Defining threshold for sagittal correction in lumbar fractures.

PURPOSE: Surgical indications for thoraco-lumbar fractures are driven both by neurological status, fractures instability and kyphotic deformity. Regarding kyphotic deformity, an angulation superior to 20° is considered by many surgeons as a surgical indication to reduce the disability induced by post-traumatic kyphosis. However, there is a lack of data reporting the ideal or theoretical lordosis that one must have in a particular lumbar segment on CT-scan. The main goal of this study was to determine the mean value for segmental lumbar lordosis according to pelvic incidence (PI) on a cohort of normal subjects. METHODS: The consecutive CT-scan of 171 normal adult subjects were retrospectively analyzed. The PI and the segmental lordosis (L4S1, L3L5, L2L4, L3L1, L2T12 and T11-L1) were measured on all CT-scan. The mean values were calculated for the global cohort and a sub-group analysis according to IP ranges (< 45°, 45 < IP < 60° and > 60°) was performed. RESULTS: The mean angular values for the whole cohort were IP: 54, 9°; L4S1: - 38, 1°; L3L5: - 30, 6°; L2L4: - 14, 1°; L1L3: - 4, 9°; T12L2: + 1, 9° and T11L1: + 5, 4°. The segmental values vary significatively with PI ranges, as for L3L5: - 26, 8° (PI < 45°); - 30° (45 < PI < 60°) and - 35, 1° (PI > 60°). CONCLUSION: These results provide a referential of theoretical values of segmental lordosis according to PI. This abacus may help spinal surgeon in their decision-making process regarding lumbar fractures, to determine the amount of sagittal correction needed, according to the PI range, to be adapted to the sagittal morphology of the patient. LEVEL OF EVIDENCE: III.

Spinal cord ischemia revealed by a Brown-Sequard syndrome and caused by a calcified thoracic disc extrusion with spontaneous regression: a case report and review of the literature.

BACKGROUND: Thoracic disc herniation is relatively uncommon, accounting for less than 1% of all spinal herniations. Although most often asymptomatic, they may represent a rare cause of spinal cord ischemia. CASE REPORT: We report the case of a healthy 43-year-old North African male who presented with a Brown-Sequard syndrome revealing a spinal cord ischemia caused by a thoracic disc extrusion. The initial MRI revealed a calcified disc extrusion at the level of T5-T6 without significant spinal cord compression or signal abnormality. A pattern consistent with a medullary ischemia only appeared 48 h later. The patient was treated conservatively with Aspirin and Heparin, which were discontinued later because of a negative cardiovascular work-up. The calcified disc extrusion, which was later recognized as the cause of the ischemia, decreased spontaneously over time and the patient recovered within a few months. CONCLUSIONS: Our case highlights the challenge in diagnosing and managing this uncommon condition. We propose a literature review showing the different therapeutic strategies and their corresponding clinical outcomes.

The Whole-Exome Sequencing of a Cohort of 19 Families with Adolescent Idiopathic Scoliosis (AIS): Candidate Pathways.

A significant genetic involvement has been known for decades to exist in adolescent idiopathic scoliosis (AIS), a spine deformity affecting 1-3% of the world population. However, though biomechanical and endocrinological theories have emerged, no clear pathophysiological explanation has been found. Data from the whole-exome sequencing performed on 113 individuals in 19 multi-generational families with AIS have been filtered and analyzed via interaction pathways and functional category analysis (Varaft, Bingo and Panther). The subsequent list of 2566 variants has been compared to the variants already described in the literature, with an 18% match rate. The familial analysis in two families reveals mutations in the BICD2 gene, supporting the involvement of the muscular system in AIS etiology. The cellular component analysis revealed significant enrichment in myosin-related and neuronal activity-related categories. All together, these results reinforce the suspected role of the neuronal and muscular systems, highlighting the calmodulin pathway and suggesting a role of DNA-binding activities in AIS physiopathology.

Loss of CSF-contacting neuron sensory function is associated with a hyper-kyphosis of the spine reminiscent of Scheuermann's disease.

Scheuermann's disease, also referred to as Scheuermann's kyphosis, is the second most frequent spine deformity occurring in humans after adolescent idiopathic scoliosis (AIS), both with an unclear etiology. Recent genetic studies in zebrafish unraveled new mechanisms linked to AIS, highlighting the role of the Reissner fiber, an acellular polymer bathing in the cerebrospinal fluid (CSF) in close proximity with ciliated cells and mechanosensory neurons lining the central canal of the spinal cord (CSF-cNs). However, while the Reissner fiber and ciliary beating have been linked to AIS-like phenotypes in zebrafish, the relevance of the sensory functions of CSF-cNs for human spine disorders remains unknown. Here, we show that the thoracic hyper-kyphosis of the spine previously reported in adult pkd2l1 mutant zebrafish, in which the mechanosensory function of CSF-cNs is likely defective, is restricted to the sagittal plane and is not associated with vertebral malformations. By applying orthopedic criteria to analyze the amplitude of the curvature at the apex of the kyphosis, the curve pattern, the sagittal balance and sex bias, we demonstrate that pkd2l1 knock-outs develop a phenotype reminiscent of Scheuermann's disease. Altogether our work consolidates the benefit of combining genetics and analysis of spine deformities in zebrafish to model idiopathic spine disorders in humans.

Higher femoral anteversion restoration accuracy after total hip arthroplasty with a proximally fixed anatomic stem than with a generic straight double-tapered stem.

BACKGROUND: Femoral antetorsion in uncemented hip replacement hardly can be modified and the restoration of the anatomic anteversion might be difficult with standard stems. We compared femoral anteversion restoration of a generic straight stem with a proximally fixed anatomic stem that included a dual sagittal curvature and a proximal torsion. It was hypothesised that the restoration of the anteversion was more accurate with the anatomic stem. PATIENTS AND METHODS: In this comparative study data were collected prospectively of 80 consecutive patients with total hip arthroplasty for primary osteoarthritis. In the first 40 patients (Group I) a cementless proximally fixed anatomic stem with 15° antetorsion of the shaft and a dual sagittal curvature was used. Its design was based on a database of 3D CT images of 600 hips. For comparison a cementless generic straight double-tapered stem was implanted in the next 40 patients (Group II). All operations were performed by one experienced surgeon. All patients had a preoperative 3D planning. A low-dose CT scan was performed at 3 months postoperatively to determine the postoperative stem anteversion. RESULTS: The demographics were similar in both groups. In group I the mean postoperative femoral anteversion was similar to the preoperative one (22.1° ± 10.2° vs. 20.4° ± 9°; p = 0.2). In Group II, the mean postoperative femoral anteversion was lower (12.9° ± 10.8°, vs. 18.3° ± 12°; p = 0.02). CONCLUSIONS: Uncemented standard femoral stems tend to reduce femoral anteversion. The used anatomic stem restored femoral anteversion better. The clinical impact of this finding has to be proven.

Malpractice litigation after spinal surgery: A review of allegations in France in 1990-2020.

OBJECTIVE: Spinal surgery is among the specialities with the highest rates of complications and of peri-operative morbidity and mortality. The number of spinal surgeries performed is rising year on year in France. The objectives of this study were to identify the main reasons for malpractice claims after spinal surgery in France, to evaluate the impact of avoidable errors, and to examine differences between civil lawsuits (private institutions) and administrative lawsuits (public institutions). HYPOTHESIS: The leading reasons for malpractice litigation are avoidable errors such as inadequate patient information, errors in indications, and inadequate post-operative monitoring. MATERIAL AND METHODS: We reviewed malpractice claims related to spinal surgery and recorded in two French databases (Legifrance and Doctrine) in 1990-2020. We combined the indexing term "surgery" with any of the following terms: "disc", "spine", "cervical", "vertebral", "lumbar", "scoliosis", "disc replacement", and "fusion". The search was performed by three orthopaedic surgeons who were blind to patient data and recorded the allegations, verdicts, and pay-outs. RESULTS: We included 275 claims. The main plaintiff allegations were inadequate information (34.5%), infection (22%), spinal-cord injury (17%), and errors in indication (13%). Among these reasons, 56.7% may have been partly avoidable. In private institutions, claims for infection and for erroneous indication were significantly more common than in public institutions (p=0.02 for both), whereas the opposite was true for spinal-cord injury (p<0.001). CONCLUSION: After spinal surgery in France, the most common malpractice allegation was inadequate information. Over half the claims were related to potentially avoidable factors. Among allegations, errors in indication were significantly more common in civil than in administrative lawsuits. LEVEL OF PROOF: IV, retrospective observational database study.

Efficiency of a novel vertebral body augmentation system (Tektona™) in non-osteoporotic spinal fractures.

BACKGROUND: The restauration of the local kyphosis is crucial to thoracolumbar fractures outcomes. Recently, the Tektona™ (Spine Art) system, constituted by a flexible lamella for corporeal reduction has emerged as a promising solution for osteoporotic fractures. However, no study has yet focused on its results on traumatic fractures. METHODS: A retrospective longitudinal study on prospectively collected data was conducted on 53 patients that had a kyphoplasty by Tektona™, associated or not to percutaneous fixation. The data collected were clinical, surgical and scannographic (measurement of AVH, MVH and PVH (anterior/medium/posterior vertebral height), and RTA (regional traumatic angle) in°), preoperatively, post-operatively and at last follow-up. RESULTS: Fractures were mainly located at the upper lumbar spine and were AOSpine A3 type for 74%. The mean RTA was 12° in pre-operative, 4° in post-operative (p = 2e- 9), and 8° at the last follow-up (p = 0,01). The mean correction of RTA for the fixation group was - 10 ± 6° versus - 7 ± 4° for the kyphobroplasty alone group (p = 0,006). The mean correction for fractures located at T10-T12 was - 9 ± 3°, - 9 ± 5° for L1, - 8 ± 3° for L2 and - 5 ± 3° for L3-L5 (p = 0,045). CONCLUSIONS: The Tektona® system appears to be efficient for acute thoraco-lumbar fractures, comparable to other available systems, allowing a real intracorporeal reduction work. Its relevance, especially in the long term needs further investigation. The association of a percutaneous fixation allow to obtain a better correction of the RTA but did not seem to prevent the loss of correction at follow-up.

Spinal metastases from thyroid cancer: Some prognostic factors.

BACKGROUND: Spinal metastases (SpMs) from thyroid cancers (TC) significantly reduce quality of life by causing pain, neurological deficits in addition to increasing mortality. Moreover, prognosis factors including surgery remain debated. METHODS: Data were stored in a prospective French national multicenter database of patients treated for SpM between January 2014 and 2017. Fifty-one consecutive patients affected by TC with 173 secondary SpM were included. RESULTS: Mean overall survival (OS) time for all patients from the diagnosis of a thyroid SpM event was 9.1 years (SD 8.7 months). The 1-year, 5-year and 10-year survival estimates were 94% (SD 3.3), 83.8.0% (SD 5.2), and 74.5% (SD 9.9). The median period of time between primary thyroid tumor diagnosis and the SpM event was 31.4 months (SD 71.6). In univariate analysis, good ECOG-PS (status 0 and 1) (p < 0.0001), ambulatory status (Frankel score) (p < 0.0001) and no epidural involvement (p = 0.01), were associated with longer survival, whereas cancer subtype (p = 0.436) and spine surgery showed no association (p = 0.937). Cox multivariate proportional hazard model only identified good ECOG-PS: 0 [HR: 0.3, 95% CI 0.1-0.941; p < 0.0001], 1 [HR: 0.8, 95% CI 0.04-2.124; p = 0.001] and ambulatory neurological status: Frankel E [HR: 0.262, 95% CI 0.048-1.443; p = 0.02] to be independent predictors of better survival. CONCLUSION: For cases presenting SpM from TC, we highlighted that the only prognostic factors were the progression of the cancer (ECOG-PS) and the clinical neurological impact of the SpM (Frankel status). Surgery should be discussed mainly for stabilization and neurological decompression.

[Aging of an already pathological spine and its evaluation]. / Vieillissement d'un rachis déjà pathologique et évaluation.

Aging of an already pathological spine and its evaluation. The spine can be subject to different pathologies, starting from the beginning of its growth. Among these, scoliosis is relatively frequent and the question of what happens to unoperated scoliosis patients as they get older and are added to an already patho¬logical spine disc degeneration, posterior osteoarthritis or yellow ligament hypertrophy. The question also arises for other spinal pathologies, such as kyphosis or ankylosing spondylitis: what follow-up should be provided to these patients? What clinical and radiological assessment should be performed?

Vieillissement d'un rachis déjà pathologique et évaluation. Le rachis peut être sujet à différentes pathologies, à partir du début de sa croissance. Parmi celles-ci, la scoliose est relativement fréquente, et la question du devenir des patients scoliotiques non opérés lorsqu'ils avancent en âge et que s'ajoutent sur un rachis déjà pathologique la dégénérescence discale, l'arthrose postérieure ou l'hyper¬trophie du ligament jaune. La question se pose également pour d'autres pathologies rachidiennes, telles que les cyphoses, ou les spondylarthrites ankylosantes : quel suivi faut-il apporter à ces patients ? Quel bilan réaliser ?

Are spine metastasis survival scoring systems outdated and do they underestimate life expectancy? Caution in surgical recommendation guidance.

OBJECTIVE: Survival scoring systems for spine metastasis (SPM) were designed to help surgical practice. The authors sought to validate the prognostic accuracy of the main preoperative scoring systems for SPM. METHODS: It was hypothesized that true patient survival in SPM was better than that predicted using prognosis scores. To investigate this hypothesis, the authors designed a French national retrospective study of a prospectively collected multicenter database involving 739 patients treated for SPM between 2014 and 2017. RESULTS: In this series, the median survival time for all patients from an SPM diagnosis was 17.03 ± 1.5 months. Sensitivity and specificity were estimated using the area under the curve (AUC). The AUC of Tomita's prognosis score was the lowest and poorest (0.4 ± 0.023, range 0.35-0.44), whereas the AUC of the Tokuhashi score was the highest (0.825). The Lei score presented an AUC of 0.686 ± 0.022 (range 0.64-0.7), and the Rades score showed a weaker AUC (0.583 ± 0.020, range 0.54-0.63). Differences among AUCs were all statistically significant (p < 0.001). The modified Bauer score and the Rades score had the highest rate of agreement in predicting survival, with a weighted Cohen's kappa of 0.54 and 0.41, respectively, indicating a moderate agreement. The revised Tokuhashi and Lei scores had a fair rate of agreement (weighted Cohen's kappa = 0.24 and 0.22, respectively). The van der Linden and Tomita scores demonstrated the worst performance, with only a "slight" rate of agreement (weighted Cohen's kappa = 0.19 and 0.16, respectively) between what was predicted and the actual survival. CONCLUSIONS: The use of prognostic scoring systems in the estimation of survival in patients with SPM has become obsolete and therefore underestimates survival. Surgical treatment decisions should no longer be based on survival estimations alone but must also take into account patient symptoms, spinal instability, and quality of life.

The orthopedic characterization of cfap298tm304 mutants validate zebrafish to faithfully model human AIS.

Cerebrospinal fluid (CSF) circulation relies on the beating of motile cilia projecting in the lumen of the brain and spinal cord cavities Mutations in genes involved in cilia motility disturb cerebrospinal fluid circulation and result in scoliosis-like deformities of the spine in juvenile zebrafish. However, these defects in spine alignment have not been validated with clinical criteria used to diagnose adolescent idiopathic scoliosis (AIS). The aim of this study was to describe, using orthopaedic criteria the spinal deformities of a zebrafish mutant model of AIS targeting a gene involved in cilia polarity and motility, cfap298tm304. The zebrafish mutant line cfap298tm304, exhibiting alteration of CSF flow due to defective cilia motility, was raised to the juvenile stage. The analysis of mutant animals was based on micro-computed tomography (micro-CT), which was conducted in a QUANTUM FX CALIPER, with a 59 µm-30 mm protocol. 63% of the cfap298tm304 zebrafish analyzed presented a three-dimensional deformity of the spine, that was evolutive during the juvenile phase, more frequent in females, with a right convexity, a rotational component and involving at least one dislocation. We confirm here that cfap298tm304 scoliotic individuals display a typical AIS phenotype, with orthopedic criteria mirroring patient's diagnosis.

Evaluation of the reduction, tightening and gripping performance of an innovative set screw technology for instrumented posterior lumbar fusion: A biomechanical study.

BACKGROUND: Instrumented posterior lumbar fusion with top-loading pedicle screw systems (PSS) requires fully tightened set screws to achieve a secure fixation and symmetric load condition. This assumes a complete reduction of the rod by 90°, which is not always attainable in situ, especially under constraint. The objective of this work is to compare the mechanical performance of different innovative set screw technologies, which should improve the tightening process. HYPOTHESIS: The hypotheses of the study are that modifications to the screw and screwdriver unit can (1) improve the quality of set screw tightening and (2) increase the axial gripping capacity of the construct. MATERIALS AND METHODS: The four set screw technologies under investigation include a standard set screw with a flat surface (F-S; control group), a set screw with a convex surface (C-S) and a shaft tip method screwdriver used in combination with both flat (F-STM) and convex set screws (C-STM). The quality of set screw tightening is categorized as follows: failed=the rod is not completely reduced; reduced=the rod is successfully reduced but the set screw is not correctly fixed; good=remaining cases. An axial gripping capacity test is performed by a universal testing machine (Instron®) with a force capacity of 5kN. RESULTS: Regarding the quality of set screw tightening, comparisons between F-S vs. F-STM, F-S vs. C-STM and between C-S vs. C-STM show statistically significant differences (p<0.001). The axial gripping capacity test shows mean gripping forces of 1223N (STD 331) in the F-STM group and of 1724N (STD 168) in the C-STM group with statistically significant differences between both groups (p=0.003). DISCUSSION: Several biomechanical and clinical case studies have identified possible effects of misaligned rod-screw interfaces such as screw pull-out during rod reduction, screw loosening, screw or rod breakage, misalignment, adjacent segment degeneration and worsening of the clinical outcome. C-STM-technology thus supports controlled fixation in the sense of applying appropriate forces for correction or fixation during PSS assembly as well as friction-reduced final alignment and tightening with the aim to reduce implant loosening, hardware failure and reoperations, while respecting anatomical and biomechanical balance.

Height and volume restoration in osteoporotic vertebral compression fractures: a biomechanical comparison of standard balloon kyphoplasty versus Tektona® in a cadaveric fracture model.

BACKGROUND: Standard balloon kyphoplasty represents a well-established treatment option for osteoporotic vertebral compression fractures. Aim of the present study was to evaluate two different methods of percutaneous augmentation (standard balloon kyphoplasty (BKP) versus Tektona® (TEK)) with respect to height restoration. METHODS: Four-teen vertebral bodies of two female cadavers were examined. Fractures were created using a standardized protocol. CT-scans were taken before and after fracture, as well as after treatment. Afterwards two groups were randomly assigned in a matched pair design: 7 vertebral bodies (VB) were treated with BKP (Kyphon, Medtronic) and 7 vertebral bodies by TEK (Spineart, Switzerland) Anterior, central and posterior vertebral body heights were evaluated by CT-scans. Volumetry was performed using the CT-scans at three different timepoints. RESULTS: Values before fracture represent 100%. The anterior height after fracture was reduced to 75.99 (± 4.8) % for the BKP group and to 76.54 (± 9.17) % in the TEK Group. Statistically there was no difference for the groups (p = 1). After treatment the values increased to 93.06 (± 5) % for the BKP Group and 87.71 (± 6.2) % for the TEK Group. The difference before and after treatment was significant for both groups (BKP p = 0.0006; TEK p = 0.03). Within the groups, there was no difference (p = 0.13). The Volume of the vertebral body was reduced to 82.29 (± 8.4) % in the BKP Group and to 76.54 (± 8.6) % in the TEK Group. After treatment the volume was 89.26 (± 6.9) % for the BKP Group and 88.80 (± 8.7) % for the TEK Group. The difference before and after treatment was significant only for the TEK group (BKP p = 0.0728 n.s.; TEK p = 0.0175). Within the groups, there was no difference (p = 0.2). The average cement volume used was 6.1 (range 3.6-9 ml) for the BKP group and 5.3 (3-7.2 ml) for the TEK group respectively. CONCLUSIONS: Based on our results the new System Tektona® in osteoporotic compression fractures might represent a promising alternative for the clinical setting, especially preserving bone. Further biomechanical tests and clinical studies have to proof Tektona®`s capabilities.

Spine Metastasis in Elderly: Encouraging Results for Better Survival.

MINI: The incidence of spinal metastasis (SpM) is increasing, and life expectancy for patients with malignancy is also rising. The "elderly" represent a population with steady growth in SpM proportion. Bracing is associated with lower survival. We believe that surgery should be considered, regardless of the patient's age.

Multicentric prospective study. Through this study, we aimed to clarify and update the prognostic assessment of elderly with spine metastasis (SpM). The incidence SpM is rising, in parallel life expectancy is getting longer and the number of elderly patients presenting malignancy is increasing. Elderly patients with SpM constitute a growing heterogeneous population The patient data used in this study were obtained from a French national multicenter database of patients treated for SpM between 2014 and 2017. Two hundred and forty-three consecutive patients >70 years' old were diagnosed. Median overall survival (OS) time for elderly patients following the event of SpM was 16.3 months. First, we identified significantly worse survival prognostic factors for elderly patients with SpM: poor WHO status 3/4: (hazard ratio [HR]: 2.245, 95% confidence interval [CI] 1.899­2.655; P  < 0.0001), >80 years (HR: 1.758, 95% CI 1.117­2.765; P  = 0.015) no-ambulatory neurological status (Franckel A/B status [HR: 3.219, 95% CI 1.621­6.390; P  < 0.0001)], gastrointestinal cancer (HR: 3.530, 95% CI 1.75­7.1; P  < 0.0001), lung cancer (HR: 3.452, 95% CI 1.784­6.680; P  < 0.0001), orthopedic brace treatment (HR: 1.329; 95% CI 1.050­1.683; P  = 0.018), and epiduritis (HR: 1.52, 95% CI 1.041­2.22; P  = 0.03) were independently poor prognostic factors of survival. The only good prognosis factor identified was thyroid cancer (HR: 0.257, 95% CI 0.07­0.952; P  = 0.04). Prognosis factors concerning the survival of elderly patients seem to be the same as those for the general population such as primary cancer histology, neurological status, WHO status, and epiduritis. Age >80 years also appears to be an independently poor prognosis factor. Our data suggest that orthopedic brace treatment is also associated with lower survival. Level of Evidence: 2.

Spine metastasis in patients with prostate cancer: Survival prognosis assessment.

BACKGROUND: Patients presenting spine metastasis (SpM) from prostate cancer (PC) form a heterogeneous population, through this study, we aimed to clarify and update their prognostic assessment. METHODS: The patient data used in this study was obtained from a French national multicenter database of patients treated for PC with SpM between 2014 and 2017. A total of 72 patients and 365 SpM cases were diagnosed. RESULTS: The median overall survival time for all patients following the event of SpM was 28.8 months. First, we identified three significant survival prognostic factors of PC patients with SpM: good Eastern Cooperative Oncology Group/World Health Organization personnel status (Status 0 hazard ratio [HR]: 0.031, 95% confidence interval [CI]: 0.008-0.127; p < .0001) or (Status 1 HR: 0.163, 95% CI: 0.068-0.393; p < .0001) and SpM radiotherapy (HR: 2.923, 95% CI: 1.059-8.069; p < .0001). Secondly, the presence of osteolytic lesions of the spine (vs. osteoblastic) was found to represent an independent prognosis factor for longer survival [HR: 0.424, 95% CI: 0.216-0.830; p = .01]. Other factors including the number of SpM, surgery, extraspinal metastasis, synchrone metastasis, metastasis-free survival, and SpM recurrence were not identified as being prognostically relevant to the survival of patients with PC. CONCLUSION: Survival and our ability to estimate it in patients presenting PC with SpM have improved significantly. Therefore, we advocate the relevance of updating SpM prognostic scoring algorithms by incorporating data regarding the timeline of PC as well as the presence of osteolytic SpM to conceive treatments that are adapted to each patient.

Sacrum osteotomy to change pelvic parameters: Surgical technique and 3D modeling.

PURPOSE: Some clinical situations, such as great sagittal imbalance, high-grade isthmic spondylolisthesis or sacral malunion could require a sacral osteotomy to decrease pelvic parameters, horizontalize the sacrum or correct sacral malunion. Here is described a novel technique to perform a sacral osteotomy to decrease pelvic parameters with a lumbo-pelvic construct, with first a sacral slope decrease, then a pelvic tilt decrease. METHODS: Simulations have been performed using tridimensional reconstructions of the lumbar spine and pelvis, made from CT-scan images of a healthy individual. A cadaveric study has then been performed. RESULTS: 3D modeling exhibited linear relationship between osteotomy angle and pelvic incidence correction, through multiple simulations with 1° increment. Cadaveric study demonstrated feasibility. CONCLUSION: This preliminary work shows that this technique is efficient to decrease pelvic parameters. A linear relationship has been exhibited between osteotomy angle and PI decrease, as per the following formula: osteotomy angle=PI change/0.84.

Spinal metastases from lung cancer: Survival depends only on genotype, neurological and personal status, scarcely of surgical resection.

BACKGROUND: For patients with non-small cell lung cancer (NSCLC), the spinal column is the most common site for bone metastasis. Studies that assess survival prognostic factors associated with specific lung spinal metastases (SpM) are weak and required the incorporation of genotype mutations. METHODS: A prospective French national multicenter database of patients treated for SpM between January 2014 and 2017.818 lung SpM were diagnosed over the course or at the time of diagnosis of 210 consecutive patients with NSCLC. RESULTS: Median overall survival (OS) time for all patients from the lung SpM event was 5.9 months (SD 0.609). For 122 patients (61%), lung tumor and SpM were diagnosed synchronously. In univariate analysis, good World Health Organisation (WHO) status (p < 0.0001), ambulatory status (Frankel score) (p < 0.0001), the absence of spine epiduritis (p < 0.0001), immunotherapy after SpM diagnosis (p < 0.0001), ALK gene rearrangement (p < 0.0001) and EGFR mutation (p < 0.0001) were associated with longer survival, whereas spine surgery showed no association (0.141). Cox multivariate proportional hazard model identified that EGFR + status (HR: 0.339, 95% CI 0.166-0.693; p = 0.003), good WHO status (p < 0.0001) and good neurological status (Frankel E; p < 0.001 and D; p = 0.018) were associated with higher median OS. Whereas the other factors, including ALK + status, epiduritis and immunotherapy were not independent prognostic factors of survival. CONCLUSION: Survival in SpM must be prognosticated from general health performance status: clinical (WHO) and neurological (Frankel) as well as the EGFR mutation status. Immunotherapy, surgery and epiduritis have not demonstrated prognostic value. Therefore, surgical prognostic scoring algorithms should incorporate genotype subtypes in NSCLC cancers to adapt surgical treatment.

Evaluation of disc degeneration adjacent to AOspine A fractures: pre- and post-operative MRI analysis.

INTRODUCTION: The management of type A thoracolumbar fractures varies from conservative treatment to multiple level fusion. Indeed, although Magerl defined the type A fracture as a strictly bone injury, several authors suggested associated disc lesions or degeneration after trauma. However, the preservation of mobility of the adjacent discs should be a major issue. This study was conducted to analyze the presence of immediate post-traumatic disc injuries and to know if discs degenerate after receiving treatment. METHODS: We retrospectively reviewed the files of 27 patients with an AOspine A fracture, corresponding to 34 fractures (64 discs) with pre and post-operative MRI (mean follow-up: 32.4 months). Based on Pfirrmann's and Oner's classifications of disc injuries, two observers analyzed independently the type of lesion in the discs adjacent to the fractured vertebra in immediate post-trauma and at the last follow-up. RESULTS: The immediate post-traumatic analysis according to Pfirrmann's classification found 97% of the cranial adjacent discs and 100% of the caudal discs classified Pfirrmann 3 or less. The analysis on the secondary MRI revealed that 78% of cranial adjacent discs and 88% of caudal adjacent discs still were classified Pfirrmann 3 or less. CONCLUSIONS: Since, the great majority of type A fractures does not cause immediate disc injuries, these fractures are, as described by Magerl, strictly bony injuries. The quality of the body reduction seems to prevent secondary degeneration. These results may encourage surgeons not to perform arthrodesis on type A fractures even for A3 and A4.