Diagnostic efficacy of image-guided core needle biopsy of suspected malignant osseous lesions: a retrospective cohort study from a single academic institution.

OBJECTIVES: To evaluate diagnostic yield and accuracy of image-guided core needle biopsy (ICNB) of suspected malignant osseous lesions in a large cohort of adults, evaluate what factors influence these measures, and offer technical recommendations to optimize yield. METHODS: A retrospective analysis of 2321 ICNBs performed from 2010 to 2021 was completed. The diagnostic yield and accuracy of the biopsies as well as a series of patient, lesion-related, and technical factors were retrospectively analyzed. Multivariate statistical analysis was performed to evaluate what factors were associated with yield and accuracy. Different cutoff values of total core length and core number were then tested to determine threshold values in relation to increased diagnostic yield. RESULTS: Diagnostic yield was 98.2% (2279/2321) and accuracy was 97.6% (120/123). Increased total core length (odds ratio [OR] = 2.34, 95% confidence interval [CI] (1.41-3.90), p = 0.001), core number (OR = 1.51, 95% CI (1.06-2.16), p = 0.02) and presence of primary malignancy (OR = 2.81, 95% CI (1.40-5.62), p = 0.004) were associated with improved yield. Lesion location in an extremity (OR = 0.27, 95% CI (0.11-0.68), p = 0.006) and using fluoroscopic imaging guidance (OR = 0.33, 95% CI (0.12-0.90), p = 0.03) were associated with lower yield. Cutoff thresholds in relation to increased diagnostic yield were found to be 20 mm total core length (marginal OR = 4.16, 95% CI = (2.09-9.03), p < 0.001), and three total cores obtained (marginal OR = 2.78, 95% CI (1.34-6.54), p = 0.005). None of the analyzed factors influenced diagnostic accuracy. CONCLUSIONS: ICNB has a high rate of diagnostic yield and accuracy. Several factors influence diagnostic yield; 20 mm core length and three total cores optimize yield. CLINICAL RELEVANCE STATEMENT: Image-guided core needle biopsy of suspected malignant osseous lesions is a safe procedure with a very high rate of diagnostic yield and accuracy. Obtaining 20 mm total core length and three total cores optimizes diagnostic yield. KEY POINTS: • In a retrospective cohort study, image-guided core needle biopsy of suspected osseous malignant lesions in adults was found to have very high rates of diagnostic yield and accuracy. • Increased total core length and core number of biopsies were each associated with increased diagnostic yield, and these relationships reached thresholds at 20 mm total core length and three total cores obtained. • The presence of a known primary malignancy was also associated with increased yield while using fluoroscopic imaging guidance and lesion location in an extremity were associated with decreased yield.

Xanthogranulomatous epithelial tumors and keratin-positive giant cell-rich soft tissue tumors: two aspects of a single entity with frequent HMGA2-NCOR2 fusions.

Xanthogranulomatous epithelial tumor (XGET) and keratin-positive giant cell-rich soft tissue tumor with HMGA2-NCOR2 fusion (KPGCT) are two recently described neoplasms with both distinct and overlapping clinical and histopathologic features. We hypothesized that XGET and KPGCT may be related and represent a histologic spectrum of a single entity. To test this, we sought to characterize the clinical, radiographic, immunohistochemical, ultrastructural and molecular features of additional tumors with features of XGET and/or KPGCT, which we refer to descriptively as keratin-positive xanthogranulomatous/giant cell-rich tumors (KPXG/GCT). The archives were searched for potential cases of KPXG/GCT. Clinical and imaging features were noted. Slides were assessed for histologic and immunohistochemical findings. Ultrastructural and next generation RNA sequencing-based analysis were also performed. Nine cases were identified arising in seven women and two men [median age of 33 years (range: 12-87)]. Median tumor size was 4 cm (range: 2.4-14.0 cm) and tumors presented in the thigh (2), buttock (1), forearm (2), groin (1), cranial fossa (1), ilium (1), and tibia (1). Morphologically, tumors were most frequently characterized by a fibrous capsule, with associated lymphoid reaction, enclosing a polymorphous proliferation of histiocytes, giant cells (Touton and osteoclast-types), mixed inflammatory infiltrate, hemorrhage and hemosiderin deposition, which imparted a variably xanthogranulomatous to giant cell tumor-like appearance. One case clearly showed mononuclear cells with eosinophilic cytoplasm characteristic of XGET. All cases expressed keratin and 7 of 9 were found to harbor HMGA2-NCOR2 fusions including cases with xanthogranulomatous appearance. One patient developed local recurrence and multifocal pulmonary lesions, which were radiographically suspicious for metastases. Shared clinical, histologic and immunohistochemical features, and the shared presence of HMGA2-NCOR2 fusions supports interpretation of KPXG/GCT as a single entity which includes XGET and KPGCT. Given limited clinical follow-up to date and rare cases with apparently aggressive findings, we provisionally regard these tumors as having uncertain biologic potential.

The pivot fracture: an unusual tibial plateau fracture found in association with acute ACL injury.

Tibial plateau fractures are common fractures which are often associated with concurrent soft tissue injury and for which accurate preoperative diagnosis is important for development of an appropriate treatment plan and outcome prediction. Here, we present an extreme manifestation of the pivot shift phenomenon with an unusual tibial plateau fracture with flipped component not described by any existing tibial plateau fracture classification system and never reported previously in conjunction with an anterior cruciate ligament injury. We describe the utilization of advanced imaging not typically utilized in the management of tibial plateau fractures in combination with clinical suspicion to diagnose the associated soft tissue injuries and develop an appropriate management plan.

Three-Column Classification System for Tibial Plateau Fractures: What the Orthopedic Surgeon Wants to Know.

Recent orthopedic surgical literature emphasizes a three-column approach to understand and guide the treatment of tibial plateau fractures. This three-column classification system published in 2010 relies on preoperative CT images to depict injuries to the medial, lateral, and posterior columns of the tibial plateau and improves surgical outcomes in complex tibial plateau fractures with coronal fracture planes and posterior plateau fracture fragments requiring dorsal plating. Tibial plateau fracture classification systems traditionally used by radiologists and orthopedic surgeons, including the Schatzker and the Arbeitsgemeinschaft für Osteosynthesefragen-Orthopedic Trauma Association (AO-OTA) classification systems, rely on findings at anteroposterior radiography and lack the terminology to accurately characterize fractures in the coronal plane involving the posterior tibial plateau. Incorporating elements from the contemporary three-column classification system into radiology reports will enhance radiologists' descriptions of these injuries. It is essential for radiologists to understand the role of clinical assessment and the pertinent imaging findings taken into consideration by orthopedic surgeons in their management of these injuries. This understanding includes familiarity with injury patterns and how they relate to mechanism of injury, patient demographics, and underlying pertinent comorbidities. Evaluating findings on initial radiographs is the basis of tibial plateau fracture diagnosis. Additional information provided by preoperative cross-sectional imaging, including two-dimensional and three-dimensional CT and MRI in specific circumstances, aids in the identification of specific soft-tissue injuries and fracture morphologies that influence surgical management. These specific fracture morphologies and soft-tissue injuries should be identified and communicated to orthopedic surgeons for optimal patient management. Online DICOM image stacks are available for this article. ©RSNA, 2020.

Ulnar shaft stress fractures in fast-pitch softball pitchers: a case series and proposed mechanism of injury.

BACKGROUND: Stress fractures of the upper extremities in athletes are important injuries for radiologists to appreciate despite being far less common than stress fractures of the lower extremities. Among upper extremity stress fractures, those involving the olecranon have been well described in overhead pitching athletes. Isolated stress fractures of the ulnar shaft however are less commonly reported in the literature and considered to be rare. We have observed a correlation between young patients with ulnar shaft stress fractures and the activity of fast-pitch softball pitching. CASE REPORTS: In this series, we present the imaging findings in four cases of ulnar shaft stress fractures in softball pitchers who presented with insidious onset forearm pain. Furthermore, a review of the literature focusing on softball pitching mechanics is provided to offer a potential underlying mechanism for the occurrence and location of these injuries. CONCLUSION: An awareness of the imaging appearance of ulnar shaft stress fractures along with an understanding of its proposed mechanism will facilitate accurate and timely imaging diagnosis of this injury by the radiologist.

The diagnostic performance of MRI signs to distinguish Pectoralis major tendon avulsions from Myotendinous injuries.

BACKGROUND: Management of pectoralis major (PM) injuries is largely determined by the anatomic location of the injury, with tendon avulsions from the humerus requiring surgery while myotendinous (MT) injuries are typically managed non-operatively. Because physical examination cannot reliably make this distinction, MRI is often used for staging. However, correct classification can also be difficult with MRI where there is extensive soft tissue edema and distorted anatomy. OBJECTIVE: To determine the diagnostic performance of primary and secondary MRI signs of PM injury for distinguishing tendon avulsions from MT injuries in a selected sample of patients that underwent surgical repair using a practical interpretation algorithm. METHODS: In this retrospective study, 3 blinded observers independently assessed the MRI findings of 17 patients with PM injury (including 12 acute injuries, 4 chronic, and 1 of uncertain age) where subsequent surgery documented tendon avulsion (11) and MT injuries (6) by applying the primary MRI criteria of absent tendon at the humerus, retracted tendon stump, epicenter of edema, and the secondary finding of soft tissue edema contacting the anterior humeral cortex. Operative findings were used as the reference standard. Sensitivity, specificity, and positive and negative predictive value were recorded for each finding. RESULTS: The primary MRI finding of lack of a visible tendon at the insertion (sensitivity 82-100%, specificity 100%) and the secondary finding of edema contacting the anterior humeral cortex (sensitivity 64-91%, specificity 67-100%) were both useful for the distinction of tendon avulsion from MT injury, particularly in acute injuries. The presence of a retracted tendon stump and the epicenter of edema were not reliable findings. The use of a decision tree including the secondary finding of humeral edema increased the sensitivity and specificity for 2 of the 3 observers. CONCLUSION: MRI assessment of PM injury focused on the humeral insertion of the PM tendon allows accurate distinction of tendon avulsion from MT injury. CLINICAL IMPACT: This study describes a practical approach to classifying PM injuries with MRI to distinguish injuries that require surgery from those that can potentially be managed conservatively.

Primary osseous sacral neuroblastoma in an adult.

Neoplasms of the sacrum are rare. Given the non-specific imaging findings in sacral lesions, the imaging-based differential diagnosis is always difficult. This case is about an adult with primary sacral neuroblastoma and we have discussed imaging and histopathological findings of this rare tumor.

Imaging the Postoperative Knee Meniscus: An Evidence-Based Review.

OBJECTIVE: Unenhanced MRI, indirect MR arthrography, direct MR arthrography, and CT arthrography are each currently used to evaluate patients with recurrent knee pain after meniscus surgery. The purpose of this study is to review the evidence for the use of these examinations in patients with suspected recurrent meniscus tear. CONCLUSION: Direct and indirect MR arthrography are superior to conventional MRI for the assessment of the postoperative meniscus after meniscus repair or partial meniscectomy involving more than 25% of the meniscus.

Biopsy of CT-Occult Bone Lesions Using Anatomic Landmarks for CT Guidance.

OBJECTIVE: The purpose of this study is to evaluate the histopathologic diagnostic yield, sample size, procedural time, and dose-length product (DLP) for the biopsy of CT-occult lesions found at MRI or PET or both. MATERIALS AND METHODS: A retrospective review of our radiology information system for biopsies of CT-occult lesions using CT guidance from January 1, 2010, through December 31, 2014, was performed and compared with a selection of CT-guided biopsies of CT-evident bone lesions during the same period. The data were then evaluated for diagnostic yield of histopathologic diagnosis, procedural time, use of sedation medication, DLP, and size of specimens obtained. RESULTS: A total of 30 CT-occult biopsies met the inclusion criteria. Twenty-seven of those biopsies had results that were concordant with the patient's primary histopathologic diagnosis, imaging findings, and clinical course. In the CT-evident lesion group, concordant histopathologic abnormalities were identified in 27 of 30 patients. There was a statistically significant increase in number of samples obtained for the CT-evident lesions compared with CT-occult lesions. There was no statistically significant difference in total specimen length, DLP, number of CT scans, procedural time, or use of sedation medication between the CT-occult and CT-evident biopsy groups. CONCLUSION: Biopsy of CT-occult lesions using anatomic landmarks achieves diagnostic yields similar to those for CT-guided biopsy of CT-evident lesions.

Primary Rosai-Dorfman disease of the femur.

We report a 19-year-old man with the rare occurrence of primary osseous Rosai-Dorfman disease (RDD). The patient presented with a painful, solitary, bone marrow-replacing lesion in the distal femur. A diagnosis of chronic osteomyelitis was initially made on tissue from a CT-guided needle biopsy of the lesion; however, the diagnosis of RDD was eventually made after histological and immunohistochemical analysis of material from a subsequent curettage. No lymphadenopathy or other sites of involvement were found on clinical evaluation and PET-CT. To our knowledge, this is the first report of solitary osseous RDD based on systemic staging with PET-CT. We review the clinical, imaging, and histological features of primary osseous RDD, including pitfalls in diagnosis.

Manubrial stress fractures diagnosed on MRI: report of two cases and review of the literature.

In contrast to widely-reported sternal insufficiency fractures, stress fractures of the sternum from overuse are extremely rare. Of the 5 cases of sternal stress fracture published in the English-language medical literature, 3 were in the sternal body and only 2 were in the manubrium. We describe two cases of manubrial stress fracture related to golf and weightlifting, and present the first report of the MR findings of this injury. In each of these cases, the onset of pain was atraumatic, insidious, and associated with increased frequency of athletic activity. Imaging was obtained because of clinical diagnostic uncertainty. On MRI, each patient had a sagittally oriented stress fracture of the lateral manubrium adjacent to the first rib synchondrosis. Both patients had resolution of pain after a period of rest, with subsequent successful return to their respective activities. One patient had a follow-up MRI, which showed resolution of the manubrial marrow edema and fracture line. Based on the sternal anatomy and MR findings, we hypothesize that this rare injury might be caused by repetitive torque of the muscle forces on the first costal cartilage and manubrium, and propose that MRI might be an effective means of diagnosing manubrial stress fracture.

Athletic injuries of the lateral abdominal wall: review of anatomy and MR imaging appearance.

The lateral abdominal wall is comprised of three muscles, each with a different function and orientation. The transversus abdominus, internal oblique, and external oblique muscles span the abdominal cavity between the iliocostalis lumborum and quadratus lumborum posteriorly and the rectus abdominis anteriorly. The lateral abdominal wall is bound superiorly by the lower ribs and costal cartilages and inferiorly by the iliac crest and inguinal ligament. The lateral abdominal wall may be acutely or chronically injured in a variety of athletic endeavors, with occasional acute injuries in the setting of high-energy trauma such as motor vehicle collisions. Injuries to the lateral abdominal wall may result in lumbar hernia formation, unique for its high incarceration rate, and also Spigelian hernias. This article will review the anatomy, the magnetic resonance (MR) imaging approach, and the features and complications of lateral abdominal wall injuries.

Review of supplemental views and stress radiography in musculoskeletal trauma: upper extremity.

The standard radiographic series is not always sufficient to diagnose and characterize subtle musculoskeletal injuries. Missed or delayed diagnoses can negatively affect patient acute morbidity and long-term outcomes. Similarly, management based on erroneous diagnoses may lead to unnecessary treatment and restrictions. Body part or joint specific supplemental radiographic views and stress radiography offer an alternative for further evaluation of subtle injuries in specific clinical situations and may obviate the need for the added cost and potential ionizing radiation exposure of further cross-sectional imaging. Familiarity with these complementary exams allows radiologists to play an important role in patient care, as their utilization can improve diagnostic accuracy, clarify subtle or uncertain findings, and direct timely patient management. This review highlights important supplemental views and stress radiographic examinations useful in the evaluation of emergent upper extremity musculoskeletal trauma.

Review of supplemental views and stress radiography in musculoskeletal trauma: lower extremity.

The standard radiographic series is not always sufficient to diagnose and characterize subtle musculoskeletal injuries. Missed or delayed diagnoses can negatively affect patient acute morbidity and long-term outcomes. Similarly, management based on erroneous diagnoses may lead to unnecessary treatment and restrictions. Body-part- or joint-specific supplemental radiographic views and stress radiography offer an alternative for further evaluation of subtle injuries in specific clinical situations and may obviate the need for the added cost and potential ionizing radiation exposure of further cross-sectional imaging. Familiarity with these complementary exams allows radiologists to play an important role in patient care, as their utilization can improve diagnostic accuracy, clarify subtle or uncertain findings, and direct timely patient management. This review highlights important supplemental views and stress radiographic examinations useful in the evaluation of emergent lower extremity musculoskeletal trauma.

Diagnostic efficacy and clinical impact of image-guided core needle biopsy of suspected vertebral osteomyelitis.

OBJECTIVES: The diagnostic yield and clinical impact of image-guided core needle biopsy (ICNB) of suspected vertebral osteomyelitis in adults is heterogenous in published studies owing to small sample sizes, indicating the need for large cohort studies. METHODS: A retrospective analysis of ICNBs was performed from 2010 to 2021 for patients with imaging findings consistent with vertebral osteomyelitis. For each biopsy, a series of factors were analyzed, as well as if histopathology was diagnostic of osteomyelitis and if microbiological cultures were positive. In addition, it was recorded in what way biopsy influenced clinical management regarding antimicrobial treatment. A multivariate statistical analysis was performed to evaluate the factors associated with yield. RESULTS: A total of 570 biopsies performed on 527 patients were included. A histopathologic diagnosis of osteomyelitis was made in 68.4% (359 of 525) of biopsies, and microbiological cultures were positive in 29.6% (169 of 570). Elevated erythrocyte sedimentation rate was positively associated with a histopathologic diagnosis of osteomyelitis (odds ratio [OR] =1.96, P = 0.007) and positive cultures from bone cores (OR = 1.02, P ≤0.001) and aspirate (OR = 1.02, P ≤0.001). Increased total core length was positively associated with a histopathologic diagnosis of osteomyelitis (OR = 1.81, P = 0.013) and positive cultures from bone cores (OR = 1.65, P = 0.049). Clinical management was affected by ICNB in 37.5% (214 of 570) of cases. CONCLUSIONS: In this large cohort, ICNB yielded approximately 30% positive cultures and changed clinical management in over one-third of the patients.

Image-guided biopsy and treatment of musculoskeletal tumors.

This article reviews the basics of image-guided intervention of musculoskeletal neoplasms. Image-guided procedures are playing an ever-increasing role in the diagnosis, staging, and treatment of musculoskeletal tumors. The successful handling of these lesions necessitates a multidisciplinary approach, with the radiologist working closely with the orthopedic oncologic surgeon, medical oncologist, radiation oncologist, and pathologist to ensure that the procedure is performed in a way that maximizes the chance of definitive diagnosis and/or the treatment effect while minimizing potential complications. To accomplish these goals, the radiologist must be familiar with the indications and contraindications for any biopsy or treatment, effective procedure planning (e.g., selection of biopsy path, type of imaging guidance and biopsy needle, etc.), proper specimen handling, and potential treatment options such as thermal ablation or cement augmentation. Continued involvement after the procedure-including follow-up to ensure that pathology is concordant with imaging-is also crucial.

LRP6 High Bone Mass Characterized in Two Generations Harboring a Unique Mutation of Low-Density Lipoprotein Receptor-Related Protein 6.

Osteoblast Wnt/ß-catenin signaling conditions skeletal development and health. Bone formation is stimulated when on the osteoblast surface a Wnt binds to low-density lipoprotein receptor-related protein 5 (LRP5) or 6 (LRP6), in turn coupled to a frizzled receptor. Sclerostin and dickkopf1 inhibit osteogenesis if either links selectively to the first ß-propeller of LRP5 or LRP6, thereby disassociating these cognate co-receptors from the frizzled receptor. Sixteen heterozygous mutations identified since 2002 within LRP5 and three heterozygous mutations identified since 2019 within LRP6 prevent this binding of sclerostin or dickkopf1 and account for the exceptionally rare, but highly instructive, autosomal dominant disorders called LRP5 and LRP6 high bone mass (HBM). Herein, we characterize LRP6 HBM in the first large affected family. Their novel heterozygous LRP6 missense mutation (c.719C>T, p.Thr240Ile) was present in two middle-aged sisters and three of their sons. They considered themselves healthy. Their broad jaw and torus palatinus developed during childhood and, contrary to the two previous reports of LRP6 HBM, the appearance of their adult dentition was unremarkable. Skeletal modeling, defined radiographically, supported classification as an endosteal hyperostosis. Areal bone mineral density (g/cm2) of the lumbar spine and total hip featured accelerated increases reaching Z-scores of ~ +8 and +6, respectively, although biochemical markers of bone formation were normal. © 2023 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.

ACR Appropriateness Criteria® Soft Tissue Masses: 2022 Update.

Imaging should be performed in patients with a suspected soft tissue mass that cannot be clinically confirmed as benign. Imaging provides essential information necessary for diagnosis, local staging, and biopsy planning. Although the modalities available for imaging of musculoskeletal masses have undergone progressive technological advancements in recent years, their overall purpose in the setting of a soft tissue mass remains unchanged. This document identifies the most common clinical scenarios related to soft tissue masses and the most appropriate imaging for their assessment on the basis of the current literature. It also provides general guidance for those scenarios that are not specifically addressed. 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.

ACR Appropriateness Criteria® Management of Vertebral Compression Fractures: 2022 Update.

Vertebral compression fractures (VCFs) can have a variety of etiologies, including trauma, osteoporosis, or neoplastic infiltration. Osteoporosis related fractures are the most common cause of VCFs and have a high prevalence among all postmenopausal women with increasing incidence in similarly aged men. Trauma is the most common etiology in those >50 years of age. However, many cancers, such as breast, prostate, thyroid, and lung, have a propensity to metastasize to bone, which can lead to malignant VCFs. Indeed, the spine is third most common site of metastases after lung and liver. In addition, primary tumors of bone and lymphoproliferative diseases such as lymphoma and multiple myeloma can be the cause of malignant VCFs. Although patient clinical history could help raising suspicion for a particular disorder, the characterization of VCFs is usually referred to diagnostic imaging. The ACR 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 in which evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.