Bone marrow lesion and 5-year incident joint surgery in patients with knee osteoarthritis: a retrospective cohort study.

BACKGROUND: It is beneficial for society to discover the risk factors associated with surgery and to carry out some early interventions for patients with these risk factors. Few studies specifically explored the relationship between bone marrow lesions (BMLs) and long-term incident joint surgery. OBJECTIVE: To investigate the association between BML severity observed in knee osteoarthritis (OA) patients' first MRI examination and incident knee surgery within 5 years. Additionally, to assess the predictive value of BMLs for the incident knee surgery. DESIGN: Retrospective cohort study. METHODS: We identified patients diagnosed with knee OA and treated at our institution between January 2015 and January 2018, and retrieved their baseline clinical data and first MRI examination films from the information system. Next, we proceeded to determine the Max BML grades, BML burden grades and Presence BML grades for the medial, lateral, patellofemoral, and total compartments, respectively. Multi-variable logistic regression models examined the association of the BML grades with 5-year incident knee surgery. Positive and negative predictive values (PPVs and NPVs) were determined for BML grades referring to 5-year incident knee surgery. RESULTS: Totally, 1011 participants (knees) were found eligible to form the study population. Within the 5 years, surgery was performed on 74 knees. Max BML grade 2 and grade 3 of medial, patellofemoral and total compartments were strongly and significantly associated with incident surgery. None of the BML grades from lateral compartment was associated with incident surgery. The PPV was low and NPV was high for BMLs. CONCLUSIONS: BMLs found in the first MRI examination were associated with 5-year incident joint surgery, except for those allocated in lateral compartments. The high NPVs imply that patients without BMLs have a low risk of requiring surgery within 5 years.

Bone marrow edema of the knee: a narrative review.

Bone marrow edema (BME) is a frequent MRI finding in patients with knee pain. According to the etiology, BME of the knee can be classified into three main categories: ischemic, mechanic, and reactive. The diagnosis may be difficult, because of the specificity of symptoms and the poor radiographic findings. MRI is the gold standard, showing an area of altered signal of the bone with an high signal intensity on fat-suppressed, T2 weighted images, usually in combination with an intermediate or low signal intensity on T1 weighted images. Bone marrow edema tends to be self-limiting and, in most cases, resolves without any consequences in a varying amount of time. However, since it may evolve to complete joint destruction, early diagnosis and correct treatment are crucial to prevent the articular degeneration. Conservative therapy is the first step, with no weight-bearing for 3 to 6 weeks on the affected side, in combination with the administration of anti-inflammatory drugs or painkillers to manage symptoms. In non-responding forms and more advanced stages, minimally invasive preservative surgery can provide significant results, with subchondroplasty and core decompression being the two main procedures available. Knee arthroplasty, both total (TKA) or unicompartmental (UKA), is the only effective option when the degradation of cartilage is diffuse and in patients with subchondral bone collapse.

[The detecting value of virtual non-calcium technique of dual-energy CT for bone marrow edema around nontraumatic osteonecrosis of the femoral head].

Objective: To evaluate the value of virtual non-calcium (VNCa) technique of dual-energy CT (DECT) for detecting bone marrow edema (BME) around nontraumatic osteonecrosis of the femoral head (ONFH) using MRI as reference standard. Methods: Nontraumatic ONFH patients were prospectively studied in the Fourth Medical Center of Chinese PLA General Hospital from October 2022 to May 2023, and their MRI and DECT images were analyzed. The diagnostic efficiency of the subjective assessment of BME around ONFH by two radiologists in VNCa color-coded images were calculated using the MRI results as the reference standard. The BME ranges were compared between VNCa images and MRI. Traditional CT values and VNCa CT values were compared between normal bone marrow and BME. The receiver operator characteristic (ROC) curve was established based on the statistically different CT values, and the area under the curve (AUC) was calculated to find the threshold to distinguish normal bone marrow from BME and evaluate the diagnostic efficacy. Results: Thirty patients with ONFH were included, including 24 males and 6 females, aged (39±12) years. There were 18 bilateral hips and 12 unilateral hips, with a total of 48 hips, 34 hips of which showed BME on MRI. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy of subjective detection of BME on VNCa color coded maps by two physicians were 97.1% (33/34) and 97.1% (33/34), 92.9% (13/14) and 71.4% (10/14), 97.1% (33/34) and 89.2% (33/37), 92.9% (13/14) and 90.9% (10/11), 95.8% (46/48) and 89.6% (43/48), respectively, with no statistical difference (all P>0.05).There was no statistical difference between VNCa color-coded images and MRI in the BME range (P=1.160). The traditional CT values measured by the two radiologists were in good agreement with VNCa CT values, with intraclass correlation coefficient (ICC) of 0.948 (95%CI: 0.908-0.971) and 0.982 (95%CI: 0.969-0.990), respectively. The traditional CT value of normal bone marrow was (400.7±82.8) HU, and that of BME was (443.7±65.7) HU, with no statistical difference (P=0.062). The VNCa CT value of normal bone marrow was (-103.1±27.8) HU, and that of BME was (-32.9±25.7) HU, with statistical difference (P<0.001). The AUC of distinguishing normal bone marrow from BME based on VNCa CT value was 0.958 (95%CI: 0.857-0.995). The best cut-off value was -74.5 HU, and when the VNCa CT value was higher than -74.5 HU, the sensitivity, specificity, PPV, NPV and accuracy of diagnosing BME were 97.1%, 92.9%, 97.1%, 92.9% and 95.8 %, respectively. Conclusion: The VNCa technique of DECT has high efficiency in detecting BME around ONFH, and can accurately demonstrate the range of BME.

Differentiation of bone metastases from benign red marrow depositions: utilizing qualitative and quantitative analysis of conventional T1-weighted imaging and fat-suppressed T2-weighted imaging.

OBJECTIVES: To distinguish bone metastases (BMs) from benign red marrow depositions (BRMs) by qualitative and quantitative analyses of T1-weighted imaging and fat-suppressed T2-weighted imaging (T2 FS). METHODS: For 75 lesions including 38 BMs and 37 BRMs, two radiologists independently evaluated magnetic resonance images by qualitative (signal intensity [SI] of lesions compared to that of normal muscle [NM] or normal bone marrow [NBM]) and quantitative (parameters of the region of interests in the lesions, including T1 ratio [T1 SI ratio of lesion and NM], T2FMu ratio [T2 FS SI ratio of lesion and NM], and T2FMa ratio [T2 FS SI ratio of lesion and NBM]) analyses. RESULTS: Hyperintensity relative to NM or NBM on T2 FS was more frequent in BMs than in BRMs (100% vs 59.5%-78.4%, respectively; P ≤ 0.001) but also was present in more than half of BRMs. All quantitative parameters showed a significant difference between BMs and BRMs (T1 ratio, 1.075 vs 1.227 [P = 0.002]; T2FMu ratio, 2.094 vs 1.282 [P < 0.001]; T2FMa ratio, 3.232 vs 1.810 [P < 0.001]). The receiver operating characteristics areas under the curves of T2FMu and T2FMa ratios were clinically useful (0.781 and 0.841, respectively) and did not demonstrate statistically significant differences. CONCLUSIONS: The quantitative analysis of T2 FS facilitates distinguishing between BMs and BRMs, regardless of whether the reference was NM or NBM. ADVANCES IN KNOWLEDGE: Quantitative parameters derived from T2 FS facilitate differentiation of BMs BRMs without additional scans. The role of NBM as an internal standard for T2 FS to differentiate between BMs and BRMs is similar to that of NM.

Association between sacroiliac joint forms and subchondral changes in patients with Crohn's disease.

AIM: To assess the relationship between anatomical variants of sacroiliac joint (SIJ) and subchondral changes detected in magnetic resonance enterography (MRE) in patients with Crohn's disease (CD). METHODS: This was a retrospective study of 60 CD patients, who were divided into two groups: with (n = 16) and without SIJ (n = 44) involvement, depending on the presence of inflammatory (bone marrow edema) and structural changes (sclerosis and erosions) in MRE. Anatomical variants of SIJ were assessed in CT of the abdomen and/or pelvis, distinguishing typical form with convex iliac surface and atypical forms. Univariate and multivariate analyses were performed to reveal an association between joint changes and forms. RESULTS: Our study included 60 patients (38 males; mean age 38.72 years ± 13.33). Patients with SIJ changes were older (p = .044). No significant differences in CD localization and behavior were found. The most common SIJ lesions were structural changes (in 75% of patients); the main atypical form was the iliosacral complex. The univariate and multivariate analyses showed a significant association of atypical forms with total subchondral changes (odds ratio [OR]: 3.429, 95% confidence interval [CI] 1.043-11.268; p = .042; OR: 5.066, 95% CI: 1.273-20.167; p = .021, respectively), and with structural changes (OR: 4.185, 95% CI: 1.155-15.160; p = .029; OR: 5.986, 95% CI: 1.293-27.700; p = .022, respectively). CONCLUSION: Atypical forms of SIJ are a risk factor for the occurrence of structural joint changes in CD patients. An association between bone marrow edema and atypical forms was not found.

Characterization of bone marrow lesions in axial spondyloarthritis using quantitative T1 mapping MRI.

OBJECTIVE: Conventional magnetic resonance imaging (MRI) uses T1-weighted and short-tau inversion recovery (STIR) sequences to characterize bone marrow in axial spondyloarthritis. However, quantification is restricted to estimating the extent of lesions because signal intensities are highly variable both within individuals and across patients and MRI scanners. This study evaluates the performance of quantitative T1 mapping for distinguishing different types of bone marrow lesions of the sacroiliac joints. MATERIALS AND METHODS: In this prospective study, 62 patients underwent computed tomography (CT) and MRI of the sacroiliac joints including T1, STIR, and T1 mapping. Bone marrow lesions were characterized by three readers and assigned to one of four groups: sclerosis, osteitis, fat lesions, and mixed marrow lesions. Relaxation times on T1 maps were compared using generalized estimating equations and receiver operating characteristics (ROC) analysis. RESULTS: A total of 119 lesions were selected (sclerosis: 38, osteitis: 27, fat lesions: 40; mixed lesions: 14). T1 maps showed highly significant differences between the lesions with the lowest values for sclerosis (1516±220 ms), followed by osteitis (1909±75 ms), and fat lesions (2391±200 ms); p<0.001. T1 mapping differentiated lesions with areas under the ROC curve of 99% (sclerosis vs. osteitis) and 100% (other comparisons). CONCLUSION: T1 mapping allows accurate characterization of sclerosis, osteitis, and fat lesions at the sacroiliac joint but only for homogeneous, non-mixed lesions. Thus, further sequence development is needed before implementation in clinical routine.

Factors associated with trajectories of bone marrow lesions over 4 years: data from the Osteoarthritis Initiative.

OBJECTIVE: To identify bone marrow lesion (BML) trajectories over 4 years and their demographic and structural predictors in middle-aged and older adults with or at increased risk of knee osteoarthritis (OA). METHODS: A total of 614 participants (mean age 61 years, 62% female) from the Osteoarthritis Initiative cohort (OAI) were included. BMLs in 15 anatomical locations of the knee were measured annually from baseline to 4 years using the Magnetic Resonance Imaging Osteoarthritis Knee Score (MOAKS) method. BML trajectories were determined using latent class mixed models (LCMMs). Multinomial logistic regression was used to examine baseline characteristics that predicted BML trajectories. RESULTS: Three distinct BML trajectories were identified: "Mild-stable BMLs" (25.9%), "Moderate-stable BMLs" (66.4%), and "Rapid-rise BMLs" (7.7%). Compared to the "Mild-stable BMLs" trajectory, current smokers were more likely to be in the "Moderate-stable BMLs" (odds ratio [OR] 2.089, P < 0.001) and "Rapid-rise" (OR 2.462, P < 0.001) trajectories. Moreover, female sex and meniscal tears were associated with an increased risk of being in the "Rapid-rise BMLs" trajectory (OR 2.023 to 2.504, P < 0.05). Participants who had higher education levels and drank more alcohol were more likely to be in the "Rapid-rise BMLs" trajectory (OR 1.624 to 3.178, P < 0.05) and less likely to be in the "Moderate-stable BMLs" trajectory (OR 0.668 to 0.674, P < 0.05). CONCLUSIONS: During the 4-year follow-up, most participants had relatively stable BMLs, few had enlarged BMLs, and no trajectory of decreased BMLs was identified. Sociodemographic factors, lifestyle, and knee structural pathology play roles in predicting distinct BML trajectories.

Association of anatomical variants of the sacroiliac joint with bone marrow edema in patients with axial spondyloarthritis.

OBJECTIVE: To determine the prevalence of sacroiliac joint variants in patients with axial spondyloarthritis (axSpA) using MRI-based synthetic CT images and to evaluate their relationships with the presence of bone marrow edema, as this may potentially complicate diagnosing active sacroiliitis on MRI in patients with suspected axSpA. METHODS: 172 patients were retrospectively included. All patients underwent MRI because of clinical suspicion of sacroiliitis. The diagnosis of axSpA was made by a tertiary hospital rheumatologist. Two readers independently determined the presence of bone marrow edema and the presence of one or more of the nine known sacroiliac joint (SIJ) variants. RESULTS: SIJ variants were common in axSpA patients (82.9%) and the non-SpA group (85.4%); there were no significant differences in prevalence. Bone marrow edema was frequently found in axSpA (86.8%) and non-SpA patients (34%). AxSpA patients with SIJ variants (except for accessory joint) demonstrated 4 to 10 times higher odds for bone marrow edema, however not statistically significant. The more variants were present in this group, the higher the chance of bone marrow edema. However, some multicollinearity cannot be excluded, since bone marrow edema is very frequent in the axSpA group by definition. CONCLUSION: SIJ variants are common in axSpA and non-SpA patients. SIJ variants were associated with higher prevalence of bone marrow edema in axSpA patients, potentially due to altered biomechanics, except for accessory joint which may act as a stabilizer.

Foot and Ankle Bone Marrow Edema Assessment in Long Distance Runners.

BACKGROUND: The clinical significance of foot and ankle bone marrow edema (BME) is poorly understood. METHODS: Magnetic resonance imaging (MRI) and the visual analog scale (VAS) pain scores were collected for 17 runners who participated in the Twin Cities Marathon, immediately postmarathon and at a 6-week follow-up. Bone marrow edema lesions were classified using lesion frequency, anatomical location, and grading scale change to calculate a BME score for each affected bone. Spearman rank correlation coefficient test was used to identify a possible correlation between VAS and postmarathon BME. A paired Student t test was used to detect differences between total mileage ran 6 weeks postmarathon in participants with or without BME. RESULTS: After completing the marathon, 8 BME lesions were identified in 5 participants (29.4%; 5/17), 3 were men, and 2 were women, with a mean age of 33.8 years (range: 24-52), and BMI of 22.9 ± 4. All lesions were resolved on 6-week follow-up imaging. VAS pain scores did not correlate with postmarathon BME. A significant difference in total miles logged over 6 weeks postmarathon could not be found among participants with and without BME. CONCLUSION: Foot and ankle BME changes identified by MRI were not correlated to clinical symptoms and may resolve with self-directed activity in less time than other areas of the lower extremity. LEVEL OF EVIDENCE: Level II, Prospective Cohort Study.

Diagnostic accuracy of dual-energy CT for bone marrow edema in patients with acute knee injury: a systematic review and meta-analysis.

BACKGROUND: Knee injuries are prevalent, and early diagnosis is crucial for guiding clinical therapy. MRI is the diagnostic gold standard for bone marrow edema (BME) in patients with acute knee injuries, yet there are still limitations. Dual-energy CT, a possible viable replacement, is being explored (DECT). METHODS: We systematically retrieved studies from EMBASE, Scopus, PUBMED, and the Cochrane Library and collected gray literatures. In accordance with the PRISMA-DTA standards, a systematic review was conducted between the study's initiation and July 31, 2021, utilizing an MRI reference standard and at least 10 adult patients with acute knee injuries to evaluate the diagnostic effectiveness of DECT for diagnosing BME. Two reviewers collected the study's details independently. For the meta-analysis, a bivariate mixed-effects regression model was utilized, and subgroup analysis was employed to determine the sources of variability. RESULTS: The research included nine studies that examined 290 individuals between the ages of 23 and 53 with acute knee injuries who had DECT and MRI. Overall, the sensitivity, specificity, and AUC of the BME were 85% (95% confidence interval [CI]: 77-90%), 96% (95% CI: 93-97%), and 0.97 (95% CI: 0.95-0.98), respectively. To account for the assumed diversity of research, there were no statistically significant differences between the comparison groups in terms of specificity and sensitivity. CONCLUSION: DECT is a viable alternative to MRI for individuals with acute knee injuries when MRI is inappropriate or unavailable.

Machine Learning Pipeline for Predicting Bone Marrow Edema Along the Sacroiliac Joints on Magnetic Resonance Imaging.

OBJECTIVE: We aimed to develop and validate a fully automated machine learning (ML) algorithm that predicts bone marrow edema (BME) on a quadrant level in sacroiliac (SI) joint magnetic resonance imaging (MRI). METHODS: A computer vision workflow automatically locates the SI joints, segments regions of interest (ilium and sacrum), performs objective quadrant extraction, and predicts presence of BME, suggestive of inflammatory lesions, on a quadrant level in semicoronal slices of T1/T2-weighted MRI scans. Ground truth was determined by consensus among human readers. The inflammation classifier was trained using a ResNet18 backbone and five-fold cross-validated on scans of patients with spondyloarthritis (SpA) (n = 279), postpartum individuals (n = 71), and healthy subjects (n = 114). Independent SpA patient MRI scans (n = 243) served as test data set. Patient-level predictions were derived from aggregating quadrant-level predictions, ie, at least one positive quadrant. RESULTS: The algorithm automatically detects the SI joints with a precision of 98.4% and segments ilium/sacrum with an intersection over union of 85.6% and 67.9%, respectively. The inflammation classifier performed well in cross-validation: area under the curve (AUC) 94.5%, balanced accuracy (B-ACC) 80.5%, and F1 score 64.1%. In the test data set, AUC was 88.2%, B-ACC 72.1%, and F1 score 50.8%. On a patient level, the model achieved a B-ACC of 81.6% and 81.4% in the cross-validation and test data set, respectively. CONCLUSION: We propose a fully automated ML pipeline that enables objective and standardized evaluation of BME along the SI joints on MRI. This method has the potential to screen large numbers of patients with (suspected) SpA and is a step closer towards artificial intelligence-assisted diagnosis and follow-up.

Bone marrow edema in the sacroiliac joints is associated with the development of structural lesions at the same anatomical location over time in patients with axial spondyloarthritis.

OBJECTIVE: To assess whether the presence of bone marrow edema (BME) leads to the development of structural lesions at the same anatomical location of the sacroiliac joints (SIJ), and to investigate the association between BME patterns over time and structural lesions in patients with early axial spondyloarthritis (axSpA). METHODS: Patients with axSpA from the DESIR cohort with ≥2 consecutive magnetic resonance imaging (MRI)-SIJ were assessed at baseline, 2 and 5 years. MRI-SIJ images were divided into 8 quadrants. The association between BME and subsequent structural lesions (sclerosis, erosions, fatty lesions, and ankylosis) on MRI in the same quadrant was tested longitudinally. Additionally, patients were grouped according to the pattern of BME evolution across quadrants over time (no BME, sporadic, fluctuating, and persistent). The association between these patterns and 5-year imaging outcomes (eg: ≥5 erosions and/or fatty lesions on MRI-SIJ) was tested. RESULTS: In total, 196 patients were included. BME in each quadrant was associated with sclerosis (OR:1.9 (95%CI: 1.1;3.4)), erosions (1.9 (1.5;2.5)) and fatty lesions (1.9 (1.4;2.6)). Ankylosis was uncommon. There was a gradient between increased level of inflammation and subsequent damage: compared to the 'no BME' pattern, the sporadic (OR (95% CI): 2.1 (1.0;4.5)), fluctuating (OR:5.6(2.2;14.4)) and persistent (OR:7.5(2.8;19.6)) patterns were associated with higher structural damage on MRI-SIJ at 5-years. CONCLUSIONS: In early axSpA, inflammation on MRI-SIJ leads to damage at the quadrant level. The higher the exposure to inflammation across quadrants in the SIJs over time the higher the likelihood of subsequent structural damage, suggesting a cumulative effect.

[Study on the relationship between severe knee osteoarthritis and bone marrow edema].

OBJECTIVE: To investigate the relationship between bone marrow edema and pathological changes, symptoms and signs of severe knee osteoarthritis. METHODS: From January 2020 to March 2021, 160 patients with severe knee osteoarthritis who underwrent MRI of the knee at the Department of Bone and Joint, Wangjing Hospital, China Academy of Chinese Medical Sciences were included. Eighty patients with bone marrow edema were selected as the case group, including 12 males and 68 females, aged from 51 to 80 years old with an average of (66.58±8.10) years old, the duration of disease 5 to 40 months with an average of (15.61±9.25) months. Eighty patients without bone marrow edema were selected as the control group, including 15 males and 65 females, aged from 50 to 80 years old with an average of (67.82±8.05) years old, the duration of disease 6 to 37 months with an average of (15.75±8.18) months, BMI was (28.26±3.13) kg·m-2 ranged from 21.39 to 34.46 kg·m-2. The degree of bone marrow edema was evaluated by knee whole oragan magnetic resonance imaging score (WORMS). The degree of knee osteoarthritis was evaluated by Kellgren- Lawrence(K-L) grade and Western Ontario and McMaster University Osteoarthritis Index (WOMAC). The degree of joint pain was evaluated by visual analogue scale(VAS) and WOMAC pain score, the joint signs were evaluated by tenderness, percussion pain, joint swelling and joint range of motion. To explore the relationship between bone marrow edema and knee osteoarthritis, the prevalence of bone marrow edema and K-L grade were compared between the two groups. Furthermore the WORMS score and WOMAC index, pain-related score, and sign-related score correlation coefficient were analyzed to further explore the relationship between bone marrow edema and knee osteoarthritis index, joint pain symptoms and signs. RESULTS: There was 68.75% (55/80) of the patients in the case group were in K-L grade Ⅳ, and 52.5% (42/80) in the control group, indicating a higher proportion of patients with grade Ⅳ in the case group than the control group (χ2=4.425, P<0.05). In the case group, there was a strong correlation between bone marrow edema WORMS score and knee osteoarthritis WOMAC index. (r=0.873>0.8, P<0.001), a moderate correlation between WORMS score and VAS score and WOMAC pain score(r=0.752, 0.650>0.5, P<0.001), a moderate correlation between WORMS score and percussion pain score (r=0.784>0.5, P<0.001), and a weak correlation between WORMS score and VAS and tenderness score, joint swelling score and joint range of motion score (r=0.194, 0.259, 0.296<0.3, P<0.001). CONCLUSION: Our study suggests that severe knee osteoarthritis is associated with an increased risk of bone marrow edema. Bone marrow edema can also lead to knee osteoarthritis joint pain, with percussion pain being a positive sign, but tenderness, joint swelling and limitation of activity are not significantly related to bone marrow edema.

Spontaneous Bone Marrow Edema: Perfusion Abnormalities and Treatment with Surgical Decompression.

Bone marrow edema (BME), also termed bone marrow lesions, is a syndrome characterized by bone pain and the appearance of high signal intensity on T2 fat-suppressed and short tau inversion recovery (STIR) MRI sequences. BME can be related to trauma or a variety of non-traumatic diseases, and current treatment modalities include non-steroidal anti-inflammatory drugs (NSAIDS), bisphosphonates, denosumab, extracorporeal shockwave therapy (ESWT), the vasoactive prostacyclin analogue iloprost, and surgical decompression. Spontaneous BME is a subset that has been observed with no apparent causative conditions. It is most likely caused by venous outflow obstruction and intraosseous hypertension. These are mechanistically related to impaired perfusion and ischemia in several models of BME and are related to bone remodeling. The association of perfusion abnormalities and bone pain provides the pathophysiological rationale for surgical decompression. We present a case of spontaneous BME and a second case of spontaneous migratory BME treated with surgical decompression and demonstrate resolution of pain and the high signal intensity on MRI. This report provides an integration of the clinical syndrome, MR imaging characteristics, circulatory pathophysiology, and treatment. It draws upon several studies to suggest that both the bone pain and the MRI characteristics are related to venous stasis, and when circulatory pathologies are relieved by decompression or fenestration, both the bone pain and the MRI signal abnormalities resolve.

[Study on correlation between bone marrow edema and osteoporosis in patients with severe knee osteoarthritis].

OBJECTIVE: To explore relationship between bone marrow edema(BME) and osteoporosis in patients with severe knee osteoarthritis. METHODS: Unmatched case-control study was conducted. Totally 160 patients with severe knee osteoarthritis who had undergone knee magnetic resonance imaging (MRI) and bone mineral density examination (BMD) from January 2020 to March 2021 were included. Eighty patients complicated with BME were included in BME group, and 80 patients without BME were selected as NBME group. In BME group, there were 12 males and 68 females, aged from 51 to 80 years old with an average of(66.58±8.10) years old;the courses of disease ranged from 5 to 40 months with an average of (15.61±9.25) months;body mass index(BMI) ranged from 21.81 to 34.70 with an average of (27.79±3.00) kg·m-2;25 patients classified to grade Ⅲ and 55 patients grade Ⅳ according to Kellgren- Lawrence(K-L). In NBME group, there were 15 males and 65 females, aged from 50 to 80 years old with an average of(67.82±8.05) years old;the course of disease ranged from 6 to 37 months with an average of(15.75±8.18) months;BMI ranged from 21.39 to 34.46 with an average of (28.26±3.13) kg·m-2;25 patients were K-L Ⅲ and 55 patients with K-L Ⅳ. The degree of bone marrow edema was evaluated by knee whole oragan magnetic resonance imaging score(WORMS). Osteoporosis was diagnosed and BMD was evaluated by DXA T value. To explore the relationship between bone marrow edema and osteoporosis by comparing prevalence rate of osteoporosis between two groups, and to further explore relationship between BME and BMD by Spearman correlation analysis of BME WORMS score and DXA T value in BME group. RESULTS: The complete case data were obtained on the first diagnosis, and there was no significant difference in sex, age, courses of disease and BMI between two groups (P>0.05). The proportion of K-L Ⅳ in BME group was significantly higher than that in NBME (P<0.05). The prevalence rate of osteoporosis in BME group was significantly higher than in NBME group with the same K-L grade (P<0.001), and there was a strong negative correlation between BME WORMS score and DXA BMD T value (r=-0.812, |r|=0.812 >0.8, P<0.001). CONCLUSION: Osteoporosis is one of the risk factors of bone marrow edema in patients with severe knee osteoarthritis, and the lower the bone mineral density is, the easier it is to be complicated with bone marrow edema.

Can radiomics replace the SPARCC scoring system in evaluating bone marrow edema of sacroiliac joints in patients with axial spondyloarthritis?

OBJECTIVES: To develop an objective and efficient method based on radiomics to evaluate bone marrow edema (BMO) of sacroiliac joints (SIJs) by magnetic resonance imaging (MRI) in patients with axial spondyloarthritis (axSpA) and to compare with the Spondyloarthritis Research Consortium of Canada (SPARCC) scoring system. METHODS: From September 2013 to March 2022, patients with axSpA who underwent 3.0T SIJ-MRI were included and were randomly divided into training and validation cohorts at a ratio of 7:3. The optimal radiomics features selected from the SIJ-MRI in the training cohort were included to generate the radiomics model. The performance of the model was evaluated by ROC analysis and decision curve analysis (DCA). Rad scores were calculated using the radiomics model. The responsiveness was compared for Rad scores and SPARCC scores. We also assessed the correlation between the Rad score and SPARCC score. RESULTS: A total of 558 patients were finally included. The radiomics model showed favorable discrimination of a SPARCC score <2 or ≥2 both in the training (AUC, 0.90; 95% CI: 0.87-0.93) and validation cohorts (AUC, 0.90; 95% CI, 0.86-0.95). DCA confirmed that the model was clinically useful. Rad score showed higher responsiveness to treatment-related change than SPARCC score. Furthermore, a significant correlation was noted between the Rad score and SPARCC score when scoring the status of BMO (rs=0.80, P < 0.001), and a strong correlation was noted when scoring the change in BMO (r=0.70, P < 0.001). CONCLUSION: The study proposed a radiomics model to accurately quantify the BMO of SIJs in patients with axSpA, providing an alternative to the SPARCC scoring system. Key Points • The Rad score is an index with high validity for the objective and quantitative evaluation of bone marrow edema (BMO) of the sacroiliac joints in axial spondyloarthritis. • The Rad score is a promising tool to monitor the change of BMO upon treatment.

Intermediate-weighted MRI with fat suppression (IW-FS): diagnostic performance for bone marrow edema and erosion detection in axial spondyloarthritis.

BACKGROUND: Bone marrow edema (BME) and erosion of the sacroiliac joint are both key lesions for diagnosing axial spondyloarthritis (axSpA) on magnetic resonance imaging (MRI). PURPOSE: To qualitatively and quantitatively compare intermediate-weighted MRI with fat suppression (IW-FS) with T2-weighted short tau inversion recovery (T2-STIR) in assessment of sacroiliac BME and erosion in axSpA. MATERIAL AND METHODS: Patients aged 18-60 years with axSpA were prospectively enrolled. All patients underwent a 3.0-T MRI examination of the sacroiliac joints. Para-coronal IW-FS, T2-STIR, and T1-weighted (T1W) images were acquired. BME and erosion were scored by two readers in consensus on IW-FS and STIR using a modified Spondyloarthritis Research Consortium of Canada (SPARCC) scoring system. Consensus scores on T1WI were used as the reference for erosion. Signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were measured for BME. RESULTS: In total, 49 patients (mean age=33.4 ± 7.6 years) were included. More patients were scored as having BME on T2-STIR (36 vs. 29, P = 0.016). SPARCC-BME score on IW-FS was lower than that acquired on T2-STIR (mean, 11.5 vs. 14.7, P = 0.002). SNR and CNR of BME were both lower on IW-FS than on T2-STIR (mean SNR, 118 vs. 218, P < 0.001; mean CNR, 44 vs. 137, P < 0.001). The sensitivity of erosion detection was higher on IW-FS (83%) than on T2-STIR (54%, P = 0.006). CONCLUSION: IW-FS is not sufficient for BME detection using T2-STIR as the reference standard in patients with axSpA. IW-FS has a much higher sensitivity than T2-STIR for erosion detection in the sacroiliac joint.

Extensor carpi ulnaris tendon pathology and ulnar styloid bone marrow edema as diagnostic markers of peripheral triangular fibrocartilage complex tears on wrist MRI: a case-control study.

OBJECTIVES: To evaluate extensor carpi ulnaris (ECU) tendon pathology and ulnar styloid process bone marrow edema (BME) as diagnostic MRI markers for peripheral triangular fibrocartilage complex (TFCC) tears. METHODS: One hundred thirty-three patients (age range 21-75, 68 females) with wrist 1.5-T MRI and arthroscopy were included in this retrospective case-control study. The presence of TFCC tears (no tear, central perforation, or peripheral tear), ECU pathology (tenosynovitis, tendinosis, tear or subluxation), and BME at the ulnar styloid process were determined on MRI and correlated with arthroscopy. Cross-tabulation with chi-square tests, binary logistic regression with odds ratios (OR), and sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were used to describe diagnostic efficacy. RESULTS: On arthroscopy, 46 cases with no TFCC tear, 34 cases with central perforations, and 53 cases with peripheral TFCC tears were identified. ECU pathology was seen in 19.6% (9/46) of patients with no TFCC tears, in 11.8% (4/34) with central perforations and in 84.9% (45/53) with peripheral TFCC tears (p < 0.001); the respective numbers for BME were 21.7% (10/46), 23.5% (8/34), and 88.7% (47/53) (p < 0.001). Binary regression analysis showed additional value from ECU pathology and BME in predicting peripheral TFCC tears. The combined approach with direct MRI evaluation and both ECU pathology and BME yielded a 100% positive predictive value for peripheral TFCC tear as compared to 89% with direct evaluation alone. CONCLUSIONS: ECU pathology and ulnar styloid BME are highly associated with peripheral TFCC tears and can be used as secondary signs to diagnose tears. KEY POINTS: • ECU pathology and ulnar styloid BME are highly associated with peripheral TFCC tears and can be used as secondary signs to confirm the presence of TFCC tears. • If there is a peripheral TFCC tear on direct MRI evaluation and in addition both ECU pathology and BME on MRI, the positive predictive value is 100% that there will be a tear on arthroscopy compared to 89% with direct evaluation alone. • If there is no peripheral TFCC tear on direct evaluation and neither ECU pathology nor BME on MRI, the negative predictive value is 98% that there will be no tear on arthroscopy compared to 94% with direct evaluation alone.

Extent of bone marrow edema on dual-energy CT aids in differentiation of acute from post-acute fractures of lower legs.

OBJECTIVES: Bone marrow edema (BME) from dual-energy CT is useful to direct attention to radiographically occult fractures. The aim was to characterize utility of BME of lower extremity (LE) fractures with the hypothesis that stabilized and post-acute fractures exhibit decreased extent and frequency of BME than non-stabilized and acute fractures, respectively. METHODS: An IRB-approved retrospective review of known LE fractures. A total of 141 cases met inclusion criteria, including 82 fractures without splint/cast stabilization, and 59 cases with stabilization. Two readers independently recorded BME, and its multiplicity and area (mm2). A separate reader assessed fracture location, comminution, and chronicity. Wilcoxon rank sum test, multiple regression, intraclass correlation (ICC), kappa statistics, and chi-square tests were used. RESULTS: BME was significantly larger in non-stabilized (859.3 mm2 (420.6-1451.8)) than stabilized fractures (493.5 mm2 (288.8-883.2)), p = .011). Comminuted (p = 0.006), non-stabilized (p = 0.0004), and acute fractures (p = 0.036) were all associated with larger BME area. BME presence had excellent results for both stabilized (Cohen's Kappa = 0.81) and non-stabilized fractures (Cohen's Kappa = 0.84). ICC for BME area showed excellent correlation for both stabilized (ICC = 0.78) and non-stabilized groups (ICC = 0.86). BME multiplicity showed excellent agreement for stabilized (ICC = 0.81) and good agreement for non-stabilized (ICC = 0.67) fractures. Lastly, stabilized cases showed increased multiplicity of BME compared to non-stabilized fractures (p < 0.001). CONCLUSIONS: BME evaluation can assist in differentiation of acute versus post-acute fractures. Extent of BME is reduced with splint/cast stabilization, which may limit its accuracy in detection of lower extremity fractures. KEY POINTS: • Evaluation of bone marrow edema on dual-energy CT aids in differentiation of acute versus post-acute fracture. • Bone marrow edema evaluation is limited in the setting of post-acute or stabilized fractures. • There is decreased frequency and extent of bone marrow edema in post-acute, non-comminuted, and stabilized fractures.