Morphological Variations of Sacrum in Adult Indian Population

Introduction: The sacrum is considered as a highly variable bone. Several morphological variations have been documented which exhibit differences in the frequency of occurrence and morphological characteristics in various study populations. Variant anatomy of the sacrum may be associated with backache, enuresis, neurological anomalies of the lower limb and functional disorders of lower urinary tract. Purpose: The purpose of this study was to identify and describe morphological variations of sacrum in Indian population and enable comparison with different populations. Materials and Methods: The study was conducted on 108 dry adult human sacra and morphological characteristics and variations were noted. Results: Sacral skewness was observed in 7.4% sacra with right sided skewness being predominant. The presence of accessory auricular surface (AAS) was noted in 13% sacra which was at the level of S3 vertebra in most sacra. Spina bifida (SB) was observed in 11.1% sacra and it was most commonly located at S1 vertebral level. Furthermore, the lumbo-sacral transitional vertebra (TV) was documented in 10.2% sacra. Conclusions: Sacrum displays numerous variations in Indian population such as skewness, AAS, SB and TV. Thorough knowledge of morphological characteristics and variations of sacrum is vital and should be contemplated during diagnosis and treatment of sacrum-related diseases.

Osteological Study To Relate Auricular Surface Extent In Sacrum With Prevalence Of Lumbosacral Transitional Vertebra

Introduction: Lumbosacral transitional vertebra (LSTV) is one of recognized morphological variant associatedwith back pain. As sacrum has very crucial role in weight transmission via sacroiliac joint, any change inmorphology of auricular surface of sacrum should have impact in morphology of lumbosacral region.Aim: To study relation between the variable extent of auricular surface in Sacrum and prevalence of LumbosacralTransitional Vertebra (LSTV) along with changes in morphological index.Materials and Methods: Present study was done by taking total 40 adult dry human sacra of both sexes whichwere collected from the Department of Anatomy at Himalayan Institute of Medical Sciences, SRHU, Dehradun. Allsacra were initially divided into two sacral groups of normal sacra and atypical sacra based on absence andpresence of any type of lumbosacral transitional vertebra (LSTV) respectively. Further each group subcategorizedinto three, namely A (normal sacra), B (high sacra) and C (low sacra) based on extend of auricular surface. Metrictraits like maximum auricular length, maximum sacral length, maximum sacral width and sacral index weremeasured and compared.Result: In this study sacra with higher type of auricular surface were found to be associated with more incidenceof sacralization whereas sacra with lower type of auricular surface were associated with lumbarization. Therewas significant difference noticed in mean sacral index of these two sacral groups. Sacral index in sacral groupwith LSTV (Mean 95.06) was found to be less on comparing with sacral group without LSTV (Mean 108.20).Increased mean maximum sacral length (mean 109.62) seen in sacral group with LSTV without significantchange in maximum sacral width (mean 103.75) which can be due to shift of weight transmission axis from lowersacral vertebrae to higher vertebrae.Conclusion: Variable extents of auricular surface of sacrum are associated with variant of lumbosacral transitionvertebra due to change in biomechanics of weight transmission. Thus this study may be helpful to clinicians topredict and treat root cause of LSTV associated back pain.

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.

Lumbosacral Transition Vertebra: Prevalence and Its Significance

STUDY DESIGN: Retrospective analysis of radiological images. PURPOSE: To determine the prevalence of lumbosacral transition vertebra (LSTV) and to study its significance with respect to clinically significant spinal symptoms, disc degeneration and herniation. OVERVIEW OF LITERATURE: LSTV is the most common congenital anomaly of the lumbosacral spine. The prevalence has been debated to vary between 7% and 30%, and its relationship to back pain, disc degeneration and herniation has also not been established. METHODS: The study involved examining the radiological images of 3 groups of patients. Group A consisted of kidney urinary bladder (KUB) X-rays of patients attending urology outpatient clinic. Group B consisted of X-rays with or without magnetic resonance images (MRIs) of patients at-tending a spine outpatient clinic, and group C consisted of X-rays and MRI of patients who had undergone surgery for lumbar disc herniation. One thousand patients meeting the inclusion criteria were selected to be in each group. LSTV was classified by Castellvi's classification and disc degeneration was assessed by Pfirrmann's grading on MRI scans. RESULTS: The prevalence of LSTV among urology outpatients, spine outpatients and discectomy patients was 8.1%, 14%, and 16.9% respectively. LSTV patients showed a higher Pfirrmann's grade of degeneration of the last mobile disc. Results were found to be significant statistically. CONCLUSIONS: The prevalence of LSTV in spinal outpatients and discectomy patients was significantly higher as compared to those attending the urology outpatient clinic. There was a definite causal relationship between the transitional vertebra and the degeneration of the disc immediately cephalad to it.

Anterior Dislodgement of a Fusion Cage after Transforaminal Lumbar Interbody Fusion for the Treatment of Isthmic Spondylolisthesis

Transforaminal lumbar interbody fusion (TLIF) is commonly used procedure for spinal fusion. However, there are no reports describing anterior cage dislodgement after surgery. This report is a rare case of anterior dislodgement of fusion cage after TLIF for the treatment of isthmic spondylolisthesis with lumbosacral transitional vertebra (LSTV). A 51-year-old man underwent TLIF at L4-5 with posterior instrumentation for the treatment of grade 1 isthmic spondylolisthesis with LSTV. At 7 weeks postoperatively, imaging studies demonstrated that banana-shaped cage migrated anteriorly and anterolisthesis recurred at the index level with pseudoarthrosis. The cage was removed and exchanged by new cage through anterior approach, and screws were replaced with larger size ones and cement augmentation was added. At postoperative 2 days of revision surgery, computed tomography (CT) showed fracture on lateral pedicle and body wall of L5 vertebra. He underwent surgery again for paraspinal decompression at L4-5 and extension of instrumentation to S1 vertebra. His back and leg pains improved significantly after final revision surgery and symptom relief was maintained during follow-up period. At 6 months follow-up, CT images showed solid fusion at L4-5 level. Careful cage selection for TLIF must be done for treatment of spondylolisthesis accompanied with deformed LSTV, especially when reduction will be attempted. Banana-shaped cage should be positioned anteriorly, but anterior dislodgement of cage and reduction failure may occur in case of a highly unstable spine. Revision surgery for the treatment of an anteriorly dislodged cage may be effectively performed using an anterior approach.

Lumbosacral transitional vertebrae: a case report and clinical implications / Vértebras lumbosacras de transición: reporte de un caso e implicancias clínicas

A lumbosacral transitional vertebra is a rare congenital anomaly which occurs because of defect in the segmentation of the lumbosacral spine during development. During routine osteology classes for the medical students at the Kasturba Medical College, Mangalore, India, one of the sacra showed the fusion of the fifth lumbar vertebra with the sacrum. The specimen showed an incomplete fusion (sacralization) on the left side and the transverse process was of the large butterfly shape, while on the right it was about the usual size. Though this variation is well known, the details of this anomaly are rarely reported in the anatomical literature. Since there is a strong relationship between the lumbosacral transitional vertebrae and low back pain, this anomaly has gotten increased clinical interest. So this case was studied in detail with relevant review of literature and its surgical, radiological implications are discussed.

Una vértebra de transición lumbosacra es una anomalía congénita rara que se produce debido a defectos en la segmentación de la columna lumbosacra durante el desarrollo. Durante una clase de osteología para estudiantes de medicina en Kasturba Medical College, Mangalore, India, una de las regiones sacras mostró fusión de la quinta vértebra lumbar con el sacro. El especimen mostró fusión incompleta (sacralización) en el lado izquierdo y el proceso transverso tenía forma de mariposa grande, mientras que en el derecho se observó de tamaño normal. A pesar que esta variación es conocida, los detalles de esta anomalía rara vez son reportados en la literatura anatómica. Puesto que existe una fuerte relación entre las vértebras de transición lumbosacra y el dolor de espalda baja, esta anomalía tiene gran interés clínico. Este caso fue estudiado en detalle con la revisión pertinente de la literatura, y son discutidas sus implicancias quirúrgicas y radiológicas.

Far-out Stenosis by the Lumbosacral Transitional Vertebrae / 대한정형외과학회잡지

Surgeons still have many different views on the clinical significances of the lumbosacral transitional vertebrae as one of the causes of chronic low back pain and a higher incidence of adjacent disc degeneration. Moreover, in rare case reports, compression of the exiting nerve root due to abnormal articulation between the hypertrophied transverse process and the sacral ala has been proposed as one of the reasons for the far-out lumbosacral stenosis. Anterior or posterior surgical decompression is recommended in the cases that are refractory to conservative treatment. We reviewed the related literatures and report on a case that suffered from the far-out stenosis due to lumbosacral transitional vertebra and this was successfully treated by decompression using the posterolateral approach.

Manejo quirúrgico del síndrome de Bertolotti: a propósito de un caso / Surgical management of the Bertolotti´s syndrome: case report

We present the case of a 31 year-old man with a story of chronic low back pain in the presence of a transitional lumbosacral vertebra with transverse mega apophysis articulating with the sacrum (Bertolotti´s syndrome). After unsuccessful conservative treatment, an anesthetic blockade in the transverse process and sacral ala joint was performed with complete but brief relief of pain. For that reason, a resection of the transverse process was performed. There is no agreement in the relationship between back pain and the presence of a mega-apophysis. Therefore, surgical treatment of this condition is even more controversial. In the absence of other pain generators, the known biomechanical dysfunction of lumbosacral transitional vertebra in conjunction with a positive injection test lead us to consider surgical resection of the mega-apophysis as an alternative treatment in refractory low back pain. The proven biomechanical alteration of lumbosacral transitional junction and the systematic searching of sources of pain through anesthetic blocks allows that in cases of refractory pain surgical treatment of the mega-apophysis can be an effective alternative.

Presentamos el caso de un paciente varón de 31 años con historia de dolor lumbar crónico mecánico portador de una anomalía de transición lumbosacra con mega-apófisis transversa articulada al ala sacra. El paciente luego de varios tratamientos médicos fallidos fue sometido a bloqueo anestésico de la pseudo articulación transverso sacra con alivio completo pero pasajero de su dolor. Finalmente, se realiza una resección de la mega apófisis con buenos resultados a corto y largo plazo. La relación entre dolor lumbar y la presencia de una mega-apófisis es controvertido. De igual forma el tratamiento quirúrgico consistente en resección de la mega-apófisis es más controvertido aún. La probada alteración biomecánica del segmento lumbosacro transicional junto al descarte sistemático de otras fuentes de dolor y la confirmación diagnóstica mediante bloqueos anestésicos permite plantear que en casos de dolor refractario a tratamiento conservador la resección de la mega-apófisis puede ser una alternativa eficaz.

Lumbar Interbody Metal Cages with Pedicle Screw Fixation in Spondylolisthesis

OBJECTIVE: For lumbar spondylolisthesis, various spinal operation methods have been used to relieve clinical symptoms and to stabilize the spine. To determine the effectiveness of the lumbar interbody metal cages and pedicle screw fixation in patients with spondylolisthesis, the authors retrospectively reviewed 70 patients under-going surgery, and also analyzed the relationship between post-operative clinical improvement and bony fusion, postoperative reduction, as well as transitional vertebrae. METHODS: The authors performed the lumbar interbody metal cages and pedicle screw fixation in 70 consecutive patients suffering from spondylolisthesis between November 1994 and December 1997. Follow-up averaged 18 months(range, 3 to 39 months). The post-operative clinical outcome was expressed as good, fair, or poor. The bony fusion was determined by post-operative simple X-ray films. RESULTS: Of 70 patients with clinical, radiologically unstable spondylolisthesis, the clinical results were good and fair in 92% of the patients, and radiological bony fusion were occurred in 86%. There was the significant relationship between clinical improvement and bony fusion. But there was no significant relationship between clinical improvement and post-operative reduction as well as transitional vertebrae. The post-operative complications occurred in 4% of patients and reoperation was required in 1 patient. CONCLUSION: This study demonstrates that the lumbar interbody cage with pedicle screw fixation is the effective operation method in the treatment of spondylolisthesis, though it demands more difficulties technically.

The Role of Transitional Vertebra in Spondylolysis and Spondyloytic Spondylolisthesis / 대한정형외과학회잡지

Transitional vertebrae include lumbarization and sacralization of lumbosacral region. The prevalence of transitional vertebra was reported as 3 to 21%. It is known that transitional vertebra is related to herniated nucleus pulposus and spinal stenosis but there is no report in English literature about the relationship of transitional vertebra to spondylolysis or spondylolytic spondylolisthesis. The purpose of this study is to evaluate the relationship of transitional vertebra to spondylolysis or spondylolytic spondylolisthesis and to find out the clinical relevance for the treatment. The cases included 182 cases of spondylolysis or spondylolytic spondylolisthesis who were treated at Severance hospital from 1987 to 1993. There were 33 cases of transitional vetebra; 12 lumbarization and 21 sacralization. And there were remaining 149 cases of control group. The degree of anterior sippage was measured by Meyerding's grading and percentage of Taillard method. As the results, the degree of average anterior slippage of L4 was 14.5% in the cases of isthmic defect in L4 and sacralization. The average slippage of L4 was 11.4% in the control group. The degree of average anterior slippage of L5 was 12.5% in the cases of isthmic defect in L5 and lumbarization, and 9.5% in the cases of isthmic defect in L5 and sacralization. The average slippage of L5 was 16.2% in the control group. In summary and conclusion, the cases with isthmic defect in L4 and sacralization showed more anterior slippage than the cases with isthmic defect in L4 without transitional vertebrae, and the cases with isthmic defect in L5 and sacralization showed less anterior slippage than the cases with isthmic defect in L5 without transitional vertebrae. It is concluded that more aggressive treatment is recommended in the cases of isthmic defect in L4 and sacralization, whereas more conservative treatment is recommended in the cases of isthmic defect in L5 and sacralization.