bluuebunny/crossref_metadata_2025 huggingface dataset:
Sagittal Deformity Correction during the Lateral Transpsoas Approach with Hyperlordotic Interbody Grafting, Adjunctive ALL Release, and Subsequent Smith–Peterson Osteotomy
Authors: Staub Blake , Holman Paul , Hanson Darrell , Huang Meng
Published: May 2015

Introduction

Traditionally, surgical intervention for patients with thoracolumbar sagittal imbalance relied on posterior column shortening techniques such as the Smith–Peterson osteotomy (SPO) and pedicle subtraction osteotomy (PSO). The lateral retroperitoneal, transpsoas approach has been proven to afford significant coronal deformity correction; however, the evidence for its use in the sagittal deformity correction is less robust. Recently, the use of hyperlordotic grafts has provided all the benefits of the transpsoas approach while also allowing for sagittal deformity correction. Hyperlordotic interbody grafts and a subsequent SPO can theoretically provide a similar sagittal correction as provided by a PSO or multiple SPOs while minimizing the associated morbidities.

Materials and Methods

This is a retrospective review examining the preoperative and postoperative segmental lordosis after placement of a hyperlordotic cage and subsequent SPO. A total of 22 patient charts were reviewed. The mean patient age was 58.6. There were 8 males and 14 females. A 20-degree hyperlordotic cage was utilized at four intervertebral levels. The 30-degree cage was used at 19 levels. The surgical procedure involved the release of the anterior longitudinal ligament and placement of a hyperlordotic graft (NuVasive CoRoent XL-Hyperlordotic) via the lateral, retroperitoneal, transpsoas approach followed by posterior instrumentation and SPO at that level. In each instance, the hyperlordotic graft and subsequent SPO were part of a large, multilevel deformity correction and were not simply performed as a standalone procedure.

Results

Hyperlordotic cages were placed from T12–L1 to L4–L5 in this series. A total of 10 cages were placed at the L3–L4 interspace. The mean preoperative lordosis was 0.4 and 4.2 degrees in the 20 and 30-degree cohorts, respectively. The mean postoperative, segmental lordosis was 23.0 and 28.2 degrees in the two groups, yielding a mean correction of 22.6 degrees with the 20-degree cage and 24.0 degrees with the 30-degree cage. The 30-degree cage yielded a sagittal correction of 8.5 to 54.0 degrees. A correction of greater than 30 degrees was achieved in five cases. The single case with less than 10 degrees of lordosis restoration resulted from graft subsidence. The greatest increase in lordosis occurred in patients with the most significant preoperative segmental kyphosis.

Conclusion

Segmental lordosis increase of approximately 20 to 25 degrees can be expected with the placement of either a 20- or 30-degree hyperlordotic cage via the transpsoas approach with subsequent SPO at that level. This hybrid approach provides a degree of correction similar to a PSO without the associated morbidity.
Classification of Sagittal Imbalance Based on Spinal Alignment and Compensatory Mechanisms
Authors: Lamartina Claudio , Cecchinato Riccardo , Ismael Maryem , Damilano Marco , Berjano Pedro
Published: May 2015

Introduction

Sagittal balance is an independent predictor of clinical outcomes in spinal care. Surgical treatment is challenging and jeopardized by frequent complications. Guidelines for surgical treatment are currently not based on a classification of the disease. A comprehensive classification of sagittal balance, based on regional deformities and compensatory mechanisms combined with deformity patterns is proposed. Though the sagittal shape of the spine can change due to degeneration or trauma, correlations between sagittal shape parameters and pelvic incidence (PI) have been described. Pelvic incidence is not changed by degeneration, thus representing a permanent source of information on the original sagittal shape of the spine.

Material and Methods

A total of 128 full-spine lateral standing radiographs of patients with different spinal conditions were evaluated and classified by one rater. One random subseries of 35 patients was evaluated by two raters for calculation of interrater agreement. Spinopelvic parameters were measured in all the radiographs. The internal validity of the classification system was evaluated comparing the values of regional sagittal parameters that distinguish one category from the others.

Results

Eight different patterns were identified regarding the site of the deformity and the presence of compensatory mechanisms: cervical, thoracic, thoracolumbar junction, lumbar, lower lumbar, global and pelvic kyphosis, and normal sagittal alignment. Interrater agreement was almost perfect (j = 0.963). Statistically significant differences were found comparing the means of selected sagittal spinopelvic parameters that conceptually divide pairs or groups of categories: C2-C7 SVA for cervical kyphosis versus all other patients, TK-PI mismatch for thoracic kyphosis versus all other patients, T11-L2 kyphosis for thoracolumbar kyphosis versus all other patients, global alignment (LL? TK-PI) and SVA for lumbar kyphosis versus global kyphosis, and pelvic tilt for pelvic kyphosis versus lumbar, lower lumbar, and global kyphosis.

Conclusion

A comprehensive classification of sagittal imbalance is presented. This classification permits a better interpretation of the deformity and muscle forces acting on the spine, and helps surgical planning. Preliminary validation has been provided.
Effect of Age in Sagittal Spinal and Spinopelvic Alignment in a Brazilian Asymptomatic Sample
Authors: Barsotti Carlos Eduardo , Pratali Raphael , dos Santos Francisco Prado , Oliveira Carlos Eduardo , Nogueira Monica Paschoal
Published: May 2015

Introduction

The anatomical relationship between elements of the spinopelvic linear chain does not appear to be uniform across different ethnic and population groups, based on measurements of radiographic parameters presented in the literature in populations with different origins. These studies have demonstrated variability in spinal and pelvic parameters among the groups studied, which makes it important to know their normative values, specific for a population. Such knowledge enables surgeons to individualize treatment goals for deformities in a specific adult population. The aim of this study was to present normal values of sagittal spinal and spinopelvic parameters in a Brazilian population sample and analyze the effect of age on these parameters.

Materials and Methods

This is a prospective observational study involving asymptomatic volunteers in a Brazilian population sample. The volunteers that accepted to participate had obtained total spine radiography in addition to collecting demographic data, including age and sex. The radiographic parameters evaluated were: Sagittal vertical axis (EVS), T1-spinopelvic inclination (T1-SPI), pelvic incidence (PI), sacral slope (SS), pelvic tilt (PT), lumbar lordosis (LL), and thoracic kyphosis (TK). We also consider the mismatch between the PI and the LL (PI-LL). These radiographic parameters were compared between the age groups of volunteers, divided into three groups: 18 to 39, 40 to 59, and older than 60 years.

Results

In total, 167 asymptomatic volunteers were enrolled, 105 women and 62 men with a mean age of 45.8 years (range, 18–74). In regards to the age group, 54 volunteers had 18 to 39, 79 had 40 to 59, and 34 had older than 60 years of age. The mean values of radiographic parameters in the total sample were: SVA −11.77 mm, T1-SPI- 5.47 degrees, IP: 46.93 degrees, PT: 13.77 degrees, SS: 33.05 degrees, LL: 54.53 degrees, PI-LL: −6.98 degrees, and TK: 40.54 degrees. Comparing the values regarding age, it was observed that higher the age of individuals is, occurs a statistically significant increase in the values of SVA, PT, T1-SPI, and PI-LL ( p < 0.001, < 0.001, 0.001, and 0.004, respectively).

Conclusion

The study presented normal values of sagittal spine and spinopelvic parameters in a sample of a Brazilian population, and also showed that there is an increase in anterior tilt of the trunk and a larger pelvic retroversion directly proportional to the increase in age of the individuals.
Successful Correction of Sagittal Imbalance can be Calculated on the Basis of Pelvic Incidence and Age
Authors: Cecchinato Riccardo , Damilano Marco , Ismael Maryem , Langella Francesco , Lamartina Claudio , Berjano Pedro
Published: May 2015

Introduction

Sagittal imbalance is an independent predictor of outcome in adult degenerative spinal deformity. Restoration of sagittal spinopelvic parameters correlates with a better postoperative outcome. Several methods of preoperative calculation for sagittal correction have been proposed, most of them geometrical. A nongeometrical method, based on data of spinopelvic relationships in normal subjects, that uses the patient's pelvic incidence and age to calculate target lumbar lordosis and thoracic kyphosis is proposed. The goal of this study is to describe and validate this nongeometrical method in terms of sensitivity and specificity to predict satisfactory spinopelvic alignment.

Materials and Methods

A retrospective cohort study of patients operated for sagittal imbalance with pedicle subtraction osteotomies (PSO). Two calculation algorithms (method a: LL = −[32.56 + PI × 0.54], method b: LL = −[PI + 10 degrees]); in both TK = PI/r (see text for definitions) obtain theoretical lumbar lordosis (LL) and thoracic kyphosis (TK) solely based on pelvic incidence and age, for surgical planning. The sample is categorized according to two parameters: planning goals (LL and TK) achieved or not and satisfactory alignment (SVA < 50 mm and PT < 20 degrees) achieved or not. Two × two tables are built and odds ratio, sensitivity and specificity and PPV/NPV are calculated for each planning method. Different levels of tolerance for undercorrection are analyzed to refine the use of the method.

Results

Of the 50 patients included in the study, 23 presented satisfactory alignment postoperatively. With a tolerance of hypocorrection of 10 degrees (LL) and 30 degrees (TK), correction target was achieved in 23 patients according to method a (S = 0.89, Sp = 0.87%, OR = 53.33 [95% CI: 9.677–293.931]; p < 0.001), 23 patients according to method b (S = 0.93, Sp = 0.91, OR = 131.25 [95% CI:17–1013]; p < 0.001). The best prediction of satisfactory alignment was obtained with method b and tolerance 0 degrees (LL) and 10 degrees (TK). All patients with complete correction of LL (both methods) achieved good alignment. Overall, 22 of the 24 (91%) patients with less than 10 degrees of undercorrection of LL (method b) achieved good alignment.

Conclusion

Calculation of the target lordosis based only in the value of PI and age is a reliable method that can predict good outcomes in terms of alignment. The rule LL = −(PI + 10 degrees) is an easy to calculate and very effective method of planning for lumbar lordosis and good alignment can be expected with high confidence when the final lordosis is within 10 degree of undercorrection. Including TK in surgical planning can improve the results in terms of restoration of the less known “spinopelvic balance” parameter.
New Instrumentation Technique for Growing Rod
Authors: Aydinli Ufuk , Kara Kursat , Yaray Osman , Mutlu Muren
Published: May 2015

Introduction

The spine is a key factor in the growth of thorax, abdomen, and pelvis. By the age of 5 years, the spine reaches 50% of its adult length. Therefore, spinal fusion in a 5-year-old child can result in about 12.5 cm loss of spinal growth. Disruption of the growth of the spine due to fusion performed in the treatment of early-onset scoliosis leads to thoracic insufficiency syndrome. The ideal technique should maintain the correction of the deformity, allow continued spinal growth, should not require postoperative immobilization, and also should have low complication rates. There are several growing rod techniques which have been defined but none of them fulfill all of these conditions. The aim of this article is to define a new modification on the growing rod technique.

Patients and Methods

Ten children have been operated in authors' institution, at an average age of 8 (range, 4–9) years. The surgical technique involved short segment instrumentation applied on the convex side of the apex of the deformity. Pedicle screws or hooks were used at stable anchor levels of the concave side of the deformity. Two rods, one proximal and one distal, were fixed to anchor sites and connected by a domino connector. After distracting the concave side, a transverse connector was used between the short segment and the long one, and this connector was compressed to maintain a translational force on the apex of the deformity. The frequency of lengthening procedure is 6 to 9 months.

Results

The average follow-up was 11 months. The average preoperative coronal plane curve was 46 degree and corrected to 13 degree showing 74% scoliosis correction after index surgery.

Conclusion

The main goal of the treatment of early-onset spinal deformities in children is to correct the deformity while maintaining the growth of the spine. All the described techniques up to now have been based on distraction of the concave side and the compression of the convex side of the deformity at stable vertebrae. The technique defined in this study, distracts the concave side while applying a translational force at the apex of the deformity by a transverse connector. The authors believe that this new technique will maintain more effective correction. Other advantages include less surgical dissection so less likely to cause a spontaneous fusion of the spine, shorter operation time, and low risk of surgery-associated complications. Long-term outcomes of the treatment by this new technique should be investigated by the mean spinal growth, and the correction of the spinal deformity.
Does the Position of the Aorta Change with the Altered Body Position in Ankylosing Spondylitis Patients with Thoracolumbar Kyphosis? A Magnetic Resonance Imaging Investigation
Authors: Qian Bang-Ping , Qu Zhe , Ji Ming-liang , Zhu Zezhang , Liu Zhen , Wang Bin , Sun Xu , Zhu Feng , Yu Yang , Qiu Yong
Published: May 2015

Introduction

Lumbar spine osteotomy has been widely adopted to correct thoracolumbar kyphosis in ankylosing spondylitis (AS) patients; however, catastrophic aortic complications may occur during the insertion of pedicle screws or the performance of osteotomy. To prevent these iatrogenic complications, it is essential to have a clear understanding of the spatial relationship between the aorta and the spine. Previous study reported that the aorta is positioned more anteromedially relative to the spine in AS patients with thoracolumbar kyphosis when compared with normal subjects. However, patients in the aforementioned study were performed computed tomographic scans in the supine position, which was different from the prone position adopted in surgery. To the best of our knowledge, no report has been published to investigate the difference in the position of the aorta relative to the vertebrae between supine and prone positions in AS patients with fixed thoracolumbar kyphosis. The objective of this study is to explore the differences in the anatomic position of the aorta relative to the spine between supine and prone positions in AS patients with thoracolumbar kyphosis.

Patients and Methods

From March 2013 to June 2014, 20 AS patients (19 males, 1 female) with thoracolumbar kyphosis with a mean age of 30.9 years (range, 19–46 years) were recruited into this study. Each patient received an axial MRI scan from T9 to L3 in both the supine and prone positions. The left pedicle-aorta (LtP-Ao) angle and LtP-Ao distance were measured at each level. Radiographs were analyzed to measure the global kyphosis (GK), thoracic kyphosis (TK), lumbar lordosis (LL), and the apex of the kyphotic curve was also recorded. The paired sample t-test was used to compare these parameters between different positions.

Results

At T9 to L3 levels, no significant difference was noted in LtP-Ao distances (43.84 vs. 44.58 mm; p = 0.054) and LtP-Ao angles (0.67 vs. 0.03 degrees; p = 0.058) for AS patients between supine and prone positions. The correlation analysis also revealed no significant correlation between shifting of the LtP-Ao angle and GK, TK, and LL at T9 to L3 levels in the prone position.

Conclusion

There is no significant change of the relative position between aorta and spine at T9 to L3 levels when patients change from supine to prone position. The result of this study suggested that in advanced stage of AS, the chronic inflammation may result in the firm adhesion between the aorta and anterior longitudinal ligament. Moreover, due to the reduced mobility and limited range of motion, the aorta is more vulnerable to be injured when the misplacement of pedicle screws and the stretching of the aorta occurs during surgery. Therefore, surgeons must keep this condition in mind to avoid catastrophic aortic complications.
Standalone Anterior Lumbar Interbody Fusion for Spondylolisthesis
Authors: Ghent Finn , Rao Prashanth , Keegan Lee , Reddy Rajesh , Mobbs Ralph J.
Published: May 2015

Introduction

Debate continues over the optimal approach for fusion of isthmic and degenerative spondylolisthesis. We favor anterior lumbar interbody fusion (ALIF) as it permits liberal discectomy and placement of a large, lordotic device which restores disc height and sagittal balance, reduces listhesis, and indirectly decompresses exiting nerve roots. There are only a few articles in the literature looking at the degree of reduction and the durability over time in patients undergoing ALIF with spondylolisthesis.

Material and Methods

We studied the initial degree of reduction achieved, and the durability of this reduction over time when ALIF was used for patients with isthmic and degenerative spondylolisthesis. Analysis of prospectively collected radiographic data was conducted. All patients with lumbar spondylolisthesis who underwent standalone ALIF between 2009 and 2013 by a single surgeon (R. J. M.) were included. Radiological analysis of slip percentage and disc height on preoperative, postoperative, and latest follow-up imaging was performed with Surgimap Spine software. Demographic factors, surgical data and radiological results were compared.

Results

Average patient age was 64.5 years (range, 37–84) with 16 females, 15 males. There were 36 levels treated with 20 at L4/5, 15 at L5/S1, and one at L3/4. Mean listhesis was 16% which immediately postoperatively reduced to 2.3%, but at latest follow-up had recurred to 58% of the original value. An average disc height increase of 184% was observed postoperatively. Analysis of these measurements showed a high degree of inter- and intraclass correlation. Mean follow-up was 17 months. BMI correlated with immediate postoperative reduction ( p = 0.004), as did posterior disc height ( p = 0.04). The overall radiological fusion rate was 91%. Three patients required subsequent posterior instrumentation, which will be discussed.

Conclusion

ALIF achieves disc height restoration and indirect listhesis reduction in isthmic and degenerative spondylolisthesis. Although this reduction may regress over time, we found it remained reduced by approximately 50% at latest follow-up. Around 10% of patients required further strengthening by posterior pedicle screw fixation. Standalone ALIF without posterior pedicle screw fixation is successful in the majority of patients with spondylolisthesis.
The Implications of Limited Decompression and Fusion or Decompression Alone Compared to Full Correction in Adult Deformity Surgery
Authors: Hawryluk Gregory , Berven Sigurd , Chou Dean
Published: May 2015

Introduction

Some patients request limited surgery instead of full deformity correction and stabilization because of the perceived lower morbidity, risk, and magnitude of surgery. This study is an attempt to evaluate outcomes in patient who select limited fusion/decompression compared with patients who elect to undergo complete deformity correction/stabilization.

Materials and Methods

We performed a retrospective review of consecutive adult spinal deformity patients treated over a 6 year period who had minimum 1 year of follow-up in the practice of a single spinal surgeon. Patients with cervical or pathological deformity were excluded. Some patients chose only to undergo partial corrections or decompression alone. We compared demographic data of patients choosing among these three options and additionally compared intraoperative blood loss, length of surgery, and length of stay. We also examined the early and late complication rate as well as the number of subsequent spinal surgeries. We additionally compared perioperative change in quality of life measures (ODI, VAS, and SF36v2).

Results

A total of 103 patients were identified, out of which 59 patients underwent full correction while 24 underwent partial correction and 20 underwent decompression alone. Full correction was achieved in 54 of the 59 patients (91.5%). Patients choosing full correction were significantly younger than those undergoing less than full correction ( p < 0.0001). Attempted full correction was associated with significantly longer length of stay ( p = 0.016), longer surgical duration ( p < 0.0001), and greater volume of intraoperative blood loss ( p = 0.002). There was no clear relationship between extent of surgery and rate of early complications. Late complication and reoperation rates increased as the extent of the initial surgery increased however these differences were not significant. Only 26.2% of patients provided quality of life data. Those undergoing full correction had greatest improvement in ODI, VAS, SF36v2 physical and mental scores, particularly when full correction was achieved. No statistical differences in quality of life measures were detected although type II error is probable.

Conclusion

Although full deformity correction is more resource intensive and associated with a higher reoperative rate, our results suggest that achieving full deformity correction may achieve the greatest improvement in quality of life measures. A low response rate on quality of life measure surveys limits the strength of our conclusions.
The Presence of Preoperative Cervical Deformity in Adult Spinal Deformity Patients is a Strong Predictor of Inferior Outcomes and Failure to Reach MCID at 2-Year Follow-Up: Analysis of 235 Patients
Authors: Ames Christopher , Passias Peter , Soroceanu Alex , Boniello Anthony , Scheer Justin , Schwab Frank , Shaffrey Christopher , Kim Han Jo , Protopsaltis Themistocles , Mundis Gregory , Gupta Munish , Klineberg Eric , Lafage Virginie , Smith Justin
Published: May 2015

Introduction

A high prevalence of cervical deformity (CD) has been identified among adult spinal deformity (ASD) patients undergoing surgical treatment. The clinical impact of this is uncertain. This study aims to quantify the difference in patient-reported outcomes among ASD patients based on presence of CD before treatment.

Material and Methods

Retrospective review of a multicenter prospective database of surgical ASD patients with 2-year follow-up. CD was defined as: C2C7 SVA > 4 cm, cervical kyphosis (CK) C2C7angle > 0. Univariate testing was performed using t-tests, or tests of proportion. Multivariate models determined impact of preoperative CD on health-related quality of life (HRQL) scores (SF-36, ODI, and SRS) and obtaining minimally clinically important difference (MCID) at 2 years.

Results

A total of 235 patients met the criteria, of which 65 with preoperative C2C7 SVA > 4 cm, 57 with CK. Patients with and without CD saw improvements in 2-year HRQL scores ( p < 0.001). Overall, patients with preoperative CD had inferior postoperative HRQL and were less likely to achieve MCID for HRQL at 2-years. Those with preoperative SVA > 4 cm had worse ODI, PCS, SRS activity, appearance, pain, and total, and were less likely to meet MCID for ODI, PCS, SRS activity, and pain scores (odds ratio 0.39 for ODI CI 0.19:0.81 p < 0.05), (0.34 for PCS CI 0.16:0.72 p < 0.05), (0.29 CI 0.14:0.62 p < 0.05 SRS activity) (0.41 CI 0.20:0.86 p < 0.05 SRS pain). Similarly, patients with CK had inferior 2-year HRQL scores. Patients without any CD were four times more likely to reach 2-year SRS activity MCID (OR 0.40 CI 0.19:0.86 p < 0.05).

Conclusion

Despite experiencing significant improvements in HRQL scores, preoperative CD in ASD patients is a strong predictor of inferior outcomes and failure to reach MCID at 2-year follow-up. This information will help surgeons educate patients at risk for inferior outcomes and direct future research to improve patient outcomes.
Effectiveness and Safety of Convex Derotation in Thoracic Adolescent Idiopathic Scoliosis
Authors: Oggiano Leonardo , La Rosa Guido
Published: May 2015

Introduction

Concave derotation is the traditional correction maneuver in adolescent idiopathic scoliosis surgery. However, the positioning of thoracic pedicle screws at the concave side of the curve can be quite challenging, because of the small pedicle size and the wide variation in its morphological characteristics, due to the vertebral dystrophy observed in scoliotic patients. Then, to reduce risks of neural damages and ensure the same strength of derotation maneuver, a convex derotation through an all-level pedicle screws convex instrumentation can be performed. We report perioperative and 1-year results in a consecutive series of patients treated by convex derotation through an all-level pedicle screws convex instrumentation.

Materials and Methods

From January 2013 to January 2014, we surgically treated 24 consecutive patients (18 female patients and 6 male patients, mean age 13 years) affected by thoracic adolescent idiopathic scoliosis (Lenke Type 1, 19 patients, and Lenke Type 2, 5 patients). Mean preoperative Cobb angle was 56 ± 6 degrees in Lenke Type 1 group and 51 ± 4 degrees plus 32 ± 3 degrees in Lenke Type 2 group. We performed a posterior access only in patients using polyaxial pedicle screws at each level on the convex side and two sublaminar acrylic loops (universal clamps) at the upper instrumented vertebra, to reduce the stiffness of the construct. Derotation maneuver was performed on the convex prebent rod. In all cases, motor-evoked potential monitoring was used. Mean follow-up time was 15 months.

Results

The average percentage of coronal correction was 76 ± 5% (mean postoperative Cobb angle 15 ± 4 degrees), with no neurological complications. Regarding the postoperative kyphosis, we observed a slight decrease in mean values compared with preoperative measurements (mean reduction of thoracic kyphosis 5 ± 2 degrees). At 1-year follow-up, no changes in coronal or sagittal plane were observed. The mean operative time was 210 ± 30 minutes, with a mean blood loss of approximately 500 ± 100 mL. Using the free-hand technique, the mean time of pedicle screws positioning in the thoracic area on the convex side was approximately 2 ± 1 minutes from T6 to T12 and approximately 4 ± 1 minutes from T3 to T5. Whenever included in the area of arthrodesis, T2 was usually instrumented with the universal clamps. Instead, T1 has never been included in the arthrodesis area.

Conclusion

This case-series study shows the effectiveness and safety of convex derotation in Lenke Type 1 and 2 scoliosis. The coronal correction obtained with this technique is comparable to that obtained with the traditional concave derotation. Other advantages are short operative time, low intraoperative blood loss, and, mostly, a reduced risk of neurological complications.
Surgical Treatment of Degenerative Disc Disease of L5/S1 with ALIF only (Standalone) versus Posterior Approach Pedicle Fixation: Comparative Retrospective Study
Authors: Tejeda Martin
Published: May 2015

Introduction

In the surgical treatment of degenerative disc disease, specifically in L5/S1 segment have been proposed various treatment modalities, the most used is posterior arthrodesis considered nowadays as the current gold standard.

Objective

This study aims to compare the results of two groups of patients with degenerative disc disease in terms of improvement in pain, functional scale, functional recovery time, and radiological lumbar lordosis correction.

Material and Methods

Two groups of patients diagnosed with degenerative disc disease (adult patients, chronic low back pain of more than 6 months duration, with failed previous treatment without radicular component, decreased height of intervertebral space, studies were compared retrospectively with plain X-ray, CT and MRI), operated from April 2009 to April 2014, with a minimum follow-up of 6 months and maximum of 4 years. A group of 25 patients was treated with arthrodesis using a posterior approach with fixation with pedicle screws and bone graft posterolateral from bone bank, while the second group of 22 patients was treated with technique ALIF with PEEK cage via anterior approach (standalone), with fixing screws to the platforms and bone grafting from bone bank. Pain and Oswestry functional index plus functional recovery time and return to work, as well as changes in radiological lumbar lordosis were compared. Operative time, bleeding, and hospitalization time were also compared. Statistics included measures of central tendency, and standard deviation for continuous variables, and frequencies and proportions for categorical variables were used. Student t-test was used to compare both groups to perform simultaneous and multivariate analysis clinical measures.

Results

We found improvement on the pain intensity visual analog scale, at least 50% of the intensity of initial pain, and in regard to functional scale ( p > 0.01), it was possible to improve the overall height of the intervertebral space the anterior approach which was not achieved by the posterior route. Moreover, significant differences of less surgical time, less bleeding, shorter hospital stay, and were found by the anterior approach to the posterior approach.

Conclusion

In this study was found for degenerative disc disease of L5/S1, a better surgical outcome by the anterior approach than the posterior approach in terms of pain and functional recovery in an average follow-up of 2 years.
Lateral Lumbar Interbody Fusion for the Correction of Spondylolisthesis and Adult Degenerative Scoliosis in High-Risk Patients: Early Results and Complications
Authors: Waddell Bradford S. , Briski David C. , Zavatsky Joseph M.
Published: May 2015

Introduction

Lateral lumbar interbody fusion (LLIF) by a transpsoas approach can avoid complications seen in other techniques. Lateral cages offer a larger cage and may increase stability by spanning the ring apophysis. Patients with multiple comorbidities, including smoking, diabetes, and obesity, have been shown to have decreased fusion rates. This study used computerized tomography (CT) scans to assess interbody fusion utilizing the LLIF technique in patients at high risk for nonunion and pseudoarthrosis.

Methods

We performed a retrospective review of patients who underwent LLIF between January 2008 and December 2013. A total of 64 patients with 151 levels underwent nonstaged or staged LLIF with posterior correction and augmentation. Per protocol, patients received CT scans at their 1-year follow-up. Of the 64 patients, 32 patients with 86 levels met inclusion criteria. Two board-certified musculoskeletal radiologists and the senior surgeon (J. Z.) assessed fusion.

Results

We performed six revision surgeries (18.75%). Other comorbidities included osteopenia/osteoporosis (46.8%), diabetes (25%), obesity (25%), and active smoking (25%), among others. Postoperative complications occurred in 15 patients (46.8%). Anterior thigh pain and weakness occurred in five patients (15.6%), all of which resolved by 6 months. There were five cases of delirium/postoperative confusion (15.6%). There were three cases of proximal junctional kyphosis, each requiring revision and cranial extension. Two cases of abdominal atonia occurred, one of which resolved at 1 year and the other still symptomatic at 1 year and 1 month. There were no cases of infection, ileus, UTI, catastrophic subsidence, DVT or PE. By CT scan assessment, each radiologist found solid fusion, as demonstrated by strong bridging trabeculae, was achieved in 84 out of 86 levels (97.6%). This was in agreement with the senior surgeon (J. Z.).

Conclusion

Several studies have evaluated LLIF fusion and reported fusion rates between 88 and 96%. Our results demonstrate high fusion rates (97.6%) using this technique, despite multiple comorbidities. Since stability plays a vital role in successful fusion, spanning the ring apophysis with a larger cage, along with pedicle screw supplementation, appear to be key factors.
Effect of Incidental Durotomy on Cost and Length of Stay in Primary, Short, Posterior Lumbar Fusion for Lumbar Spinal Stenosis: An Analysis of 17,232 Cases
Authors: Yoon S. Tim , Buck Stewart
Published: May 2015

Introduction

The incidence of durotomy and its economic impact during primary short lumbar fusion is not well described. The purpose of this study was to determine the incidence of and factors associated with durotomy in primary one- or two-level lumbar fusions performed for lumbar spinal stenosis and its impact on cost and hospital resource utilization.

Material and Methods

The Nationwide Inpatient Sample (NIS), was queried using ICD-9 codes for all primary one- or two-level lumbar fusions performed in adults for lumbar spinal stenosis between 2009 and 2011; only elective cases without concurrent diagnoses of vertebral infection, fracture, or tumor were included. Chi-square and t-tests were used as appropriate to compare categorical and continuous variables, respectively. Multivariate regression analysis was performed to identify factors independently associated with incidental durotomy, as well as total hospital charges and costs, as well as length of stay (LOS).

Results

A total of 17,232 procedures performed were identified, of which 801 had an incidental durotomy (rate of 4.65%). The rate of dural tears in teaching hospitals (5.09%; 95% CI: 4.66–5.55) was significantly higher as compared with nonteaching hospitals (4.19%; 95% CI: 3.77–4.66) ( p = 0.006). Multivariate regression analysis revealed that the odds of experiencing a dural tear increased by 2% with each year of increasing age (unit odds 1.02; 95% CI: 1.01–1.03). Incidental durotomy was associated with a mean 1.40-day (95% CI: 1.22–1.59) increase in hospital stay, a mean $10,885 (95% CI: $6,592–$15,177) increase in total hospital charges, and a mean $3,873 (95% CI: $2,502–$5,242) increase in estimated total costs (all differ from no durotomy group with p < 0.0001).

Conclusion

In this large retrospective series, the rate of incidental durotomy during primary short lumbar fusion for LSS fell within the range of previously reported rates. We have identified increasing age and surgery in a teaching hospital as factors associated with higher rates of durotomy. These findings are important given the significant financial and health care resource costs associated with dural tears.
A Cluster-Based Method for the Preoperative Identification of Lumbar Degenerative Patients having Higher Risk for Poor Global Outcome
Authors: Lazary Aron , Bozsodi Arpad , Klemencsics Istvan , Eltes Peter Endre , Varga Peter
Published: May 2015

Introduction

Surgery for lumbar disc degeneration has been shown to yield poor results in 10 to 45% of the patients. Evidence-based clinical tools for preoperative risk estimation would be very important to identify the “at-risk” patients. Several factors referring on the patients' symptoms, psychosocial issues, and medical history were previously published as significant individual risk factors on outcome, but there is low number of reports on integrative models with advanced statistics. The aim of this study was to identify significant outcome predictors and clinically different subgroups in patients surgically treated because of lumbar degenerative disc disease.

Patients and Methods

A total of 750 consecutive patients indicated for one- or two-level lumbar decompression/microdiscectomy or fusion surgery (TLIF) were recruited into the study. Patients with previous lumbar surgery or nondisc degeneration-related phenotype were not included into the analysis. Patients completed a questionnaire booklet containing the Oswestry disability index (ODI), visual analogue scales on low back (LBP), and leg pain (LP), Zung depression scale (ZDS), and the Modified Somatic Perception Questionnaire (MSPQ) before the surgery and 2 years after the surgery. Five-point Likert scale on self-reported outcome of the surgery was classified into two categories (“good” and “poor” outcome) and effect of preoperative parameters on that was determined applying uni- and multivariate logistic regression models. Two-step agglomerative cluster analysis was used to determine the best fit cluster structure of the cohort entering the significant outcome predictors into the model. Multivariate analysis of variance (MANOVA) and Fischer test were used to analyze the clinical clusters and their canonical discriminant functions. Chi-square tests were applied to investigate the clinical outcome in the different clusters.

Results

Four different preoperative parameters; number of spinal levels treated, severity of low back pain, duration of pain, and distress (calculated from ZDS and MSPQ scores) were proved to be significant predictors on surgical outcome in the final multivariate regression model ( p < 0.001). The four parameters identified four different subgroups in patients with good cluster quality. Clinical outcome was significantly different in the four preoperative patient-clusters (poor outcome in 5.1, 12.4, 20.9, and 25.6% of subjects, chi-square = 29.3, df = 3, p < 0.001).

Conclusion

Preoperative parameters of the patients with lumbar disc degeneration have got significant influence on the midterm surgical outcome. Outcome predictors determine different patient clusters with different risk for poor outcome. Advanced statistical approaches are advised to use in the future for patient stratification and risk estimation.
Postoperative Pain Control with Epidural Catheter after Posterior Lumbar Spine Fusion
Authors: Toktas Zafer , Yilmaz Baran , Eksi Murat , Konakci Murat , Aksoy Tamer , Urgun Kamran , Konya Deniz , Kilic Turker
Published: May 2015

Introduction

Pain management after posterior spinal fusion surgeries is a challenging topic. Epidural analgesia (CEA) technique has been developed to resolve some deleterious effects related with conventional intravenous patient-controlled analgesia (IV-PCA) method. However, studies are scanty in adult lumbar deformity patients. We hypothesized that CEA would be beneficial in adult lumbar deformity patients and conducted a study to observe effectiveness and safety of the procedure with a special consideration of the catheter level.

Patients and Methods

Forty-six patients scheduled for elective posterior lumbar spine fusion, in one spine-center clinic, were enrolled into the study. Three patients' dataset about pain control and/or sedation status were inconclusive and they were excluded from the final analysis. Pain and sedation status were evaluated with VAS and Ramsay sedation scales, respectively. Epidural catheter was inserted under direct visualization intraoperatively.

Results

There were 43 patients in the final analysis. Twenty-one patients had epidural catheters at or below the L2 level, 22 patients had their catheters above the predefined level. There was significant difference between the groups only in the 24th hour VAS scores. Patients with catheters of higher level location in the spinal canal, had higher VAS scores at the immediate postoperative period, however VAS scores in this group lessened more than the lower level catheter group at the 24th hour. Ramsay sedation scale score was significantly slightly higher in the patients with lower level catheters than the other group at 0 and the 2nd hour.

Conclusion

Continuous epidural analgesia is an effective and safe method in controlling postoperative pain in adult lumbar deformity patients treated with PSF method. Higher placement of epidural catheter in the spinal canal causes more pain at the beginning; however, drug release at this level has more effect over pain than lower levels.
Long-Term Effect of Selective Nerve Root Block in patients with Lumbar Stenosis
Authors: Jimenez Kathryn Anne , Sison Gerardo Juan
Published: May 2015

Introduction

Low back pain with radiculopathy is a common problem encountered both by the young and the elderly. In the young, it may be caused by HNP and/or chemical irritation causing nerve impingement. In the elderly, it is usually caused by a degenerative process causing stenosis. One problem faced by the surgeon is when the patient has an equivocal presentation; wherein surgical outcome becomes unpredictable. The aim of our study was to show the long-term effect of selective nerve root block, using a combination of lidocaine and methylprednisolone, in patients suffering from low back pain with equivocal presentation caused by lumbar spinal stenosis.

Materials and Method

This has a prospective study design, SNRB was done in patients with equivocal symptoms. A total of 19 patients who satisfied the inclusion criteria were included in the study, informed consent was granted by all the participants. All the patients already underwent at least eight sessions of physical therapy and took oral analgesics with no relief of symptoms. SNRB was done in a sterile environment with the guidance of an image intensifier. A combination of 1 mL methylprednisolone and 1 mL of 2% lidocaine was injected after verification of the needle position in two planes was done. The procedure was completed with the patient awake to elicit sensory changes to confirm proper positioning of the needle. Close follow-up was done at 1 week, 3 weeks, 3 months, 6 months, 1 year, and 3 years post-SNRB.

Results

After 1 week, 17 patients reported resolution of symptoms. Immediate relief was observed in 15 patients after the injection. At 1 year, all 17 patients still reported no recurrence of pain. Three were lost to follow-up, failing to return for the 3rd year post-SNRB, decreasing the success rate at 3 years to 15 patients out of 19. The remaining two patients required repeat SNRB, with one of the two eventually requiring surgical decompression.

Conclusion

This study showed that the combination of methylprednisolone and lidocaine was able to provide pain relief in 89% of the participants at 1 year follow-up, and 74% at 3 years. SNRB may be used in treating patients with equivocal presentation, providing faster relief than other conservative management, and evading unnecessary surgery.
A Quantitative Study of the Effects of High-Dose Parathyroid Hormone (1–34) and Low-Dose rhBMP-2 on Posterolateral Lumbar Spine Fusion in a Rabbit Model
Authors: Holmes Christina , Lina Ioan , Liauw Jason , Lo Sheng-Fu Larry , Theodros Debebe , Mao Annie , Elder Benjamin , Witham Timothy
Published: May 2015

Introduction

Parathyroid hormone (1–34) (PTH), which is commonly used in the treatment of osteoporosis, has been shown to increase bone mass and reduce the risk of fracture. Previously, we demonstrated that, while intermittent low-dose (10 µg/kg) PTH (1–34) treatment resulted in increased fusion mass volume, it did not improve biomechanical stiffness over the use of autograft alone, and did not improve fusion when combined with BMP-2 treatment (Lina et al, Spine [Phila Pa 1976]. 2014; 39(5):347). However, studies in other rodent models have indicated that the effects of PTH (1–34) on spinal fusion may be dose-dependent (Ming et al, Spine [Phila. Pa. 1976]. 2012; 37(15): 1275; Abe et al, Bone. 2007; 41(5): 775). These rat and mouse studies used PTH (1–34) doses as high as 20 to 40 µg/kg compared with the 10 µg/kg used in our experiments. We thus aim to evaluate whether increasing the dose of PTH (1–34) administered increases both the volume and biomechanical stiffness of the resulting fusion masses and/or exhibits synergistic effects with low-dose BMP-2 treatment.

Materials and Methods

A total of 60 rabbits underwent posterolateral intertransverse process lumbar spinal fusion surgery, and were assigned to one of the six groups depending upon the fusion grafting group employed: iliac crest autograft alone ( n = 10), iliac crest autograft + 20 µg/kg PTH (1–34) ( n = 10), iliac crest autograft + 40 µg/kg PTH (1–34) ( n = 10), rhBMP-2 alone ( n = 10), rhBMP-2 + 20 µg/kg PTH (1–34) and, rhBMP-2 + 40 µg/kg PTH (1–34). Fusion mass and quality were assessed using manual palpation, CT analysis of fusion mass volume, and four-point nondestructive biomechanical testing. Results/Conclusions: Although manual palpation is used as the standard measure of fusion, we found that CT analysis proved more effective in differentiating fused masses based on bone formation, not fibrous tissue. Both the PTH (1–34) group and BMP-2 increased bone density and volume of the fusion masses. Biomechanical analysis of fusion mass strength is currently underway.
IPD Coupled Decompression of Degenerative Spinal Stenosis: Comparative Results with Traditional Methods
Authors: Fokter Samo , Mirnik Nino
Published: May 2015

Introduction

The goal of this study was to obtain the success rate of decompression with concomitant interspinous process distraction device (IPD) implantation for degenerative lumbar spinal stenosis (DLSS) and to compare the results to historical series treated with traditional decompression with or without posterolateral (PL) instrumented fusion.

Material and Methods

This study prospectively analyzed the success rates of 18 DLSS patients treated with decompressive surgery and implantation of soft IPD (DIAM) at one or two levels. We compared the results with a historic group of 20 patients which were treated with traditional surgical decompression with or without PL fusion at one or two levels. In the DIAM group, outcomes were measured with the Zurich Claudication Questionnaire (ZCQ) and the short form health survey 36 (SF-36), completed preoperatively and at 6, 12, 24, and 48 months postoperatively. In the historic group, outcomes were measured with the ZCQ preoperatively and at 20.5 ± 10.5 months. The groups were compared in ZCQ results at 24 months. In the DIAM group, postoperative X-rays taken at 4 years were examined for erosions or fractures of the spinous processes

Results

The operating time was 89 (± 29) minutes in the DIAM and 139 (± 40) minutes in historic group. The blood loss was 265 (± 308) mL in the DIAM and 913 (± 630) mL in the historic group. The hospital stay was 6.3 (±2.4) days in the DIAM and 9.6 (± 5.4) days in the historic group. The narcotic use was 2.3 (± 1.5) days in the DIAM and 4.6 (± 2.6) days in the historic group. Overall, 61.1% (11/18) in the DIAM and 70% (14/20) of the patients in the historic group were considered to be clinically successful. In the DIAM group, SF-36 results significantly improved on follow-up at 6 months and continued to improve to 4 years. No erosions or fractions of the spinous processes were found on the X-rays in the DIAM group at the latest follow-up at 48 months.

Conclusion

The adjunct of a soft IPD to the decompression has provided patients with comparative results to traditional surgical methods. The main advantages of decompression coupled with soft IPD implantation for DLSS are shorter operating time, less blood loss, less hospital stay, and less narcotic use. The main disadvantage is increased cost of surgery.