Musculoskeletal glomus tumor: a review of 218 lesions in 176 patients.

OBJECTIVE: To review the spectrum of clinical and imaging features of glomus tumor involving the musculoskeletal system including the typically solitary forms as well as the rarer multifocal forms (glomuvenous malformation and glomangiomatosis). MATERIALS AND METHODS: A retrospective review of our institutional pathology database from 1996 to 2023 identified 176 patients with 218 confirmed glomus tumors. Primary imaging studies included MRI (125), radiographs (100), clinical/intraoperative photos (77), and ultrasound (36). Lesions were divided into two groups: those that are typically solitary involving specific anatomic areas (finger, toe, soft tissue, coccyx, and bone), and those that are multifocal (glomuvenous malformation and glomangiomatosis). RESULTS: The finger was the most frequently involved anatomic location for the classic (sporadic) glomus tumor occurring in 51% of patients, 77% of which were women, with the nail plate involved in more of the 75% of cases. Sporadic lesions involving the skin, subcutaneous adipose tissue, and deep soft tissue were termed "soft tissue," and were identified in 39% of patients, 90% of which were in the extremities and in men in 81% of cases. The multifocal syndromic forms of glomus disease occurred in younger individuals and involved less than 6% of the study group. Patients with glomuvenous malformation presented early with predominantly cutaneous involvement, while those with glomangiomatosis present later, often with both superficial and deep involvement, and a high rate of local tumor recurrence. CONCLUSION: While glomus tumor is generally uncommon, it frequently involves the musculoskeletal extremities. Knowledge of the spectrum of characteristic locations and appearances will facilitate definitive diagnosis.

Ankle, knee, and elbow arthrography: 2022 survey of Society of Skeletal Radiology members.

OBJECTIVE: To determine the preferred ankle, knee, and elbow arthrography injection techniques for Society of Skeletal Radiology (SSR) members and whether more recently described techniques are gaining acceptance. We also sought to determine whether the concept of knowledge translation might explain differences between the preferred technique, year of fellowship graduation, and year the newer technique was described. MATERIALS AND METHODS: A 29-question survey was created in Qualtrics and submitted to current SSR members to determine if they perform knee, elbow, and ankle arthrography, and if so, the year of fellowship completion and preferred approaches. Survey respondents indicated the starting and ending needle tip positions for three knee, two elbow, and three ankle arthrography approaches using grids placed over provided frontal and lateral radiographs. RESULTS: Two hundred seventy-four SSR members (mean post-fellowship 13 years; range 0-38) completed the survey and performed fluoroscopic-guided knee (93%), elbow (95%), and ankle (75%) arthrography. Preferred approaches included the following: knee lateral subpatellar (43%), anterior (40%); elbow radiocapitellar (74%); ankle anterior/peritendon (70%), lateral mortise (24%). Preference of newer technique was related to fellowship graduation year and publication year for the ankle mortise (26% before, 42% after; p = 0.03) and posterior trans-triceps elbow articles (19% before, 33% after; p < 0.01). The anterior knee approach preference increased from 11% in 2008 to 40% (p ≤ 0.001). CONCLUSION: Nearly twice as many SSR members who graduated after the posterior trans-triceps and ankle mortise techniques were published prefer them for performing arthrography, possibly due to knowledge translation. The preference of the anterior knee arthrography approach has increased nearly fourfold since 2008.

ACR Appropriateness Criteria® Imaging After Total Hip Arthroplasty.

This article reviews evidence for performing various imaging studies in patients with total hip prostheses. Routine follow-up is generally performed with radiography. Radiographs are also usually the initial imaging modality for patients with symptoms related to the prosthesis. Following acute injury with pain, noncontrast CT may add information to radiographic examination regarding the presence and location of a fracture, component stability, and bone stock. Image-guided joint aspiration, noncontrast MRI, and white blood cell scan and sulfur colloid scan of the hip, are usually appropriate studies for patients suspected of having periprosthetic infection. For evaluation of component loosening, wear, and/or osteolysis, noncontrast CT or MRI are usually appropriate studies. Noncontrast MRI is usually appropriate for identifying adverse reaction to metal debris related to metal-on-metal articulations. For assessing patients after hip arthroplasty, who have trochanteric pain and nondiagnostic radiographs, ultrasound, or MRI are usually appropriate studies. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision process support the systematic analysis of the medical literature from peer reviewed journals. Established methodology principles such as Grading of Recommendations Assessment, Development, and Evaluation or GRADE are adapted to evaluate the evidence. The RAND/UCLA Appropriateness Method User Manual provides the methodology to determine the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where peer reviewed literature is lacking or equivocal, experts may be the primary evidentiary source available to formulate a recommendation.

Bone Tumor Risk Stratification and Management System: A Consensus Guideline from the ACR Bone Reporting and Data System Committee.

The assessment and subsequent management of a potentially neoplastic bone lesion seen at diagnostic radiography is often complicated by diagnostic uncertainty and inconsistent management recommendations. Appropriate clinical management should be directed by risk of malignancy. Herein, the ACR-sponsored Bone Reporting and Data System (Bone-RADS) Committee, consisting of academic leaders in the fields of musculoskeletal oncology imaging and orthopedic oncology, presents the novel Bone-RADS scoring system to aid in risk assignment and provide risk-aligned management suggestions. When viewed in the proper clinical context, a newly identified bone lesion can be risk stratified as having very low, low, intermediate, or high risk of malignancy. Radiographic features predictive of risk are reviewed include margination, pattern of periosteal reaction, depth of endosteal erosion, pathological fracture, and extra-osseous soft tissue mass. Other radiographic features predictive of histopathology are also briefly discussed. To apply the Bone-RADS scoring system to a potentially neoplastic bone lesion, radiographic features predictive of risk are each given a point value. Point values are summed to yield a point total, which can be translated to a Bone-RADS score (1-4) with corresponding risk assignment (very low, low, intermediate, high). For each score, evidence-based and best practice consensus management suggestions are outlined. Examples of each Bone-RADS scores are presented, and a standardized diagnostic radiography report template is provided.

Angiolipoma: a review of 778 lesions in 344 patients.

BACKGROUND: Angiolipomas are benign subcutaneous nodules that are commonly multifocal and easily overlooked by those not familiar with their appearance. The objective of this study was to identify the spectrum of the clinical and imaging features of this lesion, to include MR, CT, and US features. METHODS: A retrospective review of our institutional pathology database for biopsy-proven cases of angiolipoma between January 1, 2019, through December 31, 2021, was done. We identified 334 patients who underwent surgical resection of 788 individual lesions. MR imaging studies were available in 43 cases, CT in 39 cases, and ultrasound imaging in 72 cases. Clinical features (patient age, gender, surgical indication, number of lesions) were reviewed. Imaging feature analysis included the anatomic location, content of fat, vascularity, and modality-specific imaging features. RESULTS: All 778 angiolipomas were located in the subcutaneous tissues (median size, 2.4 cm, range 0.4-7.7 cm), with over 51% located in the upper extremity. The most common presentation was a symptomatic mass or slowly growing symptomatic mass. Imaging showed a subcutaneous lesion with a lobulated bean shape, which typically abutted the skin. Intralesional fat was identified in 85% of lesions on CT and MRI. Vessels were commonly seen on CT and MR, with enhancement best seen on MR. On US, lesions were heterogeneous and mildly hyperechoic, most often with no identifiable vascularity. CONCLUSION: Angiolipomas typically have characteristic imaging features. Awareness of this diagnosis and the spectrum of its imaging features is important and can facilitate a definitive diagnosis.

Periosteal chondrosarcoma: an unusual juxtacortical sarcoma.

Periosteal chondrosarcoma is a rare tumor. It can be difficult to diagnose radiographically and pathologically and can be confused with periosteal osteosarcoma; however, the treatment of these two lesions is quite different. Increased awareness of imaging features of this lesion, particularly those that can help differentiate it from other surface-based tumors, can help one recognize this entity. We report the case of a periosteal chondrosarcoma in a young woman, highlighting the diagnostic imaging features of this disease, and her treatment with a joint-sparing geometric resection of the distal femur, using patient-specific 3D-printed cutting guides and matched allograft reconstruction.

ACR Appropriateness Criteria® Imaging After Shoulder Arthroplasty: 2021 Update.

Shoulder arthroplasty is a common orthopedic procedure with a complication rate reported to be as high as 39.8% and revision rates as high as 11%. Symptoms related to postoperative difficulties include activity-related pain, decreased range of motion, and apprehension. Some patients report immediate and persistent dissatisfaction, although others report a symptom-free postoperative period followed by increasing pain and decreasing shoulder function and mobility. Imaging plays an important role in diagnosing postoperative complications of shoulder arthroplasties. The imaging algorithm should always begin with radiographs. The selection of the next imaging modality depends on several factors, including findings on the initial imaging study, clinical suspicion of an osseous versus soft-tissue injury, and clinical suspicion of infection.The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Calcific Tendinosis Reduces Diagnostic Performance of Magnetic Resonance Imaging in the Detection of Rotator Cuff Tears.

OBJECTIVE: This study aimed to investigate the effect of calcific tendinosis on the diagnosis of rotator cuff tears (RCTs) on magnetic resonance imaging (MRI) and magnetic resonance arthrography (MRA). MATERIALS AND METHODS: Calcific tendinosis was confirmed radiographically. Two musculoskeletal radiologists then retrospectively and independently reviewed the MRI/MRA examinations, with surgery or arthroscopy performed within 90 days of the MRI. Rotator cuffs were categorized as no tear, partial-thickness tear, and full-thickness tear. Partial-thickness tear/full-thickness tear groups were combined for analysis. RESULTS: Forty-eight MRI (mean age, 63.4 years; range, 37-83 years; female-to-male ratio, 29:19) and 7 MRA (mean age, 49.2 years; range, 25-60 years; female-to-male ratio, 4:3) patients were included. Reader 1 and reader 2 sensitivity/specificity values for RCTs on MRI were 95%/50% and 89%/30%, and the values on MRA were 100%/67% and 100%/100%, respectively. Overall agreement was present in 87% (48 of 55; κ = 0.55 [95% confidence interval, 0.26-0.85]). CONCLUSIONS: Magnetic resonance imaging has decreased specificity in diagnosing RCTs when calcific tendinosis is present. Magnetic resonance arthrography performed better in this population and could be considered.

Comparative Accuracy of 1.5T MRI, 3T MRI, and Static Ultrasound in Diagnosis of Small Gaps in Repaired Flexor Tendons: A Cadaveric Study.

PURPOSE: We hypothesized that magnetic resonance imaging (MRI) would more accurately diagnose small gaps (<6 mm) after flexor tendon repair than static ultrasound (US) and that suture artifact would negatively impair accuracy. METHODS: A laceration of the flexor digitorum profundus was created in 160 fresh-frozen cadaveric digits and randomized to either an intact repair (0-mm gap) or repairs using a locked 4-strand suture repair with either 4-0 Prolene, Ethibond, or and gaps of 2, 4,or 6 mm; or no suture in which 2-, 4-, or 6-mm gaps were created without a suture crossing the repair site. We performed 1.5T and 3T MRI and static US studies; gap widths were estimated by radiologists blinded to suture presence and true gap widths. RESULTS: The 1.5 and 3.0T MRI had a lower mean error than US for gap sizes 0 and 2 mm. All 3 modalities performed similarly for 4- and 6-mm gaps. Documentation of imaging artifact worsened error, and odds of seeing artifacts were 1.72 higher with MRI than with US. Suture did not worsen artifact nor impair accuracy for any of the 3 modalities. When no suture was used, all 3 modalities significantly overestimated the true gap. CONCLUSIONS: MRI is most accurate for small gaps less than 4 mm. Although all modalities overestimated gap sizes in specimens with a 0-mm gap (intact tendon repair), mean overestimation (<2 mm) was not clinically relevant. Ultrasound overestimated 2-mm gaps (clinically intact repairs), whereas MRIs did not. We recommend MRI for evaluation of gaps after flexor tendon repair. The 1.5T has slightly better sensitivity and specificity for distinguishing clinically intact (gap < 3 mm) from clinically impaired (gap > 3 mm) repairs than the 3T. CLINICAL RELEVANCE: Accurate diagnosis of intact repairs or small gaps (<3 mm) might prevent unnecessary exploration or allow modification of rehabilitation protocols. Diagnosis of clinically relevant gaps (3-6 mm) may allow for earlier revision surgery before significant tendon retraction and adhesions develop, possibly necessitating a staged reconstruction.

ACR Appropriateness Criteria® Acute Trauma to the Ankle.

Acute injuries to the ankle are frequently encountered in the setting of the emergency room, sport, and general practice. This ACR Appropriateness Criteria defines best practices for imaging evaluation for several variants of patients presenting with acute ankle trauma. The variants include scenarios when Ottawa Rules can be evaluated, when there are exclusionary criteria, when Ottawa Rules cannot be evaluated, as well as specific injuries. Clinical scenarios are followed by the imaging choices and their appropriateness with an accompanying narrative explanation to help physicians to order the most appropriate imaging test. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

ACR Appropriateness Criteria® Chronic Foot Pain.

Chronic foot pain is a frequent clinical complaint, which can significantly impact the quality of live in some individuals. These guidelines define best practices with regards to requisition of imaging studies based on specific clinical scenarios, which have been grouped into different variants. Each variant is accompanied by a brief description of the usefulness, advantages, and limitations of different imaging modalities. The present narrative is the result of an exhaustive assessment of the available literature and a thorough review process by a panel of experts on Musculoskeletal Imaging. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Skeletal Radiology: the year in review 2019.

In 2019, Skeletal Radiology published a total of 253 articles including 111 scientific articles, 36 review articles, 51 case reports, 16 Test-Yourself cases, 15 technical reports, as well as multiple browser notes, meeting abstracts, and meeting summaries. As we have done previously, in this review, we will highlight those articles that stimulated the most interest from our readers, as measured by their downloads, and those that stimulated other researchers and authors, as measured by their citations. The manuscripts highlighted herein were chosen from this list.

Desmoplastic Fibroblastoma: An Uncommon Tumor With a Relatively Characteristic MRI Appearance.

OBJECTIVE. We undertook this study to determine the radiologic features of desmo-plastic fibroblastoma. MATERIALS AND METHODS. We reviewed available radiologic images for 29 pathologically confirmed desmoplastic fibroblastomas, including images from MRI, radiography, ultrasound (US), and CT. RESULTS. The patient population included 14 women and 15 men (mean age, 60 years; range, 23-96 years). Typically, lesions were oval or lobulated and relatively small (mean, 5.6 cm). In 14 of the 22 cases that included patient histories, lesions had grown slowly, with two eventually causing pain. The remaining eight were discovered incidentally. All lesions involved or were below the deep fascia. Lesions were well-defined and associated with muscle (45%), deep fascia (28%), joint (21%), or tendon (7%). MR images were available in 26 cases; 14 included unenhanced and contrast-enhanced studies. On MRI imaging all lesions were well-defined and adjacent to dense connective tissue. On T1-weighted images, lesions showed varying amounts of low and intermediate signal intensity similar to that of tendon and skeletal muscle, respectively. On fluid-sensitive images, lesions were more heterogeneous, generally showing a wider spectrum of decreased to intermediate signal intensity. On contrast-enhanced MR images, enhancement was characteristically peripheral and septal with patchy areas of homogeneity. In the 10 cases with radiographs, images showed negative findings or a nonmineralized mass. The 10 available ultrasound studies showed mixed echogenicity. In eight patients, unenhanced CT showed lesions having attenuation similar to that of skeletal muscle. CONCLUSION. Desmoplastic fibroblastoma is an uncommon neoplasm with a relatively characteristic MRI appearance.

ACR Appropriateness Criteria® Acute Trauma to the Knee.

Acute trauma to the knee is a common presentation seen in the emergency department. After a routine clinical examination, imaging is frequently performed to facilitate the diagnosis and almost always starts with radiographs. If clinically indicated, advanced cross-sectional imaging may then be performed for further evaluation. CT is often performed for preoperative planning of the complex tibial plateau and distal femur fractures. Currently, MRI is the study of choice for evaluation of bone marrow, internal derangements, and other soft-tissue injuries about the knee joint. In patients with knee dislocations, MR angiography may be performed simultaneously with MRI for evaluation of internal derangements and vascular injuries with less morbidity compared to conventional angiography. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

ACR Appropriateness Criteria® Acute Trauma to the Foot.

Acute injuries to the foot are frequently encountered in the emergency room and in general practice settings. This publication defines best practices for imaging evaluations for several variants of patients presenting with acute foot trauma. The variants include scenarios when the Ottawa rules can be evaluated, when there are exclusionary criteria, and when suspected pathology is in anatomic areas not addressed by the Ottawa rules. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

ACR Appropriateness Criteria® Primary Bone Tumors.

Although primary bone tumors are relatively uncommon, appropriate imaging evaluation is essential when they are suspected or incidentally detected. In almost all cases, radiographs are the most appropriate initial imaging study for screening and characterization of primary bone tumors. Radiographs often provide sufficient information for diagnosis and to guide the treating clinician. However, when conventional radiographs alone are inadequate, they still often guide the selection of the most appropriate next step for advanced imaging. MRI and CT are typically the most appropriate next step. MRI provides excellent soft-tissue contrast allowing for evaluation of the tissue composition (such as fat, hemorrhage, fluid levels) and anatomic extent of bone tumors. CT provides complementary information, with its ability to detect subtle matrix mineralization or periosteal reaction that may not be seen on radiographs or MRI. This publication focuses on six common variants to guide diagnosis and management of primary bone tumors. In addition to conventional radiographs, appropriate use of MRI, CT, PET/CT, bone scan, and ultrasound are discussed. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

ACR Appropriateness Criteria® Suspected Osteomyelitis of the Foot in Patients With Diabetes Mellitus.

Diabetes-related foot complications such as soft-tissue infection, osteomyelitis, and neuropathic osteoarthropathy account for up to 20% of all diabetic-related North American hospital admissions. Radiography of the foot is usually appropriate as the initial screening examination in diabetic patients with suspected osteomyelitis of the foot. For follow-up examination, MRI of the foot with or without contrast enhancement demonstrates excellent soft-tissue contrast and sensitivity to marrow abnormalities with high-resolution detail in multiple anatomic planes and is usually appropriate when osteomyelitis or early neuropathic arthropathy is suspected. This publication of diabetes-related foot complications summarizes the literature and makes recommendations for imaging based on the available data. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

ACR Appropriateness Criteria® Acute Hip Pain-Suspected Fracture.

Acute hip pain following a low-force trauma such as a ground-level fall is a common clinical problem. In the elderly osteoporotic population, this is frequently the result of fractures of the proximal femur or pelvis. As physical examination is often inconclusive, imaging is critical for diagnosis. Radiographs are the preferred first-line imaging modality, although their sensitivity is limited for nondisplaced fractures and further imaging may be necessary as discussed in this article and summarized in the recommendations. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.