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1.
Pain ; 164(8): 1734-1740, 2023 Aug 01.
Article in English | MEDLINE | ID: mdl-36661188

ABSTRACT

ABSTRACT: Spinal disorders are the main reasons for sick leave and early retirement among the working population in industrialized countries. When "red flags" are present, spine surgery is the treatment of choice. However, the role of psychosocial factors such as fear-avoidance beliefs in spine surgery outcomes is still debated. The study aims to investigate whether patients presenting high or low levels of fear-avoidance thoughts before the spine surgery reported different surgical results and return-to-work rates over 2 years. From an institutional spine surgery registry, workers surgically treated with a preoperative score in the Oswestry Disability Index (ODI) higher than 20/100 and provided ODI questionnaires, return-to-work status at 3-, 6-, 12-, and 24-month follow-ups were analyzed. A total of 1769 patients were stratified according to the work subscale of the Fear-Avoidance Beliefs Questionnaire (FABQ-W) in high fear (FABQ-W ≥ 34/42) or low fear (FABQ-W < 34/42). Multivariate regression was used to search for preoperative factors, which might interact with FABQ-W. The higher-fear group showed a different recovery pattern, with higher levels of disability according to the ODI (total score, absolute change, frequency of clinically relevant change, and disability categories) and lower return-to-work ratios over the 24-month follow-up. High fear, high disability, greater age, female gender, smoking, and worse physical status at baseline were associated with worse ODI outcomes 2 years after the surgery. In summary, fear-avoidance beliefs significantly influence the speed and the entity of surgical outcomes in the working population. However, the contribution of FABQ-W in predicting long-term disability levels was limited.


Subject(s)
Employment , Fear , Humans , Female , Follow-Up Studies , Fear/psychology , Surveys and Questionnaires , Return to Work , Disability Evaluation
2.
Spinal Cord Ser Cases ; 8(1): 84, 2022 10 14.
Article in English | MEDLINE | ID: mdl-36241621

ABSTRACT

INTRODUCTION: The risk of spinal cord damage after Spinal Cord Stimulator (SCS) implant is a very rare event. In our case report, the patient was affected by a progressively worsening spinal stenosis due to SCS compression. CASE REPORT: The authors describe a progressive paraparesis in a 58-year-old woman with a long history of back pain and multiple spine surgeries. Computed tomography (CT) outlined vertebral canal stenosis corresponding to an electrode array implanted in T9. A posterior T8-T10 spinal cord decompression with explanation of the SCS device was performed and a partial neurological improvement was observed immediately postoperative. DISCUSSION: Spinal cord stimulation has been used since 1967 for the treatment of refractory chronic pain, particularly failed back surgery syndrome (FBSS) and complex regional pain syndrome (CRPS). Still, the mechanism underlying its function is not completely clear. Moreover, complications are mainly related to implant dysfunction and the risk of direct and indirect spinal cord compression is described as exceptional in the literature. Our aim is to describe the case SCS device spinal cord direct compression and its surgical treatment.


Subject(s)
Complex Regional Pain Syndromes , Failed Back Surgery Syndrome , Spinal Cord Compression , Spinal Cord Stimulation , Spinal Stenosis , Complex Regional Pain Syndromes/complications , Complex Regional Pain Syndromes/therapy , Failed Back Surgery Syndrome/complications , Failed Back Surgery Syndrome/therapy , Female , Humans , Middle Aged , Spinal Cord Compression/etiology , Spinal Cord Compression/surgery , Spinal Cord Stimulation/adverse effects , Spinal Cord Stimulation/methods , Spinal Stenosis/complications , Spinal Stenosis/surgery
3.
Brain Spine ; 2: 100858, 2022.
Article in English | MEDLINE | ID: mdl-36248110

ABSTRACT

Introduction: A precise knowledge of the possible Adverse Events (AEs) related to spinal surgical procedures is crucial in clinical practice. Research Question: Purposes of this study are: to determine the prevalence and severity of perioperative AEs associated with pediatric and adult spine surgery in a high volume center; to estimate the impact of perioperative AEs on length of hospital stay (LOS). Material and Methods: This is a prospective, observational, monocenter study, including 346 consecutive patients (294 adults and 52 pediatrics). The SAVES-V2 questionnaire was used to record AEs. The form was updated by the medical staff every time an adverse event was recorded during hospitalization. Results: 21,2% of pediatric patients and 20,7% of adults had at least 1 perioperative AEs. In adults, dural tear (3.1%) and neuropathic pain (4,8%), were the most frequent intraoperative and postoperative AE, respectively. In pediatric patients, neurologic deterioration was the most frequent postoperative AE. A diagnosis of deformity (p=0.01), an ASA grade equal or superior to 3 (p=0.023) and the procedure 'Posterior Spinal Fusion' (p=0.001) were associated with a higher frequency of AEs. AEs required prolonged LOS in 40 cases, 7 (70%) pediatric patients and 33 (65%) adults. Discussion and Conclusion: The overall prevalence of AEs is 20.8%, and, although the distribution is almost equal between adult and pediatric patients, their severity is related to age, being higher in pediatric patients. Deformities, deformity correction, revision surgery and AP surgery are the most impactful factors. AEs seriously affect hospitalization, with prolonged LOS (mean 6 days).

4.
Disabil Rehabil ; 44(14): 3422-3429, 2022 07.
Article in English | MEDLINE | ID: mdl-33356640

ABSTRACT

PURPOSE: To evaluate the effect of multimodal exercises integrated with cognitive-behavioural therapy on disability, pain, and quality of life in patients suffering from failed back surgery syndrome (FBSS), and to appraise its extent in the long term. METHODS: By means of a parallel-group superiority-controlled trial, 150 outpatients were randomly assigned to a 10-week individual-based multimodal programme of task-oriented exercises integrated with cognitive-behavioural therapy (experimental group, 75 patients) or individual-based general physiotherapy (control group, 75 patients). Before treatment, 10 weeks later (post-treatment), and 12 months after the end of treatment, the Oswestry Disability Index (primary outcome), the Tampa Scale for Kinesiophobia, the Pain Catastrophising Scale, a pain intensity numerical rating scale and the Short-Form Health Survey were evaluated. Linear mixed model analysis for repeated measures was carried out for each outcome measure. RESULTS: Significant group (p < 0.001), time (p < 0.001), and time-by-group interaction (p < 0.001) effects were found for all outcome measures. Concerning disability, between-group differences (95% confidential interval) in favour of the experimental group of -9 (-10.7; -7.3) after training and of -13.2 (-14.7; -11.7) at follow-up were found. Also, kinesiophobia, catastrophising and pain showed significant between-group differences of 9, 12.5 and 1.7 points, respectively. CONCLUSION: The multimodal intervention proposed was superior to general physiotherapy in reducing disability, kinesiophobia, catastrophising, and enhancing the quality of life of patients with FBSS. The effects were reinforced one year after the programme ended.IMPLICATIONS FOR REHABILITATIONMultimodal exercises integrated with cognitive-behavioural therapy induced significant improvements in disability, pain, kinesiophobia, catastrophising, and quality of life of subjects with Failed Back Surgery Syndrome.A well-integrated rehabilitative team which contributes towards reaching intervention goals is advised.Physiotherapists should adopt task-oriented exercises to promote an earlier return to common activities of disabled patients.Psychologists should explain how to modify useless beliefs and support adequate behaviours, in order to produce constructive attitudes towards perceived disability.


Subject(s)
Cognitive Behavioral Therapy , Failed Back Surgery Syndrome , Exercise Therapy , Follow-Up Studies , Humans , Pain Measurement , Quality of Life , Treatment Outcome
5.
Childs Nerv Syst ; 38(5): 1011-1015, 2022 05.
Article in English | MEDLINE | ID: mdl-34559301

ABSTRACT

INTRODUCTION: We report a case and a literature review of delayed postoperative cervical spinal cord injury after thoraco-lumbar spine surgery. CASE REPORT: A 13-year-old Prader-Willi Syndrome female was treated by a T3-L5 posterior spine fusion for progressive scoliosis. Intraoperative neuromonitoring and immediate postoperative neurological examination were normal. Sixty hours after surgery, she developed a tetraplegia. The immediate MRI and CT scan of the spine were negative. Two days after, a new MRI revealed an ischemic cervical lesion at the level C5-C6. After 1 week, she gradually improved breathing and motility/sensibility at the extremities. After 4 months of intensive neurologic rehabilitation, the patient improved to ASIA grade D and was discharged. At 1-year follow, the neurologic recovery was nearly completed. METHODS: We performed a systematic review of the literature through PubMed and Embase database focused on delayed postoperative cervical spinal cord lesion after a thoraco-lumbar fusion for spinal deformity. RESULTS: Only 14 cases of neurological injuries at levels above the site of surgery have been previously reported and never in Prader Willy Syndrome. All patients were adolescent and 86,7% were females but no specific risk factors were found. CONCLUSIONS: Delayed postoperative neurological deficit far from the surgical site can be considered a specific subgroup of these rare complication that can occur several hours after spine surgery, regardless of intraoperative complication. Despite the rarity of this complication, clinicians should be aware of it. Perioperative optimization of spinal cord perfusion and close neurological examination in first postoperative days may be helpful to quickly recognize and treat this complication.


Subject(s)
Cervical Cord , Scoliosis , Spinal Cord Diseases , Spinal Fusion , Adolescent , Female , Humans , Male , Postoperative Period , Scoliosis/diagnostic imaging , Scoliosis/etiology , Scoliosis/surgery , Spinal Cord Diseases/etiology , Spinal Fusion/adverse effects
7.
Eur Spine J ; 30(1): 208-216, 2021 01.
Article in English | MEDLINE | ID: mdl-32748257

ABSTRACT

PURPOSE: The eXtreme Lateral Interbody Fusion (XLIF) approach has gained increasing importance in the last decade. This multicentric retrospective cohort study aims to assess the incidence of major complications in XLIF procedures performed by experienced surgeons and any relationship between the years of experience in XLIF procedures and the surgeon's rate of severe complications. METHODS: Nine Italian members of the Society of Lateral Access Surgery (SOLAS) have taken part in this study. Each surgeon has declared how many major complications have been observed during his surgical experience and how they were managed. A major complication was defined as an injury that required reoperation, or as a complication, whose sequelae caused functional limitations to the patient after one year postoperatively. Each surgeon was finally asked about his years of experience in spine surgery and XLIF approach. Pearson correlation test was used to evaluate the association between the surgeon's years of experience in XLIF and the rate of major complications; a p-value of last than 0.05 was considered significant. RESULTS: We observed 14 major complications in 1813 XLIF procedures, performed in 1526 patients. The major complications rate was 0.7722%. Ten complications out of fourteen needed a second surgery. Neither cardiac nor respiratory nor renal complications were observed. No significant correlation was found between the surgeon's years of experience in the XLIF procedure and the number of major complications observed. CONCLUSION: XLIF revealed a safe and reliable surgical procedure, with a very low rate of major complications, when performed by an expert spine surgeon.


Subject(s)
Spinal Fusion , Humans , Italy/epidemiology , Lumbar Vertebrae/surgery , Reoperation , Retrospective Studies , Spinal Fusion/adverse effects , Spine , Treatment Outcome
8.
J Orthop Res ; 39(10): 2209-2216, 2021 Oct.
Article in English | MEDLINE | ID: mdl-33331674

ABSTRACT

Few studies evaluated bacterial colonization of spinal implants from a "topographic" point of view. This lack of knowledge could hinder the development of more effective strategies in the prevention and treatment of postoperative spinal infections. The aim of this in vitro study was the analysis of the adhesion pattern of sessile cells on conventional spinal implants, to identify "hot spots" on implants where bacterial adhesion could be favored. Clinically relevant Staphylococcus aureus, Staphylococcus epidermidis, and Pseudomonas aeruginosa isolates were grown on commercially available end product spinal implants. To identify sessile cells attached to implant surfaces, confocal laser scan microscopy was used. Different areas from the spinal instrumentations (both Ti and CoCr) were selected for biofilm quantification. Bacterial biofilm was markedly increased in the cut of the rods, both Ti and CoCr, as the uneven surface deriving from the cut might foster cell adhesion. Though not statistically significant, a difference was observed between the rod and the area of the notch, possibly as a consequence of the smoothening effect deriving from the bending of the rod. Finally, the amount of biofilm produced on cobalt-chromium surfaces was always more significant than that formed on titanium surfaces. This study highlights how bacterial adhesion through biofilm formation is favored on the surfaces of higher irregularity and that staphylococci are able to increase sessile biomass on CoCr surfaces. These preliminary results show how surface modifications on the implants may play a key role in bacterial adhesion, opening an exciting field for future research.


Subject(s)
Bacterial Adhesion , Staphylococcus epidermidis , Biofilms , Prostheses and Implants , Staphylococcus aureus , Surface Properties , Titanium
9.
Spine J ; 19(11): 1840-1849, 2019 11.
Article in English | MEDLINE | ID: mdl-31377476

ABSTRACT

BACKGROUND CONTEXT: Sagittal plane alignment is of crucial importance for the treatment of spinal deformities. When planning corrective strategies, spine surgeons need to refer to normative parameters' ranges which characterize the alignment in the asymptomatic population. Changes are known to occur with age. For the Caucasian population, the reference ranges are extensively documented for the young and middle-aged adults. In contrast, only a few studies have evaluated individuals in advanced age (>60 years) and in groups of limited numbers of subjects (less than 50). PURPOSE: To describe the normative parameter ranges of sagittal spine alignment in a large population of asymptomatic elderly subjects. STUDY DESIGN/SETTING: Monocentric, prospective, cross-sectional study. PATIENT SAMPLE: One hundred sixty asymptomatic elderly volunteers (age>60 years, Caucasian heritage), consecutively enrolled. OUTCOME MEASURES: Sagittal parameters of spine and pelvis: thoracic kyphosis (TK); lumbar lordosis (LL); sacral slope (SS); pelvic incidence (PI); pelvic tilt (PT); sagittal vertical axis (SVA); T1 pelvic angle (TPA); mismatch between PI and LL (PI-LL); Roussouly classification of the lumbopelvic profile. METHODS: Each subject underwent one radiographic scan, performed in standing position with EOS low-dose system (EOS Imaging, Paris, France). The radiographic images were processed with sterEOS software allowing identification of the anatomical parameters and the presence of scoliosis. SVA, TPA, and the lumbopelvic profile were manually measured in the lateral images. The results were compared to previous studies describing younger adult populations. The study was supported by the Italian Ministry of Health in the amount of $15,000. The authors declare that there are no conflicts of interests. RESULTS: Overall, the average values of the spinopelvic parameters were the followings: TK, 55±14°; LL, 57±12°; PI, 55±11°; SS, 38±10°; PT, 16±7°. The average PI-LL, SVA, and TPA was -3±11°, 25±32 mm, and 14.6±7.4°, respectively. TK, TPA, and SVA were found increasing with age. As for classification of the lumbopelvic profile, 16% of subjects were excluded because they were considered not to belong to any of the Roussouly types. In the classified subjects, the distribution was similar to that of younger adults. Asymptomatic scoliosis (average Cobb angle, 22±7°) was identified in 27% of individuals. CONCLUSIONS: The ranges of values pointed out differences compared to younger adults and represent an important resource for spine surgeons in planning the surgical correction of spinal deformities. The characteristic changes occurring with age, as well as the observed presence of mild or moderate asymptomatic scoliosis, should be carefully taken into account. The classification of the lumbopelvic profile based on the Roussouly scheme revealed some limitations, although similar frequencies were identified compared to younger adults.


Subject(s)
Aged/physiology , Spine/diagnostic imaging , Spine/physiology , Standing Position , Aged, 80 and over , Asymptomatic Diseases , Cross-Sectional Studies , Female , France , Humans , Kyphosis/diagnostic imaging , Kyphosis/physiopathology , Lordosis/diagnostic imaging , Lordosis/physiopathology , Male , Middle Aged , Pelvis/diagnostic imaging , Pelvis/physiology , Prospective Studies , Radiography , Reference Values , Sacrum/diagnostic imaging , Sacrum/physiology , Scoliosis/diagnostic imaging , Scoliosis/physiopathology , Spine/physiopathology , Whole Body Imaging
10.
Eur Spine J ; 27(9): 2272-2284, 2018 09.
Article in English | MEDLINE | ID: mdl-29497853

ABSTRACT

PURPOSE: To review the incidence of perioperative and late complications of surgery for spinal deformity (ASD). METHODS: Review of the literature. We reviewed recent literature in English to investigate the incidence of complications in ASD surgery in the perioperative (≤ 3 months post-operative) and late (> 3 months post-operative) periods. Randomized-controlled trials, non-randomized trials, cohort studies, case-control studies, and case series published in 2005 or later were included. We divided articles according to surgical technique: open procedures (OP), minimally invasive surgery (MIS), and hybrid procedures (HP). Complications were recorded, grouped by surgical technique, and then classified according to a proposed Grading of Incidence of Complications (IOC). RESULTS: Ninety-six publications reporting on 12,168 patients were included; 68 were level IV of evidence studies, 24 were level III, and 4 level II. Perioperative IOC was 26.5% in OP, 36.4% in HP, and 24.2% in MIS. Late IOC was 11.1% in OP, 15.4% in HP, and 14.0% in MIS. IOC was significantly higher for hybrid procedures compared to both open and MIS procedures. CONCLUSIONS: Reported complications of surgery for ASD in the recent literature are frequent (24-36% perioperative plus 11-15% late). Open procedures were the most extensively reported in the literature. Complication rates are similar for OP and MIS. HP presented higher IOC likely due to the combination of OP and MIS respective complications. Small number of studies and heterogeneity in reporting could result in risk of bias in these results. Large-scale registry-based studies can fill this gap in the future. These slides can be retrieved under Electronic Supplementary Material.


Subject(s)
Postoperative Complications/epidemiology , Spinal Curvatures/surgery , Spinal Fusion , Adult , Humans , Incidence , Spinal Fusion/adverse effects , Spinal Fusion/methods , Spinal Fusion/statistics & numerical data , Treatment Outcome
11.
Eur Spine J ; 26(Suppl 4): 450-456, 2017 10.
Article in English | MEDLINE | ID: mdl-28456854

ABSTRACT

STUDY DESIGN: The investigation was based on finite-element simulations. OBJECTIVE: Pedicle subtraction osteotomy (PSO) is an effective but technical demanding surgical technique, associated with a high risk of rod failure. The present study aims at investigating the role of the anterior support in combination with PSO, with a numerical comparative analysis. METHODS: An osteotomy was simulated at the L3 level of a lumbosacral spine. An implantation of various combinations of devices for the anterior (1 or 2 cages of different material) and posterior stabilization (1 or 2 rods) was then performed. ROM, loads, and stresses acting on the rods were calculated. RESULTS: A 4-8% reduction of the ROM was obtained introducing one or two cages in the instrumented model. However, the anterior support had only a minor influence on the ROM. The load on the posterior instrumentation decreased up to 8% using one cage and about 15% with two anterior devices. A 20-30% reduction of the stresses on the rods was calculated inserting one cage and up to 50% using two cages. Following the introduction of the anterior support, the greatest stress reduction was observed in the model having two cages and spinal fixators with two rods. CONCLUSIONS: The use of cages is crucial to ensure anterior support and decrease loads and stresses on the posterior instrumentation.


Subject(s)
Computer Simulation , Lumbar Vertebrae/surgery , Osteotomy/methods , Spinal Fusion/methods , Biomechanical Phenomena , Finite Element Analysis , Humans
12.
Magn Reson Imaging Clin N Am ; 24(3): 515-22, 2016 Aug.
Article in English | MEDLINE | ID: mdl-27417398

ABSTRACT

Advances in MR imaging technologies, as well as the widening of their availability, boosted their use in the diagnosis of spinal disorders and in the preoperative planning of spine surgeries. However, the most consolidated approach to the assessment of adult patients with spinal disorders is based on the analysis of full standing radiographs (posteroanterior and laterolateral views). In this article, the radiographic spinal and pelvic parameters, which have relevance in the clinical management of adults with spinal disorders, are summarized.


Subject(s)
Magnetic Resonance Imaging , Radiography , Spinal Diseases/diagnostic imaging , Spine/abnormalities , Spine/diagnostic imaging , Humans , Spine/anatomy & histology
13.
Eur Spine J ; 25(10): 3120-3129, 2016 10.
Article in English | MEDLINE | ID: mdl-27015689

ABSTRACT

PURPOSE: To evaluate the effects of motor and cognitive rehabilitation on disability in adults with idiopathic scoliosis at lower risk of progression. METHODS: 130 adults with idiopathic scoliosis (main curve <35°) were randomly assigned to a 20-week rehabilitation programme consisting of active self-correction, task-oriented exercises and cognitive-behavioural therapy (experimental group, 65 subjects, mean age of 51.6, females 48) or general physiotherapy consisting of active and passive mobilizations, stretching, and strengthening exercises of the spinal muscles (control group, 65 subjects, mean age of 51.7, females 46). Before, at the end, and 12 months after treatment, each participant completed the Oswestry disability index (ODI) (primary outcome), the Tampa scale for kinesiophobia, the pain catastrophizing scale, a pain numerical rating scale, and the Scoliosis Research Society-22 Patient Questionnaire. Radiological (Cobb angle) and clinical deformity (angle of trunk rotation) changes were also investigated. A linear mixed model for repeated measures was used for each outcome. RESULTS: Significant effects of time, group, and time by group interaction were found for all outcome measures (P < 0.001). After training, the primary outcome showed a clinically significant between-group change (12 % points), which was preserved at follow-up. At follow-up, the radiological deformities showed a significant, although not clinically meaningful, between-group difference of 4° in favour of the experimental group. CONCLUSION: The experimental programme was superior to general physiotherapy in reducing disability of adults with idiopathic scoliosis. Motor and cognitive rehabilitation also led to improvements in dysfunctional thoughts, pain, and quality of life. Changes were maintained for at least 1 year.


Subject(s)
Cognitive Behavioral Therapy/methods , Disabled Persons/rehabilitation , Exercise Therapy/methods , Physical Therapy Modalities , Scoliosis/rehabilitation , Adult , Aged , Female , Humans , Male , Middle Aged , Outcome Assessment, Health Care , Pain Measurement , Patient Satisfaction , Quality of Life
15.
Eur Spine J ; 23(1): 87-95, 2014 Jan.
Article in English | MEDLINE | ID: mdl-23836299

ABSTRACT

PURPOSE: To evaluate the effect of a rehabilitation programme including the management of catastrophising and kinesiophobia on disability, dysfunctional thoughts, pain, and the quality of life in patients after lumbar fusion for degenerative spondylolisthesis and/or lumbar spinal stenosis. METHODS: This was a parallel-group, randomised, superiority-controlled study in which 130 patients were randomly assigned to a programme consisting of exercises and cognitive-behavioural therapy (experimental group, 65 subjects) or exercises alone (control group, 65 subjects). Before treatment (T1), 4 weeks later (post-treatment analysis, T2) and 12 months after the end of treatment (follow-up, T3), all the patients completed a booklet containing the Oswestry Disability Index (ODI, primary outcome), the Tampa Scale for Kinesiophobia, the Pain Catastrophising Scale, a pain Numerical Rating Scale, and the Short-Form Health Survey. A linear mixed model for repeated measures was used for each outcome measure. RESULTS: The ODI linear mixed model revealed significant main effects of group (F(1,122.8) = 95.78, p < 0.001) and time (F(2,120.1) = 432.02, p < 0.001) in favour of the experimental group. There was a significant group × time interaction effect (F(2,120.1) = 20.37, p < 0.001). The analyses of all of the secondary outcome measures revealed a significant effect of time, group and interaction in favour of the experimental group. CONCLUSION: The rehabilitation programme, including the management of catastrophising and kinesiophobia, was superior to the exercise programme in reducing disability, dysfunctional thoughts, and pain, and enhancing the quality of life of patients after lumbar fusion for degenerative spondylolisthesis and/or LSS. The effects lasted for at least 1 year after the intervention ended.


Subject(s)
Catastrophization/therapy , Cognitive Behavioral Therapy/methods , Exercise Therapy/methods , Phobic Disorders/therapy , Spinal Stenosis/rehabilitation , Spondylolisthesis/rehabilitation , Adult , Disabled Persons , Disease Management , Female , Humans , Lumbar Vertebrae/surgery , Male , Middle Aged , Movement/physiology , Outcome Assessment, Health Care , Pain Measurement , Quality of Life , Spinal Stenosis/psychology , Spinal Stenosis/surgery , Spondylolisthesis/psychology , Spondylolisthesis/surgery , Treatment Outcome
17.
Int J Biochem Cell Biol ; 44(6): 1019-30, 2012 Jun.
Article in English | MEDLINE | ID: mdl-22481027

ABSTRACT

Intragenic polymorphisms in the vitamin D receptor gene are linked to disc degeneration features, suggesting that alterations in the vitamer-mediated signalling could be involved in the pathophysiology of the disc and that interaction of disc cells with vitamin D metabolites may be critical for disc health. The vitamer-mediated modulation of disc cells proliferation, metabolic activity, extracellular matrix (ECM) genes expression and proteins production was investigated. It was stated that disc cells express vitamin D receptor and are very sensitive to metabolic stimuli. In monolayer cultures, 1,25(OH)(2)D(3), but not 24,25(OH)(2)D(3), determined an inhibition of the proliferation and regulated also the ECM genes expression in nucleus pulposus and annulus fibrosus cells. Micromass cultures induced a more physiologic expression pattern of extracellular matrix genes. Cells Treatment with vitamin D metabolites did not result in relevant modifications of glycosaminoglycans production, except for annulus cells, whose production was reduced after 1,25(OH)(2)D(3) treatment. Moreover, a reduced glycosaminoglycans staining in both cell types and a significant reduced aggrecan gene expression in annulus cells treated with 1,25(OH)(2)D(3) were observed. A reduction of collagen I and II staining in annulus cells 1,25(OH)(2)D(3) treated, in accordance with a downregulation of collagen genes expression, was also registered. Finally, the vitamin D receptor gene expression did not show significant metabolite-mediated modification in monolayer or micromass cultures. These findings could enhance new insights on the biochemical mechanisms regulated by vitamin D in disc cartilage and possibly involved in the development of physiological/pathological modifications of the disc.


Subject(s)
Intervertebral Disc/metabolism , Vitamin D/metabolism , Adult , Base Sequence , Cell Proliferation , DNA Primers , Female , Humans , Immunohistochemistry , Male , Middle Aged , Real-Time Polymerase Chain Reaction , Receptors, Calcitriol/genetics
18.
Med Eng Phys ; 33(4): 490-6, 2011 May.
Article in English | MEDLINE | ID: mdl-21177135

ABSTRACT

The surgical devices for the treatment of degenerative disc disease are based on different concepts (rods for spine fusion, ROM-restricting or load-bearing devices for dynamic stabilization). In the present work, the effects of some stabilization systems on the biomechanics of the lumbar spine were investigated by means of a finite element model of the L2-L5 spine segment. Pedicular screws and stabilization devices were added at L4-L5. Different rods were considered: stainless steel, titanium, PEEK and the composite ostaPek. Two pedicular devices aimed at motion preservation were also considered: the FlexPLUS and the DSS. All models were loaded by using the hybrid protocol in flexion, extension, lateral bending and axial rotation. The spine biomechanics after implantation resulted significantly sensitive to the design and the materials of the device. The impact of all rods in reducing the ROM was found to be critical (>70% in flexion and extension). The dynamic devices were able to preserve the motion of the segment, but with different performances (ROM reduction from 30% (DSS) to 50% (FlexPLUS)). The shared load was more sensitive to the elastic modulus of the device material than the calculated ROMs (from 7% (PEEK) to 48% (stainless steel)). Regarding devices aimed at motion preservation, the authors suggest to distinguish "flexible" devices, which are able to preserve only a minor fraction (e.g. at most 50%) of the physiological ROM, from "dynamic" devices, which induce a smaller ROM restriction. However, the optimal characteristics of a stabilization device for the treatment of degenerative disc disease still need to be determined by means of basic science and clinical studies.


Subject(s)
Finite Element Analysis , Lumbar Vertebrae/physiology , Lumbar Vertebrae/surgery , Mechanical Phenomena , Biomechanical Phenomena , Intervertebral Disc Degeneration/physiopathology , Intervertebral Disc Degeneration/surgery , Movement , Rotation , Stress, Mechanical , Weight-Bearing
20.
J Neurosurg Spine ; 13(5): 568-75, 2010 Nov.
Article in English | MEDLINE | ID: mdl-21039145

ABSTRACT

OBJECT: Interspinous devices are widely used for the treatment of lumbar stenosis. The DIAM spinal stabilization system (Medtronic, Ltd.) is an interspinous implant made of silicone and secured in place with 2 laces. The device can be implanted via posterior access with the sacrifice of the supraspinous ligament (SSL) or via lateral access with preservation of the ligament. The aim of the present work was to evaluate the role of the laces, the SSL, and the device size and positioning to determine the device's ability in reducing segmental lordosis and in stabilizing motion. METHODS: Biomechanical tests were performed in flexion and extension on 8 porcine spines implanted with the DIAM either with or without the laces and the SSL. A finite element model of the human L4-5 spine segments was also created and used to test 2 sizes of the device implanted in 2 different positions in the anteroposterior direction. RESULTS: Implantation of the DIAM induced a shift toward kyphosis in the neutral position. Laces, the SSL, and device size and placement had a significant influence on the neutral position, the stiffness of the implanted spine, and the positions of the instantaneous centers of rotation. CONCLUSIONS: The shift of the neutral position toward kyphosis may be beneficial in reducing symptoms of spinal stenosis such as radicular pain, sensation disturbance, and loss of strength in the legs. The authors recommend preservation of the SSL and the use of the fixation laces, given their relevant mechanical role. Choosing the proper device size and placement should be achieved by using a correct surgical technique.


Subject(s)
Joint Instability/surgery , Lordosis/surgery , Prostheses and Implants , Spinal Diseases/surgery , Animals , Biomechanical Phenomena , Equipment Design , Finite Element Analysis , Humans , In Vitro Techniques , Kyphosis/etiology , Lumbar Vertebrae/surgery , Models, Anatomic , Prostheses and Implants/adverse effects , Range of Motion, Articular , Swine
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