Interdisciplinary consensus statements on imaging of DRUJ instability and TFCC injuries.

OBJECTIVES: The purpose of this agreement was to establish evidence-based consensus statements on imaging of distal radioulnar joint (DRUJ) instability and triangular fibrocartilage complex (TFCC) injuries by an expert group using the Delphi technique. METHODS: Nineteen hand surgeons developed a preliminary list of questions on DRUJ instability and TFCC injuries. Radiologists created statements based on the literature and the authors' clinical experience. Questions and statements were revised during three iterative Delphi rounds. Delphi panelists consisted of twenty-seven musculoskeletal radiologists. The panelists scored their degree of agreement to each statement on an 11-item numeric scale. Scores of "0," "5," and "10" reflected complete disagreement, indeterminate agreement, and complete agreement, respectively. Group consensus was defined as a score of "8" or higher for 80% or more of the panelists. RESULTS: Three of fourteen statements achieved group consensus in the first Delphi round and ten statements achieved group consensus in the second Delphi round. The third and final Delphi round was limited to the one question that did not achieve group consensus in the previous rounds. CONCLUSIONS: Delphi-based agreements suggest that CT with static axial slices in neutral rotation, pronation, and supination is the most useful and accurate imaging technique for the work-up of DRUJ instability. MRI is the most valuable technique in the diagnosis of TFCC lesions. The main indication for MR arthrography and CT arthrography are Palmer 1B foveal lesions of the TFCC. CLINICAL RELEVANCE STATEMENT: MRI is the method of choice for assessing TFCC lesions, with higher accuracy for central than peripheral abnormalities. The main indication for MR arthrography is the evaluation of TFCC foveal insertion lesions and peripheral non-Palmer injuries. KEY POINTS: • Conventional radiography should be the initial imaging technique in the assessment of DRUJ instability. CT with static axial slices in neutral rotation, pronation, and supination is the most accurate method for evaluating DRUJ instability. • MRI is the most useful technique in diagnosing soft-tissue injuries causing DRUJ instability, especially TFCC lesions. • The main indications for MR arthrography and CT arthrography are foveal lesions of the TFCC.

Interdisciplinary consensus statements on imaging of scapholunate joint instability.

OBJECTIVES: The purpose of this agreement was to establish evidence-based consensus statements on imaging of scapholunate joint (SLJ) instability by an expert group using the Delphi technique. METHODS: Nineteen hand surgeons developed a preliminary list of questions on SLJ instability. Radiologists created statements based on the literature and the authors' clinical experience. Questions and statements were revised during three iterative Delphi rounds. Delphi panellists consisted of twenty-seven musculoskeletal radiologists. The panellists scored their degree of agreement to each statement on an eleven-item numeric scale. Scores of '0', '5' and '10' reflected complete disagreement, indeterminate agreement and complete agreement, respectively. Group consensus was defined as a score of '8' or higher for 80% or more of the panellists. RESULTS: Ten of fifteen statements achieved group consensus in the second Delphi round. The remaining five statements achieved group consensus in the third Delphi round. It was agreed that dorsopalmar and lateral radiographs should be acquired as routine imaging work-up in patients with suspected SLJ instability. Radiographic stress views and dynamic fluoroscopy allow accurate diagnosis of dynamic SLJ instability. MR arthrography and CT arthrography are accurate for detecting scapholunate interosseous ligament tears and articular cartilage defects. Ultrasonography and MRI can delineate most extrinsic carpal ligaments, although validated scientific evidence on accurate differentiation between partially or completely torn or incompetent ligaments is not available. CONCLUSIONS: Delphi-based agreements suggest that standardized radiographs, radiographic stress views, dynamic fluoroscopy, MR arthrography and CT arthrography are the most useful and accurate imaging techniques for the work-up of SLJ instability. KEY POINTS: • Dorsopalmar and lateral wrist radiographs remain the basic imaging modality for routine imaging work-up in patients with suspected scapholunate joint instability. • Radiographic stress views and dynamic fluoroscopy of the wrist allow accurate diagnosis of dynamic scapholunate joint instability. • Wrist MR arthrography and CT arthrography are accurate for determination of scapholunate interosseous ligament tears and cartilage defects.

The prevalence of fracture extension in displaced femoral neck fractures in the elderly: A pilot study.

OBJECTIVE: Arthroplasty is the common treatment for intracapsular femoral neck fractures in the elderly. Recent studies have shown that there may be more overall complications related to uncemented hemiarthroplasty compared to cemented, including more subsidence, intraoperative fractures, and postoperative fractures. Uncemented femoral components rely on a press fit, and the risk of these complications would be expected to increase in patients with unrecognized distal extension of femoral neck fractures. The purpose of this study is to determine the frequency of fracture extension of displaced femoral neck fractures in the elderly population. METHODS: The electronic medical record database at our institution was retrospectively reviewed to search for consecutive reports from 2005 to 2015 of patients 65 years or older that sustained an intracapsular femoral neck fracture who had computed tomography (CT) examinations of the injury. Exclusion criteria were CTs that were not fine cut (<1.5 mm cuts) or occult femoral neck fractures that were seen only on magnetic resonance imaging. This resulted in 60 patients that were included in the study. Within this subset of patients, the CT scans were reassessed to look for extension of the fracture beyond the boundaries of the femoral neck. Of particular interest, were fracture lines that extended distal to the femoral neck, since these have the potential to affect the fit of an uncemented femoral stem. Data on subject age, gender, body mass index (BMI), and bone mineral density (BMD) were also collected, and it was determined if these demographics were predictive in patients having fracture extension. Treatment and follow-up data were collected for the patients as well. RESULTS: Seven of 60 patients were identified to have fracture extension of intracapsular femoral neck fractures. The frequency of fracture extension of intracapsular femoral neck fractures distal to the femoral neck was 8.3% (5/60). All cases of fracture extension were nondisplaced or minimally displaced. 60% (3/5) of the distal fracture extensions were not diagnosed preoperatively by the radiologists or the treating orthopaedic surgeons. There was not a statistically significant difference when comparing age, gender, BMI, or BMD of the population group with distal fracture extension to that of the rest of the patient cohort. CONCLUSIONS: To our knowledge, this is the first study to report the frequency of fracture extension of displaced femoral neck fractures in the elderly population. The 8.3% rate of distal fracture extension in elderly femoral neck fractures may help explain the higher rate of subsidence, postoperative fracture and intraoperative fracture when applying uncemented hemiarthroplasty compared to cemented arthroplasty. It is important to be aware of the potential for this phenomenon.

Magnetic resonance imaging of the postoperative meniscus: resection, repair, and replacement.

Meniscus surgery is common, and surgical indications and techniques continue to evolve. After highlighting relevant anatomy and emerging magnetic resonance (MR) imaging techniques, this article reviews the current indications and techniques used for meniscus surgery, evaluates the use of MR imaging protocols with and without arthrography, and focuses on MR imaging interpretation of the postoperative meniscus, with particular attention to clinical outcomes and diagnostic criteria.

Normal Anatomy of the Elbow on Conventional MR Imaging and MR Arthrography.

Conventional MR imaging allows clear depiction of the muscles, tendons, nerves, vessels, ligaments, bones, and cartilage that compose the elbow. MR arthrography can be a valuable supplementary technique for optimizing evaluation of intraarticular structures, including the undersurfaces of the collateral ligaments. Regardless of the imaging technique utilized, knowledge of normal anatomy-and normal anatomic variants-is fundamental for accurate assessment of normal and diseased states.