Lumbar Bodies Research Articles

Deep Learning-Based Automated Quality Assurance for Palliative Spinal Treatment Planning in Radiotherapy

Robustquality assurance (QA) for palliative spine radiation therapy (RT) remains critical due to the risk of wrong anatomic level treatment on account of human error in enumerating vertebral bodies accurately based on morphology with incomplete imaging of the spine and prevalence of anatomic variants (10%). We propose a rapid, fully automated deep learning-based QA (DL-QA) tool for segmenting and enumerating vertebral structures from image data, capable of identifying misalignment based on discrepancies in calculated dose coverage. Ina retrospective cohort of 514 patients who received palliative spine radiation treatment at a single institution for spinal metastases, vertebral volumes for each individual spine level were automatically segmented on RT planning computed tomography scans using a publicly available deep learning algorithm, Total Segmentator (TS) deployed in the treatment planning system (Wasserthal et al, 2022). Departmental policy requires that the prescription/plan name include all spinal levels that receive a prescribed dosimetric threshold of V50% > 50%. By comparing the intended spine level target in the prescription and plan name against the TS volumes, the DL-QA flagged all cases for which any target vertebrae did not receive this threshold dose and/or any non-targeted vertebrae that received V50% > 50%. To detect spine anomalies, cases were also flagged if any vertebrae volume was not within ±1σ of the entire population of vertebrae volumes. Flagged cases were either categorized as: (1) wrong spine level RT error; (2) documentation error, in which treatment was correct but the prescription/plan name did not follow Departmental policy; or (3) potential spinal geometric error. All flagged cases were verified manually by checking the original images and treatment planning data. Outof 514 patients, 29 cases were flagged as potential errors. Manual review revealed that one of these was a previously discovered true treatment error (due to anatomic variant with 4 lumbar bodies) while 10 were treated as intended but showed documentation errors due to variants in the number of vertebral bodies, kyphosis of the spine causing non-targeted vertebrae to appear in the treatment field, or improper observation of the Departmental plan naming policy. The remaining 18 cases were associated with flagged vertebrae volumes. Reviewing those patients, we identified spinal anomalies where TS attempted to account for extra or missing vertebrae (N = 9) and cases where TS made segmentation errors (N = 9). Theproposed automated DL-QA system successfully identified patients with spine anomalies, flagged documentation errors, verified the correct target levels of spine RT treatments, and detected a known misadministration. The next phase will involve prospective testing of the system in a clinical setting upstream of treatment delivery.

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

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). 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. 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). 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. • 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.

SURGICAL TREATMENT OF THORACIC AND LUMBAR SPINE FRACTURES USING TRANSPEDICULAR VERTEBROPLASTY AND FIXATION

Objective. To analyze treatment results in patients with fractures of thoracic and lumbar vertebal bodies after transpedicular vertebroplasty and fixation through minimally invasive percutaneous and open approaches. Material and Methods . A total of 154 patients with uncomplicated type A2, A3 fractures of the thoracic and lumbar vertebral bodies were operated on. All patients were examined with X-ray densitometry, spondylography, and CT. Group 1 included 53 patients who underwent vertebroplasty with deproteinized bone graft and percutaneous transpedicular fixation. Patients of Group 2 (n = 41), Group 3 (n = 43) and Group 4 (n = 17) underwent open transpedicular fixation and vertebroplasty with deproteinized bone graft (Group 2) and titanium nikilide granules (Groups 3 and 4). Results . Intraoperative blood loss during open vertebroplasty combined with short-segment transpedicular fixation exceeded that during percutaneous vertebroplasty. Parameters of kyphotic deformity, the wedge index and the loss of correction did not differ significantly except for Group 4. Significant improvement in ODI and VAS scores was noted after percutaneous vertebroplasty as compared with control groups. Conclusion . Transpedicular verteboplasty and transpedicular fixation, both open and percutaneous, performed for the treatment of type A2 and A3 spinal fractures provide reliable stabilization of the injured spinal segments, allow vertebral body height restoration to a greater extent and correction of the kyphotic deformity.

Percutaneous vertebroplasty for senior patients with varying grades of osteoporotic vertebral compression fracture

Objective To investigate therapeutic effects of percutaneous vertebroplasty (PVP) in treatment of varying grades of osteoporotic vertebral compression fracture (OVCF). Methods From January 2004 to October 2010,208 senior OVCF patients were treated by PVP in our department.They were 72 men and 136 women,aged from 70 to 96 years (average,77.8).A total of 242 vertebral bodies were affected,including 134 thoracic and 108 lumbar ones.The fracture and its severity were evaluated according to Genant's semi-quantitative visual method,with OVCF grades Ⅰ, Ⅱ and Ⅲ respectively corresponding to a compression ratio of less than 25％,25％ to 50％ and greater than 50％.The patients were examined postoperation to analyze the ratio of vertebral compression,stability of vertebral body,pain relief and leakage of bone cement. Results All patients in this series were followed up from 6 to 84 months (average,30.5months).The mean cement volumes for thoracic and lumbar bodies were respectively 2.6 ± 0.6 mL and 4.8 ±0.4 mL.The preoperative vertebral compression rate and cobb angle in patients with OVCF grades Ⅱ and Ⅲ were significantly improved postoperation ( P ＜ 0.05) except in the patients with OVCF grade Ⅰ ( P ＞ 0.05).There was no significant difference in pain relief among patients with OVCF grades Ⅰ,Ⅱ and Ⅲ (x2 =0.955,P ＞0.05).The rates of cement leakage were 3.2％ (1/31),10.3％ (15/145) and 25.8％ (17/66) for OVCF grades Ⅰ,Ⅱ and Ⅲ,respectively,but the leakage did not cause clinical symptoms in all patients.The complication rates for OVCFgrades Ⅰ,Ⅱand Ⅲ were respectively 6.5％ (2/31),6.9％ (10/145) and 22.7％ (15/ 66). Conclusions In treatment of varying grades of OVCF,PVP may not make a difference in pain relief,but with increasing OVCF severity it will achieve poorer therapeutic outcomes regarding recovery of vertebral compression and Cobb angle.It is suggested that PVP must be performed for patients with early 0VCF to avoid further vertebral compression. Key words: Spine; Vertebroplasty; Osteoporosis; Fracture, compression

Trabecular bone density of male human cervical and lumbar vertebrae

The objective of this study was to determine the bone mineral density (BMD) of cervical vertebrae and correlate with the lumbar spine. Fifty-seven young adult healthy male volunteers, ranging from 18 to 41 years of age, underwent quantitative computed tomography (QCT) scanning of C2-T1 and L2–L4 vertebrae. To account for correlations, repeated measures techniques were used to compare data as a function of spinal level and region. Linear regression methods were used (±95% CI) to compare data as a function of spinal level and region. The mean age and body height were 25.0 ± 5.8 years and 181.0 ± 7.6 cm. BMD decreased from the rostral to caudal direction along the spinal column. Grouped data indicated that the neck is the densest followed by the first thoracic vertebra and low back with mean BMD of 256.0 ± 48.1, 194.3 ± 44.2, and 172.2 ± 28.4 mg/cm 3, respectively; differences were statistically significant. While BMD did not vary significantly between the three lumbar bodies, neck vertebrae demonstrated significant trends. The matrix of correlation coefficients between BMD and spinal level indicated that the relationship is strong in the lumbar ( r = 0.92–0.96) and cervical ( r = 0.73–0.92) spines. Data from the present study show that the trabecular bony architecture of the neck is significantly different from the low back. These quantitative BMD data from a controlled young adult healthy human male volunteer population may be valuable in establishing normative data specifically for the neck. From a trabecular bone density perspective, these results indicate that lumbar vertebrae cannot act as the best surrogates for neck vertebrae. Significant variations in densities among neck vertebrae, unlike the low back counterpart, may underscore the need to treat these bones as different structures.

Prenatal Development of the Normal Human Vertebral Corpora in Different Segments of the Spine

Vertebral columns from 13 normal human fetuses (10-24 weeks of gestation) that had aborted spontaneously were investigated as part of the legal autopsy procedure. The investigation included spinal cord analysis. To analyze the formation of the normal human vertebral corpora along the spine, including the early location and disappearance of the notochord. Reference material on the development of the normal human vertebral corpora is needed for interpretation of published observations on prenatal malformations in the spine, which include observations of various types of malformation (anencephaly, spina bifida) and various genotypes (trisomy 18, 21 and 13, as well as triploidy). The vertebral columns were studied by using radiography (Faxitron X-ray apparatus, Faxitron Model 43,855, Hewlett Packard) in lateral, frontal, and axial views and histology (decalcification, followed by toluidine blue and alcian blue staining) in and axial view. Immunohistochemical marking with Keratin Wide Spectrum also was done. Notochordal tissue (positive on marking with Keratin Wide Spectrum [DAKO, Denmark]) was located anterior to the cartilaginous body center in the youngest fetuses. The process of disintegration of the notochord and the morphology of the osseous vertebral corpora in the lumbosacral, thoracic, and cervical segments are described. Marked differences appeared in axial views, which were verified on horizontal histologic sections. Also, the increase in size was different in the different segments, being most pronounced in the thoracic and upper lumbar bodies. The lower thoracic bodies were the first to ossify. The morphologic changes observed by radiography were verified histologically. In this study, normal prenatal standards were established for the early development of the vertebral column. These standards can be used in the future--for evaluation of pathologic deviations in the human vertebral column in the second trimester.

Respiratory gas pressures in the spine. Measurements in goats.

Normal values of pO2, pCO2, pH, and intraosseous pressure were measured in situ in the lumbar spine of goats. In the lumbar bodies and discs no difference existed between values found cranially and caudally. pO2 was lower and pCO2 higher in the nucleus pulposus than in the adjacent lumbar bodies. This emphasizes the nutritional route to the disc via the vertebral end plate. Intraosseous pressures in the cranial and caudal levels of the lumbar spine did not differ, and the pressures were the same as otherwise found in cancellous bone. These are the first combined in situ measurements of several basic metabolic parameters in the normal spine using recordings with continuous mass spectrometry. They may constitute a basis for further investigation of metabolism in the structures of the spine.

Metabolic and haemodynamic changes in the pathologic hypermobile spine

The purpose of the study was to evaluate whether pathologic hypermobility of the lumbar spine could produce haemodynamic, metabolic, and histologic changes similar to those found in osteoarthritis. Five adult goats were surgically made hypermobile in the lumbar spine by an extensive laminectomy involving exarticulation of the facet joints of the L4 and L5 levels. Seven months following the operation oxygen partial pressure (pO 2), was measured in situ in the nucleus pulposus and in the adjacent lumbar body of the hypermobile segment. A segment three levels more cranially served for control. Mass spectrometry was used for continuous registration of pO 2. Intraosseous pressure (IOP) was measured in the lumbar bodies of the same levels. Hypermobility averaged a 60 per cent increase at the operated segment as measured on flexion-extension radiograms preoperatively and 7 months postoperatively. The hypermobile discs had decreased in height as measured by CT scanning and this was confirmed by histologic sections. Significant hypoxia was found in the nucleus pulposus of the hypermobile segment, while increased pO 2 and IOP existed in the adjacent lumbar body.

Fetal lumbar spine: measuring axial growth with US.

Ultrasound (US) can be used to visualize vertebral segments, suggesting a quantitative means of studying vertebral column growth in utero and thus a means of detecting developmental abnormalities. US images of the lumbar spine were obtained in 128 clinically normal fetuses between the gestational age of 11 through 41 weeks. A large-aperture, dynamically focused US system capable of regional magnification was used. Average lumbar spacing was calculated from distance between centrums of at least four lumbar bodies. The average distance between lumbar centrums increased nearly linearly throughout the second and third trimesters (r2 = 0.98). Enhanced anatomic display implies new capabilities for recognizing developmental abnormalities antenatally.

Post-poliomyelitis paralytic scoliosis. A review of curve patterns and results of surgical treatments in 118 consecutive patients.

Curve patterns and surgical treatment in 118 consecutive patients with post-poliomyelitic paralytic scoliosis are reviewed. The typical curve pattern was double structural curves, usually including the lumbar spine. Modifying the incision and altering the sequence of instrumentation facilitated both the exposure and instrumentation of the fourth and fifth lumbar bodies. Anterior fusion and Dwyer's instrumentation yield most of the correction of pelvic obliquity and significant correction of both the upper and lower curves. Two weeks of halofemoral traction did not achieve significant curve correction. It is suggested that staged anterior and posterior procedures result in structural correction of pelvic obliquity and paralytic scoliosis in severe deformities equal to the degree of correction obtained using posterior fusion and instrumentation alone in less severe cases.

Some aspects of aging in the lumbar spine.

I measured the bodies of vertebrae L3 and L4 of 338 skeletons from the Terry collection in the Smithsonian Institution, including Blacks and Whites, males and females, aged from 20 to 90 years. Transverse breadths of the upper and lower endplates (excluding osteophytes) and minimum transverse breadths all increase with age. In general, the greater broadening occurs in the endplates, but the middle of the body also broadens to such a degree that there is no demonstrable increase in vertebral "flaring" with age. In males, posterior body height decreases relative to anterior height, so that the lumbar bodies become more wedge-shaped with age but females show essentially no change. Anterior height decreases in proportion to minimum breadth, so that the lumbar bodies become relatively lower and broader, and this change is significantly correlated with age in all groups. Midbody height decreases relative to anterior height, so that Nordin's biconcavity index is reduced with age. The increase in biconcavity remains evident even when average anterior-posterior height is used to calculate the index. At all age levels a high percentage of individuals have biconcavity indices of 80% or less, indicating that Nordin's standard of normality for this index, established from measurement on radiographs of the living, should be revised downward for use in evaluating osteoporosis in skeletal populations.

Seat Belt Fractures

Seat belt fractures may be expected more frequently in the future since seat belt installation is now mandatory and public awareness as to the protective value of seat belts is growing. High-speed collisions with the seat belt loose or placed cephalad to the iliac crest bring about this injury (3). The fracture is produced by acute forward flexion of the spine across the resisting belt. With the ligamentous structures remaining intact a horizontal splitting of the vertebrae results. The rent begins in the spinous process or lamina, extending through the pedicles and into the posterior aspect of the vertebral body. The transverse process may be fractured horizontally as well. Compression of the anterior aspect of the body may also be encountered. The constant deformity, however, is the peculiar transverse fracture with posterior separation without dislocation or subluxation. Neurological defects were not encountered in any of the five previously reported cases (1, 2, 3). However, in one of our cases transient numbness and tingling of both lower extremities were followed by persistent weakness in dorsiflexion of the feet. One or more of the upper three lumbar bodies have thus far been the site of involvement. In each of our cases a large hematoma was present over the fracture site which further drew attention to the injury. Seat belt fractures of a lesser extent, for instance those involving only the lamina, pedicle, or spinous process, may be overlooked as we are accustomed to viewing the vastly more common vertebral body compression and vertical fractures of the transverse processes. Treatment consists of immobilization in extension, which reduces the angulation. In one of our cases an H-graft fusion was also employed. Case I: This 21-year-old male was involved in a high-speed collision with a large tree. He was in the back seat of a sedan with the seat belt in use. Looseness of the belt was denied. The abdominal bruises produced by the seat belt were cephalad to the iliac crest. A hematoma was present posterior to the L-2 body. The vertebra was fractured just above the spinous process with the fracture traversing the pedicle and entering the posterior and inferior aspects of the vertebral body with the transverse process also fractured horizontally. A horizontal rent was also present in the spinous process of the L-1 body. The lamina was not entered. No neurological defects were present. Fixation and extension were delayed for one week. This delay resulted in a mild gibbous deformity at the L-2 level. Case II: The 20-year-old brother of the above patient was involved in the same accident and seated on the same seat. Here again, looseness of the seat belt was denied. The bruises were above the level of the iliac crest. A similar, obvious hematoma was present over the fracture site. The spinous process, pedicles, and transverse processes of L-1 were fractured horizontally.

Congenital fusion of three lumbar vertebral bodies.

Congenital fusion of cervical vertebral bodies is fairly common, thoracic fusion occurs less frequently, while fusion of lumbar vertebral bodies is rare. The authors had previously seen cases in which two lumbar vertebral bodies were fused, but the case to be reported here is the first which they have encountered of congenital fusion of three lumbar vertebrae. Literature Evans (1), in an excellent paper, has adequately reviewed the embryology of the vertebral column. According to him, fusion occurs most frequently at the cervical level, and occasionally at the thoracic. At the time of presentation of his paper, he had not seen fusion of any of the lumbar vertebrae. Trial and Rescanieres (5) reported 3 cases of lumbar vertebral body fusion. In 1 the second and third lumbar bodies were fused; in another the twelfth thoracic and first lumbar bodies, and in the third the fourth and fifth lumbar bodies. The arches were normal. These authors believe that fusion is due to congenital absence of the vertebral disk...

Spondylolisthesis without isthmus defect.

With the development and widespread use of the moving grid in the 1920's, permitting satisfactory roentgenographic study of the lower spine, good understanding of congenital and acquired bone lesions in this area has become almost universal among roentgenologists, orthopedists, and industrial physicians interested in the low back. A great body of literature has developed concerning anomalies, residues of trauma, and degenerative disease of intervertebral disks and bone. We have observed in increasing frequency in older age groups, but in many who have presented low back problems in industry, a lesion which we believe has not had sufficient recognition. This belief is based on the sparse attention given to the lesion in the standard textbooks and in the literature (1, 2) and on discussion with our colleagues interested in diagnostic roentgenology and orthopedics. Spondylolisthesis, the term used to describe the extensive cases first observed by Kilian (3), may be translated literally as “falling of the vertebrae.” He dealt with extreme cases of forward dislocation of the fifth lumbar vertebral body over the sacrum, resulting in a large palpable mass in the pelvis, partially blocking the pelvic inlet in obstetrical cases. Most of the common cases now seen in x-ray study show only limited displacement, and spondylolisthesis has come to mean forward (or backward) slipping of one or more vertebral bodies on the segment below. Spondylolisthesis resulting from a defect in the isthmus or pars interarticularis has been recognized as a frequent and important structural lesion of the low spine. Spondylolisthesis also results, though less frequently, from anomalies of the articular processes and facets, fractures of the isthmus or articular processes, and destruction of these parts by inflammatory or malignant disease. In our experience, however, an increasing number of individuals have been seen with varying degrees of spondylolisthesis due to erosion of the facet joints in the lower spine by a degenerative arthritic process. The erosion of the cartilage and the subchondral bone in response to mechanical stress over the years is sufficient in some cases to permit forward displacement of certain lumbar bodies more than 1 cm. (Figs. 1 and 2). This process was apparently first described by Junghanns (2) in 1931 as “pseudospondylolisthesis.” We prefer to describe the lesion as a form of spondylolisthesis, recognizing that forward (or backward) slipping can result from a variety of causes. There are a few simple points of differentiation between spondylolisthesis resulting from isthmus defect and that due to degenerative arthritic erosion of the facet joints as demonstrated on lateral roentgenograms. When the lesions are clear cut and sharply defined, the interpretation is not difficult.

Anatomical and Postural Variations of the Lumbosacral Spine

IT scarcely seems possible to condense the various features of this subject briefly. My theme, however, may be stated as follows: 1. The lumbosacral area is a transitional area of the spine, i.e., the fifth lumbar vertebra may partake of characteristics of a sacral segment, and, conversely, the first sacral segment may seem to rise and assume characteristics of the lumbar vertebra, in about 10 per cent of all individuals. 2. Failure of the neural arches of the fifth lumbar and first sacral segment to completely close are found in at least 20 per cent of individuals. This produces a spina bifida occulta, with X-ray shadows frequently misinterpreted as fracture. 3. A straight spine seems to be the exception. An individual lists to one side or presents an evident scoliosis. This condition is not abnormal, is purely postural, is not pathological and is not the result of trauma. X-ray shadows of a lumbar curve, with rotation of lumbar bodies, are presented upon the plates and these should not be misinterpreted...