Preoperative Spinopelvic Parameters Research Articles

Should the pelvis be included? An analysis of distal junctional failure risk factors in correcting adult spinal deformity in women with fusion to L5.

To identify the risk factors for distal junctional failure (DJF) in women treated for adult spine deformity with fusion to L5 and to highlight the significance of preoperative assessment, surgical decision-making, and postoperative care. This is a retrospective study of data collected prospectively on the local institutional spine surgery registry (2016-2021). All patients, women older than 18 years, with a diagnosis of adult spine deformity who underwent long posterior instrumentation to L5 and had a minimum of 2-years follow-up were included in the study (two groups: with or without DJF). Demographic and radiographic data, corrective strategy, preoperative level of degeneration at L5/S1 and GAP score were compared between the two groups. Forty-eight patients (n = 48) satisfied eligibility criteria. At two-years follow-up, nine patients (18,7%) developed a DJF that required surgical revision. Thirty-nine patients did not present distal junctional complications. Patients with or without DJF showed significant differences in terms of preoperative spinopelvic parameters (PT: 28°± 6° vs. 23°± 9°, p-value 0.05; DJF group vs. not DJF) and degeneration of L5-S1 (Pfirmann grade L5-S1 disc 3.7 ± 1.0 vs. 2.6 ± 0.8, p-value 0.001; DJF group vs. not DJF) (L5-S1 Facet joint Osteoarthritis 3.1 ± 0.8 vs.2.4 ± 0.8, p-value 0.023; DJF group vs. not DJF). DJF following spinal deformity correction surgery is influenced by a combination of patient-related, surgical and implant-related factors. Fusion construct length, preoperative and postoperative sagittal alignment and the grade of degeneration of the distal disc have been identified as significant risk factors. Surgeons should carefully evaluate these factors and employ appropriate strategies.

Validation of a preoperative formula to estimate postoperative pelvic sagittal alignment and mobility before performing total hip arthroplasty for patients with hip osteoarthritis

BackgroundAlthough it is important to consider pelvic alignment and mobility in the standing and sitting positions before THA, it is not known how to preoperatively predict individual postoperative pelvic alignment and mobility. The purpose of this study was to investigate the pelvic alignment and mobility before and after THA, and to develop a predictive formula using preoperative factors to calculate postoperative sagittal alignment and mobility.MethodsOne hundred seventy patients were assessed. The 170 patients were randomly divided into a prediction model analysis group (n = 85) and an external validation group (n = 85). In the prediction model analysis group, preoperative spinopelvic parameters were used to develop the predictive formulas to predict the postoperative sacral slope (SS) in standing and sitting positions and ΔSS. These were applied to the external validation group and assessed.ResultsR2 in multiple linear regression models for postoperative SS in standing, SS in sitting and ΔSS were 0.810, 0.672, and 0.423, respectively. The values of predicted and postoperative parameters were very close with no significant difference: SS in standing (33.87 vs. 34.23, P = 0.834), SS in sitting (18.86 vs. 19.51, P = 0.228), and ΔSS (15.38 vs. 14.72, P = 0.619).ConclusionThe present study showed that the pelvic alignment and mobility after THA can be predicted using preoperative factors. Although a model with higher accuracy is needed, it is important to use a predictive formula to estimate the postoperative condition before performing THA.

Pelvic Incidence-Lumbar Lordosis Mismatch Is Predisposed to Adjacent Segment Degeneration After Single-Level Anterior Lumbar Interbody Fusion: A Retrospective Case-Control Study.

Spinopelvic parameters play important roles in clinical outcomes and disability after short-segment fusion surgery for degenerative spine disease. This study aimed to investigate the relationship between preoperative or postoperative spinopelvic parameters and symptomatic adjacent segment degeneration (ASD) after single-level anterior lumbar interbody fusion (ALIF) surgery at the L4-5 segments. All patients who underwent single-level ALIF at the L4-5 level from January 2010 to December 2013 and were followed up for 5 years were analyzed. We collected the degree of degeneration at adjacent segments and preoperative and postoperative spinopelvic parameters. We compared the preoperative and postoperative parameters between patients with and without symptomatic ASD. Sixty-one patients were included in our study, and 30 patients had symptomatic ASD. Degeneration at adjacent segments and preoperative spinopelvic parameters did not affect the occurrence of symptomatic ASD. Patients with symptomatic ASD had higher postoperative pelvic tilt (PT) and a mismatch between lumbar lordosis (LL) and pelvic incidence (PI) compared to those without. Postoperative PT > 15° and PI-LL mismatch > 10° were significant risk factors for symptomatic ASD. High PT and PI-LL mismatch were significant risk factors for symptomatic ASD after single-level ALIF surgery. Spine surgeons should consider achieving proper LL to insert the cage at the appropriate angle and prevent a PI-LL mismatch value > 10° after single-level fusion surgery.

The use of lateral lumbar interbody fusion for identifying adult patients with spinal deformities treatable by short corrective fusion in 2-stage surgery

BackgroundTo investigate and compare the surgical outcomes of short and thoracopelvic corrective fusion with our two-stage technique using lateral lumbar interbody fusion (LLIF) and posterior open surgery. MethodsConsecutive patients with adult spinal deformities who underwent a planned two-stage anterior-posterior surgery, using LLIF for the first stage and posterior open corrective fusion for the second stage, with a minimum of 2 years of follow-up were included. Patients who underwent lumbar or lumbosacral corrective fusion and thoracopelvic corrective fusion were categorized into the short group and thoracopelvic groups, respectively. We investigated the spinopelvic parameters and patient-reported outcome measurements. ResultsSeventy-four consecutive patients (8 men, 66 women; average age, 70.0 years) were included. Ten patients underwent short corrective fusion following significant improvements in the symptoms and radiographic parameters post-LLIF. Several preoperative spinopelvic parameters were better in the short group. Compared to the thoracopelvic group, those who underwent short fusion had a poorer alignment 2 years postoperatively but with comparable results and a significantly higher function score on the Scoliosis Research Society–22 r (SRS-22r) questionnaire. The mean Oswestry Disability Index and SRS-22r scores significantly improved during the 2-year postoperative follow-up in both the groups. ConclusionsShort corrective fusion can be considered in patients whose symptoms and radiographic parameters significantly improve following LLIF. Patients who undergo short fusion with LLIF application have poorer alignment than those who undergo thoracopelvic fusion 2 years postoperatively; however, the results are comparable, and the function score is significantly improved.

Impact of the Preoperative Spinopelvic Parameters on the Segmental Lordosis Correction after One-level Lateral Lumbar Interbody Fusion.

Objectives The present study aimed to assess whether preoperative spinopelvic parameters can influence the gain of segmental lordosis after one level of lateral lumbar interbody fusion. Methods The following radiological parameters were measured in the X-rays: pelvic incidence, lumbar lordosis, pelvic tilt, L4S1 lordosis, index level segmental lordosis, intraoperative index segmental lordosis, pelvic mismatch (IP-LL), distal lordosis proportion, delta segmental lordosis, Pelvic Titlt (PT) > 20, actual sacral slope, and ideal sacral slope, and the correlation of these variables with the gain of segmental lordosis was investigated. Afterwards, an exploratory cluster analysis was performed to identify common characteristics between patients and segmental lordosis gain. Results The sample of the present study comprised 104 patients, of which 76% presented segmental lordosis gain. The most correlated parameters with the segmental lordosis gain were preoperative segmental lordosis (−0.50) and delta intraoperative lordosis (0.51). Moreover, patients in the high PI groups had a trend to gain more segmental lordosis ( p < 0.05) and a reduced risk of losing segmental lordosis (Odds 6.08). Conclusion Patients with low-medium PI profiles presented higher odds of loss of segmental lordosis. However, the preoperative spinopelvic parameters alone do not seem to play a significant role in the fate of segmental lordosis gain.

The Association Between Sagittal Spinopelvic Alignment and Persistent Low Back Pain After Posterior Lumbar Interbody Fusion for Treatment of Mild L5-S1 Spondylolisthesis: A Retrospective Study.

IntroductionThe aim of this study was to explore the association between sagittal spinopelvic alignment and persistent low back pain (PLBP) following posterior decompression and instrumented fusion for mild L5-S1 spondylolisthesis.MethodsBy retrieving medical records from January 2015 to April 2020, 200 patients following PLIF for mild L5-S1 spondylolisthesis were retrospectively reviewed. Patients were divided into two groups: PLBP group and non-PLBP group. The baseline characteristics and radiographic parameters were analyzed and compared between groups.ResultsThe PLBP group comprised 26 patients, and the non-PLBP group comprised 174 patients. No significant differences in preoperative spinopelvic parameters were found between the two groups (p > 0.05). There were statistically significant differences between the preoperative and postoperative variations of LL, SL, LSA, SD, and HOD spinopelvic parameters, regardless of group (p < 0.05). Postoperative PT and SS differed significantly between the PLBP group and non-PLBP group (p < 0.05). In the PLBP group, there were no significant differences between preoperative and postoperative PT; the same applied to SS. However, significant differences were found for the variations in preoperative and postoperative PT and SS between the two groups. The ΔPT was found as an independent risk factor for postoperative PLBP.ConclusionPatients with mild L5-S1 spondylolisthesis with PLBP after posterior lumbar spinal fusion had decreased SS and increased PT.

Effects of the difference between lumbar lordosis in the supine and standing positions on the clinical outcomes of decompression surgery for lumbar spinal stenosis.

The authors sought to evaluate the relationship between the difference in lumbar lordosis (DiLL) in the preoperative supine and standing positions and spinal sagittal alignment in patients with lumbar spinal stenosis (LSS) and to determine whether this difference affects the clinical outcome of laminectomy. Sixty patients who underwent single-level unilateral laminectomy for bilateral decompression of LSS were evaluated. Spinopelvic parameters in the supine and standing positions were measured preoperatively and at 3 months and 2 years postoperatively. DiLL between the supine and standing positions was determined as follows: DiLL = supine LL - standing LL. On the basis of this determination patients were then categorized into DiLL(+) and DiLL(-) groups. The relationship between DiLL and preoperative spinopelvic parameters was evaluated using Pearson's correlation coefficient. In addition, clinical outcomes such as visual analog scale (VAS) and Oswestry Disability Index (ODI) scores between the two groups were measured, and their relationship to DiLL was evaluated using two-group comparison and multivariate analysis. There were 31 patients in the DiLL(+) group and 29 in the DiLL(-) group. DiLL was not associated with supine LL but was strongly correlated with standing LL and pelvic incidence (PI) - LL (PI - LL). In the preoperative spinopelvic alignment, LL and SS in the standing position were significantly smaller in the DiLL(+) group than in the DiLL(-) group, and PI - LL was significantly higher in the DiLL(+) group than in the DiLL(-) group. There was no difference in the clinical outcomes 3 months postoperatively, but low-back pain, especially in the sitting position, was significantly higher in the DiLL(+) group 2 years postoperatively. DiLL was associated with low-back pain in the sitting position, which was likely to persist in the DiLL(+) group postoperatively. We evaluated the relationship between DiLL and spinal sagittal alignment and the influence of DiLL on postoperative outcomes in patients with LSS. DiLL was strongly correlated with PI - LL, and in the DiLL(+) group, postoperative low-back pain relapsed. DiLL can be useful as a new spinal alignment evaluation method that supports the conventional spinal sagittal alignment evaluation.

Correlation between clinical outcomes and spinopelvic parameters in patients with lumbar stenosis undergoing decompression surgery.

The aim of this study is to determine if there is a relation between preoperative sagittal alignment, based on radiographic parameters, and clinical outcomes, after lumbar decompressive procedures, in patients with lumbar spinal stenosis (LSS). This study enrolled patients with LSS who underwent lumbar decompressive procedures, between January 2016 and December 2017. Preoperative spinopelvic parameters were measured, and patients were divided into radiological groups according to the median of the following variables: relative lumbar lordosis (measured minus ideal lumbar lordosis), relative pelvic tilt (measured minus ideal pelvic tilt) and sagittal vertical axis (SVA). Clinical outcomes were compared between these groups and included the Core Outcome Measures Index, EuroQoL Five Dimension Questionnaire (EQ-5D) and Oswestry Disability Index (ODI) scores before and 1 year after surgery. Further correlation statistics between sagittal radiological measurements and the postoperative outcome scores were performed. The study included 104 patients. We did not find any clinically important difference in clinical outcomes between radiological groups. However, in correlation analyses we found a significant but weak statistical correlation between relative lumbar lordosis and both preoperative and postoperative ODI, as well as a significant statistical negative correlation between SVA and postoperative EQ-5D. Preoperative spinopelvic parameters did not significantly correlate with clinical outcomes after decompression surgery for LSS on non-deformity patients. Patients had a comparable improvement after surgery, regardless of their preoperative sagittal alignment.

Sagittal imbalance, muscle atrophy, and osteoporosis: risk factors for revision posterior lumbar fusion surgery in patients with Parkinson's disease.

The aim of our study was to evaluate features and complications of patients with Parkinson's disease (PD) who underwent posterior lumbar fusion surgery for lumbar degenerative diseases (LDD), as well as the risk factors for revision. Between January 2010 and December 2016, 132 patients were retrospectively identified for inclusion. Patients were divided into a 29 revision PD group and a 103 non-revision PD group. Patient factors included bone mineral density (BMD) and severity of PD using the Hoehn and Yahr staging system. Surgical factors included surgical levels and fusion methods. Radiographic measurements included pre-operative spinopelvic parameters, paraspinal muscle atrophy, and fatty infiltration. Logistic regression analysis was used to determine independent predictors for revision posterior lumbar fusion. The average age of the PD patients was 67.96years, and the follow-up time was 49.01months. R-PD patients accounted for 21.97% of all PD patients who underwent lumbar fusion surgery. Multivariable analysis indicated that low BMD (p = 0.012), fatty infiltration (p = 0.038), a smaller relative cross-sectional area (rCSA) of the paraspinal muscle (p = 0.008), larger pelvic incidence-lumbar lordosis (PI-LL) (p = 0.01), and sagittal vertical axis (SVA) (p = 0.004) were significant independent risk factors for revision posterior lumbar fusion in PD patients. PD patients with low pre-operative BMD, fatty infiltration, a smaller rCSA of the paraspinal muscle, and larger PI-LL and SVA had a higher rate of revision lumbar fusion. Maintaining sagittal balance, functional exercises, and anti-osteoporosis treatment were important in preventing complications in PD patients.

High-Grade Spondylolisthesis in Adults: Current Concepts in Evaluation and Management.

Information regarding the treatment of high-grade spondylolisthesis (HGS) in adults has been previously described; however, previous descriptions of the evaluation and surgical management of HGS do not represent more recent and now established approaches. The purpose of the current review is to discuss current concepts in the evaluation and management of patients with HGS. Literature review. HGS is diagnosed in up to 11.3% of adults with spondylolisthesis and typically presents as nonspecific lower back pain. Regarding evaluation, a thorough history and physical examination should be performed, which may help predict the presence of HGS. Diagnostic imaging, and specifically the use of spino-pelvic parameters, are now commonly implicated in guiding treatment course and prognosis. When surgical intervention is indicated, surgical approaches include in situ fusion variations, reduction and partial reduction with fusion, and vertebrectomy. Although the majority of studies suggest improvements with these approaches, the literature is limited by a low level of evidence with regards to the superiority of one technique when compared with others. HGS is a unique cause of low back pain in adults that carries considerable morbidity, but rarely presents with neurologic symptoms. Although the definitions, classifications, and methods of diagnosis of this spinal deformity have been established and accepted, the ideal surgical management of this deformity remains highly debated. Fusion in situ techniques are often technically easier to perform and provide lower risk of neurologic complications, whereas reduction and fusion techniques offer greater restoration of global spino-pelvic balance. Preoperative spino-pelvic parameters may have utility in assisting in procedural selection; however, future, higher-quality and longer-term studies are warranted to determine the optimal surgical intervention among the widely available techniques currently used, and to better define the indications for these interventions.

Minimally invasive multilevel lateral lumbar interbody fusion with posterior column osteotomy compared with pedicle subtraction osteotomy for adult spinal deformity

BACKGROUND CONTEXTPedicle subtraction osteotomy (PSO) is highly effective as a sagittal correction approach in patients with adult spinal deformity, but relevant issues such as surgical complexity and long-term complications limit its applicability. Recently, minimally invasive techniques have been reported to be useful for surgical treatment of adult spinal deformity; however, few reports have directly compared these techniques with PSO. PURPOSEThe purpose of this study was to evaluate the radiological and clinical efficacies of oblique lateral interbody fusion (OLIF) with posterior column osteotomy (PCO) using stiff rods (6.35-mm cobalt chrome [CoCr]). STUDY DESIGNRetrospective comparative study. PATIENT SAMPLEOne-hundred six patients (average age 71.3 years) diagnosed with adult spinal deformity presenting with sagittal imbalance for whom follow-up of over 2 years after sagittal correction (between 2013 and 2017) was available. OUTCOME MEASURESDescription and analysis of X-ray, computed tomography scans, operative time, estimated blood loss, and clinical outcomes (Oswestry Disability Index [ODI] and Visual Analog Scale [VAS]). METHODSA comparative analysis was performed evaluating spinopelvic parameters and clinical outcomes including the ODI, VAS, and complications in patients who underwent PSO (PSO group; n=65) or multilevel prepsoas OLIF combined with PCO and open posterior spinal fusion using 6.35-mm CoCr rods (OLIF group; n=41). The authors have no conflicts of interest to disclose. RESULTSThere were no differences in preoperative spinopelvic parameters between the PSO and OLIF groups. Although no differences were observed between the two groups in terms of postoperative SVA (−12.66 mm vs. −16.44 mm), postoperative lumbar lordosis (−71.46° vs. −72.55°), lumbar lordosis correction (77.96° vs. 73.54°), or postoperative pelvic tilt (9.35° vs. 7.17°), the estimated blood loss was significantly lower in the OLIF group (2824 mL vs. 1736 mL, p<.05). No differences were observed in clinical outcomes (ODI, VAS, and clinical complications), proximal junctional kyphosis, and spinopelvic parameters between the two groups 2 years after surgery. However, pseudarthrosis during the follow-up period, including rod fracture, occurred less frequently in the OLIF group compared with that in the PSO group (p<.05). OLIF was performed from the T12–L1 to L5–S1 regions (124 segments), with an average of three segments per patient. The computed tomography scans immediately after surgery showed an average segmental correction of −18° and 12.9% (16 segments) of 124 segments showed a correction angle of >30°. CONCLUSIONSMultilevel OLIF with PCO using a stiff rod to treat severe sagittal imbalance resulted in similar levels of sagittal balance and lordosis correction as obtained by PSO. Multilevel OLIF with PCO using a stiff rod can be an effective alternative to PSO for patients with severe sagittal imbalance.

260. How much lordosis can be restored by minimally invasive multilevel lateral lumbar interbody fusion combined with posterior column osteotomy using stiff rod (6.35 mm cobalt chrome) in adult spinal deformity surgery?

BACKGROUND CONTEXT Pedicle subtration osteotomy (PSO) is highly effective as a method for sagittal correction in patients with adult spinal deformity, but there are issues such as surgical complexity and long-term complications. Although, recently, minimally invasive techniques have been reported to be useful for surgical treatment of adult spinal deformity, few reports have directly compared it with PSO. PURPOSE The purpose of this study was to evaluate the radiological and clinical efficacies of lateral lumbar interbody fusion (LLIF) combined with posterior column osteotomy (PCO) using stiff rod (6.35 mm Cobalt Chrome; CoCr). STUDY DESIGN/SETTING Retrospective, consecutive case review. PATIENT SAMPLE A total of 106 patients (average age 71.5 years) who were diagnosed adult spinal deformity with sagittal imbalance and followed up for more than 2 years after sagittal correction OUTCOME MEASURES Description and analysis of X-ray and clinical questionaires (Oswestry Disability Index, Visual Analogie Scale) METHODS Comparative analysis was performed on the spinopelvic parameters and clinical outcomes of patients who underwent PSO (PSO group; n=65) and the patients who underwent multilevel pre-psoas LLIF combined with PCO and open posterior spinal fusion using 6.35 mm Cobalt Chrome rod (LLIF group; n=41). RESULTS There were no differences in preoperative spinopelvic parameters between PSO group and LLIF group. Although there were no differences between the two groups in terms of postoperative SVA (-12.7 mm vs -16.5 mm), postoperative lumbar lordosis (-71.5° vs -72.6°), lumbar lordosis correction (78.0°vs 73.5°), sacral slope (46.3° vs 49.1°) and pelvic tilt (9.4° vs 7.2°), estimated blood loss was significantly lower in the LLIF group (2,824 ml vs 1,736 ml, P=0.000). No differences were observed in the clinical outcomes (Oswestry Disability Index, Visual Analog Scale), proximal junctional kyphosis, and spinopelvic parameters between the two groups 2 years after the surgery, but reoperation due to pseudarthrosis was significantly higher in the PSO group (P=0.004). CONCLUSIONS Minimally invasive multilevel LLIF combined with PCO using a stiff rod leads to better clinical and radiological outcomes as much as PSO, accompanied by fewer long-term major complications, such as pseudarthrosis and reoperation. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.

Treatment of Adult Scoliosis Fractional Curve With Minimally Invasive Surgery: Anterior Versus Posterior Approach?

Abstract INTRODUCTION The fractional curve in adult scoliosis often causes radiculopathy and may be managed in varied manners with minimally invasive (MIS) deformity correction. There are inherent risks and benefits to anterior and posterior interbody reconstruction techniques, and the purpose of this study was to evaluate for differences in outcomes or complication rates by fractional curve treatment via MIS anterior vs. posterior interbody fusion METHODS Inclusion criteria were age = 18 yr, and one of the following: coronal cobb &gt; 20°, SVA &gt; 5 cm, PT &gt; 20°, PI-LL &gt; 10°. Patients were treated with circumferential MIS (cMIS) surgery or hybrid MIS surgery and had 2-yr minimum follow-up. Patient were divided into two groups: anterior or posterior interbody fusion at the lumbosacral junction (L4-S1). HRQOL measures included Oswestry Disability Index (ODI), visual analog score (VAS). RESULTS A total of 112 patients who underwent MIS adult deformity surgery with minimum 2-yr follow up. A total of 74 patients underwent anterior and 38 patients underwent posterior interbody reconstruction at L4-S1 utilizing MIS technique. Preoperative spinopelvic parameters, radiographic parameters, and VAS were not different, but ODI was higher in the anterior group (53 vs 48, P = .047). Complications and reoperation rates were not different (P = .089, P = .597), but posterior had more infections (15.8% vs 2.7%, P = .01). When subdivided for cMIS only surgery, 38 had anterior and 19 underwent posterior interbody fusions in the fractional curve. Pre- and postoperative VAS leg, ODI, and fractional curve magnitude were not different. In the anterior surgery cohorts, laminectomies at L4-S1 were performed in 22% of hybrid cases and in 8% of cMIS cases. CONCLUSION Treatment of the fractional curve of adult scoliosis appears to be similarly effective in reducing VAS, ODI, and fractional curve magnitude regardless of anterior vs posterior approach. However, posterior interbody reconstruction was associated with higher infection rate than anterior, regardless of application in cMIS or hybrid technique.

Spinopelvic Sagittal Alignment after Microendoscopic Laminotomy in Patients with Lumbar Degenerative Spondylolisthesis.

Spinopelvic sagittal balance is important in managing lumbar diseases. We evaluated the change in spinal sagittal alignment after microendoscopic laminotomy in patients with low-grade degenerative spondylolisthesis (DS). We retrospectively reviewed the records of 87 patients who underwent microendoscopic laminotomy. We enrolled 35 patients with DS and 52 patients without DS. Spinopelvic parameters were evaluated, including the sagittal vertical axis (SVA), lumbar lordosis (LL), sacral slope, pelvic tilt, and pelvic incidence (PI). Primary outcome was a change in spinopelvic alignment between the baseline and latest follow-up values (DS group versus non-DS group). Secondary outcomes were the relationships between improved global sagittal alignment and preoperative spinopelvic parameters. Both groups showed significantly alleviated low back pain (LBP), leg pain, and leg numbness. Preoperative SVA and PI were significantly higher in the DS group than in the non-DS group (p < 0.05). SVA significantly decreased and LL significantly increased in the DS group (p < 0.05), whereas those parameters did not differ significantly from before versus after surgery in the non-DS group. In both groups, SVA improvement correlated significantly with preoperative SVA (DS: r = 0.702; non-DS: r = 0.397). There was also a significant intergroup difference in the correlation coefficient (z = 1.98; r = 0.048). SVA and LL significantly improved after microscopic laminotomy in patients with low-grade DS and neurologic symptoms. SVA improvement in the DS group was correlated with preoperative spinopelvic sagittal imbalance. The strength of those correlations was greater in the DS group than in the non-DS group.

Analysis of Spinopelvic Parameters with L5 as the New Sacrum after Fusion in High-Grade Spondylolisthesis: A Possible Explanation for Satisfactory Results with In-Situ Fusion.

Study DesignRetrospective case series.PurposeTo correlate functional outcomes with spinopelvic parameters in patients with high-grade spondylolisthesis (HGS) treated with instrumented in-situ surgery or reduction and fusion.Overview of LiteratureSatisfactory functional outcomes are reported with reduction and in-situ fusion strategies in HGS. However, reasons for this are unclear. We hypothesize that following lumbosacral fusion, the L5 becomes part of the sacrum, which improves spinopelvic parameters, resulting in equivalent functional outcomes in both surgical methods.MethodsTwenty-six patients undergoing HGS (reduction group A, 13; in-situ group B, 13) were clinically evaluated using the Oswestry Disability Index (ODI), short form-12 (SF-12), and Visual Analogue Scale (VAS) scores. Spinopelvic parameters, including pelvic incidence, pelvic tilt (PT), sacral slope (SS), lumbar lordosis (LL), lumbosacral kyphosis (LSK) angle, and sacrofemoral distance (SFD) were measured preoperatively from S1 and postoperatively from L5 as the new sacrum at 1 year follow-up. Sagittal alignment was assessed using the sagittal vertical axis.ResultsBoth groups were comparable in terms of age, sex, severity of slip, and preoperative spinopelvic parameters (p>0.05). Postoperative VAS, SF-12, and ODI scores significantly improved in both groups (p<0.05). Compared with preoperative values, the mean postoperative PT, SFD, and LSK significantly changed in both groups. In reduction group, PT changed from 26.98° to 10.78°, SFD from 61.24 to 33.56 mm, and LSK from 74.76° to 109.61° (p<0.05). In in-situ fusion group PT changed from 26.78° to 11.08°, SFD from 62.9 to 36.99 mm, and LSK from 67.23° to 113.38° (p<0.05 for all). In both groups, SS and LL did not change significantly (p>0.05).ConclusionsAfter fusion, the L5 becomes the new sacrum and influences spinopelvic parameters to change favorably. This possibly explains why reduction and in-situ fusion achieve equivalent functional outcomes in HGS.

Comparative Study of Treatment of High Grade Spondylolisthesis—Reduction Vs In-situ Fusion: Do we Need to Rethink Assessment of Pelvic Parameters?

IntroductionReduction of high grade spondylolistheisis is considered to be the ideal treatment surgical treatment strategy on the premise that it restores spine biomechanics and altered sagittal balance. However it has been noted that in-situ fusion strategy also provide satisfactory result for high grade spondylolisthesis. In view of this observation we propose a hypothesis that following fusion L5 stands to be a part of the pelvis and pelvic parameter assessment should be considered with S1 pre-operatively and L5 post-operatively as the base of the pelvis. We assessd the pelvic parameters in this manner to guage the improvement in the pelvic parameters in both surgical groups (In –situ fusion Vs Reduction and fusion).Methodology: A retrospective review was conducted on 26 cases of high grade spondylolisthesis (defined as slippage > 50%) undergoing surgical treatment. Patients were divided into two groups; group one had undergone in-situ fusion and group two had undergone reduction with fusion. Spinopelvic parameters assessed for each group included; pelvic incidence (PI), pelvic tilt (PT), sacral slope (SS), lumbar lordosis (LL), lumbo-sacral kyphosis angle (LSK) and sacral femoral distance (SFD). Pre-operative spinopelvic parameters calculated with S1 were compared post-operatively with L5 as base of pelvis. Post-operative clinical outcomes were evaluated with Oswestry disability index (ODI score), Short form 12(SF 12) and visual analogue score (VAS score) for both groups. ResultsMean age was 34.1 years and mean follow-up was 24.5 months. Following surgery, VAS and ODI improved from 7.7 to 1.8 and from 62.6 to 14.7% respectively with no difference between two groups. One patient had transient L5 deficit in the reduction groupne procedure over the other. The mean pelvic parameters preoperatively were PI - 68.5°, PT - 26.7°, SS - 41.7°, LL - 51.4°, SFD - 63.0 mm, shift of L1 plumb line - 63.9 mm and LSK - 67°. With L5 as the new sacrum, in reduction group, significant changes were noted in PT (60.4%), SFD (45.25%) and LSK (46.6%) (p < 0.05 for all). Similar significant changes were noted in insitu fusion also in PT (58.6%), SFD (41.2%) and LSK (68.6%) (p < 0.05 for all). In both groups, the changes in PI, SS and lumbar lordosis were not significantly changed. The above results show that insitu fusion achieves the same changes in sagittal parameters when L5 is considered as part of the new sacrum. ConclusionsThe spinopelvic parameters for in-situ fusion and reduction with fusion groups, when utilizing the superior endplate of L5 did not show significant change in PI, SS and LL for both groups. Three parameters changed significantly post-operatively in both procedures and showed comparable changes – PT, SFD and LSK. This may suggest that the improved clinical outcomes for both treatment strategy may co-relate to changes in PT, SFD and LSK. The findings call for reevaluating the need for risky reduction procedures to establish normal pelvic parameters.

Sacroiliac Joint Syndrome 10 Years after Lumbar Arthroplasty: The Importance of Spinopelvic Alignment

Introduction Sagittal balance is an independent predictor of outcomes in spinal care and several authors focused their attention on the lumbar lordosis restoration as the key point to prevent secondary sacroiliac joint dysfunction (SIJD) after fusion. On the other hand, lumbar disc arthroplasty allows preservation of motion avoiding increased stress on the spinopelvic junction and preventing iatrogenic sagittal imbalance. Methods We analyze the incidence of a secondary SIJD and the spinopelvic alignment on a series of 31 consecutive lumbar disc prosthesis with a 10-year follow-up. Results Sagittal balance assessment showed no significant variation of preoperative spinopelvic parameters. Four patients (12%) presented a symptomatic SIJD. Only two of them required a percutaneous SIJ fixation. Both of them presented a fused L5–S1 prosthesis. Conclusions Very few studies are focused on the topic of SIJ deterioration after lumbar arthroplasty and, at the best of our knowledge, the present article is the first with such a long follow-up. After 10 years of the surgery 12% of our patients presented a symptomatic SIJ dysfunction, less than the percentage reported in the literature after lumbosacral fusion. The low rate of SIJD 10 years after lumbar arthroplasty might be explained by the preservation of the spinopelvic balance.

Restoration of the spinopelvic sagittal balance in isthmic spondylolisthesis: posterior lumbar interbody fusion may be better than posterolateral fusion

Background contextMore and more orthopedic surgeons recognize the importance of the sagittal balance of the spine. PurposeTo analyze the pre- and postoperative sagittal and deformity parameters of low-grade isthmic spondylolisthesis and evaluate the effect of posterolateral fusion (PLF) and posterior lumbar interbody fusion (PLIF) on spinopelvic sagittal balance. Study designNonrandomized controlled prospective study with a historical control. Patient sampleA total of 99 patients with low-grade L5–S1 isthmic spondylolisthesis were treated surgically; 36 patients (mean age, 60.2±5.2 years) received the PLF operation, and 63 patients (mean age, 57.1±6.9 years) chose the PLIF operation. The healthy control group was composed of 60 volunteers (mean age, 44.5±8.4 years). Outcome measuresThe pre- and postoperative spinopelvic and deformity parameters. MethodsAll patients had radiographs that allowed measurement of spinopelvic parameters before and after the operation. All the spinopelvic and deformity parameters were measured. Two radiologists measured the parameters with the Cobb method. ResultsAll of the preoperative spinopelvic parameters showed no difference between the PLIF and PLF groups in this study (p>.05). In both of the operation groups, the preoperative pelvic incidence, pelvic tilt (PT), sacral slope, lumbar lordosis (LL), and L5 incidence (L5I) were significantly higher than in the control group (p<.01); the height of the intervertebral disc (HOD) was significantly lower than the controls. There were no significant differences in PT among PLIF, PLF, and control groups after the operation (p>.05). LL increased in the PLIF group and decreased in the PLF group. The slip degree (SD) and L5I were restored significantly in both groups. The HOD of the PLIF group increased 5.04 mm, the postoperative HOD of the PLF group had no significant change. In both PLIF and PLF groups, the correction of SD was correlated with the change of LL (r=−0.398, p=.007; r=0.365, p=.022). The restoration of HOD in the PLIF group correlated with the change of LL (r=0.334, p=.011). No significant differences could be found between the short-term clinical outcomes of the PLF and PLIF. ConclusionEither PLF or PLIF would lead a great change in spinopelvic parameters and deformity parameters. The decrease of PT may be an important role for the short-term surgical outcome. The PLIF could increase the LL and form a more reasonable sagittal alignment. From the point of the sagittal spinopelvic balance, the PLIF may be better than the PLF for patients with isthmic spondylolisthesis.

Sacroiliac joint syndrome 10years after lumbar arthroplasty: the importance of spinopelvic alignment.

Sagittal balance is an independent predictor of outcomes in spinal care and several authors focused their attention on the lumbar lordosis restoration as the key point to prevent secondary sacroiliac joint dysfunction (SIJD) after fusion. On the other hand, lumbar disc arthroplasty allows preservation of motion avoiding increased stress on the spinopelvic junction and preventing iatrogenic sagittal imbalance. We analyze the incidence of a secondary SIJD and the spinopelvic alignment on a series of 31 consecutive lumbar disc prosthesis with a 10-year follow-up. Sagittal balance assessment showed no significant variation of preoperative spinopelvic parameters. Four patients (12%) presented a symptomatic SIJD. Only two of them required a percutaneous SIJ fixation. Both of them presented a fused L5-S1 prosthesis. The low rate of SIJD 10years after lumbar arthroplasty might be explained by the preservation of the spinopelvic balance.

Preoperative Planning for Pedicle Subtraction Osteotomy: Does Pelvic Tilt Matter?

Study DesignMulticenter, retrospective radiographic analysis. ObjectivesTo evaluate the impact that preoperative spinopelvic parameters have on postoperative sagittal vertical axis (SVA). The researchers hypothesized that patients with a large preoperative pelvic tilt (PT) would require more extensive lumbar pedicle subtraction osteotomy (LPSO) procedures to reestablish anatomic postoperative SVA than patients with normal preoperative PT. Summary of Background DataRestoration of anatomic sagittal spinal alignment has been demonstrated to improve clinical outcomes. However, the degree to which spinopelvic parameters contribute to sagittal spinal malalignment is poorly understood. MethodsMulticenter, retrospective analysis of 183 consecutively enrolled adult spinal deformity patients treated with LPSO procedures for correction of sagittal malalignment. Preoperative and postoperative freestanding full-length sagittal X-rays were analyzed for regional curves, pelvic parameters, and global alignment. Only patients with a preoperative SVA greater than 10 cm and a postoperative SVA less than 5 cm were retained for analysis. Patients were divided into 2 groups according to preoperative PT (low PT, less than 30°; and high PT, ≥30°). Independent t test analysis was used to determine differences in correction required to achieve postoperative SVA less than 5 cm. ResultsA total of 55 patients were identified for analysis. Low PT (n = 30) had lower preoperative PT than high PT (n = 25; 25° vs. 42°, respectively; p < .001). Analysis of the osteotomy performed demonstrated that the high PT group required a larger osteotomy resection (30° vs. 23°; p = .039) and a larger correction of lumbar lordosis (−43° vs. −31°; p = .006) to achieve an acceptable postoperative SVA (less than 5 cm). ConclusionsThis study demonstrates that patients with high PT in conjunction with sagittal spinal malalignment require larger lumbar osteotomy procedures, including a greater osteotomy resection and larger lumbar lordosis correction, to obtain a satisfactory postoperative SVA. Surgeons performing LPSO procedures must evaluate preoperative spinopelvic parameters, including PT, to avoid undercorrection and residual deformity after complex sagittal realignment procedures.