Academic literature on the topic 'Spondylolyse'

Le rachis est une structure ostéo-disco-ligamentaire complexe jouant un rôle majeur dans la stabilité et la mobilité du corps humain. Dans certaines conditions, des blessures traumatiques ou de fatigue peuvent survenir. Chaque année, plus de 700000 nouveaux traumas rachidiens sont comptabilisés au niveau mondial. Les blessures de fatigue, résultant d’une sur-sollicitation des structures vertébrales, sont fréquentes dans le domaine sportif. La spondylolyse est la blessure la plus commune parmi les blessures de fatigue dues au sport, notamment chez les adolescents. Cette thèse vise à améliorer la compréhension des mécanismes de blessures du rachis lombaire dans des conditions traumatiques et sportives en tenant compte des facteurs intrinsèques (posture, propriétés mécaniques des ligaments) et extrinsèques (conditions de chargement). Le volet expérimental décrit la caractérisation des ligaments du rachis thoracique et lombaire humain en traction uni-axiale dynamique. Le volet numérique porte sur l’analyse par éléments finis des pathomécanismes du rachis lombaire en conditions traumatiques, d’une part, et pour l’étude des risques de spondylolyse dans le domaine sportif d’autre part. Cette thèse a été réalisée en cotutelle entre Polytechnique Montréal et le Laboratoire de Biomécanique Appliquée (UMRT21 Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux/ Aix-Marseille Université) et s’inscrit dans les travaux de recherche du Laboratoire international – Imagerie et biomécanique du rachis (iLab-Spine) et de la Chaire de recherche industrielle CRSNG/Medtronic en biomécanique de la colonne vertébrale
The spine is an osteo-disco-ligamentous structure playing a major role in the human body’s stability and mobility. In some conditions, traumatic or stress injuries may happen. Each year, more than 700,000 new traumatic injuries are diagnosed worldwide. Stress injuries result from overuse of spinal structures because of repetitive movements and sport practice is a common cause. The spondylolysis is the most common stress injuries due to sport activities, particularly in adolescents. The objective of this thesis was to improve the understanding of the lumbar injury mechanisms in traumatic and sport-related conditions taking into account intrinsic (posture, ligament mechanical properties) and extrinsic factors (loading conditions). The experimental part deals with the lumbar and thoracic ligament characterization under uni-axial dynamic tensile tests. The numerical part was performed to assess the pathomechanisms of the lumbar spine in traumatic conditions and related to the risk of spondylolysis in sport-related conditions. This project was done as a joint program between Ecole Polytechnique de Montreal and the Laboratoire de biomécanique appliquée (UMRT21 Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux/ Aix-Marseille Université) and was a part of the research work of the iLab-Spine (International Laboratory - Spine Imaging and Biomechanics) and the Industrial Research Chair program CRSNG/Medtronic on the spinal biomechanics

Study 1: Study design: A non –randomised continuous retrospective cross sectional and observational study Objective 1) To evaluate the results of nonoperative treatment of symptomatic lumbar pars stress injuries or spondylolysis in sporting as well as non sporting individuals 2) To determine the factors responsible for non-operative method of managing symptomatic lumbar spondylolysis in young population 3) To evaluate the outcome in different types of sports 4) To establish the role of compulsory non-operative treatment for symptomatic lumbar spondylolysis in sporting individuals Summary of Background Data The treatment and management of symptomatic spondylolysis in sporting populations is mainly based on observation rather than experimental study. Conservative treatment in the form of bracing and avoidance of sports for at least three to six months has been recommended. Excellent or good results following bracing and physical therapy have been observed in 80% patients. Criteria for return to sport are dominated by symptom led decisions. Methods The research was carried out as a qualitative, descriptive and analytic study with a non-randomised cohort of patients investigated for spondylolysis in a single centre. A total number of 123 patients treated conservatively following confirmation by imaging studies (SPECT,CT or MRI scans) as having stress fractures of the lumbar pars interarticularis (PI) ranging in age from 8 to 35 years have been selected for the study. All patients attending the Back pain clinic has to follow a protocol of filling up the VAS, ODI and SF-36 questionnaires as a part of their assessment. At the time of the study these questionnaires along with the Back Pain & Sports Questionnaire (BPSQ) were sent to all but only 123 patients responded who were included in the study 1. The background data contains gender, age, date of onset of symptoms with current limitation in sport, pain in flexion or extension, type of sport, level of sport and length of treatment. The data also contains each subject with level, number, laterality and distribution of lumbar spondylolysis, investigations, outcome with VAS, ODI, SF-36 and Back pain and sports questionnaire (BPSQ) and return to sports. We classified the individual sports into seven types depending on the major movements of the body. Descriptive and analytical statistics was performed along with correlation testing between the outcome measures and predictive factors. Results The mean age of onset of back pain was 21.7 years (range 8-35 years). Most patients were between the ages of 15&19 years (43) followed by 20&24 years (32). The Male: Female ratio was 74:49. There were 98/123 (76.9%) sporting individuals. 35/98 (35%) were professional players, 29/98 (29.5%) were semi professional and 34/98 (34.6%) were amateur sportsmen and women. Cricket (22) followed by Football (22) were the most common type of sports played. Trunk twisting movement was the common denominator in most of the patients with pars defect. The cricketers (13) with unilateral pars defect had more commonly left sided pars defect than the right (10 left vs 3 right). Right sided pars defect was more commonly observed in soccer players (7:1). Most incomplete fractures were observed at L4 in the cricketers. The non sporting group had consulted with a delay of more than six months since the onset of pain. 60% pars lesion was observed at L5 followed by L4 (11.3%), L3 (9.7%) and L2 (2.4%). At L5 most were bilateral lesions (81%). Spina bifida was recorded in 16% patients. The mean pre and post treatment VAS score was 4.5 and 0.65 respectively (SD- 0.8,p<0.01). The mean pre and post treatment ODI was 35.5 (SD-7.8) and 6.9 (SD- 7.6) respectively (p<0.01). In the SF-36 scores, the mean score for the physical component of health improved from 34.9 (SD – 5.3) to 49.3 (SD -6.6) (p< 0.001). The mean score for the mental component of health improved from 40.2 (SD -5.2) to 52.0 (SD-6.0) (p<0.001). The mean BPSQ score was 52.5 (range 0-90). The mean pretreatment and post-treatment VAS and ODI scores were slightly better in males as compared to females. In the unilateral group, 28/36 (77%) patients had complete relief of pain by a mean time of 4.2 months (range 3-7 months). In the bilateral group, 47/59 (79%) patients had complete pain relief at a mean time of 6.5 months (3-12 months). In the unilateral pars defect group, 32/36 sporting individuals returned to active sports. In the bilateral pars defect group, 49/59 sporting individuals returned to active sports. There was significant difference between the sporting and the non-sporting group in their age (mean 20.7 vs 25.4 years, p <0.001). There was significant difference between the two groups in all pre and post treatment outcome scores. The pre treatment VAS score had most significant correlation with post treatment ODI ( =0.634, p <0.01) and post treatment VAS scores ( =0.626, p<0.01). Conclusion A treatment protocol of rest for 4-6 weeks followed by the functional restorative program has excellent or good outcome in 85% sporting individuals with symptomatic pars defect. Male sporting individuals have better outcome than females. Unilateral pars lesions have a better outcome than bilateral pars lesions. Bracing may not be required in most patients if the pain subsides on restriction of activity. Full functional recovery to previous level of activity is possible with the help of dynamic spinal stabilization exercises and physical therapy. The individuals involved in trunk twisting sports should be evaluated carefully for muscle imbalance in the lumbar spine and they should have altered techniques of sporting activity without compromising the performance in the rehabilitation phase. Study 2: Study Design: A non –randomised continuous retrospective observational study Objective 1) To identify the most significant determinant of surgical intervention in lumbar pars defect 2) To identify the independent factors that predict a successful outcome following surgery for lumbar pars defect in young sporting individuals 3) Can we establish an outcome predictive model based on these significant factors responsible for a successful outcome? Summary of Background Data Most athletes or young active professional sportsmen or women would like to return to their previous level of sports since they may be earning their livelihood through the sport. Early onset of symptoms and conservative treatment in these patients may lead to a good clinical outcome but it is difficult to predict which group or which individuals will require surgical repair of the defect. Young athletes to have returned to competitive sports after surgery have been reported only in few previous papers. The first cohort from this series was published in 2003. ODI (Oswestry Disability Index) and SF-36 (Short form) scores were used to evaluate the final outcome for the first time in lumbar spondyloysis for outcome analysis. Methods A total number of 55 patients treated operatively following confirmation by imaging studies (SPECT,CT or MRI scans) as having stress fractures of the lumbar pars interarticularis (PI) ranging in age from 8 to 35 years have been selected for the study. All patients attending the Back pain clinic has to follow a protocol of filling up the VAS, ODI and SF-36 questionnaires as a part of their assessment. At the time of the study these questionnaires along with the Back Pain & Sports Questionnaire (BPSQ) were sent to all but only 50/55 patients responded. The background data contains gender, age, date of onset of symptoms with current limitation in sport, pain in flexion or extension, type of sport, level of sport and length of treatment. The data also contains each subject with level, number, laterality and distribution of lumbar spondylolysis, investigations, outcome with VAS, ODI, SF-36 and Back pain & sports questionnaire (BPSQ) and return to sports.

Bakgrund: Smärta i ländryggen är ett vanligt förekommande problem i samhället. Diagnoserna Spondylolys och Spondylolisthes är tillstånd som kan generera smärta och nedsatt funktion i ryggen hos de som drabbas. Det saknas idag tydliga riktlinjer vad gäller fysioterapeutiska behandlingsåtgärder för denna patientgrupp. Syfte: Var att kartlägga de aktuella konservativa behandlingsmetoder inom det fysioterapeutiska fältet som idag används för att rehabilitera patienter med spondylos och spondylolisthes. Metod: En systematisk litteraturöversikt med randomiserade kontrollerade studier och fallstudier. Sökningar har genomförts i databaserna CINAHL och PUBMED. Resultat: Av totalt 9 studier var 5 stycken randomiserade kontrollerande studier och resterande 4 studier var fallstudier. Totalt antal deltagare var 2071. Diagnosen spondylolys var enbart representerat hos 1 av artiklarna och diagnosen spondylolisthes var representerat i 8 av artiklarna. Behandlingsmetoder för Spondylolys bestod av vila från aktivitet i 2–3 månader, behandling med korsett och individanpassad fysioterapi. Behandlingsalternativen för spondylolisthes var individanpassad fysioterapi i form av träning kombinerat med en kognitiv behandlingsstrategi. Styrketräning för ryggen och specifika stabilitetsövningar samt kontrollövningar för bålen. Träning i kombination med mobilisering av ryggen. Individanpassad fysioterapi bestående av hemövningar, råd och utbildning kring aktivitet samt receptfria läkemedel. Stabilitetsövningar för ländryggen i kombination med värmebehandling och stretching. Konklusion: Det finns en rad olika typer av fysioterapeutiska interventioner som samtliga beskriver en god effekt på de patienter som ingår i de inkluderade studierna men det går inte att dra några slutsatser kring vilken intervention som är mest effektiv i denna systematiska litteraturöversikt då för få artiklar inkluderats som undersöker och jämför samma typ av intervention
Background: Low back pain is a common problem in society. The diagnoses Spondylolysis and Spondylolisthesis are conditions that generate pain and impaired function in the back. There are currently no clear guidelines regarding physiotherapeutic treatment measures for this group. Aim: To map the current conservative treatment methods in the field of physiotherapy that are currently used to rehabilitate patients with spondylosis and spondylolisthesis. Method: A systematic literature review of randomized controlled trials and case studies. Searches have been performed in the databases CINAHL and PUBMED. Results Of a total of 9 studies, 5 were randomized control studies and the remaining 4 studies were case studies. The total number of participants was 2071. Diagnosing spondylolysis was only represented in 1 of the articles and diagnosing spondylolisthesis was represented in 8 of the articles. Treatment methods for Spondylolysis consisted of rest from activity for 2-3 months, handling with a corset and individually tailored physiotherapy. The treatment options for spondylolisthes were individualized physiotherapy in the form of exercise combined with a cognitive treatment strategy. Strength training for the back and specific stability exercises as well as control exercises for the torso. Training in combination with mobilization of the back. Individualized physiotherapy consisting of home exercises, advice and training on activity as well as over-the-counter medicines. Stability exercises for the lumbar spine in combination with heat treatment and stretching. Conclusion: There are a number of different types of physiotherapeutic interventions, all of them can describe a good effect on the patients, but it is not possible to draw any conclusions about which intervention is most effective in this systematic literature review, because the articles that are included donot compare the same type of intervention.

Projeto de Graduação apresentado à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de Licenciada em Fisioterapia
Introdução: a espondilólise lombar (EL) é uma alteração óssea dos pares interarticulares, frequente em jovens desportistas. Objetivo: analisar a presença de EL em crianças e adolescentes desportistas, verificar a precisão dos instrumentos de avaliação, quer clínicos quer imagiológicos, utilizados no diagnóstico da EL, e observar a eficácia dos diversos tipos de tratamento, conservador ou cirúrgico, no retorno a atividade desportiva. Metodologia: foi realizada uma pesquisa computorizada nas bases de dados PubMed, PEDro, Scielo, MedLine e Sciences Direct, e em outras fontes. A análise da qualidade metodológica foi efetuada com os checklists da Strengthening the Reporting of Observational studies in Epidemiology (STROBE). Resultados: foram selecionados 8 artigos, respeitando os critérios de seleção, com 332 atletas adolescentes de ambos os sexos, dos 8 aos 22 anos com EL, praticantes de diversas modalidades desportivas. A presença da EL foi diagnosticada através da análise imagiológica e/ou clinica. E os tratamentos, conservador e cirúrgico, contribuíram para o retorno a atividade desportiva. Conclusão: a EL dos adolescentes é afetada pela repetição dos movimentos extensores e rotadores da coluna lombar. Localiza-se maioritariamente em L5, sendo a RM e o tratamento cirúrgico as escolhas preferenciais na resolução da EL.
Introduction: Lumbar spondylolysis (LS) is a bone alteration of interarticular pairs, frequent in young athletes. Objective: to analyse the presence of LS in sports children and adolescents, to verify the accuracy of evaluation instruments, both clinical and imagiological, used in the diagnosis of LS, and to observe the effectiveness of various types of treatment, conservative or surgical, in returning to sports activity. Methodology: a computerized search was performed on PubMed, PEDro, Scielo, MedLine and Sciences Direct databases, and other sources. Methodological quality analysis was performed with the checklists of the Strengthening the Reporting of Observational studies in Epidemiology (STROBE). Results: 8 articles were selected, respecting the selection criteria, with 332 adolescent athletes of both sexes, from 8 to 22 years old with LS, practicing several sports modalities. The presence of LS was diagnosed through imagiological and/or clinical analysis. And the treatments, both conservative and surgical, contributed to the return to sports activity. Conclusion: adolescents' LS is affected by the repetition of the extensor and rotator movements of the lumbar spine. It is mostly located in L5, with MRI and surgical treatment being the preferred choices in the resolution of LS.
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La spondylolyse et le spondylolisthésis sont une déformité bien connue dans le domaine de l’orthopédie. Par contre, il persiste des confusions et des débats sur différents aspects de cette pathologie incluant l’étiologie, l’histoire naturelle et le traitement. Récemment, deux études ont démontré l’influence significative de la morphologie du sacrum dans le spondylolisthésis par Inoue et al. et Whitesides et al.4,5 Ces trouvailles ont renouvelé l’intérêt dans l’évaluation radiologique de la balance sagittale de cette condition. L’objectif principal de ce travail est d’évaluer l’influence de la forme et l’orientation du sacrum chez les patients atteints de spondylolisthésis. Pour ce faire, nous avons construit une base de données de patients présentant un spondylolisthésis et d’un groupe contrôle. Par la suite les radiographies de ces sujets ont été analysées par un programme d’ordinateur afin de calculer tous les paramètres pertinents. Ce travail nous a tout d’abord permis de déterminer à partir des radiographies de 120 volontaires pédiatriques et plus de 130 patients pédiatriques atteints de la spondylolisthésis, les valeurs moyennes et la variation des paramètres angulaires qui influencent l’équilibre sagittal du rachis. Cette base de données est la première existante dans la population pédiatrique. Ces données seront d’une grande utilité pour le futur lors d’études concernant diverses conditions spinales. Nous avons remarqué une différence significative de la morphologie sacrée chez les sujets présentant le spondylolisthésis. Par ailleurs, l’étude de corrélation nous a également permis d’établir une forte relation entre le sacrum, le bassin et la colonne dans le profil sagittal. Finalement, ce travail a permis une meilleure compréhension globale de la posture sagittale chez les sujets normaux et chez les sujets atteints du spondylolisthésis qui pourra servir pour mieux analyser cette condition et pour ajuster les traitements selon l’analyse.
Developmental spondylolysis and spondylolisthesis is a well known and described sagittal spinal deformity in the literature. However, there is still an ongoing debate on different aspects about this pathology including its etiology, pathophysiology, natural evolution and preferred treatment. Numerous parameters and radiologic measures have been described in order to precisely quantify the abnormal relationship between L5 and S1. So far none of these parameters have been proven reliable to predict the evolution in the spinal deformity. Recently, two interesting studies showed that sacral morphology has a significant influence on spondylolisthesis.4,5 These findings have a direct implication to the evaluation and treatment of spondylolisthesis. This also renews our scientific interest in the sagittal morphology in this condition. The principal objective of this work is to evaluate the influence of the sacral form and orientation in patients with spondylolisthesis. First of all, we constructed a large database of all patients with spondylolisthesis with a comparable control group. After the radiographs are analyzed by computer to calculate all possible sagittal parameters described in the current literature. This project has first of all allowed us to establish an ongoing database of all patients with spondylolysis and spondylolisthesis. So far this database is the largest in the literature and consists of more than 120 subjects. This database allows us to analyze retrospectively and prospectively on the influence of sacropelvic sagittal morphology in subjects with spondylolisthesis.

De multiples études ont rapporté une prévalence augmentée de spondylolyse et de spondylolisthésis chez certains groupes d’athlètes, en particulier les gymnastes, pouvant atteindre jusqu’à 40 à 50%. À cela s’ajoute le fait que plusieurs études récentes ont démontré une association entre le spondylolisthésis et une morphologie et orientation sacro-pelviennes déviante de la normale. La morphologie et l’orientation sacro-pelviennes chez les gymnastes ainsi que leur relation avec le spondylolisthésis n’ont jamais été analysées. L’objectif de cette étude était donc d’évaluer la prévalence du spondylolithésis au sein d’une cohorte de gymnastes ainsi que les caractéristiques démographiques et paramètres de morphologie et orientation sacro-pelviennes associés. Afin d’atteindre cet objectif, une évaluation des caractéristiques démographiques et des paramètres radiologiques d’une cohorte de 92 jeunes gymnastes a été menée. Les deux études présentées ont démontré une prévalence de spondylolisthésis chez les jeunes gymnastes de 6.5%, similaire à celle retrouvée dans la population générale. Le nombre d’heures d’entraînement hebdomadaire a été le seul facteur statistiquement différents entre les gymnastes avec et ceux sans spondylolisthésis. Nos résultats ont aussi démontré que les gymnastes atteints d’un spondylolisthésis présentent une morphologie et une orientation sacro-pelviennes sagittales différentes, en terme d’incidence pelvienne (p = 0.02) et d’angle de table sacrée (p = 0.036), de celles des gymnastes sans spondylolisthésis. Nos observations supportent donc l’importance du rôle de la morphologie et de l’orientation sacro-pelviennes dans le développement du spondylolisthésis.
Multiple studies have reported an increased prevalence of spondylolysis and spondylolisthesis in certain groups of athletes, including gymnasts, where it can reach as high as 40 to 50%. Numerous studies have shown that sagittal sacro-pelvic morphology and orientation is different in spondylolisthesis. Sacro-pelvic morphology and orientation in gymnasts and their relationship with spondylolisthesis have never been analyzed. The purpose of this study was to evaluate the prevalence of spondylolisthesis in a cohort of gymnasts, as well as the associated demographic characteristics and sacro-pelvic morphology and orientation. In order to achieve our goal, an evaluation of different demographic characteristics and radiological parameters was performed on a cohort of 92 young gymnasts. A 6.5 % prevalence of spondylolisthesis was found. The weekly training schedule was the only statistically significant different demographic characteristic between the two groups, with and without spondylolisthesis. Our results have also shown that sagittal sacro-pelvic morphology and orientation, in terms of pelvic incidence (p = 0.02) and sacral table angle (p = 0.036), is different between gymnasts with and without spondylolisthesis. In conclusion, our observations support the importance of sacro-pelvic morphology and orientation in spondylolisthesis.

碩士
國立交通大學
機械工程系所
96
Spondylolysis occurs in 6% of the general population. Although the etiology of this continuum of conditions is uncertain, genetic predisposition and repetitive trauma have been strongly implicated. Sports in which participants are subjected to repetitive hyperextension across the lumbar spine pose a risk for such injuries. If the lumber spine was imposed to a large force after the occurrence of spondylolysis, the lumber spine might become listhesis and result in spinal instability. A verified finite element model of L1-S1 was used in this research to investigate the biomechanics of spondylolysis in the early stage. The lumbar spine can support a compressive load of physiologic magnitude without collapsing if the load is applied along a follower load path. The numerical simulation will analyze the stability of spondylolysis, forces of the facet joints, shear forces of the endplate and stresses of the disc. This study established lumbar spine model (L1-S1) using the follower load. This study found the loading pathway in the lumbar spine with double pars defect was transmitted form the disc, not from the facet joint. The fracture would be initiated at the endplate in the lumbar spine with pars defect. So the endplate shear stress and the discal stress near the fracture site remarkably increased. The lumber spine might become listhesis.

♦ Spondylolysis is a stress fracture of the vertebral arch. It may lead to vertebral slipping, spondylolisthesis.♦ Spondylolysthesis is commonly lytic, isthmic, or degenerative.♦ Spondylolysis and Spondylolysthesis can affect both children and adults.♦ Most common symptoms are low-back pain and/or radiating pain. True neurologic deficit is rare♦ Treating clinicians should be aware of the processes involved and the common consequences.♦ The majority of symptomatic patients are treated nonoperatively♦ Operation is indicated in rare cases with neurologic deficit and in children or adolescents with a slip of 50 per cent or more♦ Most common complications of surgery are nerve root compromise (especially in connection with slip reduction) and non-union.

This chapter focuses on diagnostic and procedural imaging techniques that are essential for the pain medicine practitioner. Attention is given to most modern imaging modalities, including ultrasonography, fluoroscopy, computed tomography, and magnetic resonance imaging. The chapter includes a review of many advanced pain medicine procedures, such as celiac plexus and stellate ganglion blocks. A discussion regarding the use of imaging to elucidate a problem with an implanted intrathecal drug delivery system is included as well. In addition to the procedure suite, this chapter provides a review of common radiological findings that are critical for the proper diagnosis and management of pain patients, including spondylolysis and Modic changes. Special attention is paid to the use of ultrasound in pain medicine, including diagnostic techniques in musculoskeletal disorders. Many questions contain a review of the significant anatomic considerations with each procedural technique.

Computed tomography (CT)-guidance is typically used when precise needle placement is essential for a successful procedure. It uses ionizing radiation, which could pose risks to the patient and operating staff if proper technique is not used. The performing physician should adhere to all principles of minimizing radiation exposure to the patient and clinicians. Common CT-guided imaging procedures include facet injections, nerve root injections, sacroiliac joint injections, intradiscal procedures, vertebroplasty/sacroplasty, and image-guided ablation of painful bone lesions. Computed tomography is also the imaging modality of choice for aspiration of deep paraspinal soft tissues in addition to disc space or bone biopsy in acute discitis/osteomyelitis. In fluoroscopic-guided knee or shoulder joint injections, CT arthrography is a useful adjunct to better assess anatomy when MRI is contraindicated. When imaging the postoperative spine, CT myelography has some advantages over MRI, and CT is also superior to MRI in assessing par intra-articularis defects or spondylolysis.

Spondylolysis is a defect in the vertebral pars interarticularis. Its cause may be developmental or due to mechanical etiologies such as trauma. Most childhood and adolescent spondylolisthesis (defined as a slip of one vertebrae relative to another) is associated with spondylolysis of the pars interarticularis at the L5–S1 motion segment.

Instability of the lumbar spine is a significant cause of pain and loss of function in the human population. There are a multitude of causes for a reduction or complete loss of stability of the lumbar spine. These causes include but are not limited to degenerative disc disease, spondylolysis, spondylolisthesis, genetic and growth abnormalities, and ligament laxity. Regardless of the cause, instability of the spine often leads to discomfort and loss of function. When conservative options have been exhausted, the surgeon in consultation with the patient may opt for surgical treatment of the unstable segment.

Lumbar spondylolisthesis is an extension of spondylolysis in which breakage of the vertebrae occurs at the pars interarticularis causing the vertebrae to slip forward. Spondylolisthesis is seen in both younger and older populations with most lesions occurring at the L4-L5 or L5-S1 level. Although the forward slippage of the vertebra does not usually exceed 30% of the body’s anterior-posterior width, possible spinal stenosis and nerve impingement may lead to severe pain and other complications. The purpose of this study is to determine the effect of single level and bi-level dynamic stabilization in reducing the spondylolisthesis. We used the finite element model for this purpose since it is not practical to procure specimens with spondylolisthesis for an experimental investigation.