Ultrasonography and MRI are used for imaging evaluation of patellar tendinopathy, and “thickening of the tendon” is known as one of the characteristic findings. However, there are no evidence-based quantitative criteria to help evaluate this phenomenon. The purpose of this study was to investigate an objective measure of patellar tendon thickness. Patellar tendon thickness was evaluated in 65 elite university athletes using both ultrasonography and MRI. The relationship between tendon thickness and clinical patellar tendinopathy was investigated, and the cutoff value of the tendon thickness was calculated. Of the 129 knees included in the analysis, clinical patellar tendinopathy was found in 16 knees (12.4%). The proximal patellar tendon was significantly thicker in athletes with clinical patellar tendinopathy on both ultrasonography (8.3 mm vs. 5.1 mm; p < 0.001) and MRI (9.9 mm vs. 5.5 mm; p < 0.001). Setting the cutoff value to a thickness of >7.0 mm was an accurate predictor of clinical patellar tendinopathy (ultrasonography: sensitivity 81.3%, specificity 95.6%; MRI: sensitivity 100%, specificity 89.4%). Both ultrasonography and MRI measurement of the proximal patellar tendon thickness reflected the presence of clinical patellar tendinopathy. Defining “thickening of the patellar tendon” as thicker than 7.0 mm on both ultrasonography and MRI therefore has clinical significance.

The aim of this study was to use the magnetic resonance imaging maximum-intensity projection (MRI-MIP) method for diagnostic imaging of thoracic outlet syndrome (TOS) and to investigate the stricture ratios of the subclavian artery (SCA), subclavian vein (SCV), and brachial plexus bundle (BP). A total of 113 patients with clinically suspected TOS were evaluated. MRI was performed in a position similar to the Wright test. The stricture was classified into four grades. Then, the stricture ratios of the SCA, SCV, and BP in the sagittal view were calculated by dividing the minimum diameter by the maximum diameter of each structure. Patients were divided into two groups: surgical (n = 22) and conservative (n = 91). Statistical analysis was performed using the Mann–Whitney U test. The stricture level and ratio in the SCV were significantly higher in the surgical group, while the stricture level and the ratio of SCA to BP did not show significant differences between the two groups. The MRI-MIP method may be helpful for both subsidiary and severe diagnoses of TOS.

Purpose: Acromial and scapular spine fractures after reverse shoulder arthroplasty (RSA) can impair post-operative outcomes; however, quantitative assessment of pre-fracture cortical changes remains challenging. This study evaluated longitudinal changes in inferior acromial cortical thickness after RSA using a computed tomography-based (CT-based) acromial coronal view. Methods: This multicentre retrospective cohort study included 44 patients who underwent RSA. The acromion was divided into three zones: I (lateral acromion), II (acromial base), and III (scapular spine). Inferior cortical thickness was measured at the centre of each zone. Changes were analysed from immediately post-operatively to one year and from one to two years in shoulders with corresponding CT scans. Cortical area was assessed as a secondary outcome, and the fracture cases were described separately. Results: From immediately post-operatively to one year ( n = 41), cortical thickness was unchanged in Zone I but increased in Zone II from 2.0 ± 0.5 to 2.4 ± 0.7 mm and in Zone III from 3.8 ± 1.0 to 4.6 ± 1.6 mm. From one to two years ( n = 28), Zones II and III showed further increases, whereas Zone I remained unchanged. Thickness changes correlated with cortical area changes (Spearman’s ρ = 0.55). Five shoulders (11.4%) developed fractures within two years, and delayed Zone II and III fractures showed marked preceding cortical thickening. Conclusion: Inferior acromial cortical thickening after RSA progressed selectively in Zones II and III, suggesting region-specific post-operative acromial remodelling. These findings may help clarify the differences in fracture pathomechanisms according to the location.