Suspected peroneal tendinopathy, tears, and subluxation are often confirmed preoperatively using magnetic resonance imaging (MRI) or diagnostic ultrasound (US). No study has directly compared the accuracy of these tests for the diagnosis of peroneal tendon pathology. The purpose of this study is to directly compare MRI and US to intraoperative findings in patients who underwent surgery for suspected peroneal pathology to determine the imaging diagnostic accuracy. Operative records and diagnostic images for 21 consecutive patients who had both MRI and US prior to surgery for suspected peroneal tendinopathy, tears, or subluxation were retrospectively reviewed. The results of this review are compared with the intraoperative findings to yield the sensitivity and specificity for each imaging modality. For the diagnosis of peroneal tendon tears, US was found to have a sensitivity of 88% and specificity of 100%, compared to 100% sensitivity and specificity for MRI. In the diagnosis of peroneal tendinopathy, both US and MRI had a sensitivity and specificity of 100%. In diagnosing peroneal subluxation, US was 100% sensitive compared to 66% for MRI, and both were 100% specific. In conclusion, US was found to be more effective in diagnosing peroneal subluxation and MRI was slightly more accurate in the diagnosis of peroneal tendon tears.

The knee joint relies on a combination of deep and superficial structures for stability and function. Both ultrasound and high-resolution magnetic resonance imaging are extremely useful in evaluating these struc- tures and associated pathology. This article reviews a combination of critical anatomic structures, joint abnormalities, and pathologic conditions at the knee joint, while highlighting the merits, limitations, and pitfalls of the two imaging modalities. A clear appreciation of each method paired with its relative strengths will aid in expediting diagnosis and appropriate treatment for a wide range of knee joint conditions.

An intricate and unique combination of ligamentous, fibrocartilaginous, and osseous structures stabilize the thumb metacarpophalangeal joint. Both ultrasound and high-resolution magnetic resonance imaging are extremely useful in evaluating these critical structures. This article reviews common injuries of the thumb metacarpophalangeal joint, while highlighting the merits, limitations, and pitfalls of the two imag- ing modalities. A clear appreciation of each method, paired with anatomic knowledge, will lend greater confidence and accuracy to diagnosing impactful injuries and guiding intervention.

LZTR1-associated syndromes have defined the clinical recognition of this gene, yet its population susceptibility architecture remains unclear. Here we combined population-scale variant data, systematic literature curation, standardized ACMG/AMP interpretation, and allele-frequency modeling to evaluate dominant LZTR1-associated susceptibility using a genotype-first framework. We analyzed 4,930 LZTR1 variants from gnomAD and curated 181 reported variants from 50 publications. Pathogenic and likely pathogenic variants were distributed across functional domains without strict syndrome-specific segregation and were collectively more frequent in population datasets than expected for a condition recognized mainly through rare syndrome-based ascertainment. Allele-frequency modeling predicted a population prevalence of approximately 2.5 to 2.8 per 1,000, depending on modeling assumptions, for dominant LZTR1-associated susceptibility. These results reveal a substantial gap between variant frequency and clinical recognition, support a model of dominant LZTR1-associated susceptibility as a common, variably penetrant Mendelian susceptibility state, and illustrate how genotype-first approaches can refine disease architecture beyond syndrome-based classification.