Literatura académica sobre el tema "Kyphotic index and QTrac©"

Spinal deformity in the form of kyphosis or kyphoscoliosis occurs in most patients with Duchenne muscular dystrophy (DMD), a fatal X-linked disorder caused by an absence of the subsarcolemmal protein dystrophin. Mdx mice, which also lack dystrophin, show thoracolumbar kyphosis that progresses with age. We hypothesize that paraspinal and respiratory muscle weakness and fibrosis are associated with the progression of spinal deformity in this mouse model, and similar to DMD patients there is evidence of altered thoracic conformation and area. We measured kyphosis in mdx and age-matched control mice by monthly radiographs and the application of a novel radiographic index, the kyphotic index, similar to that used in boys with DMD. Kyphotic index became significantly less in mdx at 9 mo of age (3.58 ± 0.12 compared with 4.27 ± 0.04 in the control strain; P ≤ 0.01), indicating more severe kyphosis, and remained less from 10 to 17 mo of age. Thoracic area in 17-mo-old mdx was reduced by 14% compared with control mice ( P ≤ 0.05). Peak tetanic tension was significantly lower in mdx and fell 47% in old mdx latissimus dorsi muscles, 44% in intercostal strips, and 73% in diaphragm strips ( P ≤ 0.05). Fibrosis of these muscles and the longissimus dorsi, measured by hydroxyproline analysis and histological grading of picrosirius red-stained sections, was greater in mdx ( P < 0.05). We conclude that kyphotic index is a useful measure in mdx and other kyphotic mouse strains, and assessment of paralumbar and accessory respiratory muscles enhance understanding of spinal deformity in muscular dystrophy.

Correction of posttraumatic deformity and stabilization of injured segment play an important role in treatment and complication prevention after traumatic compression vertebral body fractures. Possibilities of deformity reduction using vertebroplasty and a combination of distractive titanium cage with insertion of bone cement into vertebral body (stenoplasty) are not well studied. Retrospective comparative analysis of clinical efficacy and degree of kyphotic deformity reduction using puncture vertebroplasty (1 st group, n=15) and stenoplasty (2 nd group, n=15) in patients with traumatic A1 compression fractures of thoraco-lumbar vertebral bodies was performed. Severity of pain syndrome (VAS) and degree of injured segment deformity (kyphotic angle and wedge-shaping index) were assessed. In both groups surgical intervention resulted in marked pain reduction but in long-term period it was less significant for 2 nd group (p=0.0035). Postoperatively kyphotic angle median and wedge-shaping index changed statistically significant in 2 nd group from 12.60 (10.50; 13.40) to 2.50 (1.90; 3.20) (p=0.0015) and from 25.3% (22.8; 26.7) to 9.3% (8.9; 11.4) (p=0.0022), respectively and not significantly in 1 st group from 13.10 (11.40; 14.30) to 12.90 (11.20; 14.00) (p= 0.93) and from 26.5% (24.0; 28.8) to 25.9% (23.8; 28.4) (p=0.86), respectively. Progression of posttraumatic kyphosis in late postoperative period was noted in 1 st group (P M Ü=0.042) but not in 2nd group (P =0.58). In traumatic A1 compression fractures stenoplasty enabled to perform kyphotic deformity correction in the early period of spinal injury, to achieve significantly greater reduction of kyphotic angle and to preserve the result in remote postoperative period as compared to puncture vertebroplasty

OBJECTIVELate-onset neurological deficits are a rare complication of spinal tuberculosis that may be caused by proximal adjacent segment degeneration (ASD) above the kyphus. The objective of this study was to report several cases of neurological deficits due to proximal ASD in patients with post-tuberculous kyphotic deformity and discuss the characteristics of the authors’ corrective surgical technique.METHODSThe inclusion criteria in this study were severe angular kyphosis due to a post-tuberculous kyphotic deformity and a late-onset neurological deficit. The cause of these deficits was related to a lesion in the proximal cephalad portion of the kyphotic deformity. Surgical intervention, including decompression and compromised restoration of the sagittal imbalance, was performed in all patients. Preoperative surgical planning with a radiological evaluation included CT, plain radiograph, and MRI studies. Clinical outcomes were evaluated using the American Spinal Injury Association Impairment Scale and the Oswestry Disability Index (ODI).RESULTSThe main goal of our surgical technique was the correction of sagittal malalignment by positioning the patient’s head above the kyphotic deformity on the sagittal plane, excluding aggressive osteotomy. The neurological symptoms showed immediate improvements postoperatively, except in 1 patient. Compared to the preoperative value of 66.9, the mean ODI score improved to 42.6 at the final follow-up for all patients. Preoperatively, the mean values of the angles of deformity and the sagittal vertical axis were 99.7° and 157.7 mm, respectively, and decreased to 75.3° and 46.0 mm, respectively, at the final follow-up. No major complications were observed, and the patients’ self-satisfaction was high with respect to both cosmetic and functional outcomes.CONCLUSIONSClinicians should be aware of the degeneration of the vertebrae above the kyphotic segment in patients with post-tuberculosis deformity. Successful neurological recovery and compromised sagittal balance could be obtained by using our “head on kyphus” surgical concept.

In order to compare short-segment stabilization with long-segment stabilization for treating unstable thoracolumbar fractures, we studied fifty patients suffered from unstable thoracolumbar burst fractures. Thirty of them were managed with long-segment posterior transpedicular instrumentation and twenty patients with short- segment stabilization. The mean follow up period was 5.2 years. Pre-operative and post-operative radiological parameters, like the Cobb angle, the kyphotic deformation and the Beck index were evaluated. A statistically significant difference between the two under study groups was noted for the Cobb angle and the kyphotic deformation, while, as far as the Beck index is concerned, no significant difference was noted. In conclusion, either the long-segment or the short-segment stabilization is able for reducing the segmental kyphosis and the vertebral body deformation postoperatively. However, as time goes by, the long-segment stabilization is associated with better results as far as the radiological parameters, the indexes and the patient’s satisfaction are concerned.

Object Recurrent kyphosis has been commonly seen after posterior short-segment pedicle instrumentation for a thoracolumbar fracture, but studies on this issue are relatively scarce, and the clinical significance of recurrent deformity is uncertain. No study has addressed the associations between the reduction of a burst fracture vertebra and the final recurrent kyphosis after implant removal. The aim of this study was to investigate the recurrent kyphosis after short-segment pedicle screw fixation in thoracolumbar burst fractures and to evaluate the effect of the degree of a vertebral reduction on the recurrent kyphotic deformity after implant removal. Methods Twenty-seven patients who had undergone posterior short-segment pedicle screw fixation for thoracolumbar junction burst fractures (T12–L2) were investigated retrospectively. The minimum follow-up period was 2 years (mean 2.7 years). Pain status was evaluated using the Denis pain scale. Changes in the anterior vertebral height ratio, vertebral wedge angle, upper intervertebral angle, lower intervertebral angle, Cobb angle, regional angle, and sagittal index were measured preoperatively, postoperatively, before implant removal, and at final follow-up. The correlation between the reduction of a fractured vertebra and the recurrent kyphotic deformity was also analyzed. Results After the initial surgical correction, the reduced vertebral body (VB) height (anterior vertebral height ratio and vertebral wedge angle) remained stable until final follow-up, whereas the intervertebral disc space (the upper and lower intervertebral angles) collapsed, resulting in a progressive kyphotic deformity (Cobb angle, regional angle, and sagittal index). No significant correlation was found between the final kyphosis and pain scale, but the 8 patients with a sagittal index > 15° showed a higher incidence of moderate to severe pain (P3–5 on the Denis pain scale) compared with the remaining 19 patients with a sagittal index < 15°. Significant positive correlation was found between recurrent kyphosis and vertebral wedge angle (r = 0.850, p < 0.001) and the reduced vertebral height (r = −0.727, p < 0.001). Conclusions Given that the correction loss occurs primarily through disc space collapse, the amount of the final kyphotic deformity was predictable by the degree of the fractured vertebral reduction as seen on the lateral x-ray study. Surgeons who perform posterior reduction and fixation procedures should pay more attention to reducing the fractured vertebral wedge angle to its intact condition, rather than the segmental angular parameters. If the wedge angle of the fractured VB is unacceptable after reduction, additional reconstruction of the anterior column may be necessary.

Purpose. The purpose of our study is to evaluate the therapeutic efficacy of short-segment percutaneous pedicle screw fixation with polymethylmethacrylate (PMMA) augmentation for the treatment of osteoporotic thoracolumbar compression fracture with osteonecrosis.Methods. Osteoporotic thoracolumbar compression fractures with avascular necrosis were treated by short-segment PPF with PMMA augmentation. Eighteen were followed up for more than 2 years. The kyphotic angle, compression ratio, visual analog scale (VAS) score for back pain, and the Oswestry Disability Index (ODI) were analyzed. In addition, radiologic and clinical parameters of PPF group were compared with percutaneous vertebroplasty (PVP) group.Results. Vertebral height and kyphotic angle of the compressed vertebral bodies were significantly corrected after the operation (P<0.05). Further, restored vertebral height was maintained during the 2 or more years of postoperative follow-up. Compared to the PVP group the postoperative compression ratio and kyphotic angle were significantly lower in the PPF group (P<0.05). The postoperative ODI and VAS of the PVP group were significantly higher than the PPF (P<0.05).Conclusions. According to our results, short-segment PPF with PMMA augmentation may be an effective minimally invasive treatment for osteoporosis in cases of osteoporotic vertebral compression fractures with Kummell’s osteonecrosis.

Object In this paper, the authors' goal was to evaluate the feasibility, safety, and efficacy of apical segment resection osteotomy with dual axial rotation correction for severe focal kyphosis by examining outcomes. Methods Between May 2004 and December 2006, the authors treated 23 patients with severe focal kyphosis (average Cobb angle 86.9°, range 50°–130°) using apical segmental resection osteotomy with dual axial rotation correction and instrumented anterior column reconstruction and fusion. Radiographic assessment of sagittal plane balance and kyphotic Cobb angle (including a scoliosis Cobb angle in 9 cases) was performed in each patient before and immediately after surgery and at the last follow-up (minimum 2 years). The Frankel grading system for neurological function and Oswestry Disability Index for quality of life were evaluated before surgery and at the last follow-up. The patient satisfaction index was also used for clinical evaluation at the last follow-up. Results The mean surgical time was 6.7 hours. The average blood loss was 2960 ml. All patients underwent follow-up for 2 or more years after surgery. The fusion rate was 95.65%. The average kyphotic angle improved from 86.9° preoperatively to 25.6° immediately postoperatively, with an average correction rate of 72.17%. At the last follow-up, the average kyphotic angle was 27.4°, making the final correction rate 69.87%. The sagittal plane balance was significantly improved at the last follow-up. Preoperatively, 15 patients had neurological deficits, and the Frankel grade was E in 8 cases, D in 8 cases, C in 6 cases, and B in 1 case. At the last follow-up, 15 cases were Grade E, 5 were Grade D, and 3 were Grade C. The average improvement in the Oswestry Disability Index score was 43.30%. The patient satisfaction index result showed a total satisfaction rate of 91.30%. Complications included 1 case of late neurological deficit due to shifting of an expandable artificial vertebra, 5 cases of nerve root injury, 3 cases of dural tear, and 1 case of transient lower-extremity weakness due to insufficient blood supply to the spinal cord during surgery. Conclusions Apical segmental resection osteotomy with dual axial rotation correction and instrumented fusion is an effective and safe way to treat severe focal kyphosis of the thoracolumbar spine.

Objective To investigate the differences of spinal curvature, thoracic sagittal mobility, and respiratory strength between patients with chronic neck pain (CNP) and people without cervical pain, and to determine the correlation between respiratory strength and thoracic mobility in CNP patients.Methods A total of 78 participants were finally included in this study, of whom 30 had no cervical pain and 48 had CNP. The Neck Disability Index (NDI), cervical lordotic curvature, thoracic kyphotic curvature, thoracic sagittal range of motion (ROM), maximal inspiratory pressure (MIP), and maximal expiratory pressure (MEP) were measured and analyzed.Results In males, thoracic sagittal ROM_MEP-MIP and MEP showed a significant difference between the no cervical pain group and the CNP group. In females, thoracic kyphotic curvature, thoracic sagittal ROM_MEP-MIP, MIP, and MEP were significantly different between the no cervical pain group and the CNP group. Thoracic kyphotic curvature was significantly correlated with MEP and MIP in all population groups, and significantly correlated with NDI in the female group. Thoracic sagittal ROM_MEP-MIP had a significant linear relationship with NDI, MEP, and MIP in all population groups.Conclusion The thoracic mobility during forced respiration was reduced in patients with CNP and was correlated with respiratory strength. Changes in the biomechanics of the cervicothoracic spine and rib cage due to CNP may contribute to impairment of respiratory strength.

Objective To evaluate the influence of insufficient bone cement distribution on outcomes following percutaneous vertebroplasty (PVP). Methods This retrospective matched-cohort study included patients 50–90 years of age who had undergone PVP for single level vertebral compression fractures (VCFs) from February 2015 to December 2018. Insufficient (Group A)/sufficient (Group B) distribution of bone cement in the fracture area was assessed from pre- and post-operative computed tomography (CT) images. Assessments were before, 3-days post-procedure, and at the last follow-up visit (≥12 months). Result Of the 270 eligible patients, there were 54 matched pairs. On post-operative day 3 and at the last follow-up visit, significantly greater visual analogue scale (VAS) pain scores and Oswestry Disability Index (ODI) scores were obtained in Group B over Group A, while kyphotic angles (KAs) and vertebral height (VH) loss were significantly larger in Group A compared with Group B. Incidence of asymptomatic cement leakage and re-collapse of cemented vertebrae were also greater in Group A compared with Group B. Conclusions Insufficient cement distribution may relate to less pain relief and result in progressive vertebral collapse and kyphotic deformity post-PVP.

Object Cervical arthroplasty offers the promise of maintaining motion of the functional spinal unit (FSU) after anterior cervical discectomy. The impact of cervical arthroplasty on sagittal alignment of the FSU needs to be addressed, together with its effect on overall sagittal balance of the cervical spine. Methods The authors prospectively reviewed radiographic and clinical outcomes in 14 patients who received the Bryan Cervical Disc prosthesis (Medtronic Sofamor Danek, Memphis, TN), for whom early (< 6 months) and late (6–24 months) follow-up data were available. Static and dynamic radiographs were measured by hand and computer to determine the angles formed by the endplates of the natural disc preoperatively, those formed by the shells of the implanted prosthesis, the angle of the FSU, and the C2–7 Cobb angle. The range of motion (ROM) was also determined radiographically, whereas clinical outcomes were assessed using the Neck Disability Index (NDI), and Short Form–36 (SF-36) questionnaires. The ROM was preserved following surgery, with a mean preoperative sagittal rotation angle of 8.96°, which was not significantly different from the late postoperative value of 8.25°. When compared with the preoperative disc space angle, the shell endplate angle in the neutral position became kyphotic in the early and late postoperative periods (mean change −3.8° in the late follow-up period; p = 0.0035). The FSU angles also became significantly more kyphotic post-operatively, with a mean change of −6° (p = 0.0006). The Cobb angles varied widely preoperatively and did not change significantly after surgery. There was no statistical correlation between the NDI and SF-36 outcomes and cervical kyphosis. Conclusions Cervical arthroplasty preserves motion of the FSU. Both the endplate angle of the treated disc space and the angle of the FSU became kyphotic after insertion of the Bryan prosthesis. The overall sagittal balance of the cervical spine, however, was preserved.

La dystrophie musculaire de Duchenne est une maladie neuromusculaire qui touche 1 enfant sur 3500, liée au chromosome X, caractérisée par l’absence de dystrophine, protéine située sous le sarcolemme qui confère stabilité à la membrane cellulaire en connectant l’actine du cytosquelette avec la matrice extracellulaire. Elle fait partie d’un complexe multi protéique, nommé « dystrophin associated protein complex (DAPC)», qui contient, entre autre, le -dystroglycane et l’oxyde nitrique synthase (NOS). Son absence cause la dérégulation de l’homéostasie calcique, la nécrose tissulaire, l’accumulation de tissu graisseux et fibreux, l’incapacité de mouvement et des déficits cardiaques et respiratoires qui aboutissent au décès des patients. Mon travail avait comme objectif l’amélioration de différents aspects du phénotype dystrophique. J’ai utilisé des molécules capables d’activer deux voies de signalisations (la voie du NO et l’inhibition des histones deacetylase (HDAC)), connues pour induire l’amélioration du phénotype dystrophique chez la souris mdx, modèle de la maladie. Plus particulièrement, j’ai testé chez la souris, deux mode d’administration du butyrate d’arginine (AB), la drogue de référence car déjà utilisée en clinique sur des jeunes patients pour une autre indication, par gavage et par injection intrapéritonéale. J’ai étudié aussi deux nouvelles molécules dérivées du AB, qui pourraient être administrées par voie orale et être efficace à faible dose : le 3-Hydroxybutyrate arginate (ABE) et le N-butyril arginine (ABA). AB, ABE et ABA ont été testés in vitro sur les myotubes de patients dystrophiques et in vivo sur des souris mdx. L’administration orale du AB a les mêmes effets positifs que l’injection intrapéritonéale chez les souris mdx. Ces résultats démontrent que l’administration par voie orale doit être prise en considération lors des futurs essais cliniques. Dans un deuxième temps, je me suis focalisée sur les défauts cardiaques. Un suivi par échocardiographie mensuelle a été réalisé sur des souris de 8 mois traitées avec du AB. En parallèle nous avons analysé les effets de l’administration par voie orale du AB sur les déformations de la colonne vertébrale. Enfin, les altérations des signaux de l’électromyogramme (réalisé avec une méthode non invasive développée en clinique et appliquée pour les animaux) ont été également analysées. L’ensemble des résultats obtenus montre que le AB est capable de préserver l’activité cardiaque, d’empêcher la déformation de la colonne vertébrale et de rétablir les paramètres d’excitabilité axonale mesurés chez les souris traitées.Différentes concentrations des ABE et ABA ont été testé in vivo et observé à des faibles doses les mêmes résultats bénéfiques sur de nombreux paramètres structuraux et fonctionnels, que ceux obtenu avec une dose importante de AB (800mg/kg/j). Les deux nouvelles drogues peuvent être administrées à une dose 10 fois inferieur que la dose de AB pour obtenir les mêmes effets. J’ai testé aussi in vitro, sur des cellules musculaires humaines, la capacité des deux produits à induire une augmentation des niveaux intracellulaires d’utrophine et des protéines associées (β-dystroglycan et la myosine embryonnaire). J’ai aussi démontré qu’une augmentation de l’expression de l’utrophine et des protéines associées pouvait être induite par les inhibiteurs d’HDAC (le butyrate, la trichostatine A, l’acide valproique et l’isobutyramide). Enfin, une étude portant sur l’homéostasie calcique a été réalisé car des altérations de cet équilibre sont en partie responsables de la nécrose/dégénérescence du tissue musculaire. En particulier, l’activité spontanée du Ca2+, enregistrée sur le myotubes humaine, été fortement réduite après un traitement agissant sur la voie d’activation du NO et/ou par des inhibiteurs des HDAC. L’ensemble des résultats obtenus apportent la preuve des effets bénéfiques du AB et de ses dérivés sur la DMD, a travers la voie du NO et en inhibant les HDAC
Duchenne muscular dystrophy is a X-linked progressive neuromuscular disease affecting 1:3500 boys at birth. It is caused by the absence of dystrophin, a subsarcolemmal protein that confers membrane stability linking cytoskeletal actin to the extracellular matrix. It is part of a multi-protein complex called dystrophin associated protein complex (DAPC), which contains, among the other components, -dystroglycan and nitric oxide synthase (NOS).The consequences of the absence of dystrophin are: deregulation of calcium homeostasis, tissues necrosis, progressive accumulation of fat and fibrosis, inability of the movements and cardiac and respiratory failures that lead to patient’s death, around the age of 20-30 years.The objective of my PhD work is to ameliorate different aspects of dystrophic phenotype. In particular I have tested two different ways of administration of arginine butyrate (AB), the reference drug, through feeding-force and intraperitoneal injection. Meanwhile I have studied two new pharmacological molecules, AB derived, which could be administered orally to DMD patients. These compounds are: 3-Hydroxybutyrate arginate (refer as ABE) and N-butyryl arginine (refer as ABA). All of these molecules partially restore dystrophic phenotype activating two independent pathways (both the nitric oxide pathway and the inhibition of the histone deacetilase), which are known to be beneficent for mdx mice.AB, ABE and ABA have been tested in vitro on human DMD myotubes and in vivo on the mdx mice. The first goal of my project is the observation that the positive effects obtained after intraperitoneal injections of AB can be detected also after oral protocol, promoting the idea that the oral way has to be developed for future clinical trials. I have focused my attention on heart defaults; in particular, starting from the 8th month, a monthly study on heart activity based on echocardiography has been performed on mdx mice treated with AB. We addressed the potential profits of the oral administration of arginine butyrate on vertebral column deformation and electromyogram defaults, with a non-invasive automatized method developed in clinic and then applied to animals. The results collected from these experiments show that AB preserve heart activity, reverse vertebral column deformity and all the axonal excitability parameters that were modified in saline-treated mdx mice.In complement, I have tested different concentrations of ABE and ABA in vivo. The positive effects on many structural and functional dystrophic parameters, previously obtained with high dose of AB administered per os (800 mg/kg/d), has been observed with doses 10 times lower with both new compounds.In parallel, both products were tested in vitro on human muscular cells cultures to investigate their capacity to increase utrophin level. Moreover, the potential ability of histone deacetylase inhibitors (byturate, valproic acid, trichostatin A and isobutyramide) to increase the expression of utrophin and related proteins (-dystroglycan and embryonic myosin) has been studied. Finally, the alteration of calcium homeostasis, largely implicated in the cascades resulting in muscle necrosis/degeneration, was investigated. The spontaneous Ca2+ activity recorded in patient myotubes, i.e. without sarcolemmal integrity was strongly reduced after treatment acting on the NO-pathway activation and/or with HDAC inhibitors. All together, these data constitute a proof of principle of the beneficial effects of arginine butyrate and its derivates on muscular dystrophy, by enhancing NO pathway and inhibiting HDAC