Comparison of cone beam computed tomography and plane radiographs of radial fractures as a basis for radiographical measurements.

BACKGROUND: The purpose of this study was to determine whether radiological measurements of radial fracture position made in cone beam computed tomography (CBCT) projection images are comparable to those made on traditional radiographs and could potentially substitute them. METHODS: Sixteen patients with fractures of the distal radius referred for radiographs were recruited for an additional CBCT scan which was performed immediately afterwards. Projection images and volumetric data were saved from the CBCT scans. Measurements of ulnar variance, radial inclination and volar tilt were made from all three sets of images. RESULTS: Agreement of projection image based measurements with radiographs was nearly as good as as the agreement of cross sectional image measurements with radiographs. The average difference between the results for projection images and radiographs were -1.2 mm (SD 1.9 mm), for radial inclination 0.7° (SD 2.9°) and for volar tilt 1.9° (SD 5.6°). CONCLUSION: Differences between radiological measurements between the modalities studied are small and projection images could be used for the assessment of distal radial fractures.

Reliability of T2-weighted signal intensity-based quantitative measurements and visual grading of lumbar disc degeneration on MRI.

BACKGROUND: Decrease in signal intensity (SI) of the nucleus pulposus (NP) on T2-weighted (T2W) images, a sign of disc degeneration (DD), is usually graded based on an observer's image interpretation. No gold standard for quantitative assessment of NP SI exists to date. PURPOSE: To compare different quantitative methods and visual gradings of lumbar DD and to evaluate the ability of the quantitative methods to differentiate DD grades. MATERIAL AND METHODS: The mean SI of 95 lumbar discs was measured from sagittal T2W images using three regions of interest (ROI): the whole disc, ellipsoid ROI on the NP, and targeted ROI on the most homogenous, brightest area of the NP. SI values were adjusted with cerebrospinal fluid (CSF) SI and compared with vertebral bone SI-adjusted values. DD was evaluated with Pfirrmann grading and visual grading of NP SI. Intra- and inter-observer agreements and relationships between measurements and visual gradings were assessed. RESULTS: Repeatability of all measurements was excellent. All measurements had a strong correlation with Pfirrmann grading and visual NP SI grading, and the CSF SI-adjusted values had a stronger correlation than the vertebral bone SI-adjusted values. The SI values obtained with the targeted ROI had the most significant differences between visual DD grades. CONCLUSION: Quantitative measurement of the NP SI provides a reliable method for evaluating lumbar DD. Targeted selection of the NP structures included in the measurement offers the best differentiation of DD grades. A reliable quantitative method for DD evaluation is needed for the development of machine-learning-based DD classification.

Post-traumatic spinal hematoma in ankylosing spondylitis.

PURPOSE: The purpose of this study is to examine the incidence, location, and magnetic resonance imaging (MRI) features of spinal epidural hematoma (SEH) and spinal subdural hematoma (SSH) in post-traumatic ankylosing spondylitis (AS) patients. METHODS: A total of 2256 consecutive referrals for urgent and emergency MRI scans of the spine over a period of eight years and nine months were manually reviewed for any mentions indicating axial ankylosis and post-traumatic spinal hematoma. We found 164 patients with ankylosed spines complicated by spinal fracture, of whom 32 had AS. Of the 132 excluded patients, 80 had diffuse idiopathic skeletal hyperostosis (DISH). The primary outcome was the presence of spinal hematoma, and the secondary outcome was spinal canal narrowing and spinal cord impingement. Two musculoskeletal radiologists and one fellow in musculoskeletal radiology reviewed the images for the presence of spinal hematoma and related signal characteristics, blinded to one another and initial reports. RESULTS: Of 28 post-traumatic AS patients, 19 had SEHs and five had spinal SSHs. There was a statistically significant difference between Frankel grades before and after surgery in respect of neurological improvement (p = 0.008). Patients who had radiologically proven spinal cord impingement showed more severe neurological deficits (p = 0.012). Hematomas with T1 heterogeneity showed a significantly increased delay (p = 0.047) between injury and imaging, while other signal characteristics were only approximate. CONCLUSIONS: Both SEH and SSH are common complications in post-traumatic AS patients. Patients benefit from surgery, but the relevance of spinal hematoma as a separate factor causing neurological deficit remains unclear.

Present Status of Musculoskeletal Radiology in Europe: International Survey by the European Society of Musculoskeletal Radiology.

No official data exist on the status of musculoskeletal (MSK) radiology in Europe. The Committee for National Societies conducted an international survey to understand the status of training, subspecialization, and local practice among the European Society of Musculoskeletal Radiology (ESSR) partner societies. This article reports the results of that survey. An online questionnaire was distributed to all 26 European national associations that act as official partner societies of the ESSR. The 24 questions were subdivided into six sections: society structure, relationship with the national radiological society, subspecialization, present radiology practice, MSK interventional procedures, and MSK ultrasound. The findings of our study show a lack of standardized training and/or accreditation methods in the field of MSK radiology at a national level. The European diploma in musculoskeletal radiology is directed to partly overcome this problem; however, this certification is still underrecognized. Using certification methods, a more homogeneous European landscape could be created in the future with a view to subspecialist training. MSK ultrasound and MSK interventional procedures should be performed by a health professional with a solid knowledge of the relevant imaging modalities and sufficient training in MSK radiology. Recognition of MSK radiology as an official subspecialty would make the field more attractive for younger colleagues as well as attracting the brightest and best, an important key to further development of both clinical and academic radiology. KEY POINTS: · Standardized training and/or accreditation methods in the field of MSK radiology is lacking at a national level.. · With certification methods, such as the European diploma in musculoskeletal radiology, a more homogeneous European landscape could be created in the future with a view to subspecialist training.. · Recognition of MSK radiology as an official subspecialty would make the field more attractive for younger colleagues as well as attracting the brightest and best, an important key to further development of both clinical and academic radiology..

Disc Degeneration of Young Low Back Pain Patients: A Prospective 30-year Follow-up MRI Study.

STUDY DESIGN: A prospective follow-up study. OBJECTIVE: The aim of this study was to investigate whether early lumbar disc degeneration (DD) in young low back pain (LBP) patients predicts progression of degenerative changes, pain, or disability in a 30-year follow-up. SUMMARY OF BACKGROUND DATA: MRI is an accurate method for studying degenerative changes in intervertebral discs. Decreased signal intensity (SI) can be used as indication of decreased water content. Long-term prognosis of early DD remains unclear. METHODS: In an earlier study, 75 conscripts aged 20 years with LBP had their lumbar spine examined by MRI. At a follow-up of 30 years, the subjects were contacted; 35 of 69 filled a pain and disability questionnaire, and 26 of 35 were also reexamined clinically and by MRI. The images were evaluated for decreased SI and other degenerative changes. Association between decreased SI of a disc at baseline and the presence of more severe degenerative changes in the same disc space at follow-up was analyzed using Fisher exact test. Association between decreased baseline SI and pain/disability scores from the questionnaire was analyzed with Kruskal-Wallis H test. RESULTS: The total number of lumbar discs with decreased SI increased from 23 of 130 (18%) to 92 of 130 (71%)-from 0.9 to 3.5 per subject during the follow-up. Distribution of DD changed from being mostly in L4-L5 and L5-S1 discs to being almost even between the four lowermost discs. Discs that had even slightly decreased SI at baseline were more likely to have severely decreased SI at follow-up, compared to healthy discs (57% vs. 11%, P < 0.001). Other degenerative changes were also more common in these discs. Severity of DD at baseline did not have a significant association with current pain or disability. CONCLUSION: In young LBP patients, early degeneration in lumbar discs predicts progressive degenerative changes in the respective discs, but not pain, disability, or clinical symptoms. LEVEL OF EVIDENCE: 4.

Letrozole Monotherapy in Pre- and Early-Pubertal Boys Does Not Increase Adult Height.

Background: Aromatase inhibitors (AIs) have been used in boys with idiopathic short stature (ISS) to promote growth despite the lack of actual data regarding treatment effect on adult height. In this study, we characterized adult heights and long-term follow-up in AI-treated boys with ISS. Methods: Adult heights and long-term follow-up data, including spine MRIs, of a randomized, double-blind, placebo-controlled trial of boys who were treated with letrozole (Lz) (2.5 mg/d) or placebo (Pl) for 2 years during prepuberty and early puberty. The mean bone ages at treatment cessation were 10.2 and 10.8 years, respectively. Results: Adult heights were similar between the boys treated with Lz (n = 10) and those who received Pl (n = 10) (164.8 ± 4.0 vs. 163.7 ± 3.7 cm, p = 0.49, respectively). In either group, the adult heights did not differ from predicted adult heights at start of the study [Pl: 163.7 (3.7) cm vs. 166.9 (3.3), p = 0.06; Lz: 164.8 (4.0) cm vs. 167.6 (7.9), p = 0.20, respectively]. Long-term follow-up data showed that the frequency of subjects with a vertebral deformity was similar between the groups (Lz, 29% and Pl, 22%, p = 0.20), and no single comorbidity was clearly enriched in either group. Conclusions: The Lz-treated boys had similar adult heights with the subjects who received Pl for 2 years, which indicates that the treatment is not beneficial when given to pre- or early-pubertal boys. Previously observed vertebral deformities ameliorated during follow-up, which supports the skeletal safety of Lz therapy in children and adolescents.

Cross-sectional area of the paraspinal muscles and its association with muscle strength among fighter pilots: a 5-year follow-up.

BACKGROUND: A small cross sectional area (CSA) of the paraspinal muscles may be related to low back pain among military aviators but previous studies have mainly concentrated on spinal disc degeneration. Therefore, the primary aim of the study was to investigate the changes in muscle CSA and composition of the psoas and paraspinal muscles during a 5-year follow up among Finnish Air Force (FINAF) fighter pilots. METHODS: Study population consisted of 26 volunteered FINAF male fighter pilots (age: 20.6 (±0.6) at the baseline). The magnetic resonance imaging (MRI) examinations were collected at baseline and after 5 years of follow-up. CSA and composition of the paraspinal and psoas muscles were obtained at the levels of 3-4 and 4-5 lumbar spine. Maximal isometric strength tests were only performed on one occasion at baseline. RESULTS: The follow-up comparisons indicated that the mean CSA of the paraspinal muscles increased (p < 0.01) by 8% at L3-4 level and 7% at L4-5 level during the 5-year period. There was no change in muscle composition during the follow-up period. The paraspinal and psoas muscles' CSA was positively related to overall maximal isometric strength at the baseline. However, there was no association between LBP and muscle composition or CSA. CONCLUSIONS: The paraspinal muscles' CSA increased among FINAF fighter pilots during the first 5 years of service. This might be explained by physically demanding work and regular physical activity. However, no associations between muscle composition or CSA and low back pain (LBP) experienced were observed after the five-year follow-up.

Chronic low back pain in relation to Modic changes, bony endplate lesions, and disc degeneration in a prospective MRI study.

PURPOSE: To clarify the significance of Modic changes, bony endplate lesions, and disc degeneration as predictors of chronic low back pain (LBP) during 1-year follow-up. METHODS: 49 patients with severe, non-specific, chronic LBP, and Modic 1 lesion (M1) were prospectively studied with MRI and questionnaire. Changes in grade of disc degeneration, severity of Modic changes, Schmorl lesions, and bony endplate irregularities were evaluated and changes assessed in LBP intensity on numeric rating scale 0-10 and severity with Oswestry disability index 0-100 (ODI). Association between change in MRI findings and symptoms was computed using generalized estimating equations analysis. RESULTS: Although pain decreased in most patients during 1-year follow-up, it increased or persisted in 36 %. Change in M1, M2, bony endplate lesions, and signal intensity (SI) and height of the disc associated with change of pain intensity, while change in M1, bony endplate lesions, and disc height associated with change of ODI. Not only persistent M1s, increasing bony endplate lesions, decreasing disc height, and M2s, but also new M2s predicted persistence of pain, while decrease of M1s and SI of the disc and increase of size of M2s predicted decrease of pain. Changes in disc bulges did not associate with pain. CONCLUSIONS: In patients with chronic non-specific LBP, persisting M1, decreasing disc height, and increasing bony endplate lesions associated with persisting pain while decrease of SI of the disc with decrease of pain. Such changing MRI findings in the same disc space have earlier been shown to progress abnormally fast. They may be signs or biomarkers of a prolonged pain causing, deforming degenerative process, and should lead to considering early intervention or specific treatments to affect that process.

Modic type I change may predict rapid progressive, deforming disc degeneration: a prospective 1-year follow-up study.

INTRODUCTION: This prospective magnetic resonance imaging (MRI) study in chronic low-back pain (CLBP) patients evaluated the natural course of degenerative lumbar spine changes in relation to Modic 1 type changes (M1) within 1 year. MATERIALS AND METHODS: From 3,811 consecutive CLBP patients referred to lumbar spine MRI 54 patients with a large M1 were selected using strict exclusion criteria to exclude specific back disorders. Follow-up MRI was obtained within 11-18 months. RESULTS: At baseline M1 was associated with an adjacent endplate lesion in 96% of the cases. In follow-up, an unstable M1 was associated both with an increase of endplate lesions, decrease of disc height and change in disc signal intensity, most found at L4/5 or L5/S1. In disc spaces without M1, progression of degenerative changes was rare. CONCLUSION: Endplate deformation, decreasing disc height and change of disc signal intensity appear essential features of accelerated degenerative process associated with M1.

Prevalence of vertebral compression fractures and associated factors in children and adolescents with severe juvenile idiopathic arthritis.

OBJECTIVE: Vertebral fractures occur in patients with juvenile idiopathic arthritis (JIA), but data on their frequency and causes are scarce. Our cross-sectional study evaluated prevalence of compression fractures and associated factors in a high-risk pediatric population with severe JIA. METHODS: Children and adolescents with a history of treatment-resistant polyarticular-course JIA for ≥ 5 years or systemic arthritis for ≥ 3 years were recruited. Clinical examination, dietary recall, laboratory measurements, bone mineral density (BMD) measurement by dual-energy X-ray absorptiometry, and spinal radiography were performed. RESULTS: Our study included 50 patients (41 girls), of whom 6 (12%) had systemic arthritis, with a median age of 14.8 years (range 7.0-18.7 yrs) and median disease duration of 10.2 years (range 3.9-16.8 years). Ninety-four percent had used systemic glucocorticoids (GC); the median total duration of GC treatment was 7.1 years (range 0-15.5 yrs). The median weight-adjusted cumulative GC dose for the preceding 3 years was 72 mg/kg (range 0-911 mg/kg). The median bone age-corrected lumbar spine and whole-body areal BMD Z-scores were -0.8 and -1.0, respectively. Twenty-two percent had vertebral fractures, mostly thoracic. Compression fractures were associated with high disease activity, high body mass index (BMI), and high recent cumulative GC dose, but not with disease duration or BMD. Thirty percent had sustained at least 1 peripheral low energy fracture. Twenty-six percent were deemed to have significantly compromised bone health. CONCLUSION: Severe JIA is associated with a significant risk of vertebral compression fractures. Associated factors include high disease activity, high BMI, and high recent GC exposure. Further studies are needed to establish optimal prevention and treatment guidelines.

The thoracic and lumbar spine in severe juvenile idiopathic arthritis: magnetic resonance imaging analysis in 50 children.

OBJECTIVE: To determine the prevalence of vertebral fractures as a complication of juvenile idiopathic arthritis (JIA). STUDY DESIGN: This cross-sectional study evaluated the prevalence and characteristics of spinal abnormalities in 50 children (aged 7.0-18.7 years) with treatment-resistant JIA by magnetic resonance imaging. Vertebral deformities, endplate irregularities, intervertebral disc involvement, spinal canal, neural foramina, and back muscles were analyzed and correlated with clinical characteristics and bone mineral density. RESULTS: Magnetic resonance imaging revealed various abnormalities in 31 patients (62%). Vertebral compression was seen in 28%, disc degeneration in 46%, protrusions in 14%, prolapses in 4%, endplate changes in 26%, and anterior vertebral corner lesions in 16%. Two patients (4%) had mild spinal canal narrowing without medullar involvement; none had neural root compression. Six patients (12%) had mild back muscle atrophy. No correlation was observed between spinal fractures or other vertebral changes and disease activity or duration, pain or bone mineral density; patients with spinal fractures tended to have a higher recent glucocorticoid exposure (P=.086). CONCLUSION: Children with severe JIA have a high prevalence of compression fractures and other vertebral, endplate, and disc abnormalities in the thoracic and lumbar spine.

Correlation of size and type of modic types 1 and 2 lesions with clinical symptoms: a descriptive study in a subgroup of patients with chronic low back pain on the basis of a university hospital patient sample.

STUDY DESIGN: Intensity of pain and level of disability (Oswestry Disability Index [ODI]) were compared with the relative size of Modic type 1 (M1) and Modic type 2 (M2) lesions. Clinical symptoms of patients having mixed M1-M2 lesion (n = 49) were compared with patients having a "pure" M1 lesion (n = 13). OBJECTIVE: To determine the relation of the sizes of M1 and M2 lesions and the type of Modic lesion (mixed M1-M2 or pure M1 lesion) with intensity of low back pain and level of perceived disability. SUMMARY OF BACKGROUND DATA: Endplate signal abnormalities, particularly M1 changes indicating edema and inflammation, have been suggested to play an important role in the etiopathogenesis of a subgroup of patients with nonspecific chronic low back pain (CLBP). However, their association with clinical symptoms has not been studied in detail previously. METHODS: Sixty-two CLBP patients with a large M1 lesion were selected from CLBP patients who were sent for the first time for standard lumbar spine magnetic resonance imaging at a university hospital. To exclude other causes of CLBP, as far as possible, strict exclusion criteria were used: any specific back disease, even a slight nerve root compression, a recent or major spine operation, or age older than 65 years. The relative sizes of M1 and M2 lesions were visually estimated from sagittal images for comparison with clinical symptoms. RESULTS: The majority of patients (91.9%; 57 of 62) had an M1 lesion at a single level, 92% of the lesions being at L4-L5 or L5-S1 level. Forty-nine patients (79.0%) had a mixed M1-M2 lesion, and 13 (21.0%) had a pure M1 lesion. The mean of the pain intensity score was 6.2, and, correspondingly, the Oswestry Disability Index was 30.4. The mean relative sagittal area of the largest M1 lesion was 24.6% (SD = 16.2), and that of the M2 lesion was 10.9% (SD = 11.6). Neither the pain intensity nor the ODI scores were found to correlate with the largest relative size of the M1 lesion. The patients with "pure" M1 lesion had statistically significantly more clinical symptoms than patients having a mixed M1-M2 lesion. CONCLUSION: We conclude that the size of M1 lesion does not directly correlate with the clinical symptoms but that the type of Modic lesion is more important. This study supports the previous observations that when the inflammatory process turns to the mixed M1-M2 lesions, clinical symptoms decrease.

Relationship of Modic type 1 change with disc degeneration: a prospective MRI study.

OBJECTIVE: The objective was to study the natural course of Modic type 1 change (M1) in relation to lumbar disc degeneration. MATERIALS AND METHODS: Twenty-four chronic low back pain (LBP) patients with M1 on lumbar spine were selected from 1,015 patients with magnetic resonance imaging from a follow-up study lasting for 18-74 months. Exclusion criteria were any other specific back disorder, age >or=60 years, or a recent spine operation. The association between the development of M1 and degenerative disc changes was studied using multivariate modeling (complex samples logistic regression). RESULTS: At baseline, 20 of 28 (71%) disc spaces with M1 had a decreased disc height (DH) and 16 of 28 (57%) a dark nucleus pulposus, but ten of 28 (36%) a very dark annulus fibrosus and a paradoxically bright nucleus pulposus albeit decreased DH. During follow-up, DH decreased in 13 of 28 (46%) and signal intensity of nucleus pulposus (DSI) in eight of 28 (29%) disc spaces with M1, but it increased in four (14%) discs. In those without M1, only few changes occurred. The larger the M1, the more likely was the DH low or decreased further. Both the presence and changes in M1 were associated with a decrease in DH and changes in DSI and bulges. CONCLUSION: The degenerative process in discs with adjacent M1 seems to be accelerated and leads to advanced and deforming changes with special morphologic features. M1 may be a sign of a pathologic degenerative process in the discovertebral unit.

MRI follow-up of subchondral signal abnormalities in a selected group of chronic low back pain patients.

Subchondral signal abnormalities have been suggested to play an important role in chronic low back pain (LBP) syndromes. Their natural course is not well known. In this study the morphology and natural course of isolated subchondral signal abnormalities in the lumbosacral spine were analyzed with MRI. Twenty-four chronic LBP patients with a subchondral hypointensity on T1-weighted image (hyperintense on T2), indicating edema, were selected from a base population of 1,015 consecutive LBP patients to a follow-up MRI study within 18-72 months. Exclusion criteria were age >60 years, nerve root compression, a more specific back disease or a recent or major spine operation. The size and location of each subchondral signal abnormality and endplate lesion and the degree of degenerative disc changes were evaluated and compared between the baseline and follow-up studies. Most subchondral hypointensities were found at the L4/L5 or L5/S1 disc space, anteriorly and in both adjacent endplates. Almost all (53/54) hypointensities were associated with an endplate lesion. Twelve of the 54 subchondral hypointensities enlarged, six remained constant and 36 decreased or disappeared while five new ones appeared. Twenty-two (41%) hypointensities changed totally to hyperintensities or to mixed lesions. If the hypointensity increased, decreased or changed into hyperintensity, a change tended to develop in the adjacent endplate. If the hypointensity was absent or unchanged, endplate lesions did not tend to progress. In the absence of disc herniation or other specific spinal disease, subchondral hypointensities indicating edema are uncommon. They seem to have a highly variable course. There appears to be a link between endplate lesions and subchondral signal abnormalities. Further study is needed to explain the contribution of these findings to low back symptoms.

Ankle osteoarthritis is associated with knee osteoarthritis. Conclusions based on mechanical axis radiographs.

INTRODUCTION: Osteoarthritis (OA) of the ankle with an unknown etiology (primary OA) is rare, whereas a secondary OA due to a known cause is not uncommon. OA of the knee can, when it progresses, change the alignment of the whole extremity including the ankle joint. Since we had observed in patients coming for OA knee surgery coexisting OA in the ankle joint, our objective of this study was to assess the prevalence of abnormal alignment and degenerative changes in the ankle joint and to determine if degenerative changes in the knee and ankle correlated. These aims were assessed retrospectively, utilizing mechanical axis (MA) radiographs of subjects with knee OA prior to surgery. MATERIALS AND METHODS: This retrospective study consisted of 104 patients who had undergone surgery of the knee due to OA. A musculoskeletal radiologist and an orthopedic surgeon reviewed in consensus the preoperative and postoperative MA radiographs. We analyzed and measured the tibiofemoral (TF) angle, the mediolateral tibial translation, the deviation of the MA, the tilt of the talocrural joint and the degree of OA in the knee and ankle. RESULTS: The severity of OA of the TF joint correlated with the preoperative TF translation and moderately with the deviation of the MA and abnormal TF angle. Of the 104 patients, 30 showed coexisting OA of the ankle: the greater the tilt in the ankle, the more degenerative were the changes in the joint. The MA was corrected with surgery from a mean preoperative 5.4 degrees varus to a postoperative mean 1.2 degrees valgus, and the ankle tilt was changed significantly at the same time. CONCLUSION: Ankle OA and tilt were not uncommon in our patients with knee OA. The assumption that associations may exist between knee and ankle OA and joint malalignment was confirmed.