Developmental Spondylolisthesis Research Articles

Evaluation of the effectiveness of the femoro-sacral posterior angle system for measuring spino-pelvic morphology in high-dysplastic developmental spondylolisthesis.

The Femoro-Sacral Posterior Angle (FSPA) system and the pelvic incidence (PI) system are utilized for measuring sagittal spino-pelvic morphology in patients with high-dysplastic developmental spondylolisthesis (HDDS). This study aimed to analyze the accuracy and stability of these two systems. A retrospective analysis was conducted on 45 patients diagnosed with HDDS who underwent surgical treatment at our hospital (HDDS group), along with 45 patients without spondylolisthesis (normal group). Three orthopedic surgeons utilized the FSPA and PI systems to measure various parameters, including FSPA, pelvic angle(PA), sacral incidence (SI), PI, pelvic tilt (PT), and sacral slope (SS), respectively. The intraclass correlation coefficient (ICC) was employed to assess the inter-observer consistency of measurements. There was significant differences in all the parameters between the normal and HDDS groups (p < 0.05), except for SS (p = 0.508). Specifically, SI was lower in HDDS group than in the normal group (23.0 ± 13.4 vs. 38.6 ± 7.1), whereas SS was higher (35.3 ± 15.7 vs. 33.6 ± 7.4). Within HDDS group, there was no statistically significant difference in PI (p = 0.159), SS (p = 0.319), and FSPA (p = 0.173) between pre- and post-surgery measurements. The ICC results indicated superior reliability for the FSPA system (0.842-0.885) compared to the PI system (0.682-0.720) within the HDDS group. Compared with the PI system, the FSPA system demonstrated higher accuracy in evaluating spino-pelvic morphology in HDDS patients. Moreover, it exhibited higher ICC values, indicating higher inter-observer reliability, thus serving as an effective method for assessing spino-pelvic morphology in HDDS patients.

Beyond controversy: Complete reduction of high-grade developmental spondylolisthesis in children"

Beyond controversy: Complete reduction of high-grade developmental spondylolisthesis in children"

High-grade high-dysplastic lumbosacral spondylolisthesis in children treated with complete reduction and single-level circumferential fusion: A prospective case series

IntroductionSurgical treatment of high-grade developmental spondylolisthesis remains controversial with paucity of data reporting complete reduction of the deformity, especially in pediatric patients. Research questionTo assess efficacy and safety of complete reduction and circumferential L5-S1 fusion in children with high-grade high-dysplastic spondylolisthesis. Emphasis was placed on fusion rates, correction of lumbosacral deformity and long-term clinical outcomes by means of patient-reported outcome measures (PROMs). Material and methodsConsecutive series of 18 pediatric patients referred to surgery over an 11-years period. Several radiographic variables and PROMs were collected pre- and post-surgery with minimum follow-up of 2-years. ResultsThe mean age of cohort was 12.9 years with a mean follow-up of 7.8 years. Postoperatively, the mean slip was reduced from 64.4±9.8% to 4.5±5.9% with no loss of correction during follow-up. PROMs significantly improved following the index procedure (p<0.0001). Lumbo-pelvic parameters improved after surgery, including SS, but not PT. Development of adjacent level spondylolisthesis was noted in eight subjects (44%), two of these patients required additional surgery. Posterolateral and anterior fusion was obtained in 100% and 78% of cases, respectively. One patient developed a transient right-sided L5 nerve paresis after surgery that gradually resolved within one year post-surgery. Preoperatively, we recorded three patients with L5 nerve root motor deficit, which resolved completely in two cases and in one patient remained unchanged. Discussion and conclusionComplete reduction can safely be accomplished without an increased risk of nerve root injury. Coupled with single-level circumferential fusion, it provides high fusion rates with satisfactory spino-pelvic alignment.

HIGH GRADE DYSPLASTIC SPONDYLOLISTHESIS IN AN 11 YEAR OLD GIRL CHILD - A CASE REPORT

High-Dysplastic Developmental Spondylolisthesis (HDDS) is an extremely rare situation, comprising of around 5% of the total cases of spondylolisthesis. Clinical Description :- A eleven year-old girl with high-grade dysplastic L5-S1 spondylolisthesis with pain in her lower back along with radicular pain to her lower limbs (right &gt; left). Her X-rays depicted a L5 - S1 anterolisthesis leading to an abnormal kyphosis at lumbo-sacral junction, increased lumbar lordosis and reversal of thoracic kyphosis to lordosis. Management:- A was done along with a cage insertion at the L5 - S1 level. L5 - S1 posterior - spinal fixation Outcome:- Postural correction was achieved immediately post-op and the patient also had relief from the radicular symptoms.

Spondylolisthesis in young patients: postoperative functional outcomes at 22-year mean follow-up.

Previous short- and intermediate-term clinical and radiographic studies demonstrated good results in patients who underwent spine surgery for spondylolisthesis, long-term outcomes are lacking instead. Young patients are often involved in high-demanding and sport activities, therefore good/excellent functional outcomes are very important for their future quality of life. The aim of this study is to assess the long-term functional results in young patients surgically treated for developmental spondylolisthesis. Retrospective evaluation of consecutive patients who underwent lumbar surgery for spondylolisthesis. Inclusion criteria were: spondylolisthesis from grade 1 to spondyloptosis, age at surgery < 25years, follow-up > 15years. The following outcomes were assessed: VAS back, VAS leg, Oswestry disability index (ODI) score, Short Form 12 (SF-12), rate of revision surgery, postoperative recovery and sport activity. 113 patients were enrolled. Mean age at surgery was 19.8years and mean follow-up was 22.1years (16-32). 16 patients (14.2%) needed revision surgery. Functional outcomes at last follow-up were: VAS back = 1.6, VAS leg = 1.4, ODI = 9.2%, SF-12 physical component summary = 50, SF-12 mental component summary = 48.7. Significant differences were assessed in terms of ODI (p = 0.047) and SF-12 PCS (p = 0.015) between group treated with instrumented and non-instrumented techniques. Among the patients who practiced a sport, 87% returned to sport postoperatively (55% at medium-high-intensity level). This study shows good long-term functional outcomes in patients surgically treated for developmental spondylolisthesis. After surgery, there is a low incidence of back pain, the residual disability is mild and almost half of patients recover the same level of sport activity. Instrumented surgical techniques developed over the years seem to be related to high revision rate, but this does not affect long-term functional results.

Cervical sagittal alignment in adolescent high dysplastic developmental spondylolisthesis: how does the cervical spine respond to the reduction of spondylolisthesis?

BackgroundAlthough pelvic and related parameters have been well stated in lumbar developmental spondylolisthesis, cervical sagittal alignment in these patients is poorly studied, especially in high dysplastic developmental spondylolisthesis (HDDS). The purpose of this study is to investigate the sagittal alignment of the cervical spine in HDDS and how the cervical spine responds to reduction of spondylolisthesis.MethodsThirty-three adolescent patients with lumbar developmental spondylolisthesis who received preoperative and postoperative whole-spine x-rays were reviewed. They were divided into the HDDS group (n = 24, 13.0 ± 2.2 years old) and the low dysplastic developmental spondylolisthesis (LDDS) group (n = 9, 15.6 ± 1.9 years old). Spinal and pelvic sagittal parameters, including cervical lordosis (CL), were measured and compared between groups. In the HDDS group, the postoperative parameters were measured and compared with those before surgery.ResultsHDDS group had a higher proportion of cervical kyphosis (70.8% vs. 22.2%, P = 0.019), and there was a significant difference in CL between the two groups (− 8.5° ± 16.1° vs. 10.5° ± 11.8°, P = 0.003). CL was correlated with the Dubousset’s lumbosacral angle (Dub-LSA), pelvic tilt (PT), and thoracic kyphosis (TK). In the HDDS group, CL in patients with a kyphotic cervical spine was significantly improved after reduction of spondylolisthesis (− 16.4° ± 5.9° vs. − 3.6° ± 9.9°, P < 0.001). In the HDDS group, 46% (6/13) of the patients with postoperative Dub-LSA < 90° still had sagittal imbalance (sagittal vertical axis, [SVA] > 5 cm), while no sagittal imbalance was observed in patients with postoperative Dub-LSA > 90° (46% [6/13] vs. 0% [0/11], P = 0.016).ConclusionsHDDS can lead to cervical kyphosis through a series of compensatory mechanisms. Reduction of spondylolisthesis and correction of lumbosacral kyphosis may correct the cervical kyphosis and normalize the overall spinal sagittal profile. Correction of Dub-LSA to above 90° might be used as an objective to better improve the sagittal alignment of the spine.

Prevalence of cervical anterior and posterior spondylolisthesis and its association with degenerative cervical myelopathy in a general population

The purpose of this study was to examine the prevalence of cervical spondylolisthesis according to age and vertebral level and its association with degenerative cervical myelopathy (DCM). This study included 959 participants (319 men and 640 women; mean age, 66.4 years) in the Wakayama Spine Study from 2008 to 2010. The outcome measures were cervical spinal canal (CSC) diameter at C5 level on plain radiographs, the degree of cervical spondylosis using the Kellgren-Lawrence (KL) grade, cervical cord compression on sagittal T2-weighted magnetic resonance imaging, and physical signs related to DCM. The prevalence of cervical anterior and posterior spondylolisthesis was investigated in men and women by age. In addition, logistic regression analysis determined the association between CSC diameter, posterior spondylolisthesis, and clinical DCM after overall adjustment for age, sex, and body mass index. The prevalence of anterior spondylolisthesis was 6.0% in men and 6.3% in women, and that of posterior spondylolisthesis was 13.2% and 8.9%, respectively. In addition, posterior spondylolisthesis prevalence increased with age in both sexes. Logistic regression analysis revealed that developmental canal stenosis (≤13 mm) and cervical posterior spondylolisthesis are independent significant predictive factors for DCM. The prevalence of degenerative cervical posterior spondylolisthesis was increasing with age and more frequent in men than in women. Narrow canal and degenerative cervical posterior spondylolisthesis on X-ray may be useful in predicting or diagnosing DCM.

Clinical, radiological and functional results of transforaminal lumbar interbody fusion in degenerative spondylolisthesis

PurposeTo evaluate the clinical, functional and radiographic outcomes of transforaminal lumbar interbody fusion (TLIF) in degenerative low-grade spondylolisthesis. Materials and MethodsA prospective observational study of 120 consecutive patients (M:F = 24:96) with spondylolisthesis operated with TLIF. Clinical and functional outcome was assessed on Visual analogue Scale (VAS) and Oswestry Disability Index(ODI). The radiological outcome was assessed on sagittal alignment at a specific level, radiologic bony fusion/non-union, intervertebral disc heights and percentage of a slip in relation to the endplate. Clinical and radiological data were collected and analysed. ResultsThe mean age was 50.97 years. The average follow-up was 14.5 months (12 to 18 months). Mean preoperative ODI was 38.73 and postoperatively 21.30. Analysing the radiological fusion with clinical scores, poorer radiological fusion grades correlated with higher VAS scores for pain. 70% of patients achieved >50% reduction in pain and 60% achieved > 30% reduction in ODI. Pelvic incidence (PI), pelvic tilt (PT), sacral slope (SS) and lumbar lordosis (LL) were significantly greater in spondylolisthesis. PI, PT, and SS did not change statistically from the baseline postoperatively but increased LL and Segmental LL (P < 0.001). The results of our study showed a close relation between satisfactory clinical outcome (90%) and solid fusion (80%). There was however a significant number of patients with instrument failure that was found in association with fusion failure. There were no intra-operative complications. ConclusionTLIF is an effective option to achieve circumferential fusion without severe complications. An increased pelvic incidence may be an important factor predisposing to progression in developmental spondylolisthesis. TLIF increases global and segmental LL and provides a satisfactory outcome in symptomatic low-grade degenerative spondylolisthesis.

Comparison of sagittal plane morphology of spine and pelvis in adolescents with L₅S₁ developmental spondylolisthesis and isthmic spondylolisthesis

To compare the sagittal morphological features of the spine and pelvis between L₅S₁ dysplastic spondylolisthesis and isthmus spondylolisthesis in adolescent. Retrospective analysis of 24 cases of adolescent L₅S₁ spondylolisthesis with complete imaging data from May 2002 to December 2016. Those included 8 males and 16 females, aged from 10 to 18 years old with an average of (13.4±2.0) years. Among them, 9 cases were diagnosed as dysplastic spondylolisthesis (dysplasia group) and 15 cases isthmic spondylolisthesis (ischemic group). Radiographic parameters including slippage distance, slippage degree, slippage angle, sagittal vertical axis(SVA), thoracic kyphosis(TK), lumbar lordosis(LL), L₅ incidence(L₅I), pelvic incidence(PI), pelvic tilt(PT), sacral slope(SS), sagittal pelvic thickness(SPT), lumbosacral angle (LSA), sacral table angle (STA) were measured on the spinal lateral X-ray of the standing position. Independent-samples t-test was used in the comparison of each variable between two groups. P<0.05 was considered statistically significant. There were no significant differences in slippage distance, slippage rate, slippage angle between two groups. In dysplasia group, SVA, L₅I, PT, SPT were (37.0±48.4) mm, (57.0±14.8)°, (42.3±15.4)°, (56.1±21.2) mm, respectively, and (-11.0±22.2) mm, (31.7±19.3) °, ( 15.5±10.2)°, (31.4±19.1) mm in ischemic group; and the differences between the two groups were significant(P<0.05). In ischemic group, SS, LSA, STA were (44.1±12.6)°, (103.9±21.7)°, (92.7±9.9)°, respectively, and (25.9±20.2) °, (75.4±16.4) °, (75.4±9.7) ° in dysplasia group; and the differences between the two groups were significant(P<0.05). There was no significant difference in TK, LL between two groups(P>0.05). Significant different from isthmic spondylolisthesis, adolescents with dysplastic spondylolisthesis present a different spino-pelvic sagittal alignment, characterized with trunk forward leaning and pelvic retroversion. In case of sagittal imbalance, early surgical intervention is required to restore a balanced spino-pelvic alignment.

Surgical Treatment of Developmental Spondylolisthesis: Contemporary Series With a Two-Surgeon Team

Study DesignRetrospective case series. ObjectivesTo report operative outcomes of contemporary surgical treatment of spondylolisthesis in the pediatric population. Summary of Background DataSurgical treatment of developmental spondylolisthesis is controversial, with limited data on complication and reoperation rates. MethodsA retrospective study followed pediatric patients with either L5–S1 high-grade spondylolisthesis (HGS) or L5–S1 symptomatic low-grade spondylolisthesis (LGS) for a minimum of two years. All patients underwent a contemporary, single-stage decompression, partial reduction, and posterior instrumented fusion (DRPF) or in situ stabilization by a combined orthopedic and neurosurgeon team at a single institution during 2005–2015. Clinical examination and radiographic data were collected preoperatively and at discharge, 1 year, 2 years, and terminal visit (defined as the last follow-up at >2 years). ResultsThirty-four patients (79% HGS), mean (±standard deviation) age at surgery 13.5 (±3.3) years, were followed for 4.8 (±2.3) years. The patients who underwent DRPF (n = 26) had mean lumbosacral angle increase from 79.8° (±20.8) to 92.5° (±16.1) (p < .001) and mean listhesis reduce from 63.2% (±21.9) to 26.0% (±20.1) (p < .001). Preoperatively, 18 (53%) had neurologic symptoms. At one- and two-year follow-up, new or residual neurologic symptoms were present in four patients (12%) (p < .001). Postoperative symptoms were not significantly related to amount of reduction. Sixteen (47%) underwent reoperation at an average of 24.8 months, 10 for planned prominent instrumentation removal, and 6 for true complications. ConclusionsSurgical reduction and decompression of spondylolisthesis in the pediatric population restores spinopelvic alignment. We found no evidence that a greater amount of reduction was associated with a higher incidence of postoperative complications. However, patients should be advised that prominent instrumentation may require future removal. Although previous reports suggest complication rates and permanent neurologic sequelae in up to 20% after operative treatment of spondylolisthesis, our results suggest that a contemporary approach with a two-surgeon team may provide improved results. Level of EvidenceLevel IV.

Posterior reduction and monosegmental fusion with intraoperative three-dimensional navigation system in the treatment of high-grade developmental spondylolisthesis.

Background:The treatment of high-grade developmental spondylolisthesis (HGDS) is still challenging and controversial. In this study, we investigated the efficacy of the posterior reduction and monosegmental fusion assisted by intraoperative three-dimensional (3D) navigation system in managing the HGDS.Methods:Thirteen consecutive HGDS patients were treated with posterior decompression, reduction and monosegmental fusion of L5/S1, assisted by intraoperative 3D navigation system. The clinical and radiographic outcomes were evaluated, with a minimum follow-up of 2 years. The differences between the pre- and post-operative measures were statistically analyzed using a two-tailed, paired t-test.Results:At most recent follow-up, 12 patients were pain-free. Only 1 patient had moderate pain. There were no permanent neurological complications or pseudarthrosis. The magnetic resonance imaging showed that there was no obvious disc degeneration in the adjacent segment. All radiographic parameters were improved. Mean slippage improved from 63.2% before surgery to 12.2% after surgery and 11.0% at latest follow-up. Lumbar lordosis changed from preoperative 34.9 ± 13.3° to postoperative 50.4 ± 9.9°, and 49.3 ± 7.8° at last follow-up. L5 incidence improved from 71.0 ± 11.3° to 54.0 ± 11.9° and did not change significantly at the last follow-up 53.1 ± 15.4°. While pelvic incidence remained unchanged, sacral slip significantly decreased from preoperative 32.7 ± 12.5° to postoperative 42.6 ± 9.8°and remained constant to the last follow-up 44.4 ± 6.9°. Pelvic tilt significantly decreased from 38.4 ± 12.5° to 30.9 ± 8.1° and remained unchanged at the last follow-up 28.1 ± 11.2°.Conclusions:Posterior reduction and monosegmental fusion of L5/S1 assisted by intraoperative 3D navigation are an effective technique for managing high-grade dysplastic spondylolisthesis. A complete reduction of local deformity and excellent correction of overall sagittal balance can be achieved.

Progressive restoration of spinal sagittal balance after surgical correction of lumbosacral spondylolisthesis before skeletal maturity.

Spinopelvic alignment is crucial in assessing an energy-efficient posture in both normal and disease states, such as high-displacement developmental spondylolisthesis (HDDS). The overall effect in patients with HDDS who have undergone local surgical correction of lumbosacral imbalance for the global correction of spinal balance remains unclear. This paper reports the progressive spontaneous improvement of global sagittal balance following surgical correction of lumbosacral imbalance in patients with HDDS. The records of 15 patients with HDDS who underwent surgery between 2005 and 2010 were reviewed. The treatment consisted of L4-sacrum reduction and fusion via a posterior approach, resulting in complete correction of lumbosacral kyphosis. Preoperative, 6-month postoperative, and final follow-up postoperative angular measurements were taken from full-spine lateral radiographs obtained with the patient in a standard standing position. Radiographic measurements included pelvic incidence, sacral slope, lumbar lordosis, and thoracic kyphosis. The degree of lumbosacral kyphosis was evaluated by the lumbosacral angle. Because of the small number of patients, nonparametric tests were considered for data analysis. Preoperative lumbosacral kyphosis and L-5 anterior slip were corrected by instrumentation. Transient neurological complications were noted in 5 patients. Statistical analysis showed a significant increase of thoracic kyphosis on 6-month postoperative and final follow-up radiographs (p < 0.001). A statistically significant decrease of lumbar lordosis was noted between preoperative and 6-month control radiographs (p < 0.001) and between preoperative and final follow-up radiographs (p < 0.001). Based on the authors' observations, this technique resulted in an effective reduction of L-5 anterior slip and significant reduction of lumbosacral kyphosis (from 69.8° to 105.13°). Due to complete reduction of lumbosacral kyphosis and anterior trunk displacement associated with L-5 anterior slipping, lumbar lordosis progressively decreased and thoracic kyphosis progressively increased postoperatively. Adjusting the sagittal trunk balance produced not only pelvic anteversion, but also reciprocal adjustment of lumbar lordosis and thoracic kyphosis, creating a satisfactory level of compensated global sagittal balance.

Surgical treatment of high-dysplastic developmental spondylolisthesis in a child: A case report

Introduction: High-dysplastic developmental spondylolisthesis (HDDs) is extremely rare, comprising 5% of the total cases of spondylolisthesis. It can remain asymptomatic for a long time and can progress to a more severe grade of olisthesis and spondyloptosis. Opinions regarding the surgical management of highgrade dysplastic spondylolisthesis in children and adolescents still remain conflicting and controversial. case report: this case describes a 12-year-old girl with high-grade dysplastic L5-s1 spondylolisthesis with instability pain, managed with uninstrumented in situ circumferential fusion. the patient showed excellent clinical, functional and radiological outcomes at follow-up of 48th month. since, plain radiographs and conventional computed tomography (ct) scan failed to show convincing anterior intercorporal fusion, we did fusion analysis with a multi-slice helical tomography scan with multiplanar reconstruction. the reconstructed multiplanar images defined a good posterolateral and anterior intercorporal

Spondylolisthesis: Intra-rater and Inter-rater Reliabilities of Radiographic Sagittal Spinopelvic Parameters Using Standard Picture Archiving and Communication System Measurement Tools

Study DesignReliability analysis. ObjectiveTo determine the intra-rater and inter-rater reliability of common sagittal spinopelvic measurements from Digital Imaging and Communications in Medicine images on a commercial Picture Archiving and Communication system for patients with developmental spondylolisthesis. Summary of Background DataComputer-aided analysis of digital radiographs has been used in research protocols to define anatomic and positional characteristics of developmental spondylolisthesis. Previous studies have shown poor reliability and weak correlations of manual measurements used in clinical practice with research measurements, which limit the clinical value of prior research. MethodsFive raters of varying experience measured lateral spinopelvic images of 30 patients with developmental spondylolisthesis. Measurements were repeated after 1 week. Intra-rater and inter-rater reliabilities for each measurement were determined. Measurements were compared with those obtained from a computer-based image enhancement research system. Continuous variables were assessed by analysis of variance, whereas kappa statistics were determined for categorical variables. ResultsExcellent intraclass correlations (ICC)s were obtained for all radiographic measurements based on linear values (slip ratio and C7 balance) as well as pelvic tilt angle. Angular measurements had good to excellent ICC but were weaker when the sacral plate was involved. There was poor agreement with classification of sacral doming. Some measurements had reduced reliability in the images with evidence of doming. ConclusionsExcellent ICCs were found with measurements of from Digital Imaging and Communications in Medicine images using commercial Picture Archiving and Communication System tools. Sacral doming affected the reliability. A radiographic classification of spondylolisthesis will be most reliable when based on slip ratio, C7 balance, and pelvic tilt.

High-grade lumbosacral spondylolisthesis reduction and fusion in children using transsacral rod fixation

There is no consensus on how to treat surgically high-dysplastic developmental spondylolisthesis in children and adolescents. Although reducing spinal deformity seems mandatory, the issue of surgical reduction versus in situ fusion remains controversial. The files of 12 consecutive patients surgically treated for a grade 3 or 4 spondylolisthesis were reviewed. The treatment consisted in L4 to sacrum reduction and fusion by posterior approach. The reduction of lumbopelvic imbalance was made intraoperatively using a trans-sacral rod fixation technique. Mean preoperative L5 anterior slippage was 72.3 % (60 to 95 %). The mean preoperative lumbosacral tilt angle was 70.5° (43 to 92°). Mean final lumbosacral tilt angle was 102° (91 to 114°). Mean final L5 anterior slippage was 19 % (7 to 63 %). Neurological complications (radicular L5 or S1 deficits) were noted in five patients. At final follow-up L4 to S1 fusion was achieved in all patients. No patient had persistent deficit or radicular pain. The fusion rate in our series proved to be optimal. Thanks to the trans-sacral rod fixation, lumbosacral kyphosis correction was very good. The intrasacral positioning of the screws reduces the risk of implant prominence especially in such pediatric patients. We stress the importance to avoid complete slip reduction in such patients to minimize stretching on L5 and S1 roots. No additional immobilization is needed due to solid posterior instrumentation. Doing such procedure only by posterior approach avoids anterior approach-related complications.

Trans-sacral screw fixation in the treatment of high dyplastic developmental spondylolisthesis

We describe the case of a 67-year-old woman with L5-S1 ontogenetic spondylolisthesis treated with pedicle fixation associated with interbody arthrodesis performed with S1-L5 trans-sacral screwing according to the technique of Bartolozzi. The procedure was followed by a wide decompressive laminectomy. The patient had a progressive improvement of the symptoms which gradually disappeared in 12 mo. The radiograph at 6 and 12 mo showed complete fusion system. The choice of treatment in L5-S1 ontogenetic spondylolithesis is related to a correct clinical and diagnostic planning (X-ray, computer tomography magnetic resonance imaging, Measurement). In particular, the severity index and the square of unstable zone, and the standard measurements already described in the literature, are important to understand and to plane the correct surgical strategy, that require, in most of the times, fusion and interbody artrodesis.

“In situ” fusion or reduction in high-grade high dysplastic developmental spondylolisthesis (HDSS)

To assess if the evaluation of the spino-pelvic balance can be effective in the surgical decision making of the high-grade high dysplastic developmental spondylolisthesis (HDDS). Sixteen patients affected with high-grade HDDS (6 treated with "in situ" fusion, and 10 with reduction and fusion) were retrospectively evaluated. A clinical and radiological assessment of the deformity correction was carried out, with a minimum follow-up of 2 years. The differences between the pre- and postoperative measures were statistically analyzed using a two-tailed, paired t test. The six patients treated with "in situ" fusion showed no statistically significant change at the last follow-up relative to pelvic tilt (PT), sacral slope (SS), and grade, while the 10 patients treated with reduction showed significant changes: PT significantly decreased following surgery, while SS and grade significantly increased. The analysis of the spino-pelvic sagittal balance allows to identify two types of HDDS: the balanced deformities, which do not need reduction, and the unbalanced deformities, in which correction is needed.

The evaluation of lumbosacral dysplasia in young patients with lumbosacral spondylolisthesis: comparison with controls and relationship with the severity of slip

Comparison of lumbosacral dysplasia between normal individuals and patients with low and high grade spondylolisthesis has not been done previously. The objective of this study is to evaluate the relationship between lumbosacral dysplasia and severity of slip in young patients with lumbosacral spondylolisthesis. Postero-anterior and lateral radiographs of 120 normal individuals and 131 patients with developmental spondylolisthesis (91 low and 40 high grades) were reviewed. Quantitative evaluation of lumbosacral dysplasia was done using 6 criteria involving the degree of laminar dysplasia, degree of facet dysplasia, size of L5 transverse processes, L5/S1 disc height, type of sacral doming and L5 lumbar index. Subjects were categorized as having no/low, moderate or severe dysplasia based on the total dysplasia score. Comparisons in total dysplasia score between normal, low grade and high grade groups were performed and the correlation between degree of dysplasia and percentage of slip was assessed. Most normal individuals (88.3%) had no/low dysplasia; most patients with low grade spondylolisthesis (61.5%) had moderate dysplasia, while most patients with high grade spondylolisthesis (72.5%) had severe dysplasia. There was a significant difference in dysplasia between normal individuals and patients with spondylolisthesis. Dysplasia also varied significantly between low and high grade spondylolisthesis. There was a strong positive correlation (r = 0.63) between severity of dysplasia and percentage of slip. There is a significant relationship between the severity of spondylolisthesis and lumbosacral dysplasia, with mainly no/low dysplasia observed in controls and increasing total dysplasia scores in higher grades of spondylolisthesis. In addition, a variable degree of dysplasia was found within groups with low or high grade spondylolisthesis, suggesting that different subgroups of patients exist with regard to dysplasia. Thus the degree of dysplasia varies in spondylolisthesis and it is possible that different grades of dysplasia could relate to different prognoses or outcomes with treatment.

Spondylolisthesis in Twins

Report of a high dysplastic developmental spondylolisthesis in two identical twins of two unrelated families. To investigate the multifactorial etiology of developmental spondylolisthesis. Multiple studies have suggested an association between a high pelvic incidence and the presence of isthmic spondylolisthesis. Other studies suggest a genetic background for spondylolysis and a pattern of inheritance of susceptibility to spondylolysis and spondylolisthesis. Heterozygous cartilage-derived morphogenetic protein-1 (CDMP-1) mutation has previously been associated with spondylolysis and severe spondylolisthesis. Two identical female twins presented with a developmental spondylolisthesis. Pelvic parameters, lumbar lordosis and grade of spondylolisthesis were calculated on a lateral standing spine radiograph. MRI is performed to confirm a high dysplastic developmental spondylolisthesis. Blood sample of these four individuals were analyzed for the presence of a CDMP-1 mutation, a cartilage-specific member of the TGF-b superfamily of secreted signaling molecules that plays a key role in chondrogenesis, growth, and patterning of the developing vertebrate skeleton. PI, SS, PT, LL, and SI are significantly greater in all of these patients in comparison with the general population. Spinal MRI confirms a high dysplastic developmental spondylolisthesis in both twins. Mutation analysis of the two coding exons of CDMP-1 did not reveal any mutation in all four individuals. To our knowledge, this is the first report of a high dysplastic developmental spondylolisthesis in identical twins. The presence of a high dysplastic developmental spondylolisthesis in two identical twins shows the convergence in etiology of different factors such as genetics, maturation, critical age, female sex, high pelvic incidence. Although we cannot confirm that CDMP-1 mutation plays a key role in the etiology of spondylolysis/spondylolisthesis, neither can we rule out that CDMP-1 problems may be an etiology for at least a subpopulation of patients. However, the presence of a developmental spondylolisthesis in two sets of identical twins still suggests a genetic susceptibility to spondylolysis and spondylolisthesis.

Pre and post-operative assessment of sagittal balance for high-grade developmental spondylolisthesis

Pre and post-operative assessment of sagittal balance for high-grade developmental spondylolisthesis