Long, Jeremiah R.

An understanding of regions of endemicity and the spectrum of organ system involvement can improve recognition of the imaging features of coccidioidomycosis, which can overlap with those of other diseases.

Bone scintigraphy is a valuable adjunct to cross-sectional imaging and can be used to evaluate disease extent in multifocal processes such as blastic osseous metastatic disease, provide diagnostic information to aid in problem solving in challenging cases, and serve as the primary diagnostic modality for diseases that manifest with pathognomonic scintigraphic appearances.

Objective To determine the proportion of cases of lower extremity symptoms attributable to underlying musculoskeletal ( MSK ) rather than thrombotic etiologies in emergency versus non‐emergency settings. Methods We retrospectively reviewed all lower extremity Venous Doppler ultrasounds performed on emergency department ( ED ) and non‐ ED patients over a 1‐year period at a single institution. Using radiology report data mining software, keywords including tear, tendon, hematoma, and muscle were used to identify cases of MSK pathology of the lower leg. All reports were also reviewed for findings of venous thrombosis. Statistical significance between ED and non‐ ED patients for both incidental MSK pathology and venous thrombosis was assessed using chi‐squared tests. Results A total of 5714 lower extremity Doppler ultrasounds were performed at a single institution during the 1‐year period, 1829 in the ED and 3885 in non‐ ED settings. Sixty‐nine of 1829 (3.8%) ED patients had incidental MSK pathology of the lower extremity compared to 53/3885 (1.4%) in the non‐ ED setting ( p < .001). Two hundred sixty‐seven of 1829 (14.5%) ED patients had evidence of venous thrombosis and/or chronic post‐thrombotic change. When combined with thrombotic pathology as positive cases, incidental MSK injury accounted for 69/336 (20.5%) of ED cases with positive sonographic findings. Conclusions MSK pathology of the lower leg is significantly more likely to contribute to lower extremity symptoms in the ED compared to a non‐ ED setting. Therefore, a brief sonographic evaluation of the MSK apparatus may be beneficial in a subset of ED patients, particularly those with focal pain but no identifiable thrombotic etiology.

AbstractPeripheral spondyloarthritis (pSpA) encompasses multiple entities affecting the musculoskeletal system with classic findings of synovitis, enthesitis, and tenosynovitis. It remains poorly defined when compared with the axial spondyloarthritides due to nonspecific symptoms, ill-defined imaging findings, and lack of specific testable biomarkers. Previous research has tried to distinguish between the two disease entities using clinical presentations, scoring systems, and radiographic findings; however, overlap remains. We summarize the current classification of pSpA, imaging findings, and the distinction between these entities and axial spondyloarthritis.

Case: A 25-year-old male pole vaulter presented with several months of right ankle pain. Radiographs showed an anterior tibial osteophyte with a small intra-articular body suggesting impingement. Weight-bearing computed tomography (CT) revealed an associated tibial plafond stress fracture. Subsequent arthroscopy with osteophyte resection and loose body removal significantly improved symptoms, and he gradually resumed training. Conclusion: Stress fractures should always be considered in athletes with ankle pain. A unique aspect of this case was the use of weight-bearing CT in diagnosis and surgical planning. To our knowledge, this is the first described case in which weight-bearing CT was used in this fashion.

AbstractEarly investigations into the magnetic resonance imaging (MRI) appearance of articular cartilage imaging relied on assessment of the morphology, with subsequent investigators reporting identifying increased T2 signal intensity, bright signal, in degenerated cartilage. The cartilage “black line sign” is a finding that has recently been described in the radiology literature to characterize cartilage pathology. This sign refers to a focal linear hypointense signal within articular cartilage that is oriented perpendicular to the subchondral bone on T2-weighted MRI. The diagnostic significance and clinical relevance of this sign is debated. Since its first description, several papers have further delineated the etiology, prevalence, and clinical relevance of these and other dark cartilage abnormalities. The intent of this article is to summarize these findings, with hopes of bringing to light the importance of dark cartilage lesions and their clinical implication in the world of knee surgery. We will briefly discuss the most probable etiologies of dark cartilage abnormalities and the major factors determining the unique signal intensity. The described anatomical patterns of this finding, the clinical importance, potential mimics, and current treatment recommendations will be reviewed.

AbstractWhile much detail is known about each anatomic structure of the knee and its contributory effect on biomechanics, our understanding is still evolving. In particular, the function of the meniscofemoral ligaments and their anatomical variants have yet to be fully described. In this report, a never‐before‐described anatomical meniscofemoral ligament variant intra‐substance to the PCL is presented. Arthroscopists should be aware of the novel variant as a growing number of studies have demonstrated the biomechanical importance of the meniscofemoral ligaments in protecting the lateral meniscus and supporting the function of the PCL.Level of Evidence: IV.