MR Imaging Findings Of Lesions Research Articles

Mr imaging findings of lesions involving cartilage and bone in the paediatric knee: a pictorial review

The knee is the joint which is most commonly imaged by MRI in children and adolescents. With increasing participation in competitive sports, traumatic knee injuries with osteochondral lesions are increasingly common in children. However, it is also important to exclude non traumatic conditions that result in defects of the articular cartilage and/or subchondral bone plate or growth plate of the knee, since timely diagnosis and therapy may help prevent lifelong disability in these patients. Moreover, there are normal variants that occur in the ossifying knee that should not be mistaken for lesions. The aim of this essay is to review the wide range of conditions that may result in MRI signal changes of the ossifying knee in children.

MR imaging findings of anterior interosseous nerve lesions

To study and characterise the MR imaging findings of lesions of the anterior interosseous nerve (AIN). Magnetic resonance imaging (MRI) findings of the forearm of ten patients referred to our institution with suspected AIN lesions were retrospectively studied. Five healthy volunteers with normal forearm MRI findings formed a control group. Two musculoskeletal radiologists assessed the forearm musculature for oedema in the distribution of the AIN, median, posterior interosseous and radial nerves on T2-weighted (T2W) fat-saturated sequences. T1-weighted (T1W) images were assessed and graded for the presence of muscle atrophy and fatty involution. Six patients had undergone surgical exploration; five of these had surgically confirmed AIN compression. Four patients had diagnoses other than AIN compression made on imaging features. Of the cases of proven AIN compression, oedema within the pronator quadratus (PQ) muscle was identified in all cases. PQ atrophy and fatty involution were seen in three (43%) surgically confirmed cases. Cases 2 and 3 also demonstrated oedema in the flexor digitorum profundus (FDP)1 and FDP2 muscles. These cases also showed oedema in the flexor-carpi radialis (FCR) and FDP3/FDP4 muscles, respectively. The four cases of non-AIN compression demonstrated muscle oedema patterns that were atypical for the AIN distribution. They included a rupture of the flexor pollicis longus (FPL) tendon, brachial neuritis, amyotrophic lateral sclerosis and compression of the proximal median nerve. MRI is a useful investigation in the diagnostic workup of AIN syndrome. AIN syndrome is likely when there is diffuse oedema of AIN innervated muscles on T2W fat-saturated images. The most reliable sign of an AIN lesion is oedema within the PQ. Oedema in the flexor carpi radialis, FDP3 and FDP4, although not in the classical distribution of the AIN, does not preclude the diagnosis of AIN syndrome.