all, p < 0.05). 12 patients had transient neurological deficits, and 8 patients had persistent neurological deficit. 23 patients underwent revision for PJK (2), pseudarthrosis (10), neurological deficit (2), epidural hematoma (1), or deep surgical site infection (8). No PJK was observed in any of the patients with L5 PSO. CONCLUSIONS PSO at the level of L4 or L5 remains a challenging technique but with an acceptable rate of complications and revisions. It enables correction of fixed sagittal malalignment in ASD patients with a globally satisfactory outcome. In comparison with L4 PSO, L5 PSO patients did not show PJK as a mechanical complication. Distal lumbar PSO at the level of L5 may represent one of the factors that may help preventing the proximal junctional kyphosis complication.
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Pesenti S, Prost S, McCausland AM, Farah K, Tropiano P, Fuentes S, Blondel B. Optimal Correction of Adult Spinal Deformities Requires Restoration of Distal Lumbar Lordosis. Adv Orthop 2021; 2021:5572181. [PMID: 34040810 DOI: 10.1155/2021/5572181] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Revised: 04/20/2021] [Accepted: 05/01/2021] [Indexed: 11/18/2022] Open
Abstract
PURPOSE The aim of this study is to analyze results according to postoperative pelvic incidence-lumbar lordosis (PI-LL) mismatch in the management of adult spine deformity (ASD) patients. Recently, it has been reported that in addition to lumbar lordosis amount, lordosis repartition between its proximal and distal parts was crucial. METHODS We enrolled 77 consecutive ASD patients who underwent posterior spinal fusion and deformity correction between 2015 and 2018. On preoperative and 1-year follow-up radiographs, we analyzed different parameters such as L1-S1 lumbar lordosis, L1-L4 proximal lordosis (PLL), L4-S1 distal lordosis (DLL), pelvic tilt (PT), sagittal vertical axis (SVA), and PI-LL mismatch. Comparisons were performed according to postoperative PI-LL mismatch (defined as "aligned" when PI-LL was <10°). The relationship between lordosis distribution and postoperative alignment status was investigated. RESULTS On the whole series, average lumbar lordosis, SVA, and PI-LL improved (28.2° vs.43.5°, 82 vs. 51 mm, and 26°vs. 14°, all p < 0.001, respectively). On the other hand, PT remained unchanged (30° vs. 28°, p > 0.05). 35 patients were classified as "aligned" and 42 as "not aligned." Patients from the "aligned" group had a significantly lower PI than patients from the "not aligned" group (52° vs. 61°, p=0.009). Postoperative PLL was not different between groups (18° vs. 16° p > 0.05), whereas DLL was significantly higher in the "aligned" group (31° vs. 22°, p=0.003). PI-LL was significantly correlated to DLL (rho = 0.407, p < 0.001) but not with PLL (rho = 0.110, p=0.342). CONCLUSIONS Our results revealed that in ASD patients, postoperative malalignment was associated with a lack of DLL restoration. "Not aligned" patients had also a significantly higher pelvic incidence. Specific attention must be paid to restore optimal distal lumbar lordosis in order to set the amount and the distribution of optimal postoperative lumbar lordosis.
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Iwai C, Pizones J, Boissière L, Jakinapally S, Yilgor Ç, Larrieu D, Pellise F, Vital JM, Bourghli A, Obeid I. Static and dynamic sagittal lumbar apex: a new concept for the assessment of lumbar lordosis distribution in spinal deformity. Eur Spine J 2021; 30:1155-1163. [PMID: 33606102 DOI: 10.1007/s00586-021-06767-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Revised: 12/20/2020] [Accepted: 02/07/2021] [Indexed: 10/22/2022]
Abstract
PURPOSE Sagittal lumbar apex has been demonstrated to be a key parameter in sagittal plane morphology. Our aim was to understand its behavior with postural changes, analyzing two different concepts of lumbar apex. MATERIALS AND METHODS Prospective observational study with a cohort of patients presenting sagittal malalignment identified from a monocenter database of adult spinal deformities (ASD). Inclusion criteria were age > 30 years, SVA > 40 mm, and/or PT > 20. All patients had full-spine EOS radiographs in 2 different positions: (P1: natural position) and position 2 (P2: compensated position). Sagittal alignment, spinopelvic values, and two different methods of assessing lordosis apex location were analyzed in both P1 and P2 positions. Changes between P1 and P2 were compared using a paired t test with a significance level at p < 0.05. RESULTS Twenty-five patients were recruited (21 women and 4 men). The mean age was 64.8 years (range 21-79). The patient's main compensation was based on an increase in the femoral shaft angle, and pelvic retroversion, with a subsequent decrease in sacral slope, and therefore of the lower lumbar arc. When the lumbar apex was calculated as the most anterior point touching the vertical line in a lateral radiograph, postural compensation changes modified its location usually shifting it to a more caudal position. When the lumbar apex was assessed as the most distant point of the global lumbar lordosis, its position remained stable regardless of compensation. CONCLUSIONS Postural changes can modify the location of the lumbar apex when understanding its location as the cornerstone of sagittal plane harmonic distribution. This concept can be useful as an additional sign to assess compensation. However, if the lumbar apex was calculated as the angular point of the global lordosis, its position remained stable regardless of postural changes. This concept can help to mold lumbar lordosis in ASD surgery. LEVEL OF EVIDENCE IV Diagnostic: individual cross-sectional studies with consistently applied reference standard and blinding.
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Affiliation(s)
- Chizuo Iwai
- Spine Unit 1, Bordeaux University Hospital, Place Amelie Raba-Leon, 33076, Bordeaux, France.,Department of Orthopaedic Surgery, Gifu University Graduate School of Medicine, Gifu, Japan
| | - Javier Pizones
- Spine Surgery Unit, Hospital Universitario La Paz, Madrid, Spain
| | - Louis Boissière
- Spine Unit 1, Bordeaux University Hospital, Place Amelie Raba-Leon, 33076, Bordeaux, France
| | - Sreenath Jakinapally
- Spine Unit 1, Bordeaux University Hospital, Place Amelie Raba-Leon, 33076, Bordeaux, France
| | - Çaglar Yilgor
- Spine Surgery Unit, Acibadem Maslak Hospital, Istanbul, Turkey
| | - Daniel Larrieu
- Spine Unit 1, Bordeaux University Hospital, Place Amelie Raba-Leon, 33076, Bordeaux, France
| | - Ferran Pellise
- Spine Surgery Unit, Hospital Universitario Val Hebron, Barcelona, Spain
| | - Jean-Marc Vital
- Spine Unit 1, Bordeaux University Hospital, Place Amelie Raba-Leon, 33076, Bordeaux, France
| | - Anouar Bourghli
- Orthopedic and Spinal Surgery Department, Kingdom Hospital, Riyadh, Saudi Arabia
| | - Ibrahim Obeid
- Spine Unit 1, Bordeaux University Hospital, Place Amelie Raba-Leon, 33076, Bordeaux, France.
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Abstract
Pelvic motion acting as a hinge between the spine and hips is essential to maintain proper balance during bipedalism. Pelvic rotation is recruited as a compensation mechanism when spinal malalignment occurs.This pelvic rotation can affect functional acetabular orientation, and consequently functional cup positioning if a total hip arthroplasty (THA) is needed. Pelvic retroversion, frequently associated with degenerative spinal changes, implies an increase of acetabular version.Patients with flexible lumbar spines (spine users) protect the hip joint. Patients with stiff, degenerated or fused lumbar spines (hip users) demand higher hip mobility, placing the THA at risk.Pelvises in retroversion place the THA at risk for anterior dislocation when standing. In contrast, pelvises in anteversion or with low pelvic incidence (PI) can place THA at risk for posterior dislocation when sitting.Try to set the cup in an anatomic position. However, bear in mind that low PI pelvises may need more acetabular ante-inclination, and high PI pelvises more acetabular retroversion.If surgery is needed, start first by addressing the hip, except in patients with compensation (high pelvic retroversion), who may need spine surgery first to place the pelvis, and consequently the acetabulum, in a proper position. Cite this article: EFORT Open Rev 2020;5:522-533. DOI: 10.1302/2058-5241.5.200032.
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Affiliation(s)
- Javier Pizones
- Spine Unit, Department of Orthopaedic Surgery, Hospital Universitario La Paz, Madrid, Spain
| | - Eduardo García-Rey
- Hip Unit, Department of Orthopaedic Surgery, Hospital Universitario La Paz, Madrid, Spain
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