Objective: To evaluate whether measurement of protruding anterior meniscus in the medial compartment (PAMM) and posterior tibial translation (PTT) can be used as a secondary sign of posterior cruciate ligament (PCL) tear for differential diagnosis of partial or complete tear. Methods: 21 cases with complete PCL tear, 35 cases with partial PCL tear, and 55 normal cases were reviewed in this retrospective study. PTT and PAMM were measured from the MR images associated with each case. Non-parametric data were evaluated using the Kruskal–Wallis test and the Mann–Whitney U-test with Bonferroni correction to compare differences among the three groups: complete tear, partial tear, and controls Results: There were significant differences in the median values of PAMM among the three groups, and with PAMM increasing as the grade of PCL injury increased. However, there were no significant differences in median PTT among the three groups. Median PAMM in the partial and complete tear groups was significantly higher than in subjects without PCL rupture (adjusted p-value <0.05). Although median PAMM in subjects in the complete tear group tended to be higher than in those with a partial tear, this difference was not statistically significant (adjusted p-values ≥0.418). Conclusion: PAMM is more useful finding than PTT and can predict PCL tear with or without posterior instability. However, PAMM cannot differentiate partial tear and complete tear of the PCL. Advances in knowledge PAMM is more useful finding than PTT and can predict PCL tear with or without posterior instability. However, PAMM cannot differentiate partial tear and complete tear of the PCL.

Purpose To evaluate the correlation between Lee’s grades and surgical intervention for central lumbar spinal stenosis (CLSS) and to assess whether this grading system can be used as a decision-making tool for the surgical treatment of this condition. Materials and Methods This retrospective study included 290 patients (M:F = 156:134; mean age, 46 ± 16 years). Radiologists assessed the presence and grade of CLSS at the stenosis point according to Lee’s grading system, in which CLSS is classified into four grades according to the shape of the cauda equina. Correlation coefficients ( r s ) between Lee’s grades and the operation were calculated with Spearman rank correlation. Results Among the operated patients, grade 2 was the most commonly assigned grade (50%–58%), grade 3 was less common (35%), and grade 0 was the least common (2%–3%). Among the non-operated patients, grade 1 was the most common (63%–65%), grade 0 was less common (15%–16%), and grade 3 was the least common (8%). The distribution of grades differed between the operated and non-operated groups ( p < 0.001). Less than 25% of patients who underwent surgery were assigned grades 0 and 1, and more than 88% were assigned grades 2 and 3. A moderate correlation was found between the grade and surgical intervention ( r s = 0.632 and r s = 0.583). Conclusion Lee’s grade was moderately correlated with surgical intervention. Lee’s grading system can be a decision-making tool for the surgical treatment of CLSS.

Background There are not many studies on the differences of ultrasound (US) findings between epidermal cysts (ECs) located in the trunk and those in the extremities. Purpose To compare the sonographic findings of ECs according to location in the body (trunk vs. extremity) and evaluated the feasibility of strain elastography (SE). Material and Methods This is a retrospective study of 76 patients with surgically confirmed non-ruptured EC who underwent US including SE. The US analyses included size, shape, ratio of depth to length (DLR), involvement of more than half the dermis, “submarine sign,” and SE characters of each lesion. SE findings were assigned into four grades based on elasticity. Results The submarine sign was more significantly observed in ECs located in the trunk versus extremities ( P value = 0.004 and 0.035, respectively). Truncal lesions were significantly more likely to possess an ovoid shape ( P < 0.05) and exhibited higher DLR ( P < 0.05). There were more cases with low elasticity according to SE (grade 3 or 4) compared to high elasticity (grade 1 or 2). However, we did not observe significant differences between the two locations ( P > 0.05). More-than-half signs also did not exhibit a significant difference ( P > 0.05). Conclusion The submarine sign, ovoid shape, and tall lesions (higher DLR) are common in the trunk. However, the degree of elasticity and number of more-than-half signs did not differ between the two groups.