Skeletal Radiology最新文献

Lateral discoid meniscus is the most common meniscal congenital variant. A lateral discoid meniscus manifests with a spectrum of findings, including abnormalities in size and shape, disorganized collagen architecture, and/or hypermobility, predisposing the meniscus to early degeneration and tearing. The purpose of this narrative review is to discuss the anatomy of the lateral discoid meniscus and to highlight MRI findings that should be included in radiology reports to guide management.

Objective: To evaluate whether femoral neck-parallel reconstruction of CT images improves the correlation with dual-energy X-ray absorptiometry for osteoporosis assessment compared with conventional table-parallel reconstruction.

Materials and methods: A retrospective analysis was conducted on 174 patients who underwent hip CT and dual-energy X-ray absorptiometry. Two CT image reconstruction methods were compared: femoral neck-parallel and table-parallel methods. CT values were extracted from cancellous bone regions in the femoral neck corresponding to the area measured by DXA. Correlation coefficients between CT values and dual-energy X-ray absorptiometry-derived bone mineral density and T-scores were calculated. A stratified analysis by femoral neck-to-table angle (< 5° vs. ≥ 5°) was performed. Receiver operating characteristic (ROC) curve analysis was performed to compare the ability of each method to discriminate between patients with and without low bone mass (defined as osteoporosis or osteopenia).

Results: CT values from the femoral neck-parallel method showed significantly stronger correlations with bone mineral density (r = 0.74) and T-score (r = 0.77) than those from the table-parallel method (bone mineral density: r = 0.66, T-score: r = 0.71) (p = 0.001 for both). In patients with ≥ 5° misalignment, the femoral neck-parallel method showed significantly higher correlation coefficients than the table-parallel method (bone mineral density, p < 0.001; T-score, p = 0.005). ROC curve analysis revealed that the area under the curve for detecting low bone mass was higher in the femoral neck-parallel method (0.87) than in the table-parallel method (0.83) (p = 0.012).

Conclusions: Femoral neck-parallel reconstruction significantly improves the correlation between CT values and dual-energy X-ray absorptiometry for low bone mass assessment compared to table-parallel reconstruction.

Objective: To investigate the relationship between cartilage cap thickness, osteochondroma subtype (pedunculated vs. sessile), patient age, and multiple hereditary exostoses (MHE) diagnosis with malignant transformation of osteochondromas.

Methods: A single-institution retrospective study of patients who underwent surgical excision of one or more osteochondromas between 1983 and 2025 was conducted. The relationship between cartilage cap thickness, osteochondroma subtype (pedunculated vs. sessile), patient age, and MHE diagnosis with malignant transformation was investigated.

Results: Among 1138 pathology-confirmed osteochondromas, 1097 (96.4%) were benign osteochondromas and 41 (3.60%) underwent malignant transformation. In tumors with a pathology-measured cartilage cap (n = 411), benign tumors (n = 397) had a smaller median cap size than malignant lesions (0.3 cm [IQR: 0.2-0.6 cm] vs. 3.15 cm [IQR: 1.93-4.78 cm]; p < .0001). Among 27 malignant cases with preoperative imaging, 63% were sessile and 37% pedunculated. Patients with benign tumors were younger than those with malignant transformations (27.1 ± 15.9 vs. 37.8 ± 12.2 years; p < .0001). Patients with MHE had a greater incidence of malignant transformation compared to patients without (17% vs. 1.98%) (p < .0001). 137 MRIs and 37 CTs were compared to pathology measurements, yielding a concordance correlation coefficient of 0.80 and 0.92, respectively. The sensitivities and specificities were 29% and 91% for MRI and 67% and 94% for CT, respectively.

Conclusion: A thicker cartilage cap, older age, and confirmed MHE diagnosis were each significantly associated with a higher rate of malignant transformation. Multidisciplinary teams should factor in a patient's clinical presentation and past medical history in addition to the tumor characteristics in deciding the proper course of treatment.

Objectives: To evaluate the clinical impact of an artificial intelligence device, Rho, that opportunistically screens X-rays for low bone mineral density (BMD; DXA T-score < -1).

Materials and methods: Over 13 months, Rho analyzed X-rays from patients ≥ 50 years at a large independent health facility. Radiologists could opt to include Rho-flagged findings in their X-ray reports. DXAs that occurred within 6 months of an X-ray (from patients in the first 7 months of data collection) were categorized as being prompted by Rho ("Rho-generated") or arranged via usual standard-of-care practice ("pre-planned"), and their outcomes (diagnoses and 10-year fracture risk scores) were compared.

Results: Of 34,162 X-rays, Rho flagged 19,004 (56%) for low BMD, and radiologists included this information in 7726 (41%) reports. From the first 7 months of radiologists reporting Rho findings, initial and surveillance DXAs increased by factors of 1.8 and 1.4, respectively. Of 299 Rho-generated DXAs, 193 had low bone mass (- 2.5 < T-score < - 1) and 65 had osteoporosis. Rho-generated DXAs vs. pre-planned DXAs identified a greater proportion of patients with low BMD (87% vs. 69%; p < 0.001) and similar proportions of patients with elevated fracture risk (34% vs. 40%). The diagnostic yield was particularly marked in patients undergoing their first-ever DXA (84% vs. 60%; p < 0.001), and in males ≥ 65 years (83% vs. 45%; p < 0.001).

Conclusion: Incorporating Rho in radiology workflow nearly doubled initial bone health assessments and prompted additional surveillance DXA evaluations. Rho-generated DXAs captured higher rates of true low BMD than standard-of-care practices, particularly in older men.

The subchondral bone is an integral structural component of the knee with key roles in shock absorption and load distribution. Injuries to the subchondral bone, which may occur secondary to various etiologies including trauma, degenerative disease, or repetitive overuse, are commonly encountered in clinical practice. Radiographs are generally performed as an initial imaging test to identify any gross osseous abnormalities. However, magnetic resonance imaging (MRI) is the modality of choice for the accurate evaluation and characterization of subchondral bone abnormalities, such as osseous contusion, insufficiency fracture, stress response, osteonecrosis, arthropathy, and neoplasm. Similarly, osteochondral derangements, including osteochondral fracture and osteochondritis dissecans, are also accurately identified with MRI. Therefore, knowledge of the MRI appearance of both normal anatomy and derangements of the subchondral bone are necessary for accurate diagnosis. This article aims to provide a review of the imaging features of subchondral bone abnormalities in the knee, highlighting key diagnostic findings and recommended practices in radiologic terminology and reporting.

Krabbe disease is an autosomal recessive leukodystrophy where a deficiency of the galactosylceramide beta-hydrolase enzyme leads to accumulation of toxic substances which cause demyelination in both central and peripheral nervous systems. It is classified into early infantile, late infantile, juvenile and adult types based on the age of presentation. MRI of the brain in patients with Krabbe disease shows bilaterally symmetrical T2 hyperintense signal in the periventricular and deep white matter and in the corticospinal tracts. Patients can have peripheral neuropathy, which, on imaging, is commonly seen in the form of thickening and enhancement of cranial nerves and nerve roots of cauda equina. Our patient, a child aged eleven years, had intracranial lesions along with brachial plexopathy. This is the first described case of juvenile-onset Krabbe disease with brachial plexus involvement.

Objectives: To evaluate the impact of calcium suppression (CaSupp) imaging of spectral computed tomography (SpCT) on fracture detection in clinical routine in the acute trauma setting of the hand and wrist.

Materials and methods: Retrospective inclusion of 125 patients who underwent both X-ray and SpCT examinations of the hand and wrist in an acute trauma setting. Two independent readers evaluated fracture presence on X-ray, conventional CT, and conventional CT plus CaSupp images (time interval 4 weeks, each). Bone bruise (BBr) presence was evaluated on CaSupp images. Sensitivity and specificity were calculated according to the consensus reading as the reference standard.

Results: Of the 125 patients (mean age, 55 years ± 19.5 [SD]; 67 female), 120 presented with at least one fracture, for a total of 212 fractured bones. Sensitivity was increased significantly for both readers in CT + CaSupp (94.3 and 97.2%) compared to conventional CT (88.2 and 90.1%, p < .01) and X-ray (72.6 and 75.9%, p < .01). Specificity was 99.9 and 100% for CT + CaSupp, 99.8 and 99.9% for conventional CT, and 99.4 and 99.9% for X-ray. Reader 1 detected 13 additional fractures in CT + CaSupp compared to conventional CT alone, while Reader 2 detected 15 additional fractures. BBr was seen in 58% of all fractures, in 76% of multifragmentary fractures, and in 13% of avulsion fractures. Inter-reader κ was almost perfect for X-ray (κ = .85), CT and CT + CaSupp (κ = .95), and substantial for BBr (κ = .61).

Conclusion: CaSupp images in combination with conventional CT images significantly improved sensitivity for acute trauma fracture detection in the hand and wrist compared to conventional CT images alone and X-ray.

Objective: To synthesize magnetic resonance imaging (MRI) features and their reported diagnostic performance that differentiate benign from malignant soft-tissue tumors in alignment with the 2020 World Health Organization classification.

Materials and methods: A systematic review was conducted in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. PubMed, Embase, Scopus, and the Cochrane Central Register of Controlled Trials were searched through July 2024. Eligible studies reported MRI feature frequencies or diagnostic accuracy for common soft-tissue tumor subtypes. Reviews, case reports, duplicates, non-English publications, and studies outside the scope were excluded. Quality was assessed using the Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2).

Results: Seventy-six studies met inclusion criteria. In lipomatous tumors, homogeneous fat signal and thin septa supported lipoma, whereas thick or nodular septa and enhancement favored atypical or well-differentiated liposarcoma. Myxofibrosarcoma often demonstrated an infiltrative fascial "tail." Vascular lesions included angioleiomyoma with a reticular T2 pattern and glomus tumor with marked T2 hyperintensity and avid enhancement. In peripheral nerve sheath tumors, lower apparent diffusion coefficient values and peritumoral edema favored malignancy. Heterogeneity in imaging protocols precluded meta-analysis; results were summarized descriptively by subtype.

Conclusion: Consolidated MRI patterns-such as septal morphology in lipomatous tumors, the fascial tail in myxofibrosarcoma, characteristic T2 patterns in vascular lesions, and diffusion and edema cues in nerve sheath tumors-support differentiation of benign and malignant entities, enhance reader confidence, and inform biopsy and management. Standardized prospective studies are needed to validate these thresholds and improve generalizability.

Objectives: To characterize ankle magnetic resonance imaging (MRI) features in pediatric and young adult patients with familial Mediterranean fever (FMF) and compare them with those in juvenile idiopathic arthritis (JIA) and chronic nonbacterial osteomyelitis (CNO) in order to identify distinguishing or overlapping imaging features among the three conditions.

Methods: Twelve ankle MRI examinations from 11 patients with FMF (mean age 12.4 years, 7 females) were retrospectively evaluated and compared with 22 examinations from 17 patients diagnosed with JIA (12 patients/14 ankles, mean age 14.3 years, 8 females) or CNO (5 patients/8 ankles, mean age 10.2 years, 3 females). Calcaneal enthesitis features were assessed at the insertion site of the Achilles tendon, plantar fascia, and the long plantar tendon. Also evaluated were the presence of diffuse calcaneal bone marrow edema (BME), midfoot arthritis, synovitis, and tenosynovitis.

Results: Insertional calcaneal BME, an enthesitis-related feature, was more prevalent in FMF patients compared to both JIA and CNO, while among the three evaluated entheses, long plantar tendon enthesitis was significantly more prevalent in FMF patients only compared to those with JIA (p < 0.001). CNO presented a predominantly osseous inflammation pattern with diffuse calcaneal BME (87.5%, p < 0.001) and additional hindfoot BME (75%, p < 0.002), clearly distinct from FMF. Synovitis and tenosynovitis were more commonly observed in JIA patients, although the differences compared to FMF and CNO were not statistically significant.

Conclusion: Although imaging features overlap among FMF, CNO, and JIA, distinct MRI patterns emerge: enthesitis predominates in FMF, osteitis in CNO, and synovitis in JIA.