Assessment of sagittal spinopelvic parameters in a Taiwanese population with spondylolysis by the EOS imaging system: a retrospective radiological analysis.

BACKGROUND: The impact of sagittal spinopelvic alignment on spondylolysis is well established in Caucasian populations. However, prior studies suggest that people from different ethnological backgrounds showed divergence, and a few studies that focused on Asian populations reported conflicting results. The aim of this study is to use the EOS imaging system to evaluate the spinopelvic parameters of spondylolysis patients, and their relationship with spondylolisthesis, disc degeneration, and age in a Taiwanese population. METHODS: Radiographic sagittal spinopelvic parameters for 45 spondylolysis patients and 32 healthy people were evaluated, including pelvic incidence (PI), sacral slope (SS), pelvic tilt (PT), thoracic kyphosis (TK), and lumbar lordosis (LL). The spinopelvic parameters were compared between spondylolytic and control groups. These parameters were further compared between spondylolytic subjects with and without spondylolisthesis, with and without high-grade disc degeneration, and young (< 30 years old) and middle-aged. RESULTS: The PI and LL of the spondylolytic group (52.6°±12.0° and 41.3°±15.2°) were significantly higher than those of the healthy control group (47.16°±7.95° and 28.22°±10.65°). Further analysis of the spondylolytic patients revealed that those with high-grade disc degeneration were more prone to spondylolisthesis (92.3 %) compared to those without (50 %; p = 0.001). The middle-aged group had significantly higher rates of spondylolisthesis (80 %) and high-grade disc degeneration (52.4 %) compared with those for the young group (45 and 16.7 %, respectively; p = 0.017 and 0.047, respectively). No statistically significant difference in the sagittal spinopelvic parameters was found when spondylolytic patients were divided according to the occurrence of spondylolisthesis or high-grade disc degeneration. CONCLUSIONS: In a Taiwanese population, PI and LL were significantly larger in spondylolytic patients. Disc degeneration and age were associated with the occurrence of spondylolisthesis. Ethnological differences should thus be taken into account when making clinical decisions regarding spondylolysis in a Taiwanese population.

Clinical applications of nuclear medicine in the diagnosis and assessment of musculoskeletal sports injuries. / Aplicaciones clínicas de la medicina nuclear en el diagnóstico y evaluación de las lesiones deportivas musculoesqueléticas.

Increased participation in sports and physical exercise are widely promoted as an approach to a physically active lifestyle which has a positive effect on healthy aging, in patients and athletes of all ages, beginners and experts, including amateur athletes and professional athletes. Unfortunately, this has caused a higher incidence of sports-related injuries. In the sports context, the early and accurate diagnosis of injuries is of the utmost importance in order to enable early treatment to achieve a full recovery. Imaging techniques are increasingly important for the successful diagnosis and management of the patient. The nuclear medicine techniques with bone tracers provide physiological and metabolic information in the early phases of musculoskeletal injuries, which often precede anatomical changes and they reflect changes in bone turnover. This allows early diagnosis, along with evaluation of the activity and phase of the injury. In this article, the applications of nuclear medicine techniques, focusing on bone scintigraphy, alongside the important contribution of hybrid studies (SPECT/CT), in the diagnosis of bone and soft tissue sports injuries, will be described. In addition, we explain their usefulness in the expression of the pathophysiology of these lesions and their scintigraphic patterns. The article will also describe biomechanical and physiopathological aspects, injury mechanisms and clinical presentations of bone and joint sports injuries, knowledge of this is essential for the correct diagnostic assessment of imaging studies.

Prevalence of Spondylolysis in Symptomatic Adolescent Athletes: An Assessment of Sport Risk in Nonelite Athletes.

OBJECTIVE: To assess the risk of spondylolysis by sport in nonelite adolescent athletes with low back pain (LBP). DESIGN: Retrospective case series. SETTING: Hospital-based sports medicine clinic. PATIENTS: The medical charts of 1025 adolescent athletes with LBP (age 15 ± 1.8 years) were examined; 308 (30%) were diagnosed with a spondylolysis. ASSESSMENT OF RISK: Risk of spondylolysis was assessed in 11 sports for males and 14 sports for females. MAIN OUTCOME MEASURE: Relative risk of diagnosis of spondylolysis injury. RESULTS: The risk of spondylolysis differed by sex with baseball (54%), soccer (48%), and hockey (44%) having the highest prevalence in males and gymnastics (34%), marching band (31%), and softball (30%) for female athletes. Baseball was the only sport to demonstrate a significant increased risk of spondylolysis. CONCLUSIONS: The sports with the greatest risk of spondylolysis in adolescent athletes in this study were not consistent with published literature. Clinicians should be cautious generalizing high-risk sports to their practice, as geographic region and level of the athlete may significantly influence the incidence of spondylolysis in the population they are treating.

Imaging Pediatric Spondylolysis: A Systematic Review.

STUDY DESIGN: A systematic review. OBJECTIVE: The aim of this study was to provide an evidence-based recommendation for when and how to employ imaging studies when diagnosing back pain thought to be caused by spondylolysis in pediatric patients. SUMMARY OF BACKGROUND DATA: Spondylolysis is a common structural cause of back pain in pediatric patients. The radiologic methods and algorithms used to diagnose spondylolysis are inconsistent among practitioners. METHODS: A literature review was performed in PubMed and Cochrane databases using the search terms "spondylolysis," "pediatric," "adolescent," "juvenile," "young," "lumbar," "MRI," "bone scan," "CT," and "SPECT." After inclusion criteria were applied, 13 articles pertaining to diagnostic imaging of pediatric spondylolysis were analyzed. RESULTS: Ten papers included sensitivity calculations for comparing imaging performance. The average sensitivity of magnetic resonance imaging (MRI) with computed tomography (CT) as the standard of reference was 81.4%. When compared with single-photon emission CT (SPECT), the average sensitivity of CT was 85% and the sensitivity of MRI was 80%. Thirteen studies made a recommendation as to how best to perform diagnostic imaging of patients with clinically suspected spondylolysis. When compared with two-view plain films, bone scans had seven to nine times the effective radiation dose, while four-view plain films and CT were approximately double. Of the diagnostic methods examined, MRI was the most expensive followed by CT, bone scan, four-view plain films, and two-view plain films. CONCLUSION: Due to their efficacy, low cost, and low radiation exposure, we find two-view plain films to be the best initial study. With unusual presentations or refractory courses, practitioners should pursue advanced imaging. MRI should be used in early diagnosis and CT in more persistent courses. However, the lack of rigorous studies makes it difficult to formulate concrete recommendations. LEVEL OF EVIDENCE: 3.

Confidence in Assessment of Lumbar Spondylolysis Using Three-Dimensional Volumetric T2-Weighted MRI Compared With Limited Field of View, Decreased-Dose CT.

BACKGROUND: Limited z-axis-coverage computed tomography (CT) to evaluate for pediatric lumbar spondylolysis, altering the technique such that the dose to the patient is comparable or lower than radiographs, is currently used at our institution. The objective of the study was to determine whether volumetric 3-dimensional fast spin echo magnetic resonance imaging (3D MRI) can provide equal or greater diagnostic accuracy compared with limited CT in the diagnosis of pediatric lumbar spondylolysis without ionizing radiation. HYPOTHESIS: Volumetric 3D MRI can provide equal or greater diagnostic accuracy compared with low-dose CT for pediatric lumbar spondylolysis without ionizing radiation. STUDY DESIGN: Clinical review. LEVEL OF EVIDENCE: Level 2. METHODS: Three pediatric neuroradiologists evaluated 2-dimensional (2D) MRI, 2D + 3D MRI, and limited CT examinations in 42 pediatric patients who obtained imaging for low back pain and suspected spondylolysis. As there is no gold standard for the diagnosis of spondylolysis besides surgery, interobserver agreement and degree of confidence were compared to determine which modality is preferable. RESULTS: Decreased-dose CT provided a greater level of agreement than 2D MRI and 2D + 3D MRI. The kappa for rater agreement with 2D MRI, 2D + 3D MRI, and CT was 0.19, 0.32, and 1.0, respectively. All raters agreed in 31%, 40%, and 100% of cases with 2D MRI, 2D + 3D MRI, and CT. Lack of confidence was significantly lower with CT (0%) than with 2D MRI (30%) and 2D + 3D MRI (25%). CONCLUSION: For diagnosing spondylolysis, radiologist agreement and confidence trended toward improvement with the addition of a volumetric 3D MRI sequence to standard 2D MRI sequences compared with 2D MRI alone; however, agreement and confidence remain significantly greater using decreased-dose CT when compared with either MRI acquisition. CLINICAL RELEVANCE: Decreased-dose CT of the lumbar spine remains the optimal examination to confirm a high suspicion of spondylolysis, with dose essentially equivalent to radiographs. If clinical symptoms are not classic for spondylolysis, 2D MRI is still very good at detecting spondylolysis while remaining sensitive for detection of alternative diagnoses such as disc abnormalities and pars stress reaction. The data suggest that standard 2D MRI sequences should not be entirely replaced by a volumetric T2-weighted 3D sequence (despite promising features of rapid acquisition time, increased spatial resolution, and reconstruction capability).

CT outperforms radiographs at a comparable radiation dose in the assessment for spondylolysis.

BACKGROUND: Lumbar spondylolysis, a unilateral or bilateral fracture at pars interarticularis, is a common cause of low back pain in children. The initial imaging study in the diagnosis of lumbar spondylolysis has historically been lumbar spine radiographs; however, radiographs can be equivocal or false-negative. Definitive diagnosis can be achieved with computed tomography (CT), but its use has been limited due to the dose of ionizing radiation to the patient. OBJECTIVE: By limiting the z-axis coverage to the relevant anatomy and optimizing the CT protocol, we are able to provide a definitive diagnosis of fractures of the pars interarticularis at comparable or lower radiation dose than commonly performed lumbar spine radiographs. As there is no gold standard for the diagnosis of spondylolysis besides surgery, we compared interobserver agreement and degree of confidence to determine which modality is preferable. MATERIALS AND METHODS: Sixty-two patients with low back pain ages 5-18 years were assessed for the presence of spondylolyis. Forty-seven patients were evaluated by radiography and 15 patients were evaluated by limited field-of-view CT. Both radiographic and CT examinations were assessed anonymously in random order for the presence or absence of spondylolyisis by six raters. Agreement was assessed among raters using a Fleiss Kappa statistic for multiple raters. RESULTS: CT provided a significantly higher level of agreement among raters than radiographs (P < 0.001). The overall Kappa for rater agreement with radiographs was 0.24, 0.34 and 0.40 for 2, 3 or 4 views, respectively, and 0.88 with CT. CONCLUSION: Interobserver agreement is significantly greater using limited z-axis coverage CT when compared with radiographs. Radiologist confidence improved significantly with CT compared to radiographs regardless of the number of views.

Do oblique views add value in the diagnosis of spondylolysis in adolescents?

BACKGROUND: Anteroposterior, lateral, and right and left oblique lumbar spine radiographs are often a standard part of the evaluation of children who are clinically suspected of having spondylolysis. Recent concerns regarding radiation exposure and costs have brought the value of oblique radiographs into question. The purpose of the present study was to determine the diagnostic value of oblique views in the diagnosis of spondylolysis. METHODS: Radiographs of fifty adolescents with L5 spondylolysis without spondylolisthesis and fifty controls were retrospectively reviewed. All controls were confirmed not to have spondylolysis on the basis of computed tomographic scanning, magnetic resonance imaging, or bone scanning. Anteroposterior, lateral, and right and left oblique radiographs of the lumbar spine were arranged into two sets of slides: one showing four views (anteroposterior, lateral, right oblique, and left oblique) and one showing two views (anteroposterior and lateral only). The slides were randomly presented to four pediatric spine surgeons for diagnosis, with four-view slides being presented first, followed by two-view slides. The slides for twenty random patients were later reanalyzed in order to calculate of intra-rater agreement. A power analysis demonstrated that this study was adequately powered. Inter-rater and intra-rater agreement were assessed on the basis of the percentage of overall agreement and intraclass correlation coefficients (ICCs). PCXMC software was used to generate effective radiation doses. Study charges were determined from radiology billing data. RESULTS: There was no significant difference in sensitivity and specificity between four-view and two-view radiographs in the diagnosis of spondylolysis. The sensitivity was 0.59 for two-view studies and 0.53 for four-view studies (p = 0.33). The specificity was 0.96 for two-view studies and 0.94 for four-view studies (p = 0.60). Inter-rater agreement, intra-rater agreement, and agreement with gold-standard ICC values were in the moderate range and also demonstrated no significant differences. Percent overall agreement was 78% for four-view studies and 82% for two-view studies. The radiation effective dose was 1.26 mSv for four-view studies and 0.72 mSv for two-view studies (difference, 0.54 mSv). The charge for four-view studies was $145 more than that for two-view studies. CONCLUSIONS: There is no difference in sensitivity and specificity between four-view and two-view studies. Although oblique views have long been considered standard practice by some, our data could not identify a diagnostic benefit that might outweigh the additional cost and radiation exposure.

Radiographic assessment of lumbar facet distance spacing and pediatric spondylolysis.

STUDY DESIGN: Retrospective radiographic review. OBJECTIVE: The purpose of this article was to explore the relationship between interfacet spacing and pediatric spondylolysis. SUMMARY OF BACKGROUND DATA: Recent literature suggests that a potential cause of spondylolytic defects in adults is a narrowed interfacet spacing in the lower lumbar spine. This lack of space places them at increased risk for pars fractures with repetitive lumbar hyperextension. This relationship has not been explored in a pediatric population. METHODS: The anteroposterior lumbar spine radiographs of 41 pediatric patients with spondylolytic defects were compared with 41 unaffected controls. A standard digital caliper was used to measure interfacet distance. Vertebral body width and interpedicular distance were recorded as internal standards to control for varying vertebral size. Statistical analysis exploring the relationships of interfacet distances between the affected and unaffected groups was performed using a Mann-Whitney U test. RESULTS: The absolute increase in interfacet distance between adjacent levels was significantly smaller at the L4/L5 level in spondylolytic individuals (P = 0.023). When interpedicular distance was used to standardize for vertebral body size, a significantly smaller increase in the interpedicular distance was noted at the L4/5 level in spondylolytic individuals (P = 0.026). Similar results were obtained when body width was used to standardize for vertebral body size (P < 0.001). A similar trend was noticed at the L3/4 level when standardizing with interpedicular distance although these results were not significant (P = 0.098). CONCLUSION: A likely explanation for the etiology of lumbar pars defects is insufficient caudal increase in lumbar interfacet spacing. Further prospective studies are necessary to determine if unaffected individuals with a narrowed interfacet spacing are at increased risk of developing spondylolytic defects later in life.

Radiographic assessment of lumbar facet distance spacing and spondylolysis.

STUDY DESIGN: Spondylolytic defects at L5 are influenced by insufficient differential spacing between the inferior articular facets of L4 and superior facets of S1. These structures then impinge on the intervening L5 pars interarticularis during hyperlordosis, contributing to fracture and resorption of the pars. OBJECTIVES: Articular facet spacing was evaluated on clinical radiographs of normal and spondylolytic patients. SUMMARY OF BACKGROUND DATA: Spondylolysis ranges from a hairline fracture through the pars to a complete pseudarthrotic defect. Insufficient increase in the distance between articular facets from L4-L5 to L5-S1 has been associated with chronic lytic defects in a skeletal sample. METHODS: Anteroposterior radiographs of 39 patients with L5-S1 spondylolysis were compared with radiographs from 42 normal individuals. Differences in transverse distances between lumbar articular facets and pedicles were compared using 2-tailed t tests. RESULTS: Patients with spondylolysis exhibited a smaller increase in interfacet distance from the L3-L4 facet joints to the L5-S1 joints than do normal patients, even relative to vertebral size. CONCLUSIONS: Spondylolytic fractures at L5 are influenced by an inadequate increase in interfacet distances between adjacent vertebrae. Individuals lacking sufficient increase in lower lumbar transverse interfacet dimensions are at greater risk of developing and maintaining spondylolytic defects.

Assessment of bony union following surgical stabilisation for lumbar spondylolysis: a comparative study between radiography and computed tomography.

PURPOSE: To compare the status of bony union seen on plain radiography versus computed tomography (CT) following tension band repair for refractory spondylolysis. METHODS: 14 patients (12 men and 2 women; mean age, 23 years; age range, 16-56 years) with a mean follow-up period of 6.35 years were included. All patients were operated on by one senior surgeon using either a Scott procedure (n=2) or van Dam modification of the Scott procedure (n=12). Bony union of the pars was assessed using both plain radiography (anteroposterior, lateral, and oblique views) and reverse gantry CT. The presence of bony union was determined if a bridging bone was shown in the images. The Oswestry Disability Index was measured at 6-year follow-up. RESULTS: 13 (93%) of 14 patients showed bony union on plain/oblique radiographs versus 7 (50%) on CT scan. The mean Oswestry Disability Index was 28 (good to excellent). The high incidence of nonunion shown on CT scanning did not correlate well with clinical results. CONCLUSION: Bony nonunion is more difficult to visualise on plain radiographs than reverse gantry CT. CT demonstrates more clearly the presence or absence of the bridging bone. Clinical results do not correlate with bony union, indicating that bony union is not required to achieve good results.

Lumbar spinal stenosis assessment with computed tomography, magnetic resonance imaging, and myelography.

Degenerative spinal stenosis of the lumbar spine is caused by many factors, some of which include: disc herniation, ligamentum flavum and facet hypertrophy, spondylolisthesis, and compression fracture. Most often the stenosis is caused by a combination of these factors. The imaging modalities in routine use to evaluate these conditions are computed tomography, magnetic resonance imaging and computed tomography-myelogram. They each have their advantages and disadvantages although any one of these modalities can adequately diagnose lumbar stenosis. The overall accuracy rate of computed tomography, magnetic resonance imaging, and computed tomography-myelogram has been reported to be similar and even complimentary. It is recommended that the least invasive modality be performed first. Magnetic resonance imaging should be the first choice because it does not require ionizing radiation or contrast injection. The aim of the current study is to present the common causes of lumbar stenosis. Where appropriate, each case is shown with images from each modality so that their similarities and differences can be highlighted.

Lumbar spine: quantitative and qualitative assessment of positional (upright flexion and extension) MR imaging and myelography.

PURPOSE: To compare measurements of the sagittal diameter of the lumbar dural sac obtained at positional magnetic resonance (MR) imaging and at functional myelography and to assess the influence of various body positions on the dural sac and the intervertebral foramina. MATERIALS AND METHODS: Thirty consecutive patients referred for lumbar myelography were examined with an open 0.5-T MR imager, Sagittal T2-weighted fast spin-echo images were acquired with patients in the supine, upright flexion, and upright extension positions. The midsagittal diameter of the dural sac was measured at the level of the disks on MR images and myelograms. Foraminal sizes on the MR images were scored independently by two observers. RESULTS: Correlation between MR imaging and myelographic measurements was high (r = .81-.97). A small but statistically significant positional dependence of the dural sac diameter was found in the lower lumbar spine. Position-dependent differences in foraminal scores were uncommon. CONCLUSION: Quantitative assessment of sagittal dural sac diameters is comparable between lumbar myelography and positional MR imaging. In a selected patient population, only small changes in the sagittal diameter of the dural sac and foraminal size can be expected between various body positions, and the information gained in addition to that from standard MR imaging is limited [corrected].

Bone scintigraphy in the assessment of spondylolysis in patients attending a sports injury clinic.

Thirty-three patients attending the Nottingham Sports Injury Clinic in whom a clinical diagnosis of a stress fracture of the pars interarticularis was made were evaluated with both radiography and bone scintigraphy. This was done in an effort to distinguish a recent stress fracture which would produce a positive scintigram from an established 'incidental' spondylolysis giving a normal scintigram. Nine patients demonstrated abnormal radiography with a normal scintigram. A further nine patients had a positive scintigram. Six were associated with a spondylolysis indicating a recent stress fracture but two had normal radiography suggesting a stress fracture in the 'sub-radiological' phase. One patient had increased uptake in relation to degenerative changes of the lower lumbar facet joints. Oblique views of the scintigram helped in localisation of the abnormal uptake to the pars interarticularis.

Radiographic assessment of anatomic deviations in lumbar spondylolysis.

A series of 202 patients (133 men, 69 women) with spondylolysis were examined with respect to radiographic variables describing lumbosacral lordosis, size of lumbar vertebrae, transverse processes and disc height. An age-standardized and sex-stratified comparison was made with a control group of 170 subjects (68 men, and 102 women) without lumbar spine disorders. The difference in lumbosacral lordosis between the spondylolysis and control groups was considered to be secondary to olisthesis, and to lack an etiologic role for the genesis of lysis. The lengths of the transverse processes and their distances to the crista iliaca posterior demonstrated no differences between the groups and therefore did not seem relevant to the context of the pathogenesis of spondylolysis. The fifth lumbar vertebra in the spondylolytic patients was more wedged and less wide than in the controls. The question of the primary or secondary nature of this change has not yet been clearly elucidated, and should be given further attention. The spondylolytic patients demonstrated a decrease in the height of the L5-S1 disc much earlier than the controls, and the degree of narrowing of the disc space was much more marked.