Identification and prediction of transitional vertebrae on imaging studies: anatomical significance of paraspinal structures

Complete lumbarization with calcified disc herniations at L5S1 and S1-2 levels treated with percutaneous endoscopic interlaminar discectomy: a case report and technique note

Objective

This study aims to report a case of a patient with complete lumbarization (Castellvi-IB) who developed symptomatic calcified disc herniations at L5S1 and lumbarized S1-2 levels and achieved excellent neurological recovery following percutaneous endoscopic interlaminar discectomy (PEID).

Summary of Background Data

In 1984, Castellvi et al. classified lumbosacral transitional vertebra (LSTV) into four types. They incorrectly classified I LSTV anomalies as only type I sacralization, not realizing type I lumbarization also belonged to type I LSTV, with the latter exhibiting a well-developed S1-2 disc (lumbosacral transitional disc, LSTD). Patients with type I lumbarization rarely develop calcified disc herniations concomitantly at L5S1 and LSTD levels. PEID has been developed to perform discectomy for neurological decompression at the lumbar region, especially at the lowest level where the higher iliac crest and/or widened transverse process exists.

Methods

A 47-year-old male presented to our hospital complaining of an intractable left leg radiating pain for 3 weeks after suffering from chronic radiating pain for 4 years. His physical examination found hyperalgesia at the lateral side of the left calf, decreased dorsal flexion strength of the ankle (grade 4/5), and a positive sign of straight leg raising test at the left side (30°). The preoperational Lumbar JOA (Japanese Orthopaedic Association) score was 12. Image examinations including whole spinal radiograph, MRI, and CT confirmed complete lumbarization (Castellvi-IB) with calcified disc herniations at L5S1 and LSTD levels at the left side. PEID was carried out at two index levels to accomplish decompression via the left approach.

Results

The patient's neurological function recovered quickly. One day postoperatively, he began to walk without discomfort. After 3 months, his muscle strength recovered to normal, and after 6 months, the residual dysesthesia at his posterolateral calf disappeared. The follow-up Lumbar JOA score was 26.

Conclusion

Calcified lumbar disc herniation could develop at two distal levels concomitantly in the case of type I complete lumbarization. This anomaly might be misinterpreted as a normal lumbar sequence by only lumbar MRI. PEID may be an effective procedure to treat such calcified disc herniations in a single visit.

Thoracolumbar transitional vertebrae: Quantitative differentiation and associated numeric variation in the vertebral column using skeletal remains

Transitional vertebrae at the thoracolumbar region are called thoracolumbar transitional vertebrae (TLTV) and retain physical features from the thoracic and lumbar regions. Since TLTV were first classified 40 years ago, there has been much discrepancy regarding its features, identification and clinical relevance. Vertebral body levels are used in the medical field as a frame of reference to locate specific organs, vessels, nerves or landmarks. Any numeric variation or deviation in the vertebral column may lead to clinical errors. Previous findings have suggested a high association between numeric variation and the presence of TLTV. Therefore, the aim of this study was to identify the types of TLTV observed and to identify any possible associated numeric variation in the vertebral column. This study also aimed to validate the established technique to quantitatively differentiate TLTV from T12 and L1 at the thoracolumbar junction using skeletal remains from a South African population group. Skeletal remains (n = 187) remains from the Pretoria bone collection were assessed. Measurements were taken of the angle of the superior zygapophyseal processes of the last thoracic vertebra (T12), the first lumbar (L1), and identified TLTV. The results indicate a TLTV prevalence of 35% (n = 66/187). The results show that each vertebral type (T12, L1, TLTV) fall into independent confidence intervals: T12 is 188° ± 9.22 (CI: 187° < μ < 189.6°), 110° ± 7.52 (CI: 109.2° < μ < 111.3°) in L1, and 135° ± 24.51 (CI: 130.4° < μ < 139.1°) in the TLTV. This study observed that 70% of cases with TLTV was associated with numeric variation in the spine, both homeotic and meristic and that TLTV has a 35% prevalence. The results clearly show that quantitative morphometric analysis can effectively differentiate TLTV from other vertebral types at the thoracolumbar junction in skeletal remains.

Prevalence of Lumbosacral Transition Vertebrae in Symptomatic Adults and the Levels of Degeneration in the Suprajacent Disc

Lumbosacral transition vertebra (LSTV) is a common occurrence and its prevalence ranges from 2.6% to 35.6%. Our aim is to study this phenomenon in the adult Singaporean population and assess the level of degeneration of the suprajacent disc in those with LSTV. Retrospectively, 545 patients (Age = 57.6 ± 18.3 years; Male = 277; Female = 268) who underwent radiographic evaluation of the lumbar spine for lower back pain or radicular symptoms were shortlisted. LSTV was found to be present in 106 patients (19.4%) with sacralization of L5 and lumbarization of S1 occurring in 96 patients (17.6%) and 10 patients (1.8%), respectively. The most common form of LSTV was Castellvi type IIA (46 patients; 43.4%). Based on Pfirrmann grading, Grade IV disc degeneration was most common in both the LSTV level (63%) and the unfused suprajacent level (77%) in those with LSTV. There was a significantly higher number of patients with grade IV and above degeneration in the suprajacent disc level among those with LSTV when compared to the last unfused (L5-S1) disc level in those without LSTV (84% vs. 65%; p = 0.0001). This suprajacent disc degeneration seen in patients with LSTV may contribute to low back pain and related problems in these patients.

Anterior spinal fusion (ALIF/OLIF/LLIF) with lumbosacral transitional vertebra: A systematic review and proposed treatment algorithm

•Key anterior approaches differences in LSTV include vascular (aortic bifurcation/iliocaval confluence), muscular (psoas) and osseus anatomy (inter-crestal tangent/pubic symphysis), when compared to non-LSTV.•There are increased surgical deviations but not significantly greater complications for anterior approaches in LSTV.•Vascular awareness while accessing L45 will be in the presence of a more cephalad ABF and ICC with sacralized L5, and access to the deeper L56 level will be in the presence of a more caudal ABF and ICC in lumbarized S1.

Prevalence of lumbosacral transitional vertebra among 4816 consecutive patients with low back pain: A computed tomography, magnetic resonance imaging, and plain radiographic study with novel classification schema

Study Design

A retrospective single-center study.

Background

The prevalence of the lumbosacral anomalies remains controversial. The existing classification to characterize these anomalies is more complex than necessary for clinical use.

Purpose

To assessment of the prevalence of lumbosacral transitional vertebra (LSTV) in patients with low back pain and the development of clinically relevant classification to describe these anomalies.

Materials and Methods

During the period from 2007 to 2017, all cases of LSTV were preoperatively verified, and classified according to Castellvi, as well as O'Driscoll. We then developed modifications of those classifications that are simpler, easier to remember, and clinically relevant. At the surgical level, this was assessed intervertebral disc and facet joint degeneration.

Results

The prevalence of the LSTV was 8.1% (389/4816). The most common L5 transverse process anomaly type was fused, unilaterally or bilaterally (48%), to the sacrum and were O'Driscoll's III (40.1%) and IV (35.8%). The most common type of S1-2 disc was a lumbarized disc (75.9%), where the disc's anterior-posterior diameter was equal to the L5-S1 disc diameter. In most cases, neurological compression symptoms (85.5%) were verified to be due to spinal stenosis (41.5%) or herniated disc (39.5%). In the majority of patients without neural compression, the clinical symptoms were due to mechanical back pain (58.8%).

Conclusions

LSTV is a fairly common pathology of the lumbosacral junction, occurring in 8.1% of the patients in our series (389 out of 4,816 cases). The most common types were Castellvi's type IIA (30.9%) and IIIA (34.9%) and were O'Driscoll's III (40.1%) and IV (35.8%).

Anatomy and morphology of iliolumbar ligament

PURPOSE

To address limited amount of available data and contradictory statements in published works 60 Iliolumbar ligaments extracted from 30 cadavers were examined to describe their insertions and morphology.

METHODS

The ligaments were removed during the standard autopsy procedures with a use of an oscillating saw, a chisel and a scalpel. The specimens were photographed before the extraction and measured alongside their anterior margin. Next, they were preserved in formaldehyde, stripped of other soft tissues and then examined, photographed and described.

RESULTS

The mean length of the ligaments was 31.7 mm. 44 specimens were described as single-banded, 13 as double-banded and 3 as other. In 24 cases costal process of L_V has been fixed to the iliac plate by short ligamentous bands. In 38 cases there was a thick fibrous membrane connected to the ligament. No legitimate insertions on L_IV vertebra were observed.

CONCLUSIONS

Typical iliolumbar ligament consists of a single ligamentous band. Most common variability of the ligament consist of two bands. In approximately 40% of cases the costal process of L_V can be additionally stabilized to the iliac plate by short, strong ligamentous bands. In 63% of cases a connection between the iliolumbar ligament and a fibrous membrane placed in the frontal plane, superiorly to the ligament, has been observed. There seems to be no convincing proof of existence of the insertion of the iliolumbar ligament on the L_IV vertebra.

The morphological consequences of segmentation anomalies in the human sacrum

OBJECTIVES

Despite the high frequency of segmentation anomalies in the human sacrum, their evolutionary and clinical implications remain controversial. Specifically, inconsistencies involving the classification and counting methods obscure accurate assessment of lumbosacral transitional vertebrae. Therefore, we aim to establish more reliable morphological and morphometric methods for differentiating between sacralizations and lumbarizations in clinical and paleontological contexts.

MATERIALS AND METHODS

Using clinical CT data from 145 individuals aged 14-47 years, vertebral counts and the spatial relationship between the sacrum and adjoining bony structures were assessed, while the morphological variation of the sacrum was assessed using geometric morphometrics based on varied landmark configurations.

RESULTS

The prevalence of lumbosacral and sacrococcygeal segmentation anomalies was 40%. Lumbarizations and sacralizations were reliably distinguishable based on the spatial relationship between the iliac crest and the upward or downward trajectory of the linea terminalis on the sacrum. Different craniocaudal orientations of the alae relative to the corpus of the first sacral vertebra were also reflected in the geometric morphometric analyses. The fusion of the coccyx (32%) was frequently coupled with lumbarizations, suggesting that the six-element sacra more often incorporate the coccyx rather than the fifth lumbar vertebra.

CONCLUSIONS

Our approach allowed the consistent identification of segmentation anomalies even in isolated sacra. Additionally, our outcomes either suggest that homeotic border shifts often affect multiple spinal regions in a unidirectional way, or that sacrum length is highly conserved perhaps due to functional constraints. Our results elucidate the potential clinical, biomechanical, and evolutionary significance of lumbosacral transitional vertebrae.

Psoas proximal insertion as a simple and reliable landmark for numbering lumbar vertebrae on MRI of the lumbar spine

OBJECTIVE

To evaluate the value of psoas muscle proximal insertion for correct numbering of the lumbar vertebrae in MRI, in particular in case of lumbosacral transitional vertebra (LSTV).

METHODS

Two radiologists assessed 477 MRI scans of the lumbar spine with a sagittal localizer sequence on the whole spine for numbering vertebrae caudally from C2. Proximal insertion of the psoas was determined as the most proximal vertebra with psoas over half of its body on coronal T2 STIR sequence. The last lumbar vertebra was named considering both its number and the presence or absence of LSTV according to Castellvi classification. These same parameters were also assessed on 207 PET-CT scans of another cohort including the whole spine.

RESULTS

Proximal insertion of the psoas was L1 in 94.1% of cases: 98.5% in case of modal anatomy, 81.4% in case of LSTV, and 51.7% in case of missing or supernumerary lumbar vertebra without LSTV. There was no statistically significant difference between MRI and CT data. The inter-reader agreement for determination of psoas proximal insertion was excellent (kappa = 0.96).

CONCLUSION

Proximal insertion of the psoas muscle is a helpful marker for correct numbering of the lumbar vertebrae in MRI and to detect a complete lumbosacral segmentation anomaly.

KEY POINTS

• Proximal insertion of the psoas muscle can be easily identified on a coronal T2 STIR sequence. • Psoas proximal insertion on the spine almost always designates the first lumbar vertebra and is helpful to accurately number all lumbar vertebrae, especially in case of lumbosacral transitional vertebra. • Conversely, when psoas muscle does not insert five lumbar bodies above the apparent lumbosacral joint, the probability of variation in the number of lumbar vertebrae is high.

Spinal Enumeration by Morphologic Analysis of Spinal Variants: Comparison to Counting in a Cranial-To-Caudal Manner

Objective

To compare the spinal enumeration methods that establish the first lumbar vertebra in patients with spinal variants.

Materials and Methods

Of the 1446 consecutive patients who had undergone computed tomography of the spine from March 2012 to July 2016, 100 patients (62 men, 38 women; mean age, 47.9 years; age range, 19-88 years) with spinal variants were included. Two radiologists (readers 1 and 2) established the first lumbar vertebra through morphologic analysis of the thoracolumbar junction, and labeled the vertebra by counting in a cranial-to-caudal manner. Inter-observer agreement was established. Additionally, reader 1 detected the 20th vertebra under the assumption that there are 12 thoracic vertebra, and then classified it as a thoracic vertebra, lumbar vertebra, or thoracolumbar transitional vertebra (TLTV), on the basis of morphologic analysis.

Results

The first lumbar vertebra, as established by morphologic analysis, was labeled by each reader as the 21st segment in 65.0% of the patients, as the 20th segment in 31.0%, and as the 19th segment in 4.0%. Inter-observer agreement between the two readers in determining the first lumbar vertebra, based on morphologic analysis, was nearly perfect (κ value: 1.00). The 20th vertebra was morphologically classified as a TLTV in 60.0% of the patients, as the first lumbar segment in 31.0%, as the second lumbar segment in 4.0%, and as a thoracic segment in 5.0%.

Conclusion

The establishment of the first lumbar vertebra using morphologic characteristics of the thoracolumbar junction in patients with spinal variants was consistent with the morphologic traits of vertebral segmentation.

Determination of lumbosacral transitional vertebrae in kidney urinary bladder x-ray films in the Saudi population

OBJECTIVES

To investigated the rate of occurrence of lumbosacral transitional vertebrae (LSTV), spinal variant, in kidney urinary bladder (KUB) plain radiographs in a Saudi population.  Methods: Between January 2012 to January 2015, KUB plain films obtained from patients at King Abdulaziz University Hospital, Jeddah, Saudi Arabia, were reviewed, and the presence or absence of LSTV was documented and classified as incomplete or complete. Patients who had evidence of spinal surgery that would obscure the view were excluded.  Results: A total of 2078 patients underwent KUB examinations during the study period; LSTV anomalies were detected in 158 of these. Sacralization was present in 153 (96.8%) of this cohort, while lumbarization was present in 5 (3.2%). A total of 136 (86.1%) of the sacralized segments were of the incomplete type, whereas 17 (10.7%) were complete. Of the lumbarized vertebrae, 3 (1.8%) were incomplete, and 2 (1.2%) were complete. The most frequent type in men was type Ib (28.5%) for sacralized segments, and type IIb for lumbarized segments (0.6%). In women, type Ia was the most common form of sacralized segments (11.3%) and type IIb was the most common form of lumbarized segments (2.8%). Conclusion: The prevalence of LSTV in Saudi patients is 7.6%, with a higher incidence of sacralization than lumbarization. Further studies with larger sample sizes and longer follow-up time are needed to demonstrate the clinical significance thereof.

Differentiation and classification of thoracolumbar transitional vertebrae

The literature states that transitional vertebrae at any junction are characterized by features retained from two adjacent regions in the vertebral column. Currently, there is no published literature available that describes the prevalence or morphology of thoracolumbar transitional vertebrae (TLTV). The aim of this study was to identify the qualitative characteristics of transitional vertebrae at the thoracolumbar junction and establish a technique to differentiate the various subtypes that may be found. A selection of vertebral columns from skeletal remains (n = 35) were evaluated in this study. Vertebrae were taken based on features that are atypical for vertebrae in each relative region. The transitional vertebrae were qualitatively identified based on overlapping thoracic and lumbar features of vertebrae at the thoracolumbar junction. The following general overlapping characteristics were observed: aplasia or hypoplasia of the transverse process, irregular orientation on the superior articular process and atypical mammillary bodies. The results show that the most frequent location of the transitional vertebrae was in the thoracic region (f = 23). The second most frequent location was in the lumbar region (f = 10). In two specimens of the selection (f = 2), an additional 13th thoracic vertebra was present which functioned as a transitional vertebra. This study concluded that one can accurately identify the characteristics of transitional vertebrae at the thoracolumbar junction. In addition, the various subtypes can be differentiated according to the region in the vertebral column the vertebra is located in and the relative number of vertebral segments in the adjacent regions of the vertebral column. This provides a qualitative tool for researchers to differentiate the transitional vertebrae from distinctly different typical thoracic or lumbar vertebrae at the thoracolumbar junction.

Lumbosacral Transitional Segments: An Interventional Spine Specialist's Practical Approach

The presence of a lumbosacral transitional vertebrae (LSTV) should prompt a more detailed preprocedural evaluation of the vertebral column to accurately determine spinal levels. An LSTV should prompt the use of corroborating intraprocedural imaging to verify morphology. The most important factors in treating lumbosacral transitional segments are communication among treating physicians to ensure segmental enumeration consistency and associated appropriate patient treatment.

Role of Anatomical Landmarks in Identifying Normal and Transitional Vertebra in Lumbar Spine Magnetic Resonance Imaging

Study Design

Retrospective study.

Purpose

Identification of transitional vertebra is important in spine imaging, especially in presurgical planning. Pasted images of the whole spine obtained using high-field magnetic resonance imaging (MRI) are helpful in counting vertebrae and identifying transitional vertebrae. Counting vertebrae and identifying transitional vertebrae is challenging in isolated studies of lumbar spine and in studies conducted in low-field MRI. An incorrect evaluation may lead to wrong-level treatment. Here, we identify the location of different anatomical structures that can help in counting and identifying vertebrae.

Overview of Literature

Many studies have assessed the vertebral segments using various anatomical structures such as costal facets (CF), aortic bifurcation (AB), inferior vena cava confluence (IC), right renal artery (RRA), celiac trunk (CT), superior mesenteric artery root (SR), iliolumbar ligament (ILL) psoas muscle (PM) origin, and conus medullaris. However, none have yielded any consistent results.

Methods

We studied the locations of the anatomical structures CF, AB, IC, RRA, CT, SR, ILL, and PM in patients who underwent whole spine MRI at our department.

Results

In our study, 81.4% patients had normal spinal segmentation, 14.7% had sacralization, and 3.8% had lumbarization. Vascular landmarks had variable origin. There were caudal and cranial shifts with respect to lumbarization and sacralization. In 93.8% of cases in the normal group, ILL emerged from either L5 alone or the adjacent disc. In the sacralization group, ILL was commonly seen in L5. In the lumbarization group, ILL emerged from L5 and the adjacent disc (66.6%). CFs were identified at D12 in 96.9% and 91.7% of patients in the normal and lumbarization groups, respectively. The PM origin was observed from D12 or D12–L1 in most patients in the normal and sacralization groups.

Conclusions

CF, PM, and ILL were good identification markers for D12 and L5, but none were 100% accurate.

A Review of Symptomatic Lumbosacral Transitional Vertebrae: Bertolotti's Syndrome

BACKGROUND

Lumbosacral transitional vertebrae (LSTV) are increasingly recognized as a common anatomical variant associated with altered patterns of degenerative spine changes. This review will focus on the clinical significance of LSTV, disruptions in normal spine biomechanics, imaging techniques, diagnosis, and treatment.

METHODS

A Pubmed search using the specific key words "LSTV," "lumbosacral transitional vertebrae," and "Bertolotti's Syndrome" was performed. The resulting group of manuscripts from our search was evaluated.

RESULTS

LSTV are associated with alterations in biomechanics and anatomy of spinal and paraspinal structures, which have important implications on surgical approaches and techniques. LSTV are often inaccurately detected and classified on standard AP radiographs and MRI. The use of whole-spine images as well as geometric relationships between the sacrum and lumbar vertebra increase accuracy. Uncertainty regarding the cause, clinical significance, and treatment of LSTV persists. Some authors suggest an association between LSTV types II and IV and low back pain. Pseudoarticulation between the transverse process and the sacrum creates a "false joint" susceptible to arthritic changes and osteophyte formation potentially leading to nerve root entrapment. The diagnosis of symptomatic LSTV is considered with appropriate patient history, imaging studies, and diagnostic injections. A positive radionuclide study along with a positive effect from a local injection helps distinguish the transitional vertebra as a significant pain source. Surgical resection is reserved for a subgroup of LSTV patients who fail conservative treatment and whose pain is definitively attributed to the anomalous pseudoarticulation.

CONCLUSIONS

Due to the common finding of low back pain and the wide prevalence of LSTV in the general population, it is essential to differentiate between symptoms originating from an anomalous psuedoarticulation from other potential sources of low back pain. Further studies with larger sample sizes and longer follow-up time would better demonstrate the effectiveness of surgical resection and help guide treatment.

Lumbosacral transitional vertebrae and its prevalence in the Australian population

Study Design Retrospective cohort study. Objective Lumbosacral transitional vertebrae (LSTV) are a common congenital anomaly, and they can be accurately identified on anteroposterior (AP) radiographs of the lumbosacral spine. This study attempts to determine the prevalence of this congenital anomaly and to increase awareness among all clinicians to reduce the risk of surgical and procedural errors in patients with LSTV. Methods A retrospective review of 5,941 AP and lateral lumbar radiographs was performed. Transitional vertebrae were identified and categorized under the Castellvi classification. Results The prevalence of LSTV in the study population was 9.9%. Lumbarized S1 and sacralized L5 were seen in 5.8 and 4.1% of patients, respectively. Conclusion LSTV are a common normal variant and can be a factor in spinal surgery at incorrect levels. It is essential that all clinicians are aware of this common congenital anomaly.

Merits of different anatomical landmarks for correct numbering of the lumbar vertebrae in lumbosacral transitional anomalies

PURPOSE

Anatomical landmarks and their relation to the lumbar vertebrae are well described in subjects with normal spine anatomy, but not for subjects with lumbosacral transitional vertebra (LSTV), in whom correct numbering of the vertebrae is challenging and can lead to wrong-level treatment. The aim of this study was to quantify the value of different anatomical landmarks for correct identification of the lumbar vertebra level in subjects with LSTV.

METHODS

After IRB approval, 71 subjects (57 ± 17 years) with and 62 without LSTV (57 ± 17 years), all with imaging studies that allowed correct numbering of the lumbar vertebrae by counting down from C2 (n = 118) or T1 (n = 15) were included. Commonly used anatomical landmarks (ribs, aortic bifurcation (AB), right renal artery (RRA) and iliac crest height) were documented to determine the ability to correctly number the lumbar vertebrae. Further, a tangent to the top of the iliac crests was drawn on coronal MRI images by two blinded, independent readers and named the 'iliac crest tangent sign'. The sensitivity, specificity and the interreader agreement were calculated.

RESULTS

While the level of the AB and the RRA were found to be unreliable in correct numbering of the lumbar vertebrae in LSTV subjects, the iliac crest tangent sign had a sensitivity and specificity of 81 % and 64-88 %, respectively, with an interreader agreement of k = 0.75.

CONCLUSION

While anatomical landmarks are not always reliable, the 'iliac crest tangent sign' can be used without advanced knowledge in MRI to most accurately number the vertebrae in subjects with LSTV, if only a lumbar spine MRI is available.

Is the iliolumbar ligament a reliable identifier of the L5 vertebra in lumbosacral transitional anomalies?

OBJECTIVE

Sufficiently sized studies to determine the value of the iliolumbar ligament (ILL) as an identifier of the L5 vertebra in cases of a lumbosacral transitional vertebra (LSTV) are lacking.

METHODS

Seventy-one of 770 patients with LSTV (case group) and 62 of 611 subjects without LSTV with confirmed L5 level were included. Two independent radiologists using coronal MR images documented the level(s) of origin of the ILL. The interobserver agreement was analysed using weighted kappa/kappa (wκ/κ) and a Fischer's exact test to assess the value of the ILL as an identifier of the L5 vertebra.

RESULTS

The ILL identified the L5 vertebra by originating solely from L5 in 95 % of the controls; additional origins were observed in 5 %. In the case group, the ILL was able to identify the L5 vertebra by originating solely from L5 in 25-38 %. Partial origin from L5, including origins from other vertebra was observed in 39-59 % and no origin from L5 at all in 15-23 % (wκ = 0.69). Both readers agreed that an ILL was always present and its origin always involved the last lumbar vertebra.

CONCLUSION

The level of the origin of the ILL is unreliable for identification of the L5 vertebra in the setting of an LSTV or segmentation anomalies.

KEY POINTS

• The origin of the ILL is evaluated in subjects with an LSTV. • The origin of the ILL is anatomically highly variable in LSTV. • The ILL is not a reliable landmark of the L5 vertebra in LSTV.

Are spinal or paraspinal anatomic markers helpful for vertebral numbering and diagnosing lumbosacral transitional vertebrae?

Objective

To evaluate the value of spinal and paraspinal anatomic markers in both the diagnosis of lumbosacral transitional vertebrae (LSTVs) and identification of vertebral levels on lumbar MRI.

Materials and Methods

Lumbar MRI from 1049 adult patients were studied. By comparing with the whole-spine localizer, the diagnostic errors in numbering vertebral segments on lumbar MRI were evaluated. The morphology of S1-2 disc, L5 and S1 body, and lumbar spinous processes (SPs) were evaluated by using sagittal MRI. The positions of right renal artery (RRA), superior mesenteric artery, aortic bifurcation (AB) and conus medullaris (CM) were described.

Results

The diagnostic error for evaluation of vertebral segmentation on lumbar MRI alone was 14.1%. In lumbarization, all patients revealed a well-formed S1-2 disc with squared S1 body. A rhombus-shaped L5 body in sacralization and a rectangular-shaped S1 body in lumbarization were found. The L3 had the longest SP. The most common sites of spinal and paraspinal structures were: RRA at L1 body (53.6%) and L1-2 disc (34.1%), superior mesenteric artery at L1 body (55.1%) and T12-L1 disc (31.6%), and AB at L4 body (71.1%). CM had variable locations, changing from the T12-L1 disc to L2 body. They were located at higher sacralization and lower lumbarization.

Conclusion

The spinal morphologic features and locations of the spinal and paraspinal structures on lumbar MRI are not completely reliable for the diagnosis of LSTVs and identification on the vertebral levels.

A reliable measurement for identifying a lumbosacral transitional vertebra with a solid bony bridge on a single-slice midsagittal MRI or plain lateral radiograph

The purpose of this study was to devise a simple but reliable radiological method of identifying a lumbosacral transitional vertebra (LSTV) with a solid bony bridge on sagittal MRI, which could then be applied to a lateral radiograph. The vertical mid-vertebral angle (VMVA) and the vertical anterior vertebral angle (VAVA) of the three most caudal segments of the lumbar spine were measured on MRI and/or on a lateral radiograph in 92 patients with a LSTV and 94 controls, and the differences per segment (Diff-VMVA and Diff-VAVA) were calculated. The Diff-VMVA of the two most caudal vertebrae was significantly higher in the control group (25° (sd 8) than in patients with a LSTV (type 2a+b: 16° (SD 9), type 3a+b: -9° (SD 10), type 4: -5° (SD 7); p < 0.001). A Diff-VMVA of ≤ +10° identified a LSTV with a solid bony bridge (type 3+4) with a sensitivity of 100% and a specificity of 89% on MRI and a sensitivity of 94% and a specificity of 74% on a lateral radiograph. A sensitivity of 100% could be achieved with a cut-off value of 28° for the Diff-VAVA, but with a lower specificity (76%) on MRI than with Diff-VMVA. Using this simple method (Diff-VMVA ≤ +10°), solid bony bridging of the posterior elements of a LSTV, and therefore the first adjacent mobile segment, can be easily identified without the need for additional imaging.

Chiropractic management of a patient with low back pain and Castellvi type II lumbosacral transitional vertebrae

OBJECTIVE

The purpose of this study is to report the chiropractic management of a patient with low back pain and Castellvi type II lumbosacral transitional vertebrae (LSTV).

CLINICAL FEATURES

A patient with previously undiagnosed LSTV presented with moderate low back pain.

INTERVENTIONS AND OUTCOME

Manual therapy, soft tissue therapy, and exercise/stretching were included in the initial treatment plan. Following a short course of treatment, the presenting symptoms resolved; however, they returned after 3 symptom-free months. At that time, radiographs were ordered and the LSTV were identified. Following another course of chiropractic care, the patient's symptoms resolved.

CONCLUSIONS

Chiropractic management resulted in resolution of symptoms for this patient with LSTV.

Lumbosacral transitional vertebra associated with sacral spina bifida occulta: a case report

Congenital malformations such as lumbosacral transitional vertebrae and spina bifida occulta constitute unrare anomalies and could affect the symptomatology of low back pain. A transitional vertebra is characterized by elongation of one or both transverse processes, leading to the appearance ofa sacralized fifth lumbar vertebra or a lumbarized first sacral vertebra. Furthermore, sacral spina bifida occulta is a developmental anomaly that corresponds to the incomplete closure of the vertebral column. In the present case report, we describe a case of a dried sacrum presenting a partially sacralized fifth lumbar vertebra and total spina bifida, extended from first to fifth sacral vertebra. A pseudoarthrosis is formed on the left side and the specimen could be incorporated in Castellvi's type IIa. Moreover, the incidence, morphology, clinical and surgical significance of these spinal malformations are discussed.

Numbering of vertebrae on MRI using a PACS cross-referencing tool

BACKGROUND

For the detection and documentation of numeric variations on spine magnetic resonance imaging (MRI), different techniques have previously been introduced. However, these methods require additional special imaging algorithms, software, or devices. We intend to introduce a vertebral numbering method using the existing picture archiving and communication system (PACS) and MRI system.

PURPOSE

To assess the accuracy of a method for numbering presacral vertebrae based on the cross-referencing of two sagittal MRI series.

MATERIAL AND METHODS

This study was a retrospective review of 224 consecutive patients who underwent both lumbar MRI with cervicothoracic scan and whole spine radiographic examinations. A radiologist and a neurosurgeon independently counted the number of presacral vertebrae in a cranial-to-caudal approach with cross-referencing of cervicothoracic and lumbar MRI sagittal series on the PACS workstation. Radiographic numbering from the cervical through the thoracic to the lumbar vertebrae, as a reference standard, was completed independently by the two reviewers. An analysis of the inter-observer and intermodality agreements of radiography and MRI was done.

RESULTS

In all cases except one, concordant numbering existed between the two modalities of MRI cross-referencing and radiographs combination. Both observers agreed completely, with no inter-observer discordance.

CONCLUSION

The number of vertebrae could be identified consistently by counting caudally from C2 with cross-referencing cervicothoracic and lumbosacral sagittal MRI scans on the PACS workstation.

Partial lumbosacral transitional vertebrae: 2 cases of unilateral sacralization

OBJECTIVE

Lumbosacral transitional vertebrae (LSTV) are relatively common skeletal anomalies with a debated role in low back pain. There are few documented cases of conservative care being used to address LSTV-associated symptomatology. The current report discusses chiropractic management of 2 patients with unilateral sacralization.

CLINICAL FEATURES

Two patients with LSTV involving unilateral sacralization of L5, a Castellvi type IIIa variant, presented with back pain to a chiropractic clinic. Each case presented with symptomatology similar to piriformis syndrome.

INTERVENTION AND OUTCOME

Manual therapy, including spinal manipulation soft tissue therapies and exercise/stretching, was used to address the presenting symptoms. Approximately 2 weeks after initial treatment, the first patient subjectively reported a 70% improvement in symptoms, with lumbar extension increased to full in active range of motion at the lumbar spine but with continued tenderness and hypertonicity at the left piriformis and gluteus medius. After 4 weeks of treatment, the second patient reported improvement in pain and perceived mobility, although prolonged standing remained an aggravating factor. Although both showed improvement, neither case resulted in complete resolution of symptoms.

CONCLUSION

The presenting cases demonstrated partial resolution of symptoms after chiropractic management. It is proposed that sacralization is a possible cause of back pain in these cases.

Variable morphology of the sacrum in a Chinese population

Although several morphological variations of sacrum have been reported in western populations, little attention has been paid to this anatomic issue in eastern people, and classification of sacral variability in particular. In this research of sacral morphology in Chinese people, we investigated and measured thoroughly and systematically 203 specimens of intact dry Chinese adult sacra. Morphological features of sacral variations were observed by visual inspection, and correlation parameters of variability were measured with a vernier caliper. The incidence of sacral variations was calculated. We found that the overall rate of sacral variations was 58.1% (male: 57.4%; female: 59.5%). The anatomical variants that we observed fell into the following five categories: accessory auricular surface (25 specimens, 12.3%); sacral skewness (48 specimens, 23.6%); transitional vertebra (34 specimens, 16.7%); sacral spina bifida occulta (57 specimens, 28.1%), Degrees I, II, and III of which were 36, 14, and 7 specimens, respectively; multiple variations (42 specimens, 20.7%), the types of which were diversified. This study reveals that sacral variations are common in Chinese population. The sacral variants in anatomic morphology should be taken into consideration when diagnosing and treating sacrum-related diseases.

High assimilation of the sacrum in a sample of American skeletons: prevalence, pelvic size, and obstetrical and evolutionary implications

High assimilation sacrum is fusion of the caudal-most lumbar vertebra to the first sacral vertebra. Previous studies have shown that high assimilation is associated with clinical problems, including obstetrical difficulty. This study used adult American males (n = 1,048) and females (n = 1,038) of the Hamann-Todd and Terry skeletal collections to determine the prevalence of high assimilation and its effect on pelvic size, and to consider the obstetrical and evolutionary implications of high assimilation. The prevalence of high assimilation in this sample is 6.3%, with males and females not differing significantly from one another in their prevalence. This prevalence is near the median for that reported in 41 other samples. In both males and females, individuals with high assimilation have significantly longer anteroposterior and posterior sagittal diameters of the inlet, and shorter sacrum compared to those with a nonassimilated sacrum. Females with high assimilation have a significantly narrower sacral angulation (i.e., reduced inclination of ventral axis of sacrum), and shorter posterior sagittal diameter of the outlet compared to those with a nonassimilated sacrum. A short posterior sagittal diameter of the outlet is associated with childbirth difficulty. As high assimilation is partial homeotic transformation of a lumbar vertebra, this study supports previous research that homeotic transformation of vertebrae is selectively disadvantageous.