Clinical assessment and management of Bertolotti Syndrome: a review of the literature

Castellvi classification of lumbosacral transitional vertebrae: comparison between conventional radiography, CT, and MRI

BACKGROUND

The reliability and diagnostic accuracy of commonly used diagnostic imaging modalities in the classification of lumbosacral transitional vertebrae (LSTV) are poorly known, and comparative studies are scarce.

PURPOSE

To compare the diagnostic performance of conventional radiography (CR), computed tomography (CT), and magnetic resonance imaging (MRI) in classifying LSTVs.

MATERIAL AND METHODS

In this retrospective cross-sectional study, a total of 852 patients undergoing lumbar imaging studies using all three modalities were initially assessed for the presence of LSTV using CT scans. In total, 100 patients with LSTV anatomy were identified. Four readers performed blinded and independent evaluations of these 100 patients on each modality, and an experienced fellowship-trained radiologist performed a gold standard read using all three modalities. Inter-reader reliability metrics were analyzed in comparison to the gold standard. Statistical software R (4.2.1) was used for the analyses.

RESULTS

We found superior diagnostic efficacy for CT: the sensitivity, specificity, accuracy, and balanced accuracy were 76%, 93%, 77%, and 84%, respectively. For MRI, the metrics were 54%, 88%, 56%, and 68%, and for CR 32%, 85%, 42%, and 59%, respectively. Inter-reader reliability was found to be good for CT (κ = 0.63-0.71) and fair for both CR (κ = 0.16-0.32) and MRI (κ = 0.24-0.56).

CONCLUSION

CT had the highest diagnostic performance in all measured metrics with good inter-reader reliability. MRI and CR showed fairly poor sensitivity and accuracy, and thus consideration should be used when classifying LSTVs with these two modalities.

The Clinical Significance of Lumbar Transverse Process Lengths Associated with Lumbosacral Transitional Vertebrae: A Landmark for Lumbar Spine Enumeration

OBJECTIVE

This study aimed to identify which lumbar vertebral level above a lumbosacral transitional vertebra (LSTV) demonstrated the longest transverse process (TVP) lengths.

METHODS

In this exploratory quantitative osteological cohort study using a digital Vernier caliper, dried human cadaveric lumbar TVPs were measured for linear horizontal length at each lumbar vertebra, left and right sides. Data collection was conducted in South Africa at the Raymond A. Dart Collection of Modern Human Skeletons and the Pretoria Bone Collection. The LSTV cohort consisted of 110 spinal columns and an LSTV-free control cohort of a sex-balanced randomized selection of 30 male and 30 female spinal columns.

RESULTS

Compared with the control cohort, the LSTV cohort demonstrated longer TVPs for every vertebral level, particularly L3, while the left side demonstrated longer TVPs overall. There were no statistical differences in TVP length within the LSTV cohort when comparing all levels (P > 0.05). The L3 TVPs demonstrated the longest mean lengths in both control (65%) and LSTV (58%) cohorts. The general trend was that the TVPs of L3 had the longest mean length for both the left and the right sides in both cohorts and both sexes.

CONCLUSIONS

In the absence of whole-spine imaging, these findings indicate that L3 TVPs may offer an alternative bony landmark, which may aid in spinal enumeration estimation in the setting of LSTV. This is of value for radiograph appraisal and may aid with correct-level intervention.

Techniques in medicine: ipsilateral transforaminal epidural steroid injection in Bertolotti's syndrome

Bertolotti's syndrome, also known as lumbosacral transitional vertebrae, is a relatively rare spinal condition characterized by an anatomical variation in the lower spine. Conservative approaches such as physical therapy, anti-inflammatory medications and lifestyle modifications may be recommended for mild cases. In more severe cases or when conservative measures fail to provide relief, injections such as may be considered to alleviate pain. This case is unique in that we document a challenging technique of ipsilateral transforaminal epidural steroid injection in a patient with Bertolotti's syndrome.

Influences of lumbo-sacral transitional vertebrae for anterior lumbar interbody fusion

Lumbo-sacral transitional vertebrae (LSTV) are frequent congenital variances of the spine and are associated with increased spinal degeneration. Nevertheless, there is a lack of data whether bony alterations associated with LSTV result in reduced segmental restoration of lordosis when performing ALIF. 58 patients with monosegmental stand-alone ALIF in the spinal segment between the 24th and 25th vertebra (L5/S1)/(L5/L6) where included. Of these, 17 patients had LSTV and were matched to a control population by age and sex. Pelvic incidence, pelvic tilt, sagittal vertical axis, lumbar lordosis, segmental lordosis, disc height and depth were compared. LSTV-patients had a significantly reduced segmental lordosis L4/5 (p = 0.028) and L5/S1/(L5/L6) (p = 0.041) preoperatively. ALIF resulted in a significant increase in segmental lordosis L5/S1 (p < 0.001). Postoperatively, the preoperatively reduced segmental lordosis was no longer significantly different in segments L4/5 (p = 0.349) and L5/S1/(L5/6) (p = 0.576). ALIF is associated with a significant increase in segmental lordosis in the treated segment even in patients with LSTV. Therefore, ALIF is a sufficient intervention for restoring the segmental lordosis in these patients as well.

A rare cause of low back pain in adolescence - Bertolotti syndrome: A case report

Background

Bertolotti syndrome (BS) is defined as a congenital anomaly of the spine that includes sacralization of the lowest lumbar vertebra or lumbarization of the first sacral vertebra (i.e., lumbosacral transitional vertebra- LSTV) and the pain associated with this condition. The incidence of BS in adolescence is rare; we found only three such case reports of patients under the age of 18 in the literature, here will add a fourth.

Case Description

A 17-year-old female presented with a 2-month history of low back pain exacerbated by physical activity. Her neurological examination was normal, except for pain elicited when applying pressure over the sacroiliac joints bilaterally, and over the spinous process of the L5 vertebra. The computed tomography scan documented BS: (i.e., LSTV - Castellvi classification: Type IIa on the left side). She was successfully treated with nonsteroidal anti-inflammatory drugs (NSAIDs) alone.

Conclusion

Here, we report a 17-year-old female who was symptomatic from BS and was successfully treated with NSAIDs.

A systematic review and bibliometric study of Bertolotti's syndrome: clinical characteristics and global trends

PURPOSE

Bertolotti's syndrome is a prevalent congenital deformity. However, many physicians fail to include it in their differential diagnosis for low back pain (LBP), which results in missed diagnosis or misdiagnosis. There is still a lack of standardized treatment and management strategies for Bertolotti's syndrome. This study aimed to review the clinical characteristics and management of Bertolotti's syndrome and reports bibliometric insights in advancements in Bertolotti's syndrome research.

METHODS

Studies published until 30 September 2022 were systematically reviewed according to the PRISMA guidelines. Three independent reviewers extracted the data and assessed the quality and risk of bias of the studies based on the methodological index of non-randomized studies (MINORS). SPSS, VOS viewer, and the Citespace software were used for the systematic review, visual analysis, data mining, mapping, and clustering of the retrieved articles, which presented clear and visual presentations of the structural patterns of published research in graphs.

RESULT

A total of 118 articles, describing a total of 419 patients with Bertolotti's syndrome, were included. There was an upward trend with a steady increase in the number of publications. The world map distribution showed that most publications were predominantly from North America and Asia. The most cited articles were published in the following journals: Spine, J Bone Joint Surg, and Radiology. The mean age of the patients was 47.7 years, and 49.6% of them were male. A total of 159 (96.4%) patients had LBP symptoms. The mean symptom duration was 41.4 months (74.8%), and most of the patients had Castellvi type II. Disc degeneration was the most reported comorbid spinal diseases. The mean methodological index of non-randomized studies score was 4.16±3.95 points (range, 1-21). A total of 265 (68.3%) patients underwent surgical treatments. Minimally invasive surgical techniques, prevalence, image classification, and disc degeneration were the current main research areas of Bertolotti's syndrome.

CONCLUSIONS

The steady increase in the number of publications demonstrated the increased attention of researchers on this topic. Our results showed a significant prevalence of Bertolotti's syndrome in patients with LBP and a long symptom duration before the initiation of treatment. Surgical treatments were commonly used to treat patients with Bertolotti's syndrome after a non-effective conservative treatment. Minimally invasive surgical techniques, prevalence, image classification, and disc degeneration are the major research areas of Bertolotti's syndrome.

Symptom-imaging correlation in lumbar spine pain

Lumbar spine MRI is associated with a high prevalence of morphological abnormalities in both symptomatic and asymptomatic individuals. A difficult challenge, therefore, is distinguishing the relevant findings causing symptoms from incidental findings. The accurate diagnosis of pain generator is important because misdiagnosis can negatively impact patient management and outcome. Spine physicians use clinical symptoms and signs to interpret lumbar spine MRI and make treatment decisions. Symptom-MRI correlation enables the targeted inspection of images for pain generator. Radiologists can also use clinical information to improve diagnostic confidence and the value of dictated reports. Because high-quality clinical information may be difficult to obtain, radiologists often generate lists of lumbar spine abnormalities that are otherwise difficult to rank as pain generators. Based on the literature review, this article attempts to distinguish the MRI abnormalities that may represent incidental findings from the abnormalities that are more commonly associated with lumbar spine-related symptoms.

Prevalence of Lumbosacral Transitional Vertebral Anomalies Among Healthy Volunteers and Patients with Hip Pathology: Association with Spinopelvic Characteristics

A lumbosacral transitional vertebra (LSTV) has been reported to be prevalent among patients with hip dysplasia. The aims of this study were to determine the (1) prevalence of an LSTV in young patients presenting with hip pain and a group of asymptomatic volunteers, (2) effect of an LSTV on spinopelvic characteristics, and (3) presence of low back pain among patients with an LSTV.

Methods

This cross-sectional study included 102 patients with hip pathology and 51 asymptomatic volunteers (mean age, 33.9 ± 7.3 years; mean body mass index, 26.0 ± 5.0 kg/m2; 57.5% female). Participants underwent radiographic assessment of the lumbar spine and pelvis in standing and deep-seated positions. LSTV occurrence was classified according to the Castellvi system. Spinopelvic characteristics included lumbar lordosis (including segmental lumbar angles), pelvic tilt, and hip flexion (pelvic-femoral angle). Differences between standing and deep-seated values were calculated. Low back pain was assessed using the Oswestry Disability Index.

Results

The prevalence of LSTV type ≥II was 8.5%, with no difference between patients and volunteers (p = 0.386). Individuals with an LSTV had a greater standing L1-L5 angle (mean, 51.6° ± 11.7° versus 38.9° ± 9.3°; p < 0.001). The overall spinal flexion (change in L1-S1 angle between the standing and deep-seated positions) in individuals with an LSTV was similar to that in individuals without an LSTV; restricted L5-S1 mobility was compensated for at L1-L2 (10.2° ± 5.8° in those with versus 8.4° ± 4.1° in those without an LSTV; p = 0.070). No significant difference in the presence of low back pain was found (p = 0.250).

Conclusions

An LSTV was found in 8.5% of young adults, with no difference between patients with hip pathology and controls. Individuals with an LSTV have greater standing lumbar lordosis, with altered mechanics at the cephalad adjacent level, which may predispose these individuals to degenerative changes at this level.

Level of Evidence

Prognostic Level II. See Instructions for Authors for a complete description of levels of evidence.

Endoscopic Resection of Pseudoarticulation as a Treatment for Bertolotti's Syndrome

Bertolotti's syndrome is described as lower back pain with the presence of lumbosacral transitional vertebrae (LSTV) associated with an articulation, pseudoarticulation, or full fusion of the transverse process to the sacrum and ilium. We present a unique case of the management of a 57-year-old woman with treatment-resistant lower back pain who underwent endoscopic resection of a pseudoarticulation related to LSTV. The patient underwent multiple treatment regimens without achieving satisfactory relief. These included physical therapy, sacroiliac (SI) joint injections, radiofrequency lesioning at multiple levels, and spinal cord stimulator placement. Relief with injection at the patient's pseudoarticulation confirmed this as a contributor to the patient's back pain. Interventional management of Bertolotti's syndrome can include different modalities, most recently including minimally invasive surgical techniques. This patient experienced partial relief of lower back pain after undergoing minimally invasive resection of the pseudoarticulation. This case demonstrates the benefit of a minimally invasive resection of this anatomic abnormality in a patient who has undergone previous treatments. Isolating this anomaly as a source of pain is necessary to ensure a favorable response and prevent needless surgery.

Lumbosacral transitional vertebrae alter the distribution of lumbar mobility–Preliminary results of a radiographic evaluation

Background

Lumbo-sacral transitional vertebrae (LSTV) are one of the most common congenital variances of the spine. They are associated with an increased frequency of degeneration in the cranial adjacent segment. Hypermobility and concomitant increased loads are discussed as a possible reason for segmental degeneration. We therefore examined the lumbar and segmental motion distribution in patients with LSTV with flexion-extension radiographs.

Methods

A retrospective study of 51 patients with osteochondrosis L5/S1 with flexion and extension radiographs was performed. Of these, 17 patients had LSTV and were matched 1:1 for age and sex with patients without LSTV out of the collective of the remaining 34 patients. The lumbar and segmental range of motion (RoM) by segmental lordosis angle and the segmental wedge angle were determined. Normal distribution of parameters was observed by Kolmogorov-Smirnov-test. Parametric data were compared by paired T-test. Non-parametric data were compared by Wilcoxon-rank-sum-test. Correlations were observed using Spearman’s Rank correlation coefficient. A p-value <0.05 was stated as statistically significant.

Results

Patients with LSTV had mean age of 52.2±10.9, control group of 48.9±10.3. Both groups included 7 females and 10 males. Patients with LSTV presented with reduced RoM of the lumbar spine (LSTV 37.3°±19.2°, control 52.1°±20.5°, p = 0.065), however effects were statistically insignificant. LSTV significantly decreased segmental RoM in the transitional segment (LSTV 1.8°±2.7°, control 6.7°±6.0°, p = 0.003). Lumbar motion distribution differed significantly; while RoM was decreased in the transitional segment, (LSTV 5.7%, control 16.2%, p = 0.002), the distribution of lumbar motion to the cranial adjacent segment was increased (LSTV 30.7%, control 21.6%, p = 0.007).

Conclusion

Patients with LSTV show a reduced RoM in the transitional segment and a significantly increased motion distribution to the cranial adjacent segment in flexion-extension radiographs. The increased proportion of mobility in the cranial adjacent segment possibly explain the higher rates of degeneration within the segment.

Operative Treatment of Bertolotti Syndrome: Resection Versus Fusion

OBJECTIVE

To compare the outcomes of joint resection versus fusion in patients who undergo operative treatment for Bertolotti syndrome.

METHODS

A chart review identified patients with Bertolotti syndrome who underwent operative treatment, consisting of either Bertolotti joint decompression/resection or fusion across the abnormal transitional lumbosacral vertebrae. Patients with other symptomatic operative spinal disease were excluded.

RESULTS

Twenty-seven patients (9 men, 18 women) were identified for inclusion in the study with an average age of 40 ± 16 years, body mass index of 27 ± 5, and follow-up of 39 ± 48 months. Most patients presented with back pain (74%) or leg pain (48%) for an average duration of 61 ± 54 months. Nineteen (70%) presented with a Castellvi subtype 2a Bertolotti joint with computed tomography as the most common method for radiographic diagnosis (56%). When comparing long-term pain improvement (>12 months) after fusion (n = 9) versus joint resection (n = 18), more fusion patients reported improvement in their pain (78%) compared to joint resection (28%, P = 0.037). There was not a statistically significant difference in the short-term pain improvement (<6 months) between the fusion (100%) and resection (78%) patients (P = 0.27). There was no statistically significant difference between the two groups in terms of age, sex, body mass index, presenting symptoms, symptom duration, Bertolotti injection response, follow up, Castellvi subtype, and complications.

CONCLUSIONS

Patients with Bertolotti syndrome who underwent surgical fusion across the transitional lumbosacral vertebrae had a higher rate of long-term pain improvement compared to patients who had resection of the abnormal pseudoarticulation.

Identifying the relationship between lumbar sacralization and adjacent ligamentous anatomy in patients with Bertolotti syndrome and healthy controls

OBJECTIVE

Bertolotti syndrome is a diagnosis given to patients experiencing low-back pain due to a lumbosacral transitional vertebra (LSTV). LSTVs cause altered biomechanics at the lumbosacral junction, predisposing these patients to degenerative disease. It has been proposed that these patients have additional non-osseous variation such as ligamentous differences in the lumbar spine. The iliolumbar ligament, which attaches from the iliac crest to the transverse process of L4 and L5, plays a significant role in reducing lumbar motion in all six degrees of freedom; therefore, altered ligament anatomy can have a significant impact on stability. The purpose of this study was to examine the iliolumbar ligament complex in patients with Bertolotti syndrome and anatomically normal controls to determine if underdevelopment of the iliolumbar ligament complex is seen in Bertolotti syndrome.

METHODS

This is a retrospective analysis of patients with Bertolotti syndrome and anatomically normal controls who received care at the authors' institution between 2010 and 2020. Axial thickness of the iliolumbar ligament at the L5 vertebral level was assessed via MRI. Results were compared between the defective and normal side within unilaterally affected (Castellvi types IIa and IIIa) Bertolotti syndrome patients, between defective sides in bilaterally affected Bertolotti syndrome patients (Castellvi types IIb, IIIb, and IV), and between the affected side in Bertolotti syndrome patients and the corresponding location in normal controls.

RESULTS

A total of 173 patients were included in the study, 102 with Bertolotti syndrome and 71 controls. Among the Bertolotti patients, 49 had left LSTVs, 29 had right LSTVs, and 24 had bilateral LSTVs. For patients with unilateral defects, defective side ligaments were thinner than ligaments on the normal side (p < 0.05). For bilateral LSTVs, ligament thickness on each side was considered statistically equivalent (p < 0.05) and not significantly different from that in controls.

CONCLUSIONS

Bertolotti syndrome correlates to significant underdevelopment of the iliolumbar ligament corresponding to the side of the LSTV as compared to the ligament on the contralateral side. In patients with bilateral LSTVs, no difference in the iliolumbar ligament compared to that in controls was seen. Developmental changes in the iliolumbar ligament may further exacerbate the altered lumbosacral biomechanics seen in patients with unilateral LSTV, whereas bilateral LSTVs may still allow normal development of the ligament complex. Further research should be done to examine the discrepancies seen in this study.

Surgical interventions for Bertolotti's syndrome: case report and review of unsatisfactory cases in the literature

Background

Bertolotti’s syndrome (BS) is characterized by the enlargement of transverse processes in caudal lumbar segments, causing chronic and persistent low back pain or sciatica. The present study aimed to describe our surgical technique for BS treatment and to review existing literature describing unsatisfactory outcomes.

Case presentation

We report a patient who complained of lower back pain and soreness that intermittently radiated to his left leg for longer than 10 years. Based on an examination of his symptoms and signs, including imaging and electrical physiology assessments, in addition to the report of temporary pain relief after a local steroid injection to a diagnostic trigger site (articulation between the transverse process and the sacral ala or iliac crest), the patient was diagnosed with BS. The applied surgical techniques included minimally invasive, three-dimensional C-arm guidance, a tubing approach, and microscopic and bone cavitron ultrasonic surgical aspirator–assisted operations. After surgery, improvements were reported on the visual analog scale (from 8 to 2 points on a 10-point scale) and the straight leg raising test for the left leg (20° to 90°) within 3 days. The patient gained an ordinary life and returned to work within one week of surgery, with no observed postoperative complications.

Conclusions

Minimally invasive tubular microscopic decompression and disarticulation is an effective method for treating BS. However, to achieve a successful outcome, it is recommended to use physician-proficient techniques that are in line with the patient’s diagnosis.

Pediatric Back Pain Associated with Bertolotti Syndrome: A Report of 3 Cases with Varying Treatment Strategies

CASE

Three pediatric patients with back pain associated with Bertolotti syndrome are presented. After failing conservative management, 1 patient underwent mega-apophysis resection, another underwent resection with decompression, and the final underwent posterior fusion. All patients had complete resolution of back pain and returned to full activity at final follow-up.

CONCLUSION

Lumbosacral transitional vertebrae are congenital anomalies spanning a spectrum from partial/complete L5 sacralization to partial/complete S1 lumbarization with varying clinical presentations. Identification of variable anatomy and symptoms guides surgical management. We present 3 cases with differing surgical techniques including pseudoarticulation resection, arthrodesis of the involved levels, and neuroforaminal decompression.

A case of Bertolotti's syndrome as a cause of sciatica

Background:

Bertolotti’s syndrome (i.e., varying extent of fusion between the last lumbar vertebra and the first sacral segment) or lumbosacral transitional vertebrae is a rare cause of back pain. Notably, this syndrome is one of the differential diagnoses for patients with refractory back pain/sciatica.

Case Description:

A 71-year-old male presented with low back pain of 3 years duration that radiated into the right lower extremity resulting in numbness in the L5 distribution. He then underwent a minimally invasive approach to resect the L5 “wide” transverse process following the CT diagnosis of Bertolotti’s syndrome. Prior to surgery, patient reported pain that was exacerbated by ambulation that resolved post-operative.

Conclusion:

Bertolotti’s syndrome is one of the rare causes of sciatica that often goes undiagnosed. Nevertheless, it should be ruled out for patients with back pain without disc herniations or other focal pathology diagnosed on lumbar MR scans.