Association of Preoperative Subchondral Bone Marrow Oedema with Outcomes after Lateral Unicompartmental Knee Arthroplasty.

OBJECTIVE: To determine whether the presence of preoperative subchondral bone marrow oedema (SBME) is associated with inferior outcomes after lateral unicompartmental knee arthroplasty (LUKA). STUDY DESIGN: Descriptive study. Place and Duration of the Study: Department of Orthopaedic Surgery, Chongqing Orthopaedic Hospital of Traditional Chinese Medicine, Chongqing, China, from January 2019 to June 2022. METHODOLOGY: Data on patients treated with LUKA were obtained from the Medical Registry Database. Two groups were made based on the presence and absence of SBME on preoperative magnetic resonance imaging (MRI). The visual analogue scale (VAS), American Knee Society Scores (AKSS), and rate of patient satisfaction were compared between the two groups. RESULTS: A total of 20 patients treated with LUKA were reviewed. The SBME was present in 9 cases and absent in 11 cases. Patients with SBME had inferior scores at preoperative evaluation and at 1, 3, and 6 months postoperatively. However, there was no significant difference between the groups at the 12-month follow-up. Eight (88.9%) patients with SBME were satisfied with the LUKA surgery versus 9 (81.8%) patients without SBME, showing no significant differences between groups. CONCLUSION: Presence of preoperative SBME is associated with inferior functional outcomes after LUKA within six months of follow-up. KEY WORDS: Bone marrow, Oedema, Knee, Arthroplasty, Outcome, Patient satisfaction.

Combating bone marrow failure with polymer materials.

Bone marrow failure (BMF) has become one of the most studied autoimmune disorders, particularly due to its prevalence both as an inherited disease, but also as a result of chemotherapies. BMF is associated with severe symptoms such as bleeding episodes and susceptibility to infections, and often has underlying characteristics, such as anemia, thrombocytopenia, and neutropenia. The current treatment landscape for BMF requires stem cell transplantation or chemotherapies to induce immune suppression. However, there is limited donor cell availability or dose related toxicity associated with these treatments. Optimizing these treatments has become a necessity. Polymer-based materials have become increasingly popular, as current research efforts are focused on synthesizing novel cell matrices for stem cell expansion to solve limited donor cell availability, as well as applying polymer delivery vehicles to intracellularly deliver cargo that can aid in immunosuppression. Here, we discuss the importance and impact of polymer materials to enhance therapeutics in the context of BMF.

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.

Predictive value of TCM tongue characteristics for chemotherapy-induced myelosuppression in patients with lung cancer.

This study aimed to investigate the clinical predictors, including traditional Chinese medicine tongue characteristics and other clinical parameters for chemotherapy-induced myelosuppression (CIM), and then to develop a clinical prediction model and construct a nomogram. A total of 103 patients with lung cancer were prospectively enrolled in this study. All of them were scheduled to receive first-line chemotherapy regimens. Participants were randomly assigned to either the training group (n = 52) or the test group (n = 51). Tongue characteristics and clinical parameters were collected before the start of chemotherapy, and then the incidence of myelosuppression was assessed after treatment. We used univariate logistic regression analysis to identify the risk predictors for assessing the incidence of CIM. Moreover, we developed a predictive model and a nomogram using multivariate logistic regression analysis. Finally, we evaluated the predictive performance of the model by examining the area under the curve value of the receiver operating characteristic, calibration curve, and decision curve analysis. As a result, a total of 3 independent predictors were found to be associated with the CIM in multivariate regression analysis: the fat tongue (OR = 3.67), Karnofsky performance status score (OR = 0.11), and the number of high-toxic drugs in chemotherapy regimens (OR = 4.78). Then a model was constructed using these 3 predictors and it exhibited a robust predictive performance with an area under the curve of 0.82 and the consistent calibration curves. Besides, the decision curve analysis results suggested that applying this predictive model can result in more net clinical benefit for patients. We established a traditional Chinese medicine prediction model based on the tongue characteristics and clinical parameters, which could serve as a useful tool for assessing the risk of CIM.

HLA-haploidentical stem cell transplantation in children with inherited bone marrow failure syndromes: A retrospective analysis on behalf of EBMT severe aplastic Anemia and pediatric diseases working parties.

Haploidentical stem cell transplantation (haplo-SCT) represents the main alternative for children with inherited bone marrow failure syndrome (I-BMF) lacking a matched donor. This retrospective study, conducted on behalf of the EBMT SAAWP and PDWP, aims to report the current outcomes of haplo-SCT in I-BMFs, comparing the different in vivo and ex vivo T-cell depletion approaches. One hundred and sixty-two I-BMF patients who underwent haplo-SCT (median age 7.4 years) have been registered. Fanconi Anemia was the most represented diagnosis (70.1%). Based on different T-cell depletion (TCD) approaches, four categories were identified: (1) TCRαß+/CD19+-depletion (43.8%); (2) T-repleted with post-transplant Cyclophosphamide (PTCy, 34.0%); (3) In-vivo T-depletion with ATG/alemtuzumab (14.8%); (4) CD34+ positive selection (7.4%). The cumulative incidences (CI) of neutrophil and platelet engraftment were 84% and 76% respectively, while that of primary and secondary graft failure was 10% and 8% respectively. The 100-day CI of acute GvHD grade III-IV(95% CI) was 13%, while the 24-month CI of extensive chronic GvHD was 4%. After a median follow-up of 43.4 months, the 2-year overall survival(OS) and GvHD/Rejection-free Survival (GRFS) probabilities are 67% and 53%, respectively. The TCR CD3+αß+/CD19+ depletion group showed a significantly lower incidence of both acute and chronic GvHD and higher OS (79%; p0.013) and GRFS (71%; p < .001), while no significant differences in outcomes have been observed by different diagnosis and conditioning regimens. This large retrospective study supports the safety and feasibility of haplo-SCT in I-BMF patients. TCRαß+/CD19+ depletion offers higher chances of patients' survival, with a significantly lower risk of severe a- and c-GvHD in I-BMFs compared to other platforms.

Gilteritinib combined with venetoclax and azacitidine for relapsed acute myeloid leukemia cocurrent with pure red cell aplasia after allogeneic hematopoietic stem cell transplantation: a case report.

Pure red cell aplasia (PRCA) is a rare bone marrow (BM) disorder characterized by ineffective erythropoiesis, reduced reticulocyte count, normocytic anemia, and the absence of erythroid precursors. Here, we present a rare instance of PRCA occurring after ABO-matched allo-HSCT in a refractory/relapsed acute myeloid leukemia (R/R AML) patient. In this case, the patient received a combination treatment of Gilteritinib, Venetoclax, and Azacitidine. Remarkably, this treatment not only reduced myeloblasts but also facilitated the restoration of erythroid hematopoiesis.

Can 18F-FES PET Improve the Evaluation of 18F-FDG PET in Patients With Metastatic Invasive Lobular Carcinoma?

PURPOSE: Invasive lobular carcinoma (ILC) exhibits a low affinity for 18F-FDG. The estrogen receptor (ER) is commonly expressed in ILCs, suggesting a potential benefit of targeting with the ER probe 18F-FES in this patient population. The objective of this study was to evaluate the diagnostic performance of 18F-FES imaging in patients with metastatic ILC and compare it with that of 18F-FDG. METHODS: We conducted a retrospective analysis of 20 ILC patients who underwent concurrent 18F-FES and 18F-FDG PET/CT examinations in our center. 18F-FES and 18F-FDG imaging were analyzed to determine the total count of tracer-avid lesions in nonbone sites and their corresponding organ systems, assess the extent of anatomical regions involved in bone metastases, and measure the SUVmax values for both tracers. RESULTS: Among 20 ILC patients, 65 nonbone lesions were found to be distributed in 13 patients, and 16 patients were diagnosed with bone metastasis, which was distributed in 54 skeletal anatomical regions. The detection rate of 18F-FDG in nonbone lesions was higher than that of 18F-FES (57 vs 37, P < 0.001). 18F-FES demonstrated a superior ability to detect nonbone lesions in 4 patients, whereas 18F-FDG was superior in 5 patients (P > 0.05). Among 9/16 patients with bone metastasis, 18F-FES demonstrated a significant advantage in the detection of bone lesions compared with 18F-FDG (P = 0.05). Furthermore, patients with only 18F-FES-positive lesions (12/12) were administered endocrine regimens, whereas patients lacking 18F-FES uptake (2/3) predominantly received chemotherapy. CONCLUSIONS: 18F-FES is more effective than 18F-FDG in detecting bone metastasis in ILC, but it does not demonstrate a significant advantage in nonbone lesions. Additionally, the results of examination with 18F-FES have the potential to guide patient treatment plans.

A Rare Inherited Bone Marrow Failure Syndrome Disclosed by Reanalysis of the Exome Data of a Patient Evaluated for Cytopenia and Dysmorphic Features.

BACKGROUND: Multisystemic findings of inherited bone marrow failure syndromes may cause difficulty in diagnosis. Exome sequencing (ES) helps to define the etiology of rare diseases and reanalysis offers a valuable new diagnostic approach. Herein, we present the clinical and molecular characteristics of a girl who was referred for cytopenia and frequent infections. CASE REPORT: A 5-year-old girl with cytopenia, dysmorphism, short stature, developmental delay, and myopia was referred for genetic counseling. Reanalysis of the ES data revealed a homozygous splice-site variant in the DNAJC21 (NM_001012339.3:c.983+1G>A), causing Shwachman-Diamond Syndrome (SDS). It was shown by the RNA sequencing that exon 7 was skipped, causing an 88-nucleotide deletion. CONCLUSIONS: Precise genetic diagnosis enables genetic counseling and improves patient management by avoiding inappropriate treatment and unnecessary testing. This report would contribute to the clinical and molecular understanding of this rare type of SDS caused by DNAJC21 variants and expand the phenotypic features of this condition.

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.

Myelodysplastic neoplasms evolving from inherited bone marrow failure syndromes / germline predisposition syndromes: Back under the microscope.

Inherited bone marrow failure syndromes and germline predisposition syndromes (IBMFS/GPS) are associated with increased risk for hematologic malignancies, particularly myeloid neoplasms, such as myelodysplastic neoplasms (MDS) and acute myeloid leukemia (AML). The diagnosis of MDS in these syndromes poses difficulty due to frequent bone marrow hypocellularity and the presence of some degree of dysplastic features related to the underlying germline defect causing abnormal maturation of one or more cell lines. Yet, the diagnosis of MDS is usually associated with a worse outcome in several IBMFS/GPS. Criteria for the diagnosis of MDS in IBMFS/GPS have not been standardized with some authors suggesting a mixture of morphologic, cytogenetic, and genetic criteria. This review highlights these challenges and suggests a more standardized approach to nomenclature and diagnostic criteria.

[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.

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.

Dual-energy CT applications in musculoskeletal disorders.

Dual-energy CT (DECT) is an exciting application in CT technology conferring many advantages over conventional single-energy CT at no additional with comparable radiation dose to the patient. Various emerging and increasingly established clinical DECT applications in musculoskeletal (MSK) imaging such as bone marrow oedema detection, metal artefact reduction, monosodium urate analysis, and collagen analysis for ligamentous, meniscal, and disc injuries are made possible through its advanced DECT post-processing capabilities. These provide superior information on tissue composition, artefact reduction and image optimization. Newer DECT applications to evaluate fat fraction for sarcopenia, Rho/Z application for soft tissue calcification differentiation, 3D rendering, and AI integration are being assessed for future use. In this article, we will discuss the established and developing applications of DECT in the setting of MSK radiology as well as the basic principles of DECT which facilitate them.

[Bone marrow edema syndromes of the knee]. / Knochenmarködem-Syndrome am Kniegelenk.

Bone marrow edema represents a common finding on magnetic resonance imaging (MRI) of the knee and other joints, which can occur as a primary pathology or as a secondary phenomenon of various bone and joint pathologies. This article reviews the terminology, definition, pathology and differential diagnosis of bone marrow edema of the knee taking into consideration current concepts.

Knockdown of the Shwachman-Diamond syndrome gene, SBDS, induces galectin-1 expression and impairs cell growth.

Shwachman-Diamond syndrome (SDS) is an autosomal recessive disorder characterized by exocrine pancreatic insufficiency and bone marrow failure. The depletion of SBDS protein by RNA interference has been shown to cause inhibition of cell proliferation in several cell lines. However, the precise mechanism by which the loss of SBDS leads to inhibition of cell growth remains unknown. To evaluate the impaired growth of SBDS-knockdown cells, we analyzed Epstein-Barr virus-transformed lymphoblast cells (LCLs) derived from two patients with SDS (c. 183_184TA > CT and c. 258 + 2 T > C). After 3 days of culture, the growth of LCL-SDS cell lines was considerably less than that of control donor cells. By annealing control primer-based GeneFishing PCR screening, we found that galectin-1 (Gal-1) mRNA expression was elevated in LCL-SDS cells. Western blot analysis showed that the level of Gal-1 protein expression was also increased in LCL-SDS cells as well as in SBDS-knockdown 32Dcl3 murine myeloid cells. We confirmed that recombinant Gal-1 inhibited the proliferation of both LCL-control and LCL-SDS cells and induced apoptosis (as determined by annexin V-positive staining). These results suggest that the overexpression of Gal-1 contributes to abnormal cell growth in SBDS-deficient cells.

HTLV-1 induces an inflammatory CD4+CD8+ T cell population in HTLV-1-associated myelopathy.

Human T cell leukemia virus type 1 (HTLV-1) is a retrovirus with preferential CD4+ T cell tropism that causes a range of conditions spanning from asymptomatic infection to adult T cell leukemia and HTLV-1-associated myelopathy (HAM), an inflammatory disease of the CNS. The mechanisms by which HTLV-1 induces HAM are poorly understood. By directly examining the ex vivo phenotype and function of T cells from asymptomatic carriers and patients with HAM, we show that patients with HAM have a higher frequency of CD4+CD8+ double-positive (DP) T cells, which are infected with HTLV-1 at higher rates than CD4+ T cells. Displaying both helper and cytotoxic phenotypes, these DP T cells are highly proinflammatory and contain high frequencies of HTLV-1-specific cells. Mechanistically, we demonstrate that DP T cells arise by direct HTLV-1 infection of CD4+ and CD8+ T cells. High levels of CD49d and CXCR3 expression suggest that DP T cells possess the ability to migrate to the CNS, and when cocultured with astrocytes, DP T cells induce proinflammatory astrocytes that express high levels of CXCL10, IFN-γ, and IL-6. These results demonstrate the potential of DP T cells to directly contribute to CNS pathology.

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.