髂腰韧带的横断位CT表现及其在腰骶部椎体节段定位中的价值

目的：初步研究髂腰韧带的横断位CT表现,重点探讨髂腰韧带在腰骶段移行椎中的定位作用。方法：选2008年5月至2010年3月因腰背部症状拟诊椎间盘病变来院行CT扫描的706例患者,其中男436例,女270例;年龄25～82岁,平均44岁。所有患者均进行单层螺旋CT横断位扫描,其中移行椎患者78例,均经X线摄片或透视证实。在横断面CT图像上观察髂腰韧带的形态、位置及走行,了解其位置是否相对恒定;研究髂腰韧带与腰椎节段的关系,并与另外4种常用的腰骶椎节段CT定位方法作对照。结果：628例具有正常腰骶节段的患者其髂腰韧带的主要部分均起自L₅横突,止于髂嵴,3例可见髂腰韧带细小分支从L_4,5椎间盘后外缘同时发出,其形态可分双束型占71.8%(451/628)及单束型占28.2%(177/628);78例移行椎患者的髂腰韧带亦起源于L₅横突;以髂腰韧带作为L₅椎体水平的定位标记,均得到准确定位,其准确率明显高于其他定位方法,与髂嵴定位法比较差异具有统计学意义(P<0.05).结论：髂腰韧带主体起源于L₅横突,其解剖位置相对恒定,可将其作为L₅的解剖定位标志,以判断腰骶部移行椎类型和进行椎间盘定位。     

The incidence of congenital lumbosacral malformations in young male Turkish military school candidates population

BackgroundDuring routine radiological examinations of the lumbar spine, congenital anomalies such as lumbosacral transition vertebra and scoliosis are frequently encountered in asymptomatic patients. They are not always associated with pathologies but have the potential to cause back pain in later times. The aim of this study is to analyze the prevalence of lumbar vertebral abnormalities in a group of young military school candidates who had no prior complaints.MethodsWe retrospectively evaluated the direct radiographs of asymptomatic young men aged between 17 and 22 applying between July 2018 and August 2018, for the routine check-up before becoming military school students. Exclusion criteria were prior history of low back pain for any reason, sciatica, neurogenic claudication, history of prior spinal surgery and history of a concomitant rheumatologic disease. All radiographs were evaluated for total lumbar vertebra number, morphology, presence of lumbosacral transitional vertebrae (LSTV), spina bifida occulta (SBO) and presence of lumbar and/or lumbar-elongated scoliosis.ResultsAll 3132 patients were male and mean age was 18.37. Out of them, 887 (28.3%) had a congenital lumbo-sacral anomaly that they were not aware of. The most common anomaly we detected was SBO, in 16.2% of the cases followed by LSTV with 12.9% of the cases. Some of the applicants had more than one anomaly in their X-rays.ConclusionCorrect identification of a lumbar abnormalities is of great importance, especially before surgical procedures. It is a known fact that most wrong-level spine surgery occurs in patients with variant spine anatomy, including LSTV. Meticulous screening and analyses should be performed to all patients scheduled for spinal surgery in order to avoid peri-operative complications and unwanted final results.     

Transsacral screw safe zone size by sacral segmentation variations

Variations in sacral segmentation may preclude safe placement of transsacral screws for posterior pelvis fixation. We developed a novel automated 3D technique to determine the safe zone size for transsacral screws in the upper two sacral segments in 526 adult pelvis computed tomography scans. Safe zone sizes were then compared by gender and sacral segmentation variations (number of neuroforamen and the presence/absence of lumbosacral transitional vertebrae, ±LSTV). Ten millimeters was used as the safety threshold for a large screw. 3 (0.6%), 366 (70%), and 157 (30%) sacra had 3, 4, or 5 neuroforamen, respectively. Eighty‐eight (17%) were +LSTV. Safe zone size depended on gender, number of neuroforamen in −LSTV sacra and presence of LSTV (p < 0.001) but not on the uni‐ or bilateral nature of the LSTV. 17% of −LSTV sacra were below the safety threshold in S1, 27% in S2, whereas 3% of +LSTV sacra were below in S1, 74% in S2. Of −LSTV sacra that cannot take an S1 screw safely, 77% can do so in S2, leaving only 4% of sacra that cannot accommodate a screw safely in either upper segment. The results demonstrate a predictable pattern of safe zone size based on gender and sacral segmentation variations. © 2014 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:277–282, 2015.

     

Regional variations in trabecular architecture of the lumbar vertebra: Associations with age,disc degeneration and disc space narrowing

Previous studies suggest that age and disc degeneration are associated with variations in vertebral trabecular architecture. In particular, disc space narrowing, a severe form of disc degeneration, may predispose the anterior portion of a vertebra to fracture. We studied 150 lumbar vertebrae and 209 intervertebral discs from 48 cadaveric lumbar spines of middle-aged men to investigate regional trabecular differences in relation to age, disc degeneration and disc narrowing. The degrees of disc degeneration and narrowing were evaluated using radiography and discography. The vertebrae were dried and scanned on a μCT system. The μCT images of each vertebral body were processed to include only vertebral trabeculae, which were first divided into superior and inferior regions, and further into central and peripheral regions, and then anterior and posterior regions. Structural analyses were performed to obtain trabecular microarchitecture measurements for each vertebral region. On average, the peripheral region had 12–15% greater trabecular bone volume fraction and trabecular thickness than the central region (p < 0.01). Greater age was associated with better trabecular structure in the peripheral region relative to the central region. Moderate and severe disc degeneration were associated with higher trabecular thickness in the peripheral region of the vertebral trabeculae (p < 0.05). The anterior region was of lower bone quality than the posterior region, which was not associated with age. Slight to moderate narrowing was associated with greater trabecular bone volume fraction in the anterior region of the inferior vertebra (p < 0.05). Similarly, greater disc narrowing was associated with higher trabecular thickness in the anterior region (p < 0.05). Better architecture of peripheral trabeculae relative to central trabeculae was associated with both age and disc degeneration. In contrast to the previous view that disc narrowing stress-shields the anterior vertebra, disc narrowing tended to associate with better trabecular architecture in the anterior region, as opposed to the posterior region.     

The clinical significance of lumbosacral transitional anomalies

Lumbosacral transitional vertebrae (LSTV) are common congenital anomalies of the human spine. In LSTV, either the fifth lumbar vertebra may show assimilation to the sacrum (sacralisation), or the first sacral vertebra may show transition to a lumbar configuration (lumbarisation). Although the condition has an incidence of over 12% in the general population, knowledge about the exact clinical implications is still lacking. The association between LSTV and low back pain has been debated since it was first described by Bertolotti almost a century ago. Furthermore, several conflicting studies have been published regarding the association of LSTV with other spinal pathology. There seems to be a relation with early disc degeneration above the LSTV in young patients. However, these differences fade with age as they are masked by other degenerative changes of the spine. From a practical view-point, failure to recognise and to number LSTV during spinal surgery may have serious consequences.     

Complete sacralization of L5 vertebrae: traits,dimensions, and load bearing in the involved sacra

Background ContextSpines with sacralized fifth lumbar vertebrae are quite commonly encountered. Sacralizations represent a transitional state at lumbosacral junctions and are more susceptible to degenerative changes resulting from the altered load-bearing patterns at these regions.PurposeThe present study is an attempt to analyze the morphology of sacra with complete and partially fused (sacralized) L5 vertebrae and compare it with those observed in normal sacra.Study Design/SettingMeasurements of dimensions and articular surface areas were recorded in samples bearing sacralized L5 vertebrae and in normal sacra. Relative contributions of dimensions and surface areas on the bone were worked out by calculating indices. Comparison with the normal sacra was expected to yield significant differences.Outcome MeasuresMeans of all linear parameters and indices were compared between sacralized and normal samples and between the fused and unfused sides of unilaterally sacralized specimens. Unpaired Student t test was applied to assess the differences in the values.MethodsSeven linear dimensions and five surface areas were measured in 330 sacra. Nine indices were formulated from them. Sixteen (4.8%) sacra presented with bilateral completely fused L5 vertebrae with the first sacral segments. Four (1.2%) showed unilateral complete unification of sacra with the transverse process of the L5 vertebra above. Parameters were compared between the normal and sacralized samples and also between the two varieties of sacralized specimen.ResultsSacra with fused L5 possessed significantly smaller heights than the normal ones if the fused L5 vertebra was excluded from the measurements. On inclusion of the L5, these sacra presented a grossly reduced distance between the zygapophyseal facets, a greater distance of the coronal plane of the facet joints from the posterior aspect of the L5, a narrower interauricular distance, slightly increased body width at the top of the sacrum (now L5), a comparable auricular surface area (with inclusion of the fusion of L5 transverse process at the lateral mass) to the normal ones, attenuated facet area, and occasionally, small intervertebral space between L5 and S1. The unilaterally fused variety exhibited overall smaller dimensions. None of these sacra showed accessory articulations at their ala. The auricular surfaces in these sacra spanned from mid-L5 to mid-S2 segments. The fusion of L5 increased the sacral height, width, and auricular surface. The auricular surfaces appeared to be situated “low-down” in context of the six (including L5) sacral segments.ConclusionsSacralization of L5 vertebra entails morphological alterations in the sacrum. The remnants of the original sacra in these specimens presented grossly diminished parameters. Sacralization of L5 possibly represents a structural and biomechanical adjustment to compensate for reduced joint interfaces associated with smaller sacra. It may correspond to one end of the transitional “spectrum,” the other end being defined by lumbarization of the S1 sacral segment.     

Onyiuke Grading Scale: A clinical classification system for the diagnosis and management of Bertolotti syndrome

BackgroundLumbosacral transitional vertebrae (LSTV) is a common anatomic variant of the spine, characterized by the formation of a pseudoarticulation between the transverse process of the lumbar vertebrae and sacrum or ilium. LSTVs have been implicated as a potential source of low back pain – dubbed Bertolotti syndrome. Traditionally, LSTVs have only been subdivided into types I–IV based on the Castellvi radiographic classification system.ObjectiveSolely identifying the type of LSTV radiographically provides no clinical relevance to the treatment of Bertolotti syndrome. Here, we seek to analyze such patients and identify a clinical grading scale and diagnostic-therapeutic algorithm to optimize care for patients with this congenital anomaly.MethodsPatients presenting with back pain between 2011 and 2018 attributable to a lumbosacral transitional vertebra were identified retrospectively. Data was collected from these patients’ charts regarding demographic information, clinical presentation, diagnostic imaging, treatment and outcomes. Based on evaluation of these cases and review of the literature, a diagnostic-therapeutic algorithm is proposed.ResultsBased on our experiences evaluating and treating these patients and review of the existing literature, we propose a clinical classification system for Bertolotti syndrome: we proposed a 4-grade scale for patients with Bertolotti syndrome based upon location, severity, and characteristics of pain experienced due to LSTVs.ConclusionBased on our experience with the cases illustrated here, we recommend managing patients with LSTV based on our diagnostic-therapeutic algorithm. Moving forward, a larger prospective study with a larger patient cohort is needed to further validate the treatment paradigm.     

Determining the lumbar vertebral segments on magnetic resonance imaging.

STUDY DESIGN: A study to test the ability of an additional cervicothoracic localizer scan to decrease interobserver discrepancy in the identification of vertebral segments in magnetic resonance imaging of the lumbar spine. OBJECTIVES: To investigate whether lumbar vertebral segments can be identified correctly from lumbosacral magnetic resonance localizer scans, the degree of interobserver discrepancy, and the value of an additional cervicothoracic localizer scan. SUMMARY OF BACKGROUND DATA: In magnetic resonance imaging of the lumbar spine, it may be difficult to identify transitional lumbosacral vertebral segments. METHODS: The sagittal and coronal lumbosacral localizer scans of 141 consecutive patients referred for magnetic resonance imaging of the lumbosacral spine were reviewed independently by two radiologists with the aim of locating the L5 vertebra. An additional sagittal cervicothoracic localizer scan also was performed in each case. The final study group consisted of 129 patients. The L5 vertebra was identified by counting caudally from C2 using the sagittal cervicothoracic and lumbosacral localizer scans. In the 54 most recently studied patients, cod liver oil capsule surface markers were placed near the thoracolumbar junction to quantify any marker shift between the two sagittal localizer scans. RESULTS: The lumbar segments could be identified consistently by counting caudally using cervicothoracic and lumbosacral localizer scans. Using sagittal lumbosacral localizer scans alone, the lumbar vertebral segments could be identified correctly in only 80.2% of patients. Coronal lumbosacral localizer scans produced similar results (82.2%). The accuracy fell to 77.9% when using a combination of both sagittal and coronal lumbosacral localizer scans. There was a 11.6% interobserver discordance in assessment of these levels. Lumbosacral transitional vertebrae were identified in 17 patients (13.2%), including 8 sacralized L5 and 9 lumbarized S1 vertebrae. Apparent surface-marker shift between cervicothoracic and lumbosacral localizer scans was insignificant, averaging only 1.9 mm (range, 0.0-5.6 mm). CONCLUSIONS: The addition of a cervicothoracic localizer scan in magnetic resonance imaging of the lumbosacral spine is highly recommended.     

Quality-of-life and postoperative satisfaction following pseudoarthrectomy in patients with Bertolotti syndrome

BACKGROUND CONTEXTBertolotti syndrome is a clinical diagnosis given to patients with back pain arising from a lumbosacral transitional vertebra (LSTV). A particular class of LSTV involves a pseudoarticulation between the fifth lumbar transverse process and the sacral ala, and surgical resection of the pseudoarticulation may be offered to patients failing conservative management. Bertolotti syndrome is still not well understood, particularly regarding how patients respond to surgical resection of the LSTV pseudoarticulation.PURPOSETo examine change in quality-of-life (QOL) and patient satisfaction following surgical resection of the LSTV pseudoarticulation in patients with Bertolotti syndrome.DESIGNAmbidirectional observational cohort study of patients seen at a single institution's tertiary spine center over a 10-year period.PATIENT SAMPLECohort consisted of 31 patients with Bertolotti Syndrome who underwent surgical resection of the pseudoarticulation.OUTCOME MEASURESPreoperative and postoperative Patient-Reported Outcomes Measurement Information System Global Health (PROMIS-GH) Mental and Physical Health T-scores, and a single-item postoperative satisfaction questionnaire.METHODSPatients were identified through diagnostic and procedural codes. Immediate preoperative PROMIS-GH scores available in the chart were gathered retrospectively, and postoperative PROMIS-GH and satisfaction scores were gathered prospectively through a mail-in survey.RESULTSMean (SD) improvement of PROMIS-GH Physical Health T-score was 8.7 (10.5) (p<.001). Mean (SD) improvement of PROMIS-GH Mental Health T-scores was 5.9 (9.2) (p=.001). When stratifying PROMIS-GH T-scores by response to the patient satisfaction survey, there were significant group differences in mean change for Physical Health T-scores (p<.001), and Mental Health T-score (p=.009). Patients who stated, “The treatment met my expectations” had much greater mean improvement in the PROMIS-GH T-scores.CONCLUSIONSPatients undergoing a pseudoarticulation resection procedure may experience a significant improvement in quality-of-life as measured by PROMIS-GH Mental and Physical Health.     

The prevalence of transitional vertebrae in the lumbar spine

Background context

Lumbosacral transitional vertebrae (LSTVs) are a congenital vertebral anomaly of the L5–S1 junction in the spine. This alteration may contribute to incorrect identification of a vertebral segment, leading to wrong-level spine surgery and poor correlation with clinical symptoms. Although several studies describe the occurrence of this anomaly in back pain populations, investigation of the prevalence in the American general population is lacking.

Purpose

To establish the prevalence rates for LSTVs in the general population.

Study design

Retrospective review.

Patient sample

Consecutive kidney-urinary bladder (KUB) radiographs of subjects from the past 2 years (2008–2009).

Outcome measures

Clinical demographics, number of lumbar vertebrae, L5–S1 transverse process (TP) height, and rib length.

Methods

Consecutive adult KUB studies of adult subjects were queried with clear visibility of the last rib’s vertebral body articulation, all lumbar TPs, and complete sacral wings. Exclusion criteria consisted of any radiologic evidence of previous lumbosacral surgery that would obstruct our measurements. A total of 1,100 abdominal films were reviewed, and 211 were identified as being adequate for the measurement of the desired parameters.

Results

Two hundred eleven subjects were identified as eligible for the study, and 75 (35.6%) were classified as positive for a transitional lumbosacral vertebra. The most common anatomical variant was the Castellvi Type IA (14.7%). The average age at the time of the KUB study was 59.8 years (18–95 years). One hundred ninety-seven subjects (93.4%) presented five lumbar (nonribbed) vertebrae, and only 14 (6.6%) had six lumbar vertebrae.

Conclusions

The significance of lumbosacral transitional level changes to the establishment of pain, degenerative changes, stenosis, and disc disease have been well documented in symptomatic patients. Although LSTV’s role in low back pain remains controversial, our study has shown that, when the same criteria are used for classification, prevalence among the general population and symptomatic patients may be similar.     

Identifying treatment patterns in patients with Bertolotti syndrome: an elusive cause of chronic low back pain

BACKGROUND CONTEXTBertolotti Syndrome is a diagnosis given to patients with lower back pain arising from a lumbosacral transitional vertebra (LSTV). These patients can experience symptomatology similar to common degenerative diseases of the spine, making Bertolotti Syndrome difficult to diagnose with clinical presentation alone. Castellvi classified the LSTV seen in this condition and specifically in types IIa and IIb, a “pseudoarticulation” is present between the fifth lumbar transverse process and the sacral ala, resulting in a semi-mobile joint with cartilaginous surfaces.Treatment outcomes for Bertolotti Syndrome are poorly understood but can involve diagnostic and therapeutic injections and ultimately surgical resection of the pseudoarticulation (pseudoarthrectomy) or fusion of surrounding segments.PURPOSETo examine spine and regional injection patterns and clinical outcomes for patients with diagnosed and undiagnosed Bertolotti Syndrome.DESIGNRetrospective observational cohort study of patients seen at a single institution's tertiary spine center over a 10-year period.PATIENT SAMPLECohort consisted of 67 patients with an identified or unidentified LSTV who were provided injections or surgery for symptoms related to their chronic low back pain and radiculopathy.OUTCOME MEASURESSelf-reported clinical improvement following injections and pseudoarthrectomy.METHODSPatient charts were reviewed. Identification of a type II LSTV was confirmed through provider notes and imaging. Variables collected included demographics, injection history and outcomes, and surgical history for those who underwent pseudoarthrectomy.RESULTSA total of 22 out of 67 patients (33%) had an LSTV that was not identified by their provider. Diagnosed patients underwent fewer injections for their symptoms than those whose LSTV was never previously identified (p = 0.031). Only those diagnosed received an injection at the LSTV pseudoarticulation, which demonstrated significant symptomatic improvement at immediate follow up compared to all other injection types (p = 0.002). Patients who responded well to pseudoarticulation injections were offered a pseudoarthrectomy, which was more likely to result in symptom relief at most recent follow up than patients who underwent further injections without surgery (p < 0.001).CONCLUSIONSUndiagnosed patients are subject to a higher quantity of injections at locations less likely to provide relief than pseudoarticulation injections. These patients in turn cannot be offered a pseudoarthrectomy which can result in significant relief compared to continued injections alone. Proper and timely identification of an LSTV dramatically alters the clinical course of these patients as they can only be offered treatment directed towards the LSTV once it is identified.     

Mini posterior lumbar interbody fusion with presacral screw stabilization in early lumbosacral instability

Background:Surgical options for the management of early lumbosacral spondylolisthesis and degenerative disc disease with instability vary from open lumbar interbody fusion with transpedicular fixation to a variety of minimal access fusion and fixation procedures. We have used a combination of micro discectomy and axial lumbosacral interbody fusion with presacral screw fixation to treat symptomatic patients with lumbosacral spondylolisthesis or lumbosacral degenerative disc disease, which needed surgical stabilization. This study describes the above technique along with analysis of results.Results:We had nine females and three males with a mean age of 47.33 years (range 26–68 years). Postoperative assessment revealed three patients to have screw placed in anterior 1/4^th of the 1^st sacral body, in rest nine the screws were placed in the posterior 3/4^th of sacral body. At 2 years followup, eight patients (67%) showed evidence of bridging trabeculae at bone graft site and none of the patients showed evidence of instability or implant failure.Conclusion:Presacral screw fixation along with micro discectomy is an effective procedure to manage early symptomatic lumbosacral spondylolisthesis and degenerative disc disease with instability.     

Morphometric analysis and identification of characteristic features in sacra bearing accessory articulations with L5 vertebrae

Background contextOccurrence of transitional vertebrae at the lumbosacral junction, especially accessory lumbosacral articulations (partial sacralization of the L5 vertebrae), is not uncommon. These transitional states are frequently associated with low back pain situations requiring surgical intervention.PurposeThe study aimed to investigate the presence of distinct morphological features and structural peculiarities associated with these sacra. The features related to sacra bearing L5-S1 transitions might be significantly different from those of the normal sacra. This study tries to understand whether accessory L5-S1 articulations demonstrate altered mechanisms of load transfer as a result of structural changes at the L5–S1 junction.Study designMorphometric measurements of several linear dimensions and articular areas were obtained from 332 sacra. Thirty sacra demonstrated unilateral accessory facets on their ala. Twelve sacra showed bilateral accessory lumbosacral articulations. Indices were calculated based on the linear dimensions and on the surface areas of the bones to detect proportional contributions of the dimensions and surface areas to the overall structure of all the sacra.Outcome measuresAll the parameters obtained from the transitional sacra were compared with the same parameters worked out on 290 normal sacra. All parameters in the sacra bearing accessory articulations were statistically compared with parameters in the normal sacra.MethodSeven linear dimensions and five surface areas were measured in 290 normal sacra. Thirty sacra bearing unilateral accessory articular facets and 12 sacra with bilateral accessory facets on their alae were measured for the same linear parameters and surface areas. Nine indices were calculated from these measurements in both the normal and transitional sacra and statistically verified.ResultsAnalysis of the results indicated that sacra bearing accessory articulations, in comparison to the normal, carried their auricular surfaces at a higher level; possessed load bearing features mainly confined to the two upper sacral segments; showed lesser distances between the facet joints; showed smaller distance of the coronal plane of the facet joints from the posterior aspect of the S1 vertebral body; exhibited smaller and more coronally oriented facet joint surfaces; and exhibited smaller body width and height. The auricular surface area and superior surface of the body of S1 in these “transitional” sacra were similar in comparison to normal sacra. Linear dimensions in sacra with bilateral accessory articulations were smaller than the ones having unilateral accessory L5-S1 articulations.ConclusionsLumbosacral accessory articulations constituted the bulk of transitional variations at the junction. Accessory articulations were unilateral (9%) and bilateral (3%) with a total of 12% of all studied samples (n=332) demonstrating this type L5–S1 transition. Sacra with lumbosacral pseudoarticulations were associated with different anatomical features in contrast to normal sacra. Analysis of these structural differences with the normal variants may possibly help in understanding the biomechanical properties at these transitional sites. Evaluation of the relative proportions of dimensions within these bones may help plan surgical interventions or probably predict the pattern of abnormal weight bearing in these sacra.     

Editorial Commentary: Restrictions in Spinal Motion Result in Lower Outcome Scores After Hip Arthroscopy

The critical consideration in determining the efficacy of hip surgery is patient-reported outcomes, specifically the achievement of the clinical threshold. Several studies examined the achievement of the clinical threshold following hip arthroscopy (HA) in the presence of coexisting lumbar spine disease. The condition related to the spine receiving a lot of focus in recent research is the lumbosacral transitional vertebrae (LSTV). However, this condition could be just the tip of the iceberg. To forecast the outcomes of HA, it is far more important to comprehend spinopelvic motion. Since higher-grade LSTV is associated with less lumbar spine flexibility and reduces the ability to antevert acetabulum, it is possible that LSTV severity or grading could be one of the indicators of less effective operation “especially in “hip users”‘ (hip users are defined as patents who are more dependent on on hip motion than spinal motion). In light of this, lower-grade LSTV ought to have a less significant impact on surgical outcomes than higher-grade LSTV.     

患椎间短椎弓根螺钉在单节段腰骶椎结核稳定性重建中的临床研究

目的证明后路患椎间短椎弓根螺钉固定治疗单节段腰骶椎结核的可行性,并探讨其适应证及疗效。方法 204例诊断明确、脊柱后凸畸形35°,符合纳入标准的单节段腰、骶椎结核患者,随机分为2组,均先进行后路矫形、内固定手术,同期或二期进行前路彻底病灶清除、椎体间自体髂骨支撑植骨融合术。其中短钉组104例,选用长20~35 mm的短椎弓根钉置于患椎椎弓根。如1个患椎剩余骨质1/3,而另1个患椎剩余骨质1/3,则行短钉、常规螺钉固定。长钉组:常规椎弓根螺钉置于患椎相邻的正常椎骨中,固定范围跨越患椎上、下各1个正常间隙。所有患者均采用四联化疗方案。结果 2组患者平均随访62.1个月。术后均无严重并发症发生,末次随访时,所有患者均治愈,无内固定松动及断裂现象。植骨平均愈合时间,短钉组4.3个月,长钉组4.6个月,Cobb角矫正度及丢失率2组分别为13.26°±3.76°,6.22%和16.35°±2.63°,5.24%,2组比较差异无统计学意义(P0.05),组内术前术后比较差异有统计学意义(P0.05)。血沉与C反应蛋白的术前术后差异无统计学意义。2组患者术后2年生活、工作基本恢复正常。短钉组患者术后功能恢复较长钉组好。结论腰、骶椎结核后路患椎间短椎弓根钉固定、前路病灶彻底清除术具有仅融合、固定病变节段,保留相邻正常的脊柱运动单元功能,术后脊柱功能恢复好等优点,具有很高的临床应用价值。     

Genetic regulation of cortical and trabecular bone strength and microstructure in inbred strains of mice.

The inbred strains of mice C57BL/6J (B6) and C3H/HeJ (C3H) have very different femoral peak bone densities and may serve as models for studying the genetic regulation of bone mass. Our objective was to further define the bone biomechanics and microstructure of these two inbred strains. Microarchitecture of the proximal femur, femoral midshaft, and lumbar vertebrae were evaluated in three dimensions using microcomputed tomography (microCT) with an isotropic voxel size of 17 microm. Mineralization of the distal femur was determined using quantitative back-scatter electron (BSE) imaging. MicroCT images suggested that C3H mice had thicker femoral and vertebral cortices compared with B6. The C3H bone tissue also was more highly mineralized. However, C3H mice had few trabeculae in the vertebral bodies, femoral neck, and greater trochanter. The trabecular number (Tb.N) in the C3H vertebral bodies was about half of that in B6 vertebrae (2.8(-1) +/- 0.1 mm(-1) vs. 5.1(-1) +/- 0.2 mm(-1); p < 0.0001). The thick, more highly mineralized femoral cortex of C3H mice resulted in greater bending strength of the femoral diaphysis (62.1 +/- 1.2N vs. 27.4 +/- 0.5N, p < 0.0001). In contrast, strengths of the lumbar vertebra were not significantly different between inbred strains (p = 0.5), presumably because the thicker cortices were combined with inferior trabecular structure in the vertebrae of C3H mice. These results indicate that C3H mice benefit from alleles that enhance femoral strength but paradoxically are deficient in trabecular bone structure in the lumbar vertebrae.     

The termination level of the conus medullaris and lumbosacral transitional vertebrae

Background

The presence of lumbosacral transitional vertebrae (LSTV) may affect the variation of the termination level of conus medullaris (TLCM). However, there have been few studies examining the association between the distribution of the TLCM and LSTV, especially in young patients. The purpose of this investigation was therefore to assess the relationship between the TLCM and LSTV in young patients.

Methods

A total of 379 patients with lumbar herniated disks were included in this study. There were 249 males and 130 females, with a mean age of 31 years (range 15–44). The patients were classified into three groups: (1) L4/TV group (7 %): 28 patients with sacralization of the fifth lumbar vertebrae; (2) L5/TV group (11 %): 41 patients with lumbarization of the sacrum; and, (3) normal group (82 %): 310 patients without LSTV. TLCM was assessed using MRI.

Results

The median TLCM of the normal, L4/TV and L5/TV groups was the middle third of L1, the upper third of L1 and the lower third of L1, respectively. The TLCM in the L4/TV group was significantly higher than that observed in the normal group (p < 0.001), while that in the L5/TV group was significantly lower than observed in the normal group (p < 0.001).

Conclusions

The presence of LSTV affected the variation of the TLCM. Therefore, the distribution of the TLCM with or without lumbosacral TV may help clinicians to identify the neurological discrepancies observed among neurologic injuries at the thoracolumbar junction.     

Development of a novel in vitro cadaveric model for analysis of biomechanics and surgical treatment of Bertolotti syndrome

BACKGROUND CONTEXTBertolotti syndrome (BS) is caused by pseudoarticulation between an aberrant L5 transverse process and the sacral ala, termed a lumbosacral transitional vertebra (LSTV). BS is thought to cause low back pain and is treated with resection or fusion, both of which have shown success. Acquiring cadavers with BS is challenging. Thus, we combined 3D printing, based on BS patient CT scans, with normal cadaveric spines to create a BS model. We then performed biomechanical testing to determine altered kinematics from LSTV with surgical interventions. Force sensing within the pseudojoint modeled nociception for different trajectories of motion and surgical conditions.PURPOSEThis study examines alterations in spinal biomechanics with LSTVs and with various surgical treatments for BS in order to learn more about pain and degeneration in this condition, in order to help optimize surgical decision-making. In addition, this study evaluates BS histology in order to better understand the pathology and to help define pain generators—if, indeed, they actually exist.STUDY DESIGN/SETTINGModel Development: A retrospective patient review of 25 patients was performed to determine the imaging criteria that defines the classical BS patient. Surgical tissue was extracted from four BS patients for 3D-printing material selection. Biomechanical Analysis. This was a prospective cadaveric biomechanical study of seven spines evaluating spinal motions, and loads, over various surgical conditions (intact, LSTV, and LSTV with various fusions). Additionally, forces at the LSTV joint were measured for the LSTV and LSTV with fusion condition. Histological Analysis: Histologic analysis was performed prospectively on the four surgical specimens from patients undergoing pseudoarthrectomy for BS at our institution to learn more about potential pain generators.PATIENT SAMPLEThe cadaveric portion of the study involved seven cadaveric spines. Four patients were prospectively recruited to have their surgical specimens assessed histologically and biomechanically for this study. Patients under the age of 18 were excluded.OUTCOME MEASURESPhysiological measures recorded in this study were broken down into histologic analysis, tissue biomechanical analysis, and joint biomechanical analysis. Histologic analysis included pathologist interpretation of Hematoxylin and Eosin staining, as well as S-100 staining. Tissue biomechanical analysis included stiffness measurements. Joint biomechanical analysis included range of motion, resultant torques, relative axis angles, and LSTV joint forces.METHODSThis study received funding from the American Academy of Neurology Medical Student Research Scholarship. Three authors hold intellectual property rights in the simVITRO robotic testing system. No other authors had relevant conflicts of interest for this study. CT images were segmented for a representative BS patient and cadaver spines. Customized cutting and drilling guides for LSTV attachment were created for individual cadavers. 3D-printed bone and cartilage structural properties were based on surgical specimen stiffness, and specimens underwent histologic analysis via Hematoxylin and Eosin, as well as S-100 staining. Joint biomechanical testing was performed on the robotic testing system for seven specimens. Force sensors detected forces in the LSTV joint. Kruskal-Wallis tests and Dunnett's tests were used for statistical analysis with significance bounded to p<.05.RESULTSLSTV significantly reduces motion at the L5–S1 level, particularly in lateral bending and axial rotation. Meanwhile, the LSTV increases adjacent segment motion significantly at the L2–L3 level, whereas other levels have nonsignificant trends toward increased motion with LSTV alone. Fusion involving L4–S1 (L4–L5 and L5–S1) to treat adjacent level degeneration associated with an LSTV is associated with a significant increase in adjacent segment motion at all levels other than L5–S1 compared to LSTV alone. Fusion of L5–S1 alone with LSTV significantly increases L3–L4 adjacent segment motion compared to LSTV alone. Last, ipsilateral lateral bending with or without ipsilateral axial rotation produces the greatest force on the LSTV, and these forces are significantly reduced with L5–S1 fusion.CONCLUSIONSBS significantly decreases L5–S1 mobility, and increases some adjacent segment motion, potentially causing patient activity restriction and discomfort. Ipsilateral lateral bending with or without ipsilateral axial rotation may cause the greatest discomfort overall in these patients, and fusion of the L5–S1 or L4–S1 levels may reduce pain associated with these motions. However, due to increased adjacent segment motion with fusions compared to LSTV alone, resection of the joint may be the better treatment option if the superior levels are not unstable preoperatively.CLINICAL SIGNIFICANCEThis study's results indicate that patients with BS have significantly altered spinal biomechanics and may develop pain due to increased loading forces at the LSTV joint with ipsilateral lateral bending and axial rotation. In addition, increased motion at superior levels when an LSTV is present may lead to degeneration over time. Based upon results of LSTV joint force testing, these patients’ pain may be effectively treated surgically with LSTV resection or fusion involving the LSTV level if conservative management fails. Further studies are being pursued to evaluate the relationship between in vivo motion of BS patients, spinal and LSTV positioning, and pain generation to gain a better understanding of the exact source of pain in these patients. The methodologies utilized in this study can be extrapolated to recreate other spinal conditions that are poorly understood, and for which few native cadaveric specimens exist.     

Distribution and incidence of degenerative spine changes in patients with a lumbo-sacral transitional vertebra

The purpose of this prospective study was to determine the overall incidence and distribution of lumbo-sacral degenerative changes (i.e. disc protrusion or extrusion, facet degeneration, disc degeneration, nerve root canal stenosis and spinal stenosis) in patients with and without a lumbo-sacral transitional vertebra (LSTV). The study population consisted of 350 sequential patients with low back pain and/or sciatica, referred for medical imaging. In all cases CT scans of the lumbosacral region were obtained. In 53 subjects (15%) an LSTV was found. There was no difference in overall incidence of degenerative spine changes between the two groups. We did find, however, a different distribution pattern of degenerative changes between patients with and those without an LSTV Disc protrusion and/or extrusion occurred more often at the level suprajacent to the LSTV than at the same level in patients without LSTV (45.3% vs 30.3%). This was also the case for disc degeneration (52.8% vs 28%), facet degeneration (60.4% vs 42.6%) and nerve root canal stenosis (52.8% vs 27.9%). For spinal canal stenosis there was no statistically significant difference between the two categories. In conclusion, our findings indicate that an LSTV does not in itself constitute a risk factor for degenerative spine changes, but when degeneration occurs, it is more likely to be found at the disc level above the LSTV.