Antoine Moraux

Anatomical study of phrenic nerve using ultrasound

PurposeTo demonstrate whether ultrasonography may allow a precise assessment of the course and relations of the phrenic nerve in its cervical portion.MethodsThis study, initially undertaken in five cadavers, was followed by high-resolution ultrasonographic study in 20 volunteers (40 nerves) by two radiologists in consensus. The location, course and relations of the phrenic nerve to the adjacent anatomical structures were analysed.ResultsThe phrenic nerve could be nicely identified through the majority of its course by high-resolution ultrasonography. Useful anatomic landmarks for the detection of the nerve could be defined; these include the transverse cervical and ascending cervical arteries. Some anatomical variations were observed.ConclusionKnowledge of the nerve’s precise location, which may demonstrate individual variations, may have useful clinical applications.

Retinacular disorders of the ankle and foot.

The retinacula of the ankle are distinct structures defined as regions of localized thickening of the crural fascia covering the deep structures of the distal portion of the leg, ankle, and foot. Their role is to maintain the approximation of the tendons to the underlying bone. The retinacula of the ankle and foot contain the extensor retinaculum, the peroneal retinaculum, and the flexor retinaculum. Knowledge of the normal anatomy and imaging appearance of these structures is essential for the depiction of their injuries. Even though they may provide an explanation for chronic and unexplained residual pain after an injury, they are frequently overlooked or misdiagnosed.

Radiographic features of osteogenesis imperfecta

BackgroundOsteogenesis imperfecta (OI), commonly called “brittle bone disease”, is a genetic disorder characterised by increased bone fragility and decreased bone density due to quantitative and/or qualitative abnormalities of type I collagen. Different types of OI exist, from mild to severe; they may lead to death, multiple bone fractures, skeletal deformity and short stature.MethodsSevere cases are usually diagnosed before birth and may incite the parents to choose therapeutic abortion, whereas milder cases are much more difficult to diagnose and may be sometimes confused with non-accidental injury (NAI) (“child abuse”) in young children. Whatever the degree of severity, conventional radiography still remains the mainstay in diagnosing OI.ResultsThe prognosis of this disorder has changed in the last few years thanks to biphosphonate therapy.ConclusionThe aim of this pictorial review is to illustrate the radiographic manifestations of OI, including in children receiving biphosphonates, and to outline specific patterns that help differentiate OI from NAI when necessary.Key Points• The main radiographic features of OI are osteopenia, bone fractures and bone deformities.• Some radiographic features depend on the type of OI or may be encountered with biphosphonates.

Anatomical study of the pisotriquetral joint ligaments using ultrasonography

ObjectiveThe aim of this study was to demonstrate that ultrasonography may allow a precise assessment of the primary stabilizers of pisotriquetral joint (pisohamate, pisometacarpal, and ulnar pisotriquetral ligaments).Methods and materialsThis study was initially undertaken in eight cadavers. Metal markers were placed in the ligaments using ultrasonographic guidance, followed by the dissection of the wrists. High-resolution ultrasonography was then performed in 15 volunteers (30 wrists) for the analysis of the presence, appearance, and thickness of the ligaments.ResultsAt dissection, the metal markers were located in the ligaments or immediately adjacent to them, confirming that they were correctly depicted using ultrasonography. The three ligaments could also be identified in each volunteer. The optimal positioning of the probe and the dynamic maneuvers of the wrist allowing the strain of these ligaments could be defined. No significant changes in the appearance and thickness of the ligaments could be observed.ConclusionsThe three ligaments stabilizing the pisotriquetral joint can be identified using ultrasonography. Further studies are now required to know whether this knowledge may be useful in the assessment of pain involving the ulnar part of the wrist.

Entrapment Neuropathies of the Shoulder

Entrapment neuropathies are a rare but presumably underdiagnosed cause of shoulder pain and painful instability. Radiologists must be aware of the clinical presentations and imaging features of these neuropathies because they may be the first to suggest these diagnoses. In this article, instead of a classical nerve-by-nerve approach, entrapment neuropathies are deciphered according to the clinical situation: which anatomic structures may be involved, how to explore them, which imaging abnormalities can be expected, how to manage differential diagnoses, and which therapeutic options can be considered.

Pisotriquetral joint disorders: an under-recognized cause of ulnar side wrist pain

Pisotriquetral joint disorders are often under-recognized in routine clinical practice. They nevertheless represent a significant cause of ulnar side wrist pain. The aim of this article is to present the main disorders of this joint and discuss the different imaging modalities that can be useful for its assessment.

New MRI Sequences

Every year, manufacturers of MRI machines introduce new sequences. Most of them result in improved spatial resolution and signal contrast, occasionally with a decrease in sequence duration or MRI time (as when a single 3D sequence is substituted for three 2D sequences). Some sequences that are specifically designed to obtain structural or functional information about a specific tissue (ultrashort TE, T2 mapping, spectro-MRI) are used only for research purposes. Diffusion-weighted imaging (DWI), diffusion tensor imaging (DTI), and tractography constitute an original microarchitectural approach based on water molecule diffusion. These methods are nearly ready to be introduced into clinical practice. They are discussed in this article.

Inferiorly Displaced Flap Tear of the Medial Meniscus Sonographic Diagnosis

Meniscal tears may result from acute trauma or repetitive trauma leading to progressive degeneration. Acute tears often occur after a single traumatic event in younger, physically active patients. Chronic repetitive trauma is common in middle-aged and older patients, either athletes or nonathletes, with the patients often unaware of when the tear occurs. The medial meniscus is much more frequently involved than the lateral meniscus. 1 Magnetic resonance imaging (MRI) is considered the reference standard for noninvasive assessment of meniscal tears. Assessment of menisci with sonography has been more limited and is presumably not ideal. Nevertheless, the sonographic features of meniscal tears have to be known because these lesions may be encountered during evaluation of knee pain. The aim of this report is to describe the sonographic findings of a meniscal flap tear inferiorly displaced in the medial meniscotibial recess. To the best of our knowledge, such a description has never been reported. This sonographic feature is all the more interesting because it was not clinically suspected.

An anatomical study of the indirect tendon of the rectus femoris using ultrasonography.

AbstractᅟThe aim of this study was to demonstrate that ultrasound can allow a precise assessment of the indirect tendon of the rectus femoris using a new lateral approach.Methods and materialsFour hips were dissected for the anatomical study of the proximal rectus femoris insertions. Under ultrasonographic guidance, spinal needles piercing the direct tendon were placed in the indirect tendon, following by dissection. Then, high-resolution ultrasound was performed in 20 volunteers with assessment of the indirect tendon of the rectus femoris.ResultsAt dissection, the spinal needles were located in or immediately adjacent to the indirect tendon, thus confirming that it was correctly depicted by ultrasound. The indirect tendon could be identified in each cadaver and each volunteer with ultrasound. The optimal position of the probe to allow assessment of the indirect tendon could be defined. No significant changes in the appearance or thickness of the tendon could be observed.ConclusionThe results of our study showed that the indirect tendon of the rectus femoris muscle can be clearly depicted by sonography in healthy adult subjects. The potential applications of this new use of sonography must now be confirmed by clinical studies.Key Points• The anatomy of the proximal rectus femoris is reviewed • Until now, sonography was limited for assessing direct and conjoined tendons • The indirect tendon can be clearly depicted by sonography • A new lateral approach for studying the indirect tendon is described

Sonographic Overview of Usual and Unusual Disorders of the Rectus Femoris Tendon Origins

Rectus femoris muscle proximal injuries are not rare conditions. The proximal rectus femoris tendinous anatomy is complex and may be affected by traumatic, microtraumatic, or nontraumatic disorders. A good knowledge of the proximal rectus femoris anatomy allows a better understanding of injury and disorder patterns. A new sonographic lateral approach was recently described to assess the indirect head of the proximal rectus femoris, hence allowing for a complete sonographic assessment of the proximal rectus femoris tendons. This article will review sonographic features of direct, indirect, and conjoined rectus femoris tendon disorders.